Stairs. Entry group. Materials. Doors. Locks. Design

1. TYPES OF NON-METALLIC PIPES AND THE ADVANTAGES OF THEIR APPLICATION

For laying water supply and sanitation networks, it is recommended first of all to use non-metallic pipes, given their advantages over metal ones. The main disadvantage of metal, especially steel, pipes is their fragility during operation due to their corrosion. The various measures currently used to protect pipes from corrosion only slow down this destructive process, but cannot completely stop it. The rate of destruction of the walls of steel pipes due to corrosion sometimes reaches 1 mm of wall thickness per year, and if we keep in mind that pipes with a wall thickness of about 8-10 mm are used for the construction of water supply and sanitation systems, then we can calculate a rather low service life of steel pipes, which and confirmed in practice. And this is without taking into account the impact on pipes of electrocorrosion from the impact of stray currents formed near the routes of electric transport (electrified railways, tram, trolley bus, etc.) or near power lines high voltage. These stray currents cause so-called "pitting" corrosion, as a result of which through holes are formed in the pipe, which disable water pipes in a very short time. Although there are ways to protect pipes from electrocorrosion, it is not always possible to completely prevent such destruction of steel pipes.
The second equally important disadvantage of steel pipes when used in water supply systems is that during operation over time they “overgrow” with deposits inside, the roughness of the inner walls of the pipes increases and, accordingly, increases hydraulic resistance, and as a result throughput conduits is reduced. An attempt to restore it by increasing the pressure by replacing pumps pumping station to more powerful ones, often leads to ruptures in pipeline networks and shutdown of water consumers. A lot of money, labor and material resources are spent on the elimination of accidents.
In addition, in the case of the use of steel pipes for water supply systems, and sometimes for sanitation, there is an irrational use of scarce metal, from which components and parts of various machines and mechanisms could be made, instead of being buried in the form of pipes in the ground and doomed to a relatively rapid destruction by soil and electrocorrosion.
Considering all this, Gosstroy of the Russian Federation decided on the primary use for water supply and sanitation networks various kinds Not metal pipes that do not corrode and do not overgrow inside.
Range of non-metallic pipes used in plumbing construction includes their various types, including: ceramic, asbestos-cement, concrete and reinforced concrete, polyethylene, vinyl plastic, etc. Since the assortment of non-metallic and metal pipes is given in special reference books (see the list of references), in this textbook it not given.

2. INSTALLATION OF CERAMIC PIPING

Ceramic pipelines mainly serve the purposes of drainage and are non-pressure, i.e. gravity. Therefore, when laying such pipes particular importance acquire the requirements of laying them exactly according to the design slope.
Before laying, ceramic pipes delivered for construction are subjected to acceptance and quality control. At the same time, make sure that the pipes have round shape section (ovality of the trunk and the socket of the pipe should not exceed the established limits). They must be straight along the entire length, without cracks and spalls. The end planes of the pipes must be perpendicular. Pipes with hard-to-remove defects are rejected.
Pipeline laying. Installation of ceramic pipelines is carried out both as separate pipes and as enlarged links (sections) in two, three, five pipes with overall length sections no more than 8 m. Pipelines are laid from the bottom up along the slope, starting from the manhole with sockets against the flow of the waste liquid (see Fig. 18.5).
Pipes are laid on a prepared and carefully planned base in compliance with a given slope along the running sight. The first pipe is laid on the half-shell (base) of the manhole with the socket up, i.e. "from the well." Having securely fixed the first pipe, the subsequent ones are laid, connecting them with the help of sockets. The correctness of the slopes is checked with a level, and the straightness of the axis in the horizontal plane - cord. The trays of the laid pipes must match and not form ledges. The lowered pipe is led with a smooth end into the socket of the laid pipe, leaving a gap of 5-6 mm for pipes with a diameter of up to 300 mm and 8-9 mm for pipes of a larger diameter. Butt joints of pipelines made of ceramic pipes are sealed with a hemp resin or bituminous strand, followed by a lock made of asphalt mastic, cement mortar or asbestos-cement mixture. The strand is wrapped around the pipe at least two times, and then sealed with a caulk (without hammer blows). At the same time, she must take 1/3-1/2 socket (Fig. 19.1, A), and the rest of it is filled with mastic. The mastic delivered to the place of work is heated to a temperature of 160-170°C before pouring. For the convenience of filling joints, special metal clips are attached to the pipes (Fig. 19.1, b) consisting of two hinged halves. The clip is lubricated with a thin layer of clay (so that the mastic does not stick) and is installed on the pipe close to the socket. The joint is poured without interruption through the leter on one side, so that air comes out on the other. After the mastic has cooled in the joint, the clip is removed. An example of a pipe joint with termination cement mortar shown in fig. 19.1, V.
Laying pipelines in sections. To speed up the process of laying pipes in a trench and sealing their joints, they are pre-assembled into links (sections) of two, three and five pipes. Laying links of two or three pipes with a diameter of up to 250 mm can be done manually. When laying pipe links of large diameters, jib cranes and special traverses are used, which ensure the horizontal position of the links when lowered.
To speed up work on sealing joints when assembling links on a route or laying individual pipes in a trench, sometimes conical rings of asphalt mastic are attached to ceramic pipes in advance on the inner surface of the socket and on the outer surface of the other end of the pipe (Fig. 19.1, e). Before joining such pipes, the asphalt rings in the socket and at the ends of the pipes are covered with molten hot bitumen or liberally lubricated with some kind of solvent (gasoline, benzene), which softens the surface of the mastic rings. Due to the conical shape of the cast asphalt rings and the softening of their surface, it is possible free connection pipes by the so-called cold method. After evaporation of the solvent and hardening of the softened mastic, a strong and hermetic pipe joint is obtained. The general scheme for laying a pipeline from ceramic pipes is shown in fig. 19.2.

3. INSTALLATIONASBESTOS-CEMENTPIPELINES

Acceptance and quality control of pipes. Pipes must be supplied by manufacturers as a set with couplings and rubber sealing rings. All pipes and couplings, upon receipt at the on-site warehouse, must be carefully checked and, if defects are found, rejected. Only those pipes, couplings and other connecting parts that have been inspected and accepted are delivered to the installation site.
Pipe layout along the trench before installation is carried out at a distance not closer than 1 m from its edge. Pipes with a diameter of up to 150 mm can be laid out on the route in stacks up to 1 m high, located at a distance of no more than 100 m from each other. Couplings are also laid out in stacks. Pipes of large diameters are delivered directly to the laying site and laid out on the trench berm in such a way that during pipe-laying operations there is no need for their additional movements along the trench.
Installation of pressure pipelines operating pressure up to 0.6 MPa is carried out using double-shoulder asbestos-cement couplings and sealed with rubber rings round section, and for pressure up to 0.9 MPa - using the same couplings and rubber rings or cast-iron flange couplings with rubber rings. When installing asbestos-cement pressure pipelines for pressures up to 1.2 MPa, the pipes are connected only on cast-iron flange couplings with rubber rings.
Installation of pipelines from pipes of small diameters(up to 150 mm) are mainly carried out manually with lowering them, as well as connecting parts to the bottom of the trench without any devices, if its depth does not exceed 3 m. into the pipe. Pipes with a diameter of 200-300 mm are transferred from stacks and lowered to the bottom of a shallow trench on straps, and with a trench depth of more than 3 m and fastenings, using a rope or a soft cable threaded through the pipe. Pipes with a diameter of more than 300 mm are laid as close as possible to the edge of the trench, after which they are rolled up to the edge and lowered using automobile or pneumatic wheel cranes (Fig. 19.3, A). In order to speed up the installation of pipes of small and medium diameters, before laying them, they are enlarged in sections of several pieces (up to four), and then they are lowered into the trench by a crane using special traverses (Fig. 19.3, b), excluding the possibility of leakage of coupling butt joints.
Installation of pipelines on asbestos-cement double collar couplingsmax with rubber O-rings produced in this order. First, a coupling and a rubber ring are put on the end of the previously laid pipe, and a second rubber ring is put on the end of the attached pipe to be laid. The coupling is put on so that its wider edge (with a working beveled shoulder) faces the joint. After the coupling and the rubber ring are put on, the pipe to be laid is moved close to the previously laid one (Fig. 19.3, i) and they are centered. The centered pipes are fixed with a powder of soil in the middle part, and then at the ends of the pipes, the places for installing the rings are marked with chalk before and after the installation of the joint is completed (Fig. 19.3, V). Couplings are mounted using special devices - a lever jack (see Fig. 19.3, e) or, if more force is needed, a screw jack and screw tensioner (see fig. 19.3, and). The main stages of installation of a pipe coupling are shown in fig. 19.3, in-d. The correct position of the rubber rings after mounting the coupling is checked with a template or ruler. Rings should be located behind the working shoulder.
Installation of pipelines on asbestos-cement couplings CAM with rezine self-sealing rings of figured section received in Lately wide use. Installation of pipes on CAM couplings is carried out in two ways. At the first (Fig. 19.4, a, 6) the sleeve is pushed onto the pipe to be laid up to the mark made on this pipe at a distance (L-C) / 2 from the end of the pipe, where L- coupling length, C - the size of the gap between the pipes (Fig. 19.4, A), then, using a mounting device, the pipe together with the coupling is pushed towards the laid pipeline until the end of the last laid pipe enters the coupling to a depth (L-C) / 2 (Fig. 19.4, b). In order to prevent the coupling from moving during installation, a persistent (portable) clamp is installed at its end. With the second method (Fig. 19.4, c, d) the sleeve is pushed onto the pipe being laid for its entire length (Fig. 19.4, c), and then the pipe is centered with the raceway laid and, using the mounting device, the sleeve of the pipe being laid is moved to the laid pipe to the mark (L-C) / 2 on it (Fig. 19.4, G).

