Requirements for dismantling rubberized metal structures. Types of dismantling of metal structures. Types of dismantling of metal structures

Stairs. Entry group. Materials. Doors. Locks. Design » Plaster Requirements for dismantling rubberized metal structures. Types of dismantling of metal structures. Types of dismantling of metal structures

Requirements for dismantling rubberized metal structures. Types of dismantling of metal structures. Types of dismantling of metal structures

quite often found in the practice of repair and restoration activities. Removing the steel frame of a greenhouse that has served its purpose, or moving power line supports to a certain distance - work that must be properly planned and carried out.

Methods for dismantling metal structures

Depending on the specific goals and objectives, two methods are used:

1. Demolition of metal structureswithout subsequent restoration.
2. Dismantling of metal structuresfor the purpose of using it in a new location or using part of the previous metal structures for the construction of new structures.

The first method is used for one-piece structures made by welding or riveting, and the second - for prefabricated metal structures, parts of which are connected together using fasteners - bolts, pins, screws.

The choice of dismantling method is determined current state elements of the previous structure. For steel structures, the installation of which was carried out without preliminary anti-corrosion treatment of parts, such an assessment of the condition is associated with the presence and intensity of the processes of irreversible oxidation of the metal by atmospheric oxygen. For aluminum metal structures, an assessment of the residual strength and actual deformation of elements under operating loads is taken into account. It is often necessary to estimate cumulative wear and tear, since some elements of the metal structure may be made of concrete, wood or stone. In such cases, the degree of damage to parts at their joints is assessed.

Grade corrosive wear metal structure elements

The actual rate of metal wear due to corrosion in a normal air atmosphere ranges from 0.05-1.6 mm per year. Thus, the spread of data is quite large. Depending on the actual state of the metal structure during dismantling, a decision may be made either to completely destroy it by cutting it into pieces, or to dismantle it for the purpose of subsequent restoration. Therefore, a qualitative assessment of the condition of the metal steel structure determines not only the labor intensity of the work, but also the subsequent financial costs for the manufacture of a new element, which can be very significant.

Corrosion losses are estimated:

1. by measuring actual parameters cross section rolled metal;
comparison of the actual thickness of the metal element in its most critical places.
2. Theoretically possible method assessing the condition of a metal element by weighing it is not used in practice, since not all parts have initial drawings indicating their initial weight.

To measure dimensions, simple and accessible tools are used: calipers, depth gauges, micrometers, measuring clamps. In especially critical cases, as well as to determine the dimensions of parts in hard to reach places It is possible to use indirect assessment methods, which include radio wave and ultrasonic thickness gauges. Such devices are compact and reliable, differ high accuracy indications, and therefore may well be rented to assess the degree of wear.

For a comparative assessment of wear, the resulting size is compared with:

- the original value measured in an undamaged place (for example, in one that was constantly in an oil bath);
- passport value of the profile according to the data of the relevant GOST.

The accident rate of corrosive wear, at which the metal structure is subject to unconditional disposal, is more than 25%.

Tools for dismantling permanent structures

The most productive cutting of metal structures is carried out using gas cutters and hydraulic hand scissors. The largest elements of metal structures destroyed during dismantling are subsequently cut at metal bases using scrap alligator shears with a mechanical or hydraulic drive.

Specialized companies engaged in dismantling work also have specialized equipment. This includes:

diamond wire machines equipped with saws with diamond coating on the working part - such tools are used when dismantling deteriorated steel pipes;
portable bolt cutters - used when separating parts of a dismantled steel structure, to connect the elements of which fasteners were once used;
angle grinders used for disassembling parts that are located in hard-to-reach places in steel structures;
All of the above equipment, as a rule, does not have an electric drive, but is driven by internal combustion engines, which increases its autonomy.

During destructive dismantling, it is often used as auxiliary various lifting and transport equipment. For example, with the help of lifts, dismantling work can be performed at heights up to 18 m inclusive. And a number of crane and excavator designs allow the installation of hydraulic shears on their booms, which can be used to cut fairly massive building frame elements.

In case of a large volume of dismantling work involving the destruction of metal structures, shredders are installed on site, with which scraps of rolled steel can be cut and then compacted into smaller fragments.

Collapsible dismantling of metal structures

Unlike the previous method, the share of manual labor increases significantly here, since all elements must be disassembled into parts without losing their functional purpose. For the convenience of such dismantling, the entire product assembly is lowered onto the ground, and subsequent work is carried out there.

