MINISTRY OF EDUCATION AND SCIENCE OF THE RF
Federal state AUTONOMOUS educational
institution higher education
"Sevastopol State University »
Institute of Shipbuilding and Maritime Transport
D.V. Burkov, E.S. Kolesnik
Fight against ship sinking
Educational and Methodological Council of the Institute
as a teaching aid
for full-time and correspondence forms training
specialties:
05/26/06 – Operation of ship power plants and
05/26/07 – Operation of ship electrical equipment and automation equipment
full-time and part-time forms of education
Sevastopol
UDC 656.612.088
BBK 39.46
Reviewers: S.V. Taranenko, Ph.D., Associate Professor, department. SEA
A.R. Ablaev, Ph.D., Associate Professor, department. EMSS
E.S. Solodova, Ph.D., Associate Professor, Department of Russian Geology and Humanities
D.V. Burkov, E.S. Kolesnik
Fight against ship sinking: educational and methodological manual for practical training in the discipline “Life Safety”, Part 1 Life Safety (marine), Module 2. Survival in extreme conditions on the ship. – Sevastopol: Federal State Educational Institution of Higher Education “SevGU”, 2015. – 16 p.
Methods for repairing cracks and holes in a ship's hull and eliminating damage to pipelines are considered. Procedures for placing the patch and cement box are described. A methodology for drawing up an operational plan for combating water, restoring stability and straightening a damaged vessel is presented.
The manual is intended for full-time and part-time students of Sevastopol state university, Institute of Shipbuilding and Maritime Transport, specialties: 05/26/06 – Operation of ship power plants and 05/26/07 – Operation of ship electrical equipment and automation equipment.
The educational manual provides the study of the following areas of competence in accordance with the STCW Convention:
RC 30 – Development of an action plan for emergency situations and schemes to combat the survivability of the vessel, as well as actions in emergency situations:
RK 30.1 – Ship design, including means of combating survivability.
© Burkov D.V., Kolesnik E.S., 2015
© Publication of the Federal State Educational Institution of Higher Education "SevGU", 2015
| 1. Plugging small holes and cracks ……………...……. | |
| 2. Repair of damage to piping ……….………... | |
| 3. Plasters (Mats)…….…………………………... ………………………………………………………... | |
| 4. Plaster placement (Matting)…………... ……………………………………………. | |
| 5. Cement box fixing…………………………………….. | |
| 6. Methodology for drawing up an operational plan to combat water, restore stability and righting of a disabled vessel (Operational plan technique to combat water, restore stability and righting of a disabled vessel)…………………………………………… ……. | |
| 7. Report content of the work implementation | |
| 8. Control questions………………………………………………………….. | |
| Reference list……………………………………………………………… |
Goal of the work: 1. Study of methods for sealing small holes and cracks.
2. Familiarization with the technique of applying the patch.
Repairing small holes and cracks
Sealing with emergency wedges and plugs(Fig. 1, a): wedge 7 (or conical plug 2), wrapped in tow (tow), oiled or soaked in red lead, is hammered into the crack (or hole from a fallen rivet) with a sledgehammer. Sealing should begin from the widest part of the crack; as it narrows, the thickness of the wedges decreases. The gaps between the wedges and very narrow areas of the crack are caulked with strands of oiled or red lead-impregnated tow. With low water pressure, the work can be done by one person, and with high pressure - at least two people.
Narrow, tearing cracks can be repaired mastic, heated to a dough-like state and composed of seven parts coal tar and one part sulfur with the addition of slaked lime.
The hole from the fallen rivet is sealed cork(described above) or swivel head bolt(Fig. 1, b): bolt 3 is inserted into the hole in the casing 7, while head 6 rotates spontaneously, with inside put wooden spacer 5 and washer 4.
The objective of the work: 1. Study the ways of plugging small holes and cracks.
B.2.2.1: Water flow into the compartment. Actions to take when water ingress is detected.Q.2.2.2: What means are used to seal the hole?