A - installation of individual pipes; 6 - installation of sections of several pipes by a crane using a special traverse; V, G, d - stages of installation of a coupling joint of pipes (c - marking the joint and the initial position of the first rubber ring; G - intermediate stage of installation and initial position of the second ring; d - joint in the mounted state); e - lever tension jack; and - screw jack; 1 - pipes; 2 - double collar; 3 - sling; 4 - crane hook; 5 - tap; 6 - traverse with soft towels; 7 - the first rubber ring; 8 - second ring; 9 - places for embedding with cement mortar; 10 - bed with clamp; 17 - levers; 12 - traction; 13 - grips; 14 - spacer bar; 75 - tightening screw; 16 - lever; 17 - body; 18 - screws; 19 - plank; 20 - clamps; 21 - paws

With these two installation methods, the sleeve can be initially put on and on the laid pipe. To ensure the required clearance between the pipes to be connected, a portable rod is used (Fig. 19.4, e) removed from the pipe after the installation of the joint. For the installation of butt joints of asbestos-cement pipes, along with those shown in fig. 19.3, and a lever jack is also used with a screw jack (Fig. 19.4, e) and lever-rack fixture (Fig. 19.4, g). In order to mechanize this process, a special device is also used that captures and lowers pipes into the trench, as well as joining them using CAM couplings. The device is a replaceable attachment to a single-bucket excavator and can be used to install pipes with a diameter of 300-500 mm. It is also effective attachments to the tractor "Belarus" type " mechanical arm”, which captures the pipe with the sleeve put on, lowers it to the bottom of the trench, centers and pushes the sleeve onto the previously laid pipe.
The device for mounting coupling and socket pipelines (Fig. 19.5) is made in the form of a frame suspended from the crane boom with an end-controlled cylinder placed in its middle part, an end gripper for the pipe supply and at the ends - jaw grippers of the pipe and pipeline. Each of the grippers is a two-arm levers pivotally attached to the frame and a power cylinder acting on them.
The crank mechanisms, which receive movement from the power cylinders, are fixed on the frame.
To ensure centering, centering channels are attached to the frame longitudinally from below, interacting with the pipeline and pipe with the feathers of their shelves. For preliminary orientation of the device with a pipe relative to the pipeline, brackets mounted on the frame are used.
Installation of pipelines on cast-iron couplings with rubber rings of round and trapezoidal section produced in compliance with the rules for flange connections, i.e. by gradually tightening the nuts located at the ends of mutually perpendicular diameters so that the flanges do not skew. After marking, one flange, one rubber ring and a coupling sleeve are put on the laid asbestos-cement pipe. Before laying the next pipe, a flange and a rubber ring are also put on it, and then, after laying it on the bottom of the trench, they proceed to the assembly of the joint. The degree of rubber compaction is regulated by the tension of the bolts when tightening the nuts in the prescribed manner.

Installation of non-pressure pipelines are carried out using non-pressure asbestos-cement pipes and cylindrical couplings. At the same time, a cylindrical coupling is first put on the previously laid pipe, having previously marked its actual position after assembling the joint, at each end of the pipes to be connected. The pipe to be laid is lowered into the trench and moved to the already laid one, leaving a gap as in the case of double-shoulder couplings, after which it is centered and aligned according to the sight, cord and plumb line. Next, at the end of this pipe, a detachable wooden pattern, on which the sleeve is put on, so that its middle is at the joint, and the template enters the sleeve for half its length. A hemp resin strand is placed in the gap between the coupling and the previously laid pipe and compacted with caulking. The rest of the joint gap is sealed with asbestos-cement mortar. After sealing half of the joint, the template is removed and the second half of the joint is sealed from the side of the newly laid pipe. When laying non-pressure pipelines on cylindrical couplings, the pipes are connected to the seal with asphalt mastic or cement mortar without chasing, but to obtain a joint of increased strength, cement or asbestos-cement mortar is caulked.

4. INSTALLATION OF CONCRETE AND REINFORCED CONCRETE PIPING

Concrete and reinforced concrete pipes are laid on a natural or artificial base. The joints of pressure pipes (bell-shaped or coupling) are sealed with rubber sealing rings, and non-pressure (bell-shaped or seam) - resin or bituminous strand, asbestos-cement or cement lock, as well as asphalt mastic. Before laying pipes in a trench, they, like couplings, are subjected to an external inspection during acceptance to identify defects and check dimensions.
The article was prepared and submitted digitally by the company

Concrete and reinforced concrete pipes are laid out along the trench in various ways (perpendicular to the trench, at an angle, etc.), the choice of which depends on the type and load capacity of the erection cranes used.
Installation of pressure pipelines. Pressure pipelines are mounted from socket and smooth reinforced concrete pressure pipes on coupling joints, which diversifies the technology of their laying.
Installation of pipelines from socket pipes are carried out in the following sequence: delivery of pipes and laying them out along the trench, feeding them to the laying site, preparing the end of the pipe and installing a rubber ring on it; introducing it together with the ring into the socket of the previously laid pipe; giving the laid pipe the design position - final sealing of the joint; preliminary testing of the finished unfilled section of the pipeline (and for pipes of large diameters, only butt joints); backfilling of this area; his final test.
The installation of pipes is carried out by jib cranes, and the pipes from the berm of the trench are fed with sockets forward along the installation and always against the flow of liquid. Before laying the first pipe V at the beginning of the route, a concrete stop is installed, which ensures a stable position for the first two or three pipes when they are connected into a socket. The recommended layout of mechanisms, assembly workers and pipe layout during pipeline installation is shown in fig. 19.6, A. When laying the pipe, first, according to the template, the depth of its insertion into the socket of the laid pipe is marked on its smooth end. By installing the crane in the middle of the pipe to be laid and slinging it with a semi-automatic gripper (Figure 19.6, d, c, e) or with the help of slings, or a traverse, the pipe is fed into the trench (Fig. 19.6, d,e).

A - a general scheme for organizing work (T -1, T -2, T -3, T -4, T -5 - jobs for pipelayers); b - marking the smooth (sleeve) end of the pipe with a template; a, d - slinging the pipe and lowering it into the trench using a tong grip; d - insertion of the smooth end of the pipe into the socket; e - reconciliation of the position of the pipe in the plan according to the landmarks; g - pipe centering; h - inventory pole with a plumb line; And - stretching device; 1 - pipes; 2 - tap; 3 - trench; 4 - tick grip; 5 - laid socket pipe; 6 - stacked pipe; 7 - pits; 8 - stairs; 9 - fixed sights; 10 - portable (running) sight; 11 - inventory stakes; 12 - tension screw; 13 - beam; 14 - thrust; 15 - spacer

At a height of 0.5 m from its bottom, the lowering of the pipe is stopped and a rubber ring is put on its smooth end, after which it is led into the socket of the previously laid pipe and lowered onto the prepared base. Wherein Special attention centering of the spigot end of the introduced pipe with a rubber ring relative to the lead-in chamfer of the socket of the previously laid pipe.
To align the position of the pipe being laid, a running sight is supported on its tray and then they make sure that the top of this sight is on the common line of sight with two fixed sights on cast-offs (Fig. 19.6, e, g). After aligning the pipe vertically, the grip is removed from it, the crane is released to install the next pipe and proceed to align the position of the pipe in the plan. For this purpose, inventory poles are installed along the plumb line (Fig. 19.6, h): one of them at the end of the pipe being laid, and the other at the previously laid one. According to the fixed pole installed in the well or on the mounted section of the pipeline, they check the correct laying of the pipe in the plan (Fig. 19.6, e). If necessary, it is shifted in the right direction.
Finally, with the help of a tensioner (Fig. 19.6, i), the smooth end of the pipe is inserted into the socket of the previously laid one, while monitoring the uniformity of rolling the rubber ring into the socket slot. ; a gap must be left between them (for which marking is done), and for pipes with a diameter of up to 1000 mm - 15 mm, and for pipes of large diameters - 20 mm. Having connected the pipes, remove the tensioner and knock the pipe from the sides with soil to a height of 1/4 of its diameter with its layer-by-layer compaction with manual rammers.

When installing pipelines from socket reinforced concrete pipes the most time-consuming operation is the introduction of the sleeve end of the pipe with a rubber ring into the socket of the previously laid one. To facilitate it, various devices, devices and mechanisms are used. In particular, two-three-cable external tensioners are used (Fig. 19.7, A, b), rack and hydraulic jacks(Fig. 19.7, V), internal tensioners, lever and gear winches (Fig. 19.7, d, e) bulldozers and excavators (Fig. 19.7, e, g).
For the installation of pipes with a diameter of 500, 700, 900 mm, a universal hydraulic device is also used (Fig. 19.7, And), which is fixed on the pipe, and then lowered into the trench with it. After checking the accuracy of centering the pipe and the correct location of the rubber ring, the pipe is joined to the pipeline under the action of the stroke of the hydraulic cylinder.
When choosing a pipe installation method, take into account the presence necessary equipment and mechanisms, as well as the conditions for the construction of the pipeline. Installation of pipes using a bulldozer (Fig. 19.7, e) can be done if the bulldozer is used when planning (cleaning) the bottom of the trench, i.e. when these two operations are combined. Installation of pipes with a diameter of 1000-1200 mm in trenches with a bottom width of 2.2 m is carried out using a D-159B bulldozer (Fig. 19.8). For the installation of pipes of small diameters (up to 500 mm), the Tsentrospetsstroy trust manufactured a small-sized bulldozer based on the T-548 tractor with a blade width of 1.25 m.