In order to successfully unscrew a bolt or other fastener exposed to atmospheric oxygen for a long time, you must:

- Assess the reasons preventing unscrewing (rust on fastener parts, their displacement from their original position or deformation of the base).
- Pour into the gap between the bolt shaft and the nut head any liquid that has a high penetrating ability (you can use regular kerosene, although there are safer substances, for example, WD-40). After some time, these media penetrate the gap and reduce the adhesion friction between the fasteners.
- If none of the above is at hand, you can try to unscrew the bolt by directing short and sharp blows with a chisel counterclockwise to the head of the product. In this case, it is necessary to periodically monitor the condition of the head so as not to cut off or deform this element of the bolt.
- To remove flush-mounted fasteners, you must use special tools- extractors. As a result of their use, a drill with a reverse thread is screwed into the bolt head, which creates an opposite torque, making non-destructive dismantling possible.

Organizational issues of dismantling metal structures

Considering the complexity of the work performed, it is necessary to adhere to safety rules:

- Do not carry out dismantling work at height without guardrails.
- Comprehensively assess the stability of the metal structure during its disassembly.
- Fence the danger zone on the ground with warning tapes or signs.

An important aspect of dismantling work is the organization of transportation of disassembled metal structures. Therefore, the team must include specialists in rigging work. At the place where it is performed the presence of cables, chains, ropes, hooks and other devices must be ensured to facilitate the transfer of dismantled elements by truck cranes or lifts to the bodies of cars and dump trucks. If necessary, it is also provided here special zones, equipped with scaffolds, loading platforms and fencing posts.

Structures based on metal structures are reliable, strong and durable, easy to assemble and several times cheaper than buildings made of brick and concrete. It is not surprising that the demand for such buildings is growing, and the layout of the urban landscape is expanding at an enviable speed with new modern structures.

If the service life of metal frame buildings expires or it is necessary to move the structure to a new location, dismantling of the metal structures is required.

When dismantling of metal structures is required

Dismantling of metal structures is the process of disassembling a structure into elements for the purpose of disposal or further transfer to a new construction site. Disassembly or demolition may be required different situations, For example:

the owner plans to change or expand the scope of activity;
the company needs to change the layout of the premises;
the company wants to change equipment and special equipment in connection with the launch of a new production line;
it is necessary to demolish the emergency room, hangar, building;
the need for reconstruction of a building, where partial dismantling of some elements is carried out - columns, beams, trusses...;
in order to optimize logistics, the warehouse needs to be moved closer to the place of production, etc.

Finally, if a building made of metal structures is temporary and was erected in advance with the purpose of its subsequent dismantling, it is also subject to disassembly.

In fact, there are many more reasons for dismantling metal structures of buildings, depending on the specifics, each case must be considered individually. But for this you will need to turn to professionals in your field; choosing them is not easy.

Who should dismantle metal structures?

The service of dismantling metal structures in Moscow and other regions is available to everyone, while disassembly and disposal/transfer to a new location must be carried out by specialists. It’s great if the company that carried out the installation also dismantles the metal structures. The complexity and duration of the parsing process in this case is reduced significantly.

Remember that demolition work is a complex and high-risk activity. A company that provides services for the dismantling of metal structures must own a fleet of special machinery and equipment, have a team of professionals, a production base and experience.

What equipment is needed for dismantling:

trucks for export;
truck cranes and equipment with a mechanical manipulator;
hydraulic lifts;
metal cutting equipment.

Among the employees it is important that there are:

expert appraisers;
team of carvers;
foremen;
slingers.

Make sure that the working personnel have permission and access to carry out this type of work!

Types of dismantling of metal structures

There are only two types, these include:

Demolition of metal structures with further disposal (sale for scrap metal).
Dismantling and transportation to a new location for re-installation.

In the second case, the reliability and durability of the building during its repeated construction will depend on the quality and professionalism of the work performed.

For certain moments it may be carried out partial dismantling structures, where element-by-element disassembly, winches and cranes are often used.

How dismantling is carried out: main stages

The specialists are faced with a difficult task - they must carefully demolish the building without touching neighboring buildings, and in the case of repeated construction, they must disassemble the load-bearing structures and massive elements as carefully as possible, reliably preparing them for further transportation.

The technology for dismantling structures is necessarily based on planning the work, which includes expert review(diagnostics) of the condition of structures and drawing up a work project in accordance with the contract. If we consider this event step by step, we get the following diagram:

Specialists study the construction site, inspect the structure, assess the condition of metal structures. The type of special machinery and equipment that will be used is determined.
Carrying out dismantling work in compliance with all safety standards and regulations. Dismantling begins with dismantling the enclosing structures - sandwich panels, corrugated sheets, gates, doors, etc. The corrugated sheets and panels are neatly folded for further transportation and assembly. Keep in mind that structures made from metal structures are not Lego sets; it is impossible to disassemble them down to the last detail without damage. Load-bearing frame elements and large parts are dismantled last without damage, but such as roofing or sheathing materials will have to be replaced.
Cleaning of the dismantling site and transportation - the site of the former building is thoroughly cleared of debris and waste, metal structures are transported for further disposal or installation.

Compliance with all these points guarantees short time, quality of dismantling and removal of metal structures.

Possible problems during disassembly

Let's look at four main problems and methods for solving them.