A: Depending on the size of the hole, the following are used: wooden wedges, driven manually from the inside of the body; shuminator plugs, thrust emergency bars available in emergency supplies, sliding mechanical stops; placing a patch on the hole and pumping water out of the compartment, placing a cement box (installation, wedging the formwork, pouring cement mortar using liquid glass). If there are holes larger than the size of the patch, they are sealed by special emergency rescue services (ASTR) using caissons.
B.2.2.3: Types of patches used to seal a small hole. Equipment of the patch.
A: Plasters are divided into chain mail, stuffed and lightweight types. For crew training, a training patch is provided. The patches are made in the form of a square from several layers of tarpaulin coated with lyctros. At the corners of the square and in the middle of each side, metal thimbles are inserted into the lyktros, to which the appropriate gear is attached for applying the plaster to the hole site.
B.2.2.4: The procedure for applying a patch to a hole. A: The patch is brought to the hole on the deck and unrolled. The keel ends are inserted under the hull of the vessel; steel sheets and guy ropes are spread across the deck. The under-keel ends on the side of the hole are fastened with staples to the thimbles of the lower luff of the plaster, and the ends of the opposite side are driven through rosin blocks onto winches or onto grab hoists spaced along the deck. Steel sheets are attached to the luff thimbles of the patch and laid on bollards, cleats, dowels, and other parts of the hull on the deck for etching them, using rosin blocks if necessary. Guys are attached to the side luffs of the patch by thimbles and carried to the bow and stern to move the patch along the side. A control line with markings is attached to the middle of the luff to determine the immersion of the patch from the main deck. The patch is dumped overboard, and the slack in the keel ends is removed manually by pulling the sheets. Having selected the slack of the under-keel ends, they are placed on the winch drums (or grab hooks), and the patch is applied to the hole using guy ropes. The correct installation of the patch is controlled from inside the ship's hull, the sheets, jack ends, guys are tightened and everything is secured. The patch is wound up.
B.2.2.5: Setting up the cement box. Preparation of the solution
A: The most common way to seal a hole is to place a cement box on the damaged area, which allows you to seal the hole and partially restore the damaged strength of the hull in the area of damage. The solution for filling a cement box consists of cement and aggregate - sand, taken in a one to one proportion. To prepare concrete, gravel, crushed stone, and broken crushed brick can be used as aggregates. The composition is made in the following proportion: cement - 1 part; gravel, crushed stone - 1 part (by volume); sand - 1 part. All aggregates, such as sand, gravel, must be washed in clean water and not have fatty impurities, since the presence of the latter impairs the strength of concrete. It is best to choose a place for preparation, as close as possible to the area of the hole. The solution is prepared on a clean deck or in special box- created. To do this, filler is poured into the gvoril over the entire area in an even layer, on top of which a layer of cement is poured, and then filler again. All three layers are thoroughly mixed and raked along the edges of the mortar, forming a funnel in the center for water (fresh or sea) in an amount equal to approximately half the weight of the cement. The resulting solution is mixed with shovels until a homogeneous mixture is obtained. Then a cement box, prepared in advance and placed on the damaged area, is filled with this mixture. The design of the cement box is such that it has neither a bottom nor a lid. One open side fits tightly to the site of damage, and through the second open side it is filled with concrete. To ensure that the box fits tightly to the damaged area, pads made of felt or resin tow can be used. If not large sizes damage (cracks, etc.) the box can be immediately filled with concrete. If there is a hole of significant size, it must first be covered with reinforcement made of steel tubes and rods arranged in the form of a grid with cells (from 0 to 25 cm) tied at intersections with wire. To avoid When the concrete is washed away by water seeping through the hole, before it finally hardens, special drainage tubes are installed in the cement box to drain the water. After the concrete has hardened, they are closed with plugs.
B.2.2.6: Reinforcement of watertight bulkheads of compartments adjacent to the flooded one.