Installation of the pipeline using an excavator bucket (see Fig. 19.7, and) lead when laying pipes in water-saturated soils or in cramped urban construction conditions, when the trench is torn off as pipes are laid, and an excavator located nearby is used to install them by turning the bucket.
The means used for mechanization of the installation of reinforced concrete and concrete pipelines depend mainly on the type of butt joint and the diameter of the pipes. The type of butt joint determines the technical requirements for the installation equipment, and the diameter of the pipes and the dimensions of the trench determine the possible layouts for the placement of the installation equipment and the flow diagrams of the installation work resulting from this.
Main technical requirements to the equipment for mounting pipes on rubber sealing rings are: ensuring the alignment of the pipes and creating the necessary axial force for their joining. When installing pipes with a socket-screw connection, it is additionally necessary to ensure that the pipe being laid is screwed into the previously laid one. For the installation of pipes with caulking of butt joints, mechanized compaction of fibrous materials in the socket gap should be provided.
The installation of concrete and reinforced concrete pipes is currently carried out mainly according to two technological schemes. In the first case, attachments are used to the pipe-laying crane to perform all operations: capturing the pipe on the berm and lowering it to the bottom of the trench, centering the pipe being laid to the laid section of the pipeline and joining the pipes. The second scheme provides for the performance of centering and docking operations by a base machine moving along the bottom of the trench with the appropriate equipment. Each of these schemes has its own areas of application, due to the length and diameter of the pipes and the width of the trench.
Existing methods of installation of reinforced concrete pipes (especially large diameters of 1000, 1200 mm) do not provide accurate alignment during installation of the laid and previously laid pipes. Usually, the laid pipe is supported on weight by a lifting mechanism, and a longitudinal force is created by another mechanism (tractor, excavator), which ensures that the smooth end is inserted into the socket of the laid pipe. At the same time, as experience shows, it is very difficult to provide the same annular gap between the surface of the smooth end of the pipe and the inner surface of the socket in the joint, due to which the rubber ring located in this gap is not equally pinched along the perimeter of the pipes. Therefore, the rubber ring does not roll evenly as it enters the socket, and sometimes twists, which is unacceptable. It is also difficult to provide the necessary clearance at the joint between the pipes, since the pipes are pushed in until they touch in the socket, often without any control.

Rice. 19.9. Scheme hinged device for mounting reinforced concrete pipes on rubber sealing rings (A), attachments for the installation of pipes with a socket-screw connection (b) and a trench machine for the installation of socket pipes (c): 1 - emphasis - retainer; 2 - pipe clamps; 3, 9 - hydraulic cylinders; 4 - traverse; 5 - bracket; 6 - guide sleeve; 7 - stock; 8 - pipe previously laid; 10 - grips; 11 - pipe laid; 12 - wedge retainer; 13 - frame; 14 - drive of rotation and axial feed of the pipe; 15 - roller grips; 16 - capture of a previously laid pipe; 17 - pipe pusher cross beam on a horizontal frame; 18 - clamshell bucket of a pit digger; 19 - inclined boom of the pit digger; 20 - plow spoon digger; 21 - road seals; 22 - bed; 23 - pit; 24 - window for passing the bucket into the face; 25 - passive side diffuser; 26 - dump

Attached equipment for mechanized installation of reinforced concrete pipes, eliminating these shortcomings, was developed by the Tula Polytechnic Institute together with the Tula-Spetsstroy trust and other organizations. Such attachments (Figure 19.9, A) For installation of reinforced concrete pressure pipes on rubberO-rings structurally made in the form of cargo carrier beam with suspension to the hook of the pipe-laying crane. On the beam there are two grippers of the stacked pipe, a gripper of the previously laid pipe and a horizontal feed drive of the stacked pipe. The device has simple design and reliable in operation.
The hydraulic drive is carried out from the hydraulic system of the pipe-laying crane and is designed for pressure up to 10 MPa. At the same time, the force in the docking hydraulic cylinder reaches 95,000 N. Due to the large difference in the mass of pipes of different diameters, four options for such attachments have been developed: for pipes with a diameter of 500; 600 and 700; 800 and 1000; 1200-1400 mm, and changeover from one diameter to another in each variant is carried out using replaceable parts. The mass of attachments for pipes with a diameter of 1200 mm, shown in fig. 19.9, A, is 900 kg.
For the installation of pipes with a diameter of 900 mm, the Yaroslavl Institute of PTIOMES developed attachments for the pipe-laying crane TG-124. Its length is 5600, width and height are 1640 mm. weight 940 kg.
For mechanization installation of reinforced concrete pressure pipes with steelcore type RTNS attachments have been developed, including fixed and movable frames. A hydraulic cylinder is installed in the fixed frame, the rod of which is connected to a cam rod, which acts on all mechanisms of the equipment when the rod moves. An emphasis-grab is rigidly fixed on the movable frame, behind which there is a mechanism with a tong grip.
For installation of reinforced concrete non-pressure pipes with socket-winningcomm connection special attachments have been developed (Fig. 19.9, b) which consists of a frame, roller grips of the laid pipe, grip of the previously laid pipe. Stops are rigidly attached to the frame, mating with the socket and the sleeve part of the laid pipe.
With a pipe-laying crane, the attachments are brought to the pipe to be laid and fixed in roller grips. Then the attachment with the pipe is moved and lowered into the trench, brought to the previously laid pipe, which is fixed with a grip. With the help of a rotation drive and axial feed, the pipe to be laid is screwed into the socket of the previously laid pipe.
For mechanized caulking of socket pipes with fibrousmaterials a special device is used, which contains a removable caulking unit, consisting of chasings in the form of petals, attached to a three-section roller wheel, rigidly fixed on a three-section body. The case rotates on rollers of three-section capture. To carry out caulking, a removable assembly is installed on attachments. Before mounting on the pipe, a strand of hemp or other fibrous material is laid in front of the petals. After lowering into the trench with the help of hydraulic cylinders, the end of the pipe is inserted to the required distance into the socket of the previously laid one. The hydraulic motor is turned on, the petals begin to rotate, at the same time they are progressively introduced into the socket gap and produce rotational movement caulking of fibrous material.
Trust Spetstyazhtransstroy has developed a device for mechanicszirovanny seal of joints of bell-shaped pipes of big diameter. In this device, the embossing sleeve is equipped with vibration exciters, which ensures an improved quality of pressing the fibrous material into the socket slot of the pipes to be connected.
The structural diagram of a special trench machine for the installation of socket pipes is shown in fig. 19.9, V. The machine includes a basic tractor with a pipe pushing transverse beam suspended in front of it and a plow spoon digger and a pit digger placed on opposite end sides, made in the form of a longitudinally inclined boom and a clamshell bucket freely suspended from its head.
The main requirements for the quality of the installation of reinforced concrete pipelines: during the docking process, it is necessary to check the uniformity of the placement of the rubber ring and its rolling. If a backlog is observed in some part of the circumference, it is necessary to “powder” the ring with cement in this place, to exclude further uneven rolling of the ring.
Rings in the gap of socket and socket joints must be compressed by 40-50% of the thickness of their sections. They must not be twisted. In case of violation of the tightness (water tightness) of the joints, they are repaired, for which additional rubber rings or their segments are installed on the defective place using a special removable clamp (see Fig. 19.7, h).
Installation of pipelines with coupling butt joints. After centering and checking the correct laying of pipes along the cord, plumb line and sight at the ends of the pipes to be connected, markings are made with risks that determine the initial position of the rubber rings, distances a and b. When installing pipes, the coupling is set to its original position so that its end face on the working side coincides with the on the pipe at risk. The rubber ring is placed near the working ring of the coupling, which is then inserted into the conical slot of the coupling flush with its end using a caulk. At the same time, another rubber ring is put on the second pipe, placing it at a distance b from its end.
Further, with the help of mounting devices, the coupling is advanced towards the pipe to be joined with simultaneous rolling of the first rubber ring. Upon reaching the coupling on the second pipe, risks b from its end, a second rubber ring is introduced into the coupling slot, which ensures the necessary final position of the rubber rings in the joint and its water tightness. The sequence of installation of pipe joints using collarless and single collar couplings is shown in fig. 19.10.
The distance a, b and their fixing the final position of the coupling and rubber rings of the distance c, d, e are given in Table. 19.1.
Non-pressure socket and socket pipes are connected with a gap between the smooth end of the pipe and the socket surface equal to 10 and 15 mm for pipes with a diameter of 700 and more than 700 mm, respectively. The installation of non-pressure pipelines from socket and socket pipes with sealing with rubber rings is carried out by the same methods as pressure ones. Sealing joints with a hemp strand is carried out by caulking the socket to half its depth with two or three turns of tarred or bituminized hemp strand with an asbestos-cement mixture (30% asbestos, 70% cement).
Installation of a pipeline from seam free-flow pipes is associated with the need to seal seam joints. Joints of pipes with a diameter of more than 1000 mm are sealed around the entire perimeter with a hemp strand and rubbed with a 1: 1 cement mortar with a device outside the belt from this solution.
Installation of pipes with a crane using mounting bracket lead in the following sequence: mark the position of the pipe on the base; sling the pipe and lower it into the trench; lay the pipe on the base and verify its position; caulked with a resin strand and sealed with cement mortar; wrap the joint with a reinforcing mesh and monolithic it. The joints of pipes with a diameter of 2000-4000 mm, laid on a concrete and reinforced concrete base, are sealed with shotcrete along the reinforcing mesh.

Table 19.1 Distances when marking the position of the coupling and rubber rings before installation (a, b) and from the ends of the coupling to the rubber rings in the mounted joint (c, d, e) - see fig. 19.10

Coupling	Distances, mm, from the end to the mark at the end of the pipe		Distance from rubber ring
	without a collar, but	with collar, b	from the end of the coupling from the side		to its initial position, d
			Types of connections of plastic pipes and methods for their construction. When laying external water pipes from HDPE and LDPE, the main way to connect pipes is to butt-weld them with a heating tool. When installing gravity sewer pipelines, HDPE pipes are connected in the same way. PVC pipes are connected mainly with glue (GIPC-127 brand) in the socket. However, taking into account that thorough cleaning of the surfaces to be glued and careful application of glue are required, deformation of the joints is not allowed, the effect of glue on the long-term strength of PVC is observed, and harmful substances are released during work, recently socket joints sealed with rubber are widely used to connect PVC pipes. cuffs of various profiles, as well as O-rings. In this case, pipes are produced with sockets having annular grooves inside. Flanged connections are mainly used to connect plastic pipes to metal pipes. In places of passage sewer pipes from PVC through the walls of wells, couplings with one rubber ring are used as sleeves. Welding polyethylene pipes, most often contact, is carried out end-to-end (butt), into a socket with cast fittings and into a molding socket (socket welding). When welding pipes, special attention should be paid to outside diameter pipes and their ellipse (ovality). In butt welding, the maximum mismatch of the edges should not exceed 10% of the wall thickness, and the outer 900 mm and 1.5 mm - with a diameter of up to 1200 mm. The ends of the pipes for socket welding must have an external chamfer at an angle of 45 °. Resistance welding of pipes is carried out in the following sequence: installation and centering of pipes in a clamping centering fixture; pipe trimming and end degreasing; heating and melting of welded surfaces; removal of the welding heater; connection of heated weldable ends of pipes under pressure (draft); cooling of the weld under axial load. To obtain strong and high-quality pipe joints, it is necessary to strictly observe the basic welding parameters - temperature and duration of heating, depth of fusion, contact pressure during fusion and upsetting. The main requirements that must be observed when welding pipes are given in Table. 19.2. Bonding PVC (vinyl plastic) pipes carried out mainly in the socket. The process of gluing PVC pipes and fittings consists of following operations: preparation of pipe ends and sockets for gluing, gluing and curing joints. The surfaces of pipes and sockets to be glued are degreased with methylene chloride. After that, the glue is applied in a thin layer on the socket and thick on the end of the pipe. Pipes and fittings can be glued at an outside temperature of at least 5°C. Glued joints should not be subjected to any mechanical stress for 5 minutes. Glued lashes and knots before installation must be kept for at least 24 hours after gluing. Connection of PVC pipes on sockets with rubber rings. Pressure socket pipes in the trench are connected in the following order. First, the smooth end and the socket of the pipes to be connected are cleaned of dirt and oils, after which the depth of insertion into the socket is marked on the smooth end with a pencil or chalk. Then a rubber ring is inserted into the groove of the bell, lubricate it and the smooth end liquid soap, after which it is pushed into the socket to the mark. When connecting non-pressure PVC sewer pipes, couplings are used along with a socket. The technology of their connection using rubber rings is similar to that described above. To assemble socket connections of pressure and sewer pipes, tensioners are used. Table 19.2 Technological mode of flash butt welding of plastic pipes Indicators Equipment for welding and installation plastic pipelines. For welding pipes made of polyethylene, mobile units and mounting devices have been developed and are being produced. Now three types of installations are used for welding pipes with a diameter of 160 - 315, 355 - 630 and 710 - 1200 mm. Mobile installation of the Research Institute of Mosstroy for welding pipes with a diameter of 160 - 315 mm (Fig. 19.11, a, b) includes movable and fixed clamps for clamping pipes, a mechanism for processing pipe ends before welding, an electric heating disk for melting pipe ends, a mechanical power system for creating pressure during the process of melting and upsetting, as well as a control panel. Installation for welding pipes with a diameter of 355 - 630 mm is shown in fig. 19.13, V. It consists of hydraulic cylinders for lifting and lowering the mechanism for processing the ends of pipes, roller bearings and a tent. Installation for welding pipes with a diameter of 710 - 1200 mm (Fig. 19.1 1, G) consists of the actual welding unit, portable rails on supports, the base lifting and power supply machine. Fig 19.11. Installations and equipment for welding plastic (polyethylene) pipes: a - installation for welding pipes with a diameter of 160-315 mm; b - detail of the welding unit; c - installation for welding pipes with a diameter of 355-630 mm; g - the same, with a diameter of 710-1200 mm; e, f, g - a set for welding pipes with a diameter of 710-800 mm (d - centralizer; e - facing device; and - electric heater with power supply); 1 - fixed clamps; 2 - electric heating disk; 3 - end mechanism; 4 - movable collars; 5 - switch; b - welded pipe; 7 - roller; 8 - manometer for effort control; 9 - switching system; 10 - clamp; 11 - end mechanism drive; 12 - cart; 13 - Remote Control; 14 - hanging station; 15 - pipelayer - bulldozer; 16 - welding installation; 17 - guide ways; 18 - hydraulic cylinders; 19 - guides Along with the indicated mobile installations for welding plastic pipes with a diameter of 110 - 800 mm, equipment kits developed by the Spetsstroymekhanizatsiya trust are also used (Fig. 19.11, e, f, g). Laying plastic pipelines in a trench is carried out according to two main schemes for organizing welding and installation work - base and track. Under the basic scheme, pipes are welded near their object warehouse with preliminary connection of pipes in sections up to 18-24 m long or more, which are delivered to the route and there they are paired into a whip or a continuous thread for laying in a trench. In the route scheme, the pipes are laid out along the trench and welded using mobile welding machines into a continuous thread by the extension method. Laying pipelines with separate pipes. Before laying the pipes are carefully inspected and rejected. The number of pipes laid out along the trench depends on the achieved shift output. Pipes on a trench berm are often welded into sections or strands, which are then lowered into the trench on soft towels. However, under industrial conditions, especially in winter period, the installation of pipelines is carried out from separate pipes and connected in a trench by gluing or "on rubber rings by the extension method. Laying in links (sections) and lashes allows you to significantly reduce the number of welded joints on the route, increase labor productivity, the pace of laying the pipeline and the quality of work. Sections are delivered to the track and laid out along the trench. The whip is lowered into the trench manually (with a small pipe diameter) or with the help of cranes. It is allowed to lay the lash in the trench no earlier than 2 hours after welding the last joint. They lower it into the trench smoothly with the help of hemp ropes, soft towels or belts located at a distance of 5-10 m from each other, avoiding sharp bends of the whip. It is not allowed to drop welded lashes to the bottom of the trench. The laying of plastic pipelines of large diameters (up to 1000 mm or more) is carried out by pulling a whip along the bottom of a trench or lowering pipes suspended from a crane. Each of these methods has its own characteristics and scope. The pulling method most often lays polyethylene pipelines in dry soil conditions. In this case, a stationary type welding installation and guides are placed in a trench, after which the pipe is connected in series into a continuous thread. The trimmed pipes are lowered into the trench and laid on the clamps of the welding installation, then they are welded, after which the pipeline is pulled forward by a winch or other mechanisms. The article was prepared and submitted digitally by the company

Concrete and reinforced concrete pipes are laid on a natural or artificial base. The joints of pressure pipes (bell or socket) are sealed with rubber sealing rings, and non-pressure (bell or seam) - with a resin or bituminous strand, asbestos-cement or cement lock, as well as asphalt mastic. Before laying pipes in a trench, they, like couplings, are subjected to an external inspection during acceptance to identify defects and check dimensions.

Concrete and reinforced concrete pipes are laid out along the trench in various ways (perpendicular to the trench, at an angle, etc.), the choice of which depends on the type and load capacity of the erection cranes used.

Installation of pressure pipelines. Pressure pipelines are mounted from socket and smooth reinforced concrete pressure pipes on coupling joints, which diversifies the technology of their laying. Installation of pipelines from socket pipes is carried out in such

sequences: delivery of pipes and laying them along the trench, feeding them to the laying site, preparing the end of the pipe and installing a rubber ring on it; introducing it together with the ring into the socket of the previously laid pipe; giving the laid pipe the design position; final sealing of the joint; preliminary testing of the finished unfilled section of the pipeline (and for pipes of large diameters, only butt joints); backfilling of this area; his final test. The installation of pipes is carried out by jib cranes, and the pipes from the berm of the trench are fed with sockets forward along the installation and always against the flow of liquid. Before laying the first pipe, a concrete stop is installed at the beginning of the route, which ensures a stable position for the first two or three pipes when they are connected into a socket.