A: A column of water in a flooded compartment creates pressure on the bulkheads of adjacent empty compartments, which become deflected: steel sheets may rupture along the weld joints and flooding of the adjacent compartment and, as a result, deteriorate the stability of the vessel, and possibly loss of buoyancy. To reinforce the bulkheads, timber from emergency supplies is used: boards, beams, wedges. Approximately 1/3 of the water column in the flooded compartment on the adjacent bulkhead, boards are installed across the vessel and propped up with beams at an angle to the deck, which are attached to it and the boards. The support is ready.
Plasters used as emergency equipment are soft, wooden, metal and pneumatic.
Soft patches are applied to temporarily seal the hole in order to drain the flooded compartment and then reliably restore the waterproofness of the hull. The most durable soft plaster is the chainmail plaster. It is elastic, fits well to the figured surface of the ship's hull and at the same time has a certain rigidity, which is created by chain mail in the form of intertwined rings made of flexible galvanized steel cable with a diameter of 9 mm.
The lightweight plaster, measuring 3x3 m, consists of two layers of canvas with a felt pad between them. To give rigidity to the plaster, 25 mm steel pipes or a steel cable with a diameter of 20 mm are attached on its outer side parallel to the upper edge at half-meter intervals.
The stuffed plaster (2x2 m) is made of two-layer canvas and a stuffed mat stitched on the inside with a dense, thick pile on the outside.
The mattress patch can be made by the crew on board. For this purpose a canvas bag required sizes stuffed with resinous tow to a thickness of about 200 mm. From the outside, narrow boards 50–75 mm thick (with gaps between them) are attached to the mattress thus obtained, and a steel cable is nailed to them with construction staples for winding.
A wooden rigid plaster is usually made on site on the ship after a hole has been received in the hull. It is most appropriate to use it to close holes located near or above the waterline, as well as in cases where the hole can be exposed by heeling or trimming the vessel.
Metal patches used to seal small holes are shown in Fig. 6
Pneumatic plasters (tubular, spherical, soft box-shaped, semi-rigid and rigid) are designed for sealing small holes from the outside at a depth of up to 10 m.
Holes with a diameter of 35 – 100 mm with a height of torn edges up to 15 mm can be repaired metal patch with a clamping bolt PB-1. The patch can be installed by one person and does not require additional fastening after installation. On the ship, the PB-1 patch (Fig. 5) is stored in constant readiness for use, assembled, the nut with handles should be in the upper threaded part of the clamping bolt.
To install a patch on a hole you need:
install the rotary bracket, overcoming the force of the spiral spring, parallel to the axis of the clamping bolt;
Insert a clamping bolt with a rotating bracket into the hole so that, when it goes beyond the casing, it rotates under the action of a spring perpendicular to the axis of the clamping bolt;
holding the patch by the bolt, rotate the nut using the handles and press the rubber seal with the pressure disk against the casing until water leaks from the hole are eliminated.
The non-working surfaces of the patch are painted with red lead, the working surfaces (pressure bolt, spring, nut thread) are lubricated with grease, the rubber seal is covered with chalk.
During operation, ships may suffer damage to their underwater hulls for a number of reasons. Most often this occurs due to ship impacts on the ground, port facilities and various underwater objects, as well as ship collisions. Damage to the underwater parts of ships and watercraft is also possible as a result of overstressing of the hull during strong pitching or when sailing in ice. 116
Damage to the body can be of three types: holes, cracks and loose seams; Damage to the hull also includes the loss of rivets (on old riveted ships).
Holes in the body can have a wide variety of configurations and areas from several square centimeters to tens of square meters. Holes are characterized by torn and bent edges, as well as dents around them, which makes them difficult to seal and requires the use of various plasters.
Cracks and split seams can also vary in size various sizes, but in most cases they are small in width, which makes them easier to embed.