The most time-consuming part of the work is the connection of the sleeve end of the pipe with the socket of the already laid one. For accuracy, it is necessary to take measurements, and to give the necessary strength, they use special devices and equipment.

The installation of concrete and reinforced concrete pipes is currently carried out mainly according to two technological schemes. In the first case, attachments are used to the pipe-laying crane to perform all operations: capturing the pipe on the berm and lowering it to the bottom of the trench, centering the pipe being laid to the laid section of the pipeline and joining the pipes. The second scheme provides for the performance of centering and docking operations by a base machine moving along the bottom of the trench with the appropriate equipment. Each of these schemes has its own areas of application, due to the length and diameter of the pipes and the width of the trench.

removable clamp (see Fig. 19.7, h).

Installation of pipelines with coupling butt joints. After centering and checking the correct laying of the pipes along the cord, plumb line and sight at the ends of the pipes to be connected, marks are made with risks that determine the initial position of the rubber rings, distances a and b.

When installing pipes, the coupling is set to its original position so that its end face on the working side coincides with the risk applied on the pipe. The rubber ring is placed near the clutch working ring, which is then inserted into the conical slot of the clutch using a caulk.

flush with its end. At the same time, another rubber ring is put on the second pipe, placing it at a distance b from its end.

Further, with the help of mounting devices, the coupling is advanced towards the pipe to be joined with simultaneous rolling of the first rubber ring. Upon reaching the coupling on the second pipe, risks b from its end, a second rubber ring is introduced into the coupling slot, which ensures the necessary final position of the rubber rings in the joint and its water tightness. The sequence of installation of pipe joints using collarless and single collar couplings is shown in fig. 19.10.

Non-pressure socket and socket pipes are connected with a gap between the smooth end of the pipe and the socket surface equal to 10 and 15 mm for pipes with a diameter of 700 and more than 700 mm, respectively. The installation of non-pressure pipelines from socket and socket pipes with sealing with rubber rings is carried out by the same methods as pressure ones. The joints are sealed with a hemp strand by caulking the socket to half its depth with two or three turns

tarred or bituminized hemp strand caulked with an asbestos-cement mixture (30% asbestos, 70% cement). Installation of a pipeline from seam free-flow pipes is associated with the need to seal seam joints. Joints of pipes with a diameter of more than 1000 mm are sealed around the entire perimeter with a hemp strand and rubbed with a 1: 1 cement mortar with a device outside the belt from this solution.

Installation of pipes by a crane using a mounting bracket is carried out in the following sequence: mark the position of the pipe on the base; sling the pipe and lower it into the trench; lay the pipe on

base and verify its position; caulked with a resin strand and sealed with cement mortar; wrap the joint with a reinforcing mesh and monolithic it. The joints of pipes with a diameter of 2000-4000 mm, laid on a concrete and reinforced concrete base, are sealed with shotcrete along a reinforcing mesh (see Fig. 24.34).

The technology of installation of external pipelines largely depends on their purpose and type of laying, pipe material, their diameter, wall thickness, pipe length, the presence of ready-made insulation on them and its type (or lack of it), as well as on the provision of construction with installation elements (pipe sections, lashes) and other conditions.

Installation of pipelines from any type of pipes (or their sections) is associated with the need to connect them into a continuous thread. Pipelines on the route are assembled (mounted) from individual elements (pipes) of relatively short length, and therefore a large number of joints have to be sealed or welded. This slows down and increases the cost of laying pipelines. Somewhat facilitates the laying of pipelines, the preliminary enlargement of pipes into links or sections of two or three and more pipes.

The laying of pipelines consists in the installation and assembly of assembly units on the route - pipes (or their sections, lashes), fittings, compensators and fittings - in the design position. However, the larger mounting assembly, the fewer field joints and the easier it is to assemble pipelines. The nodes are completed and tested, as well as covered with a layer of insulation or painted at pipe procurement bases. The industrial technology of laying pipelines provides for the centralized procurement of mounting elements and assemblies, their delivery in finished form to the route, preliminary preparation of foundations and supporting structures to laying, on-precise assembly of pipelines.

The composition and sequence of work processes when laying pipelines depend on the type of pipes used (metal and non-metallic), as well as on the conditions for their laying (in cramped urban or field conditions, on flat or rough terrain, with or without natural or artificial barriers, etc.).

Work during the laying of pipelines is usually carried out in several stages, performed sequentially: checking the quality of pipes; lowering pipes into a trench; centering and laying them in a given direction and slope, fixing pipes in place; sealing joints with checking their quality; testing and acceptance.

The quality control of pipes is usually carried out twice - at the manufacturing plant (according to the established methodology, sometimes with testing them on the bench) and directly on the route before they are laid in the trench. On the route, almost all incoming pipes are subject to inspection and verification of their quality. This is extremely necessary, because the use of at least a few or even one low-quality pipe during the installation of a pipeline, especially a pressure one, will lead to breaks and accidents at the place of their installation. It is very difficult to eliminate them, since it requires stopping the operation of the conduit and digging trenches. In case of accidents on water conduits made of bell-shaped cast-iron or reinforced concrete pipes, replacing a poor-quality pipe is very difficult. If in such cases it is impossible to correct the defects of a low-quality pipe in the trench, it is necessary to destroy it (which is also not easy) and remove it, and in its place to lay an “insert”, most often from a steel pipe, since it is almost impossible to lay the same socket pipe. If it is possible to correct the defect and put the pipeline into operation, then the “insert” will always be a weak point due to the rapid corrosion of the steel pipe.

On the route, incoming pipes are accepted according to the documents (certificates, passports) of manufacturers confirming their quality. However, defects may occur in pipes due to improper loading, transportation and unloading. Therefore, before laying in a trench, the pipes are carefully inspected, their actual quality is checked and they are rejected if serious and irreparable defects are found. It is not allowed to lay pipes with cracks, chipped edges and sockets, large deviations from the circumference, i.e. with ovality, and other serious defects. The surface of the rubber cuffs and rings used for pipe joints should be smooth, without cracks, bubbles, foreign inclusions and defects that reduce their operational properties.

Pipes are lowered into the trench with the help of cranes, as well as special lifting devices. Only light pipes (small diameters) are lowered manually, using soft ropes, panels, etc. It is strictly forbidden to dump pipes into the trench. Lowering pipes into a trench with gentle slopes without fastenings is relatively easy, the lowering efficiency depends only on right choice pipe laying schemes and type of erection crane. It is more difficult to lower the pipes into the trench in the presence of fasteners with transverse struts. At the same time, pipes are laid with sequential removal and installation of spacers. All this slows down and complicates the process of laying pipes, increases its labor intensity and lengthens the construction period. To speed up and secure this process, large-sized fasteners with vertical shields, horizontal girders and spacer frames are used, located every 3-3.5 m.

Pipe laying is carried out according to two schemes. In the first scheme, the process is performed by two threads. First, the pipe-layers, using a crane, lay the pipe on the bottom of the trench and continue to work on the final alignment and its temporary fixing, and then the installers, using a compressor and pneumatic hammers, caulk the pipe joints. In the second scheme, the process is performed in three streams using two taps. Moreover, one of them lowers the pipe and continues to work with a link of installers to align and temporarily fix the pipe, and the second duplicates all these processes for laying the next pipe (second stream); the third flow for caulking (sealing) of pipe joints is performed as in the first scheme. Light pipes are lowered into trenches with fasteners with the help of small-scale mechanization or manually. Pipes or sections should be lowered with strict observance of safety rules.

Pipe laying in a given direction and slope (figure below) between two adjacent wells is carried out mainly along portable (running) sights, beacon pins or with the help of a level. Running sights are used when cleaning the bottom of the trench to the design mark. When laying a pressure pipeline on the cleaned bottom of the trench, the top of the pipes is leveled (levelled), for which purpose sights without protrusions below, installed on the top of the pipes, are used. Therefore, the length of such a sight is reduced by the value of the outer diameter of the pipes.

Laying pipes in a given direction and slope

1 - cast-off; 2 - constant sight; 3 - running sight

For laying gravity sewer pipes along a given slope, a running sight is used, which has a ledge glued at a right angle at the bottom of the heel. When laying pipes, the protrusion sight is installed vertically on the pipe tray. The pipe is considered to be laid along a given slope to the design marks if the top of the running gear and two permanent sights are in the same plane visible to the naked eye. The straightness of pipe laying is checked by plumb lines suspended on an axial wire (mooring). After installing cast-offs and half-checks, using a level, determine the marks of the shelves at the ends of the stacked area.

The line connecting the points between the centers of the permanent sights on the cast-offs has the same slope as the slope of the pipeline. This line is called the line of sight. A template with a marked axis of the pipeline is inserted into pipes of large diameters, which facilitates their laying in a given direction. To speed up the work, inventory metal portable cast-offs are used. For more accurate observance of the design slope of the pipeline tray, a visual method of an inclined beam of a level or a laser beam (sight sight) is used. With the latter method, a laser level is used, which is installed at the beginning of the site.

Gravity-flowing pipelines along a given slope can also be laid using a level. The correctness of laying the pipeline in a given direction and slope is finally checked before filling pipes and wells by leveling the bottom of the pipe and well trays, i.e. perform executive shooting. The difference in marks between the bottom of the wells and the tray at individual points of the pipeline should not differ from the design by more than a construction tolerance. The straightness of the pipeline between the wells is checked using mirrors that reflect the beam along its axis.

Fixing the pipes in place after they are laid is done either by powdering with soil, or by using wedges (for example, when laying heavy pipes of large diameters on concrete bases).

Sealing of joints is carried out when installing pressure and non-pressure pipelines from short concrete, reinforced concrete, cast iron, asbestos-cement and ceramic pipes (socket or smooth on coupling joints). The joints of pressure pipes are usually sealed with rubber rings or cuffs, and gravity pipes - with a tarred strand, asbestos-cement mixture, etc. (picture below). The joints of steel pipes are welded, and plastic pipes are welded or glued.

The tightness and water tightness of the socket joints of cast-iron pipelines are achieved by sealing the socket gap with a hemp tarred or bituminized strand, followed by a lock made of an asbestos-cement mixture that keeps the strand from being squeezed out by hydraulic pressure. Sometimes cement mortar is used instead, and in exceptional cases, lead. Recently, mastics have been used. When sealing joints with self-sealing rubber cuffs, no locks are required.

Joints of reinforced concrete pipes

a, b - socket; in - folded; 1 - smooth end of the pipe; 2 - asbestos cement; 3 resin strand; 4 - bell; 5 - cement mortar; 6 - rubber rings; 7 - cement mortar or asphalt mastic; 8 - grouting with cement mortar

Seal of socket joints with a strand. A hemp strand is inserted into the bell slot until the bell stops at such a depth that there is room for the lock device. Since the thickness of the bundle from the strand is somewhat greater than the width of the socket gap, it is pushed into the joint with the help of a caulk, with which the bundle is inserted into the annular gap first by hand, and then with strong hammer blows (during hand chasing). During mechanical chasing, the tourniquet is compacted pneumatic tool. To create the required tightness of the joint, 2-3 bundles are usually laid in the slot, moreover, so that their overlaps do not coincide along the circumference. After sealing the joint with a strand, an asbestos-cement lock is installed, laying the asbestos-cement mixture into the gap in layers-rollers (3-4 layers each) and compacting with chasing, striking them hard with a hammer. The sealed joint is covered for 1-2 days with wet burlap, which creates favorable conditions for setting and hardening of the asbestos-cement mixture.

Sealant sealants are used to seal butt joints of cast-iron socket pipes when laying pressure sewer pipelines with a maximum working pressure of up to 0.5 MPa. Most often, polysulfide sealants are used from sealing and vulcanizing pastes, to which asbestos or rubber crumbs are sometimes added. Mastics-sealants are prepared at the place of work 30-60 minutes before their use. Joints are sealed using syringes with manual or pneumatic extrusion of mastic or pneumatic installations. The sealant is introduced into the socket gap using a nozzle, which is attached to the tip of the syringe or hose of the pneumatic installation.

Lecture 29

LECTURE PLAN

ADDITIONAL LITERATURE

1. Popov A.I., Zionsky A.L., Khripunov V.A. Production of reinforced concrete pressure vibrohydropressed pipes. - M .: Stroyizdat 1979.

2. Maps of labor processes. Installation of external water supply and sewerage networks. Sh-10-9.1 and KKT-Yu.O-Z.M., Stroyizdat, 1563, 1986.

3. VNII Vodgeo. Installation guide for reinforced concrete, cast iron,
asbestos-cement pipelines. - M.: Stroyizdat, 1979.

4. Pereshivkin AD., Alexandrov A.A., Gotovtsev V.I. Installation of pressure
pipelines with butt joints on rubber seals. - M.: Stroyizdat, 1986.

TECHNICAL MEANS

1. filmstrip "The device of external pipelines from non-metallic
   pipes".

2. Poster "Concrete and reinforced concrete pipes".

3. Poster "Methods of installation of socket reinforced concrete pipes and devices used."

4. Poster "Arrangement of pipelines from reinforced concrete pipes".

Reinforced concrete and concrete pipes, for laying pressure conduits, vibrohydraulic presses are used. and centrifuge. reinforced concrete socket pipes of 3 classes (1st for pressure 1.8 MPa, 2nd - 1.3 MPa and 3rd 0.6-0.7 MPa) 5 m long and 500,600,700,800,1000 in diameter, 1200, 1400 to 1600 mm with the mass of vibrohydropresses. pipes from 1.32 to 8.2 tons and centrifuges. from 1.43 to 9.63 tons.

For non-pressure pipelines, concrete non-pressure pipes with a diameter of 100-1000 mm l \u003d 1-2 m are used, as well as reinforced concrete non-pressure pipes with a diameter of 400,500,600,800,100C,1200,1400,1600,2000,2400 mm and seam pipes with a diameter of 400,2400,3000,3400,4000 mm . Non-pressure pipes perform two varieties - norms. strength (M), way. to a depth of 3-5 m (above the top) and reinforced (y), laid to a depth of 5-6 m.

Concrete and reinforced concrete pipes are laid on a natural and artificial base. The joints of pressure pipes are socket and socket joints with waterproof sealing with their rubber seals, and non-pressure pipes are socket and seam with sealing of their resin or bituminized strand, asbestos-cement or cement lock, as well as asphalt mastic.

Before laying pipes in a trench, they, as well as couplings, during their acceptance must be subjected to an external inspection to identify possible defects, as well as to check the dimensions of the pipes. Pipe Quality Inspection is to establish compliance with their main characteristics of GOST and specifications(THAT).

Laying pipes along the edge of the trench. Concrete and reinforced concrete bell-shaped pipes, as well as other pipes, are laid out along the pipeline route in various ways, the choice of which is determined by the type and lifting capacity of the cranes received, designed to lower the pipes into the trench.

Installation of pressure pipelines. Pressure pipelines are mounted from bell-shaped and smooth reinforced concrete pressure pipes manufactured at factories by vibrohydraulic pressing or centrifugation and corresponding in quality to the requirements (for more details, see)

Installation of pipelines from socket reinforced concrete pipes lead in the following sequence: delivery of pipes and laying them along the trench, feeding them to the place of laying; preparation of the sleeve end of the pipe and installation of a rubber sealing ring on it; insertion of the pipe to be laid with the spigot end with a rubber ring into the previously laid socket; giving the newly laid pipe the design position; final sealing of the joint; preliminary testing of the finished section of the unfilled pipeline (and for pipes of large diameters, only butt joints) for tightness; backfilling this area with tamping the earth in the sinuses; final test of the backfilled pipeline. Installation of pipes is carried out using cranes, pneumatic or crawler cranes. Pipes from the trench berm to the place of laying are served with a socket forward in the course of installation. Before laying the first pipe, a concrete stop is installed at the beginning of the route, which ensures a stable position for the first two or three pipes when they are connected.

The recommended arrangement of mechanisms, pipe-laying workers and pipe layout during pipeline installation is shown in Fig. 1, a. When laying, first, according to the template, mark on the smooth end of the pipe to be laid the depth of embedding it into the socket of the laid pipe. After installing the assembly crane in the middle of the pipe being laid, a semi-automatic tong grip is lowered onto it and it is slinged. In the absence of such a grip, the pipes are slinged using slings or a traverse with towels. Then the pipe is fed into the trench by a crane. At a height of 0.5 m from its bottom, the lowering of the pipe is suspended and a rubber ring is put on its smooth end, after which it is led into the socket of the previously laid pipe and smoothly lowered onto the prepared base. In this case, special attention is paid to centering the sleeve end of the introduced coarse with a rubber ring relative to the lead-in chamfer of the socket of the previously laid pipe.

To align the position of the pipe being laid (Fig. 1, c), a running sight is supported on its tray and then it is monitored that the top of this sight is on a common line of sight with two fixed sights of the cast-off. After the pipe is aligned vertically, the grip is removed from it, the crane is released for the installation of the next pipe, and the pipe position in the planet is started to be adjusted. For this purpose, inventory stakes are installed along a plumb line: one at the end of the pipe being laid, and the other at the previously laid pipe. According to the fixed pole installed in the well or on the mounted section of the pipeline, the correct laying of the pipe in the plan is checked. If necessary, it is mixed in the right direction. After that, using a tensioner, the smooth end of the pipe to be laid is inserted all the way into the socket of the previously laid pipe, while monitoring the uniformity of rolling the rubber ring into the socket slot. Having docked the pipes, remove the tensioner and tamp the pipe with soil to a height of 1/4 of its diameter with layer-by-layer compaction with its manual rammers.

When installing conduits from socketed reinforced concrete pipes, the most time-consuming process is the introduction of the bushing end of the rough with a rubber ring into the socket of the previously laid one. To facilitate this operation, various devices, devices and mechanisms are used that determine the appropriate methods for installing pipelines. In particular, two- and three-cable external tensioners are used (Fig. 2, a, b), rack or hydraulic jacks (Fig. 2, c), internal tension devices, lever and gear winches (Fig. 2, d, e), bulldozers and excavators (Fig. 2, f, g).

For the installation of pipes with a diameter of 500, 700, 900 mm, a universal hydraulic device of the Orgtekhvodsgroy Glavvolgovodstroy trust (Fig. 2, h) is also used, which is first fixed on the pipe, and then lowered into the trench together with the pipe. After checking the accuracy of centering the pipe and the correct location of the rubber ring, the pipe is joined to the pipeline by the action of the stroke of the hydraulic cylinder.