Inspection of hull damage. If the location of the damage is unknown, divers examine the hull from the keel end or keel ladder. A detailed examination of the damage site and taking measurements, as well as its repair, should be carried out from a working gazebo. During the inspection, it should be borne in mind that when water enters the hole, there is a danger of the diver being pulled or sucked into the hole. Therefore, the diver must inspect and examine the hole from the side, taking a position that prevents him from being pulled in or drawn to the hole.
When examining cracks and split seams, the diver determines their length and direction, as well as their width, so that he can then choose the right wedges to seal them. Inspection of holes in flat areas of the body consists of taking their dimensions and inspecting the edges in order to determine the possibility of installing a patch and the need to cut torn and bent parts; The dimensions of the holes are taken using a diving ruler or some kind of block on which the diver makes notches.
If the hole is located on the ship's bilge in the area of the stem or sternpost and to seal it it is necessary to install a figured patch, the diver, using templates, removes the hull contours around the hole. Templates are also removed to apply plasters to holes surrounded by dents. The most convenient templates are made of wood in the form of boxes or squares (Fig. 75); The box template is a quadrangular frame made according to the measured dimensions of the hole with the calculation of its overlap on all sides by 10-15 cm. On both sides of the frame, and if necessary according to the shape of the area where the hole is placed on its four sides, movable ones are attached to one nail slats. The template made at the under-keel ends is brought to the hole, and the diver installs it in the same way as a plaster would be installed. After installing the template, the diver brings the slats one by one close to the ship’s hull and secures them with nails. - The finished template is taken away from the side at the keel ends and lifted upward.
To remove the shape of the patches in the stern and stem areas, angle templates are used, which are made from two boards or bars with slats stuffed on them. Adjusting the slats according to
The installation of the square template at the heel ends is carried out in the same way as for a box template. If there is a significant change in the curvature of the body, two square templates are fastened at a distance equal to the width of the future patch.
Seal cracks, loose seams and small holes. To repair minor damage to the ship's hull, wooden blunt and pointed plugs and wedges are used; their dimensions are determined based on the results of the inspection so that when driven in, they fit at least 2/3 of the length into the damage being repaired.
Rice. 75. Templates for removing body contours:
a - box template; b - template-ugolnnk
Small plugs and wedges are supplied to the diver at the hemp end with ballast into which they are stuck between the strands; large ones are pre-ballasted. The diver inserts a plug into the hole and hammers it in with a sledgehammer. If the plug does not hold tightly enough or has entered the hole less than 2/3 of its length, the diver must bring it to the surface for additional processing. The diver also drives wedges one after the other into cracks and open seams. It is recommended to pre-wrap the wedges with a thin layer of resin tow.
Having driven in the wedge or plug, the diver cuts or ties off the end and releases the ballast. If necessary, plugs and wedges are lined with resin tow and the leaks are coated with lard or special putty. To prevent them from falling out while the vessel is moving, strongly protruding wedges and plugs can be sawed off, which is best done 2-3 hours after installation, when the wood has swelled.
Application of semi-rigid plasters. Semi-rigid patches are placed on holes in most cases as a temporary measure to seal them by ship crews without the participation of divers. Semi-rigid plasters come in different designs; most often, the so-called mattress patch is used. It consists of soft cha-
sty - two layers of canvas between each other with a layer of resin tow - up to 200 mm thick. Boards 50-75 mm thick are attached to the soft part at intervals equal to the thickness of the boards, which is necessary to bend the plaster along the contours of the body. To fasten the boards, a layer of canvas is placed and nailed onto them, which is then sewn to the soft part. Two pieces are placed on top of the boards and secured with brackets steel cable with lights to which the under-keel ends are attached.
A mattress patch, like other types of soft patches, is applied to the hole from the deck at the under-keel ends. The diver's job when installing a semi-rigid patch is to ensure its correct location and fit to the hull, as well as the proper tightness of the under-keel ends. After installing the patch and securing the under-keel ends, the diver removes the ballast from the patch.
Installation of rigid plasters. Rigid plasters can be made of wood or metal; in the practice of emergency rescue work, wooden plasters are more often used, since the manufacture of metal ones is more difficult and time-consuming.