When choosing a method for installing reinforced concrete pipes, the availability of the necessary equipment and mechanisms, as well as local construction conditions, are taken into account. Installation of pipelines using a bulldozer (Fig. 2, e) can only be carried out if the bulldozer is also used for laying the foundation of the trench, i.e. when it is possible to combine two work operations. Trust Tsentrospetsstroy manufactured a small-sized bulldozer based on the T-54V tractor with a blade width of 1.25 m, which is used for the installation of pipelines with a diameter of 500 mm or more while simultaneously laying out the foundation of trenches. The method of pipeline installation using an internal tension device can only be recommended for pipes with a diameter of 800 mm or more. Installation of the pipeline using an excavator (Fig. 2, g) is carried out when laying pipes in water-saturated soils or in cramped construction conditions, when it is not possible to open trenches in advance, and an excavator located nearby can be used for pipe installation. When connecting pipes, it is impossible to move the smooth end into the socket completely, i.e. to the full stop, and a gap should be left between the end face of the smooth end and the stop surface of the socket for pipes with a diameter of up to 1000 mm - 15 mm, and for pipes with a diameter of more than 1000 mm - 15 mm. or poor quality of the surface of the pipes and use low-quality rubber rings. Rings in the gap of socket and socket joints must be compressed by 40-50% of the thickness of their section. In case of violation of the tightness (water tightness) of the joints, additional rubber rings or their individual segments are installed directly on the defective place using a special removable clamp (Fig. 2, i). In case of damage or significant defects in reinforced concrete pipes, they are removed and replaced with steel pipe inserts using steel transition pipes

Installation of pipelines with coupling butt joints of pipes has a number of differences. So, after centering and checking the correct laying of the rough on the cord, plumb line and sight at the ends of the connected pipes, marks are made with risks that determine the initial position of the rubber rings - distances a (360.370) and b (70.80 mm). When installing pipes, the coupling is set to its original position so that its end face on the working side coincides with the risk applied on the pipe. The rubber ring is placed near the working end of the coupling and then, using a caulk, it is inserted into the conical slot of the coupling flush with its end face. At the same time, a rubber ring is also put on the second pipe and placed at a distance b from its end. Further, with the help of mounting devices, the coupling is advanced towards the pipe to be joined and at the same time the first rubber ring is rolled up. Upon reaching the coupling on the second pipe, the risks at a distance b from its end face, a second rubber ring is inserted into the coupling slot. In the course of further advancement of the coupling, this ring is also rolled up, due to which the required final position of the rubber rings at the junction is achieved.

Installation of non-pressure pipelines. Carried out from concrete and reinforced concrete pipes on socket, socket or seam butt joints. The joints of socket pipes are sealed with a hemp strand or other sealants sealed with asbestos cement or rubber rings, and seam pipes with asphalt mastic, bitumen-rubber gaskets and other sealants sealed with cement-sand mortar. Non-pressure socket and socket pipes are connected with a gap between the smooth end of the pipe and the stop surface of the socket, equal to 10 and 15 mm for pipes with a diameter of 700 and more than 700 mm, respectively.

The installation of pipelines from socket and socket pipes with sealing with rubber rings is carried out by the same methods as for pressure conduits. Joints are sealed with a hemp strand by caulking the bell to half its depth with two or three turns of tarred or bituminized hemp strand with a caulked asbestos-cement mixture (30% asbestos, 70% cement).

Installation of pipelines from seam free-flow pipes is associated with the need to seal the seam joints. At the same time, the joints of pipes with a diameter of more than 1000 mm are sealed around the entire perimeter with a hemp strand and rubbed with a 1: 1 cement mortar with a device outside the belt from this solution. Joints of Maltz pipes with a diameter of 2000-4000 mm, laid on concrete or reinforced concrete bases, are sealed with shotcrete along the reinforcing mesh. In this case, the pipes are laid in the trench with a crane using a mounting bracket. Installation of pipes is carried out in the following sequence: mark the position of the rough on the base; sling the pipe and lower it into the trench; lay the pipe on the base and verify its position; caulk the joint with a resin strand and seal it with cement mortar; wrap the joint with reinforcing mesh and monolithic it.

fig.1

a - the general scheme of organization of work

b - pipe laying and alignment

1 - pipes

3 - trenches

4 - pits for sealing joints

5 - pincer grip

6 - running sight

7 - sewn-on sights

Concrete and reinforced concrete pipes are laid on a natural or artificial base. The joints of pressure pipes (bell or socket) are sealed with rubber sealing rings, and non-pressure (bell or seam) - with a resin or bituminous strand, asbestos-cement or cement lock, as well as asphalt mastic. Before laying pipes in a trench, they, like couplings, are subjected to an external inspection during acceptance to identify defects and check dimensions.

Installation of pressure pipelines. Pressure pipelines are mounted from socket and smooth reinforced concrete pressure pipes on coupling joints, which diversifies the technology of their laying.

Installation of pipelines from socket pipes lead in the following sequence: delivery of pipes and laying them along the trench, feeding them to the place of laying, preparing the end of the pipe and installing a rubber ring on it; introducing it together with the ring into the socket of the previously laid pipe; giving the laid pipe the design position; final sealing of the joint; preliminary testing of the finished unfilled section of the pipeline (and for pipes of large diameters, only butt joints); backfilling of this area; his final test.

The installation of pipes is carried out by jib cranes, and the pipes from the berm of the trench are fed with sockets forward along the installation and always against the flow of liquid. Before laying the first pipe, a concrete stop is installed at the beginning of the route, which ensures a stable position for the first two or three pipes when they are connected into a socket.

The recommended layout of mechanisms, assembly workers and pipe layout during pipeline installation is shown in fig. 6.11, a. When laying the pipe, first, according to the template, the depth of its insertion into the socket of the laid pipe is marked on its smooth end. Having installed the crane in the middle of the pipe being laid and slinging it with a semi-automatic grip (Fig. 6.11, c, d, e, f) or using slings or a traverse, the pipe is fed into the trench (Fig. 6.11, f). At a height of 0.5 m from its bottom, the lowering of the pipe is stopped and a rubber ring is put on its smooth end, after which it is led into the socket of the previously laid pipe and lowered onto the prepared base. In this case, special attention is paid to centering the spigot end of the introduced pipe with a rubber ring relative to the lead-in chamfer of the socket of the previously laid pipe.

To align the position of the pipe being laid, a running sight is supported on its tray and then they make sure that the top of this sight is on a common line of sight with two fixed sights on cast-offs (Fig. 6.11, e). After aligning the pipe vertically, the grip is removed from it, the crane is released to install the next pipe and proceed to align the position of the pipe in the plan. For this purpose, inventory poles are installed along the plumb line (Fig. 6.11, h): one of them is at the end of the pipe being laid, and the other is at the previously laid one. According to the fixed pole installed in the well or on the mounted section of the pipeline, the correct laying of the pipe in the plan is checked (Fig. 6.11, e). If necessary, it is shifted in the right direction.

Finally, with the help of a tensioner (Fig. 6.11, i), the smooth end of the pipe is inserted into the socket of the previously laid one, while monitoring the uniformity of rolling the rubber ring into the socket slot. In this case, it is impossible to allow the end of the sleeve end to be pushed into the socket until it stops; a gap must be left between them (for which marking is done), and for pipes with a diameter of up to 1000 mm - 15 mm, and for pipes of large diameters - 20 mm. Having connected the pipes, remove the tensioner and knock the pipe from the sides with soil to a height of 1/4 of its diameter with its layer-by-layer compaction with manual rammers.

Rice. 6.11 - Basic work steps during the installation of a pipeline from reinforced concrete socket pipes

a-general scheme organization of work (T-1, T-2, T-Z.T-4, T-5 - workplaces of pipelayers), b - marking the smooth (sleeve) end of the pipe with a template, c, d - slinging the pipe and lowering it into the trench with the help of a tong grip, d - insertion of the smooth end of the pipe into the socket, e - alignment of the position of the pipe in the plan according to the poles, g - centering the pipe, h - inventory pole with a plumb line; and - tension device, 1 - pipes, 2 - crane, 3 - trench, 4 - tongs, 5 - laid socket pipe, 6 - laid pipe, 7 - pit; 8 - ladder, 9 - fixed sights, 10 - portable (running) sight, 11 - inventory poles, 12 - tension screw, 13 - beam, 14 - thrust, 15 - spacer

When installing pipelines from socketed reinforced concrete pipes, the most time-consuming operation is the introduction of the sleeve end of the pipe with a rubber ring into the previously laid socket. To facilitate it, various devices, devices and mechanisms are used. In particular, two-three-cable external tensioners are used (Figure 6.12, a, b), rack and pinion and hydraulic jacks (Figure 6.12, c), internal tensioners, lever and gear winches (Figure 6.12, d, e), bulldozers and excavators (Fig. 6.12, f, g).

For the installation of pipes with a diameter of 500, 700, 900 mm, a universal hydraulic device is also used (Fig. 6.12, i), which is fixed on the pipe, and then lowered into the trench with it. After checking the accuracy of centering the pipe and the correct location of the rubber ring, the pipe is joined to the pipeline.