Wooden plaster - has rectangular shape and is made from boards according to the size of the hole, so that the plaster covers the entire hole. Depending on the size and depth of installation, the plaster is made from two or three layers of boards or bars, the thickness of the plaster is selected from the table. 6.
Table 6
|
Plaster thickness, mm, at insertion depth |
||||||||||
|
patch, m |
||||||||||
0.3X0.3 0.5X0.5 1.0X1.0 2.0X2.0 2.5X2.5 3.0X3.0 4.0X4.0 5.0X5.0
A two-layer plaster is made from boards of the required thickness pre-cut to the size of the hole. The first layer of boards is laid on level ground, bars are laid from them and pierced with nails, and the knocked down board is turned over. A piece of canvas is placed on the shield, which should be approximately 200 mm larger than the shield on each side. The canvas is painted with red lead over the area adjacent to the shield and covered with a second layer of boards, nailing them along the perimeter to fasten them to the first layer; the nails should be of such length that they pass through both layers and can be bent on the reverse side.
Resined tow is placed around the perimeter of the finished shield so as to form a dense roller 70-130 mm wide and 30-40 mm high. The flap is wrapped with the edges of the canvas protruding from behind the shield and nailed in such a way that a soft border is formed along the edges of the plaster. Holes for hook bolts are drilled in the finished plaster, staples are nailed to it to secure the ends and ballasted.
A rigid patch is applied to holes that do not have outwardly curved edges or indentations at the edges. Curved edges
divers cut off holes and protruding parts of the set using electric-oxygen or gasoline-oxygen cutting. Attaching the patch is the most important operation for sealing the hole. Firm pressure on the patch can be achieved using hook bolts and flap bolts, as well as hook ends and tie rods.
To attach the patch, hook bolts are pre-inserted into the patch around the perimeter of the hole. The number of bolts depends on the size of the patch and the conditions of its installation, but not less than one bolt with a diameter of 20 mm for every 0.5 m2 of patch area.
The ballasted patch is fed at the ends to the diver, he points the patch at the hole and inserts bolts into it. After the bolts are engaged, the diver, alternately rotating the wing nuts, ensures that the patch is pressed tightly against the body (Fig. 76).
If it is not possible to hook the hooks of the bolts onto the edges of the holes, you need to install pieces of pipes or profile steel from inside the body, onto which to hook the hooks of the bolts. IN difficult cases Fastening the patch with hook bolts is carried out simultaneously by two divers, one of whom works from inside the hull.
A bolt with a folding head at its end does not have a hook, but a folding bracket - a head 450-500 mm long, which, when the bolt is inserted into a hole, is located along it, and then turns perpendicular to hold the edges of the hole. This limits the use of flap bolts for installing small patches up to 0.5 m2 in area, except in cases where the hole is long length has a width less than the length of the hinged bolt head.
The process of installing a patch on one or more bolts
Rice. 76. Installation gesture-"
who the patch is: 1 - ship hull; 2 - patch; 3 - hook bolts; 4 - wing nut; 5 - soft side (wall)
with hinged heads is similar to installation on hook bolts.
The fastening of the patch on the keel ends and guys, inserted through the hole into the ship's hull, is done with the help of sheets, which are used to tighten the keel ends and guys after installing the patch in place.
Regardless of the method of attaching the patch, the diver must carefully inspect it around its perimeter in order to establish a tight fit to the hull. If leaks are detected, the diver must knock out the patch with tow using a wooden wedge. Later, when pumping water from the flooded compartment of the vessel, the diver observes the patch, identifies leaks in the water flow and eliminates them.
Placement of box-shaped patches. Box-shaped plasters - a type of rigid plasters - come in rectangular and shaped ones. Rectangular ones are installed on straight sections of the hull, when for some reason it is impossible to cut off the protruding edges of holes, and figured ones - on uneven contours of the ship’s hull, as well as when there are dents and bulges along the edges of holes.
A rectangular box-shaped plaster - a plaster-box - is made according to the measured dimensions of the holes, and a shaped one - according to templates taken during the inspection of damage to the ship's hull.
A box-shaped patch has a bottom and side walls, which are the same in height for a rectangular patch, but with curvilinear contours for a shaped patch, according to the template taken. To install a shaped plaster in places with a large curvature of the skin, the plaster is made with a bottom consisting of two parts, which are fastened at an angle of 90° to each other (Fig. 77).
The thickness of the bottom of the box-shaped plaster is selected depending on its size and placement depth in the same way as a simple rigid plaster, according to table. 6. The thickness of the side walls should be no less than the thickness of the bottom, but usually they are made large for ease of stuffing the soft roller.
The tightness of the bottom of the box-shaped plaster and its walls is achieved by laying lead-dyed canvas between the layers of boards or by subsequent caulking with tow.
Rice. 77. Box-shaped plaster:
1 - bottom of the patch; 2 - metal tires; 3 - pillow (cushion); 4 - shackle; 5 - walls; 6 - metal casing
To give the box plaster the necessary rigidity, especially for large sizes and high altitude walls, use metal tires.
To install a box-shaped patch, the same means can be used as for installing conventional rigid patches, however, due to the distance of their bottoms from the sheathing, long distance Hook bolts and flap bolts can be difficult to use. Therefore, box-shaped patches, especially curly ones, are more often installed using heel ends and guy wires.
Repairing damage to the hull using concrete has significant advantages over other methods, because It is distinguished by reliability, durability and tightness. Concreting makes it possible to repair damage to the ship's hull that would simply be impossible to achieve by other means. For example, practice has shown that in most cases, only concreting can restore the tightness of the flooded compartments of a ship sitting on rocks or rocky soils. Concreting also makes it possible to repair damage to hard to reach places of the vessel, for example, under the foundations of machinery and mechanisms, in the fore and after peaks and on the chines.
Concreting the water-flow areas of the building also has the advantage that this method can achieve absolute impermeability of the damaged areas, whereas other temporary seals may not provide this. With the help of concrete, you can repair any damage - from minor damage to rivet seams to large breaks in the bottom or sides.
Many years of experience and observations have shown that correctly performed baton sealing lasts a long time, is durable and often eliminates the need for immediate docking of ships.
To prepare concrete, sand, gravel, broken brick or, in extreme cases, slag.
The recipe and methodology for preparing concrete mixtures are given in the manuals on marine practice. Mechanical properties concrete based different varieties cement in the table.
Note. The numerator shows the strength when hardening in water, the denominator shows the strength when hardening in air.
There are 2 types of concreting: air and underwater.
In air concreting, the damage is covered with a metal sheet, around which formwork is made and filled with concrete.
When underwater concreting, the water flow is first diverted from the hole so that it does not erode concrete mixture before the mixture “sets”. To drain water, a drainage pipe is installed, which can simply be plugged after the concrete has hardened.
Concreting damage to the bottom, 2nd bottom, or deck is no different from concreting damage to the side.
Any concreting of any damage to the hull is a temporary measure, and when the vessel is docked or upon its arrival at the port, damaged connections are replaced or holes are welded. To ensure greater safety of navigation, sometimes, at the request of the Register, the concrete seal on the ship’s hull is scalded, i.e. enclosed in a steel box welded to the body. In this case, if possible, the crack itself or the broken seam in the ship’s hull is welded from the outside or from the inside.
The sheets forming the box wall around the concrete embedment, or cement box, are usually welded directly to the shell or frame of the vessel. Then all the free space of the cement box is filled with new mortar and sealed with overlay sheets on top.
If concreting is carried out in the port, then the concrete seal must be welded. A steel box with a tube welded into it is attached to the ship's hull, filled with coarse aggregate and concrete is laid on top with a steel sheet.
Various options concreting damage after preliminary sealing from the inside of the vessel in any way is shown below.