When choosing a pipe installation method, the availability of the necessary equipment and mechanisms, as well as the conditions for the construction of the pipeline, are taken into account. Installation of pipes using a bulldozer (Fig. 6.12, e; 6.13) can be carried out if the bulldozer is used when planning (cleaning) the bottom of the trench, i.e. when these two operations are combined. The method of pipeline installation using an internal tensioning device is recommended for pipes with a diameter of 800 mm or more.

Installation of the pipeline using an excavator bucket (see Fig. 6.12, g) is carried out when laying pipes in water-saturated soils or in cramped urban construction conditions, when the trench is torn off as pipes are laid, and an excavator located nearby is used to install them by turning the bucket.

The means used for mechanization of the installation of reinforced concrete and concrete pipelines depend mainly on the type of butt joint and the diameter of the pipes. The type of butt joint determines the technical requirements for the installation equipment, and the diameter of the pipes and the dimensions of the trench determine the possible layouts for the placement of the installation equipment and the flow diagrams of the installation work resulting from this.

The main technical requirements for equipment for mounting pipes on rubber sealing rings are: ensuring the alignment of the pipes and creating the necessary axial force for their joining.

When installing pipes with a socket-screw connection, it is necessary to ensure that the pipe being laid is screwed into the previously laid one. For the installation of pipes with caulking of butt joints, mechanized compaction of fibrous materials in the socket gap should be provided.

Rice. 6.12 - Methods of mounting bell-shaped pressure reinforced concrete pipes and used for this device

1 - laid and laid pipes, 2 - half-clamp, 3 - rubber ring, 4 - cable, 5.6 - thrust and working beams, 7 - tension screw, 8 - ratchet device, 9 - hinged clamp, 10 - adjusting crosses , 13 - ratchet, 14 - concrete stop, 15 - hydraulic cylinders, 18 - pipe-laying crane, 19 - bell, 20 - lever winch, 21 - blocks, 22 - cable to the winch, 23 - thrust bar, 24 - bulldozer or tractor, 25 - excavator bucket, 26 - removable and repair clamps, 27 - support clip, 28 - pusher, 30 - repair rubber ring, 31 - bolts, 32 - traverse, 33 - levers, 34 plate, 35 - clamping pads, 36 - clamp for pipes, 37 - hook

Rice. 6.13 - Installation of reinforced concrete pipes with a diameter of 1000 - 1200 mm using a bulldozer: 1.2 - laid and laid pipes, 3 - bulldozer, 4 - assembly crane, 5 - laying pipes

The installation of concrete and reinforced concrete pipes is currently carried out mainly according to two technological schemes. In the first case, attachments are used to the pipe-laying crane to perform all operations: capturing the pipe on the berm and lowering it to the bottom of the trench, centering the pipe being laid to the laid section of the pipeline and joining the pipes. The second scheme provides for the performance of centering and docking operations by the base machine with the appropriate equipment moving along the bottom of the trench. Each of these schemes has its own areas of application, due to the length and diameter of the pipes and the width of the trench. With similar parameters, the advantage of the first scheme is the combination of rigging and docking operations performed by one machine (subject to preliminary separation of the pits and a fillet device). The advantage of the second scheme is the possibility of combining equipment for extracting pits and a fillet device with equipment for joining pipes in one machine.

The disadvantage of these methods of installation of reinforced concrete pipes (especially large diameters of 1000, 1200 mm) is the difficulty in ensuring accurate alignment during installation of the laid and previously laid pipes. Usually, the laid pipe is supported on weight by a lifting mechanism, and a longitudinal force is created by another mechanism (tractor, excavator), which ensures that the smooth end is inserted into the socket of the laid pipe. At the same time, it is difficult to provide the same annular gap between the surface of the smooth end of the pipe and the inner surface of the socket at the joint, and as a result, the rubber ring may be twisted.

Attachments for mechanized installation of reinforced concrete pipes on rubber sealing rings (Fig. 6.14, a), excluding these shortcomings, are structurally made in the form of a load-bearing beam with a suspension to the hook of a pipe-laying crane. On the beam there are two grippers of the stacked pipe, a gripper of the previously laid pipe and a horizontal feed drive of the stacked pipe.

For the installation of reinforced concrete non-pressure pipes with a socket-screw connection, attachments are used (Fig. 6.14, b), which consists of a frame, roller grippers of the pipe being laid, and a gripper of the previously laid pipe. Stops are rigidly attached to the frame, mating with the socket and the sleeve part of the laid pipe.

Rice. 6.14 - Schemes of a hinged device - for mounting reinforced concrete pipes on rubber sealing rings (a), for mounting pipes with a socket-screw connection (b) and a trench machine for mounting socket pipes (c)

1 - stop-lock, 2 - pipe clamps, 3, 9 - hydraulic cylinders, 4 - traverse, 5 - bracket, 6 - guide bushing, 7 - rod, 8 - previously laid pipe, 10 - grippers, 11 - laid pipe, 12 - wedge lock, 13 - frame, 14 - drive for rotation and axial feed of the pipe, 15 - roller grippers, 16 - gripper of the previously laid pipe, 17 - pipe pusher cross beam on a horizontal frame, 18 - grab bucket of the pit digger, 19 - inclined boom of the pit digger, 20 - plow digger, 21 - road compactor, 22 - bed, 23 - pit, 24 - window for passing the bucket into the face, 25 - passive side diffuser, 26 - blade

For mechanized caulking of socket pipes with fibrous materials, a special device is used, which contains a removable caulking unit.

For mechanized sealing of joints of large-diameter socket pipes, devices are used in which the embossing sleeve is equipped with vibration exciters, which ensures an increased quality of pressing the fibrous material into the socket gap of the pipes being connected.

The design diagram of a special trench machine for the installation of socket pipes is shown in Figure 6.14, c.

To ensure the watertightness of butt joints, pipes, sockets and couplings should not be elliptical or their surface should be of poor quality, and poor-quality rings should not be used. The main requirements for the quality of the installation of reinforced concrete pipelines: during the docking process, it is necessary to check the uniformity of the placement of the rubber ring and its rolling. If there is a backlog in some part of the circumference, it is necessary to “powder” the ring with cement in this place, to exclude further uneven rolling of the ring; as pipes are laid, it is necessary to check the straightness of the pipeline; During installation, care must be taken to inner surface the pipeline was not contaminated, no foreign objects remained inside. During breaks in work, the ends of the laid pipeline should be closed with plugs.

Rings in the gap of socket and socket joints should be crimped by 40 - 50% of the thickness of their sections. They must not be twisted. In case of violation of the tightness (water tightness) of the joints, they are repaired, for which additional rubber rings or their segments are installed on the defective place using a special removable clamp (Fig. 6.12, h).

Installation of pipelines with coupling butt joints. After centering and checking the correct laying of the pipes along the cord, plumb line and sight at the ends of the pipes to be connected, marks are made with risks that determine the initial position of the rubber rings, distances a and b. When installing pipes, the coupling is set to its original position so that its end face on the working side coincides with the risk applied on the pipe. The rubber ring is placed near the working ring of the coupling, which is then inserted into the conical slot of the coupling flush with its end using a caulk. At the same time, another rubber ring is put on the second pipe, placing it at a distance b from its end.

Further, with the help of mounting devices, the coupling is advanced towards the pipe to be joined with simultaneous rolling of the first rubber ring. Upon reaching the coupling on the second pipe, risks b from its end, a second rubber ring is introduced into the coupling slot, which ensures the necessary final position of the rubber rings in the joint and its water tightness. The sequence of installation of pipe joints using collarless and single collar couplings is shown in fig. 6.15.

Distances a, b and their fixing the final position of the coupling and rubber rings distances c, d, e are given in Appendix 3.

Rice. 6.15 - Installation of pipe joints using collarless (a) and single collar (b) couplings: I - the first stage of installation and the initial position of the first rubber ring; II - the second stage and the initial position of the second rubber ring; III - final position of the coupling and rubber rings in the mounted joint

Installation of non-pressure pipelines carried out from concrete and reinforced concrete pipes on socket, socket or seam butt joints. The joints of socket pipes are sealed with a hemp strand or other sealants sealed with asbestos cement or rubber rings, and seam pipes with asphalt mastic, bitumen-rubber gaskets and other sealants sealed with cement-sand mortar.

Non-pressure socket and socket pipes are connected with a gap between the smooth end of the pipe and the surface of the socket, equal to 10 and 15 mm, for pipes with a diameter of 700 and more than 700 mm, respectively. The installation of non-pressure pipelines from socket and socket pipes with sealing with rubber rings is carried out by the same methods as pressure ones. Sealing of joints with a hemp strand is carried out by caulking the socket to half its depth with two or three turns of tarred or bituminized hemp strand with caulking with an asbestos-cement mixture.

The joints of the pipeline from folded non-pressure pipes with a diameter of more than 1000 mm are sealed around the entire perimeter with a hemp strand and rubbed with a 1: 1 cement mortar with a device outside the belt from this solution.

Installation of pipes by a crane using a mounting bracket is carried out in the following sequence: mark the position of the pipe on the base; sling the pipe and lower it into the trench; lay the pipe on the base and verify its position; caulked with a resin strand and sealed with cement mortar; wrap the joint with reinforcing mesh and monolithic it. Joints of pipes with a diameter of 2000 - 4000 mm, laid on a concrete and reinforced concrete base, are sealed with shotcrete along a reinforcing mesh.