Carrying out work in cramped conditions

This problem is common in densely populated areas with dense buildings. Careful planning will help here, which eliminates the possibility of collapse on neighboring buildings.

Dismantling at height

Two-story and higher structures, long-span large structures - a service for dismantling metal structures, which companies often place in a separate category. This is primarily due to the complexity of the work. Here, not only high-tech equipment can be used for high-rise buildings, but also involve a helicopter and industrial climbers.

Cutting metal structures

Large elements that are planned for demolition have to be cut, which carries danger and injury. Here it is important to carry out additional preparation, use of hooks and manipulators.

Transportation of structures

During transportation, metal structures can easily be damaged in such a way that their reuse will no longer be possible - the job is a failure. To avoid such a situation, it is important to correctly select transport that would correspond to the dimensions and dimensions of the building elements.

Features of pricing for the dismantling of metal structures

The price of dismantling metal structures is influenced by many factors:

complexity and volume of work carried out;
dimensions of the demolished structure;
type of metal structures;
level of time spent;
the need to attract heavy special equipment and a brigade group;
height of buildings;
accessibility of access to the structure and location;
the need for waste disposal, transportation, etc.

For the exact cost of dismantling metal structures, it is necessary to draw up an estimate after a preliminary inspection construction site, which is scheduled for demolition.

Dismantling metal structures requires special care and extreme caution. In most cases, dismantling work is carried out at non-standard sites, in cramped conditions or on high altitude. At the same time, many metal structures are suitable for recycling or can be effectively recycled, so they must be disassembled element by element with maximum preservation of the integrity of the parts. After any type of dismantling of metal structures, it is necessary to organize the removal of construction waste.

Features of dismantling metal structures

Dismantling of metal structures must be carried out taking into account the physical condition of the structure, the characteristics of its structural elements, bearing capacity and purposes of dismantling. In most cases, when dismantling metal structures, a combined approach is used - demolition of the structure followed by careful manual disassembly of metal elements.

Lightweight metal structures are often reused. Therefore, dismantling of such structures must be carried out in accordance with technical documentation in strict sequence. After disassembly, small elements of metal structures are packed in boxes, and large parts are packed in protective film.

Selecting the type of dismantling of metal structures

When choosing the type of dismantling of metal structures, craftsmen compare various options to find the most optimal solution. It is not uncommon for a structure of smaller dimensions to require more effort for dismantling than a heavier and larger one. This happens as a result of the fact that the cost of metal for a more compact design can be much higher, so its disassembly must be done manually.

Types of dismantling of metal structures:

Destruction of the structure. With this type of dismantling, the metal structure cannot be reused, and the scrap metal is sent for recycling. Dismantling is carried out quickly.
Step-by-step dismantling of metal structures. In the process of dismantling structural elements retain their original integrity, which allows them to be reused. Disassembly is done manually or using equipment. Special equipment is used to load and remove parts of metal structures. Such dismantling is more expensive and takes more time.

The type of dismantling is selected at the stage of preparation and determination of the sequence of work to be carried out. The peculiarity of dismantling metal structures is that the production is almost completely waste-free. After dismantling or demolishing the object, the condition of all structural components and their suitability for further use is assessed. As a result, structural parts are reused or recycled.

*information is posted for informational purposes; to thank us, share the link to the page with your friends. You can send material interesting to our readers. We will be happy to answer all your questions and suggestions, as well as hear criticism and suggestions at [email protected]

Great attention is paid to the quality of work on the installation of metal structures, since the degree of safety of the facility during operation depends on them. However, the dismantling of technological, temporary, or metal structures that have expired their warranty period also requires no less attention. As a rule, dismantling is carried out by the same organizations that once installed the building or equipment. This is quite justified, since it is much easier for the specialists who carried out the assembly to dismantle these metal structures.

If previously the need to dismantle large metal structures did not arise often, today the vast majority industrial buildings, lifting mechanisms and obsolete technological equipment needs replacement. There are three main methods of dismantling:

Equipment is cut for scrap metal. As a rule, these are spent chemical equipment or rusted structures of workshops and hangars;
The equipment is being cut to make room for the installation of more modern equipment, but a significant part of the metal structures is planned to be reused in non-critical areas;
The equipment is dismantled for subsequent installation and use in a new location.

Regardless of the purpose of dismantling, metal structures must be dealt with according to a carefully developed plan. The most time-consuming and expensive part is dismantling the equipment to move it to a new location. With this method, cutters are practically not used, and the installation team tries to dismantle all easily removable elements in order with minimal damage, carefully numbering and packaging them. Then, using various lifting mechanisms, large-sized elements are dismantled.

The only elements that are cut off with this dismantling method are various stairs and non-removable protection elements, since it is cheaper to weld them in a new place. Most often, various crane equipment, process tanks and various auxiliary structures are dismantled in this mode.

If the customer wishes to retain part of the metal structures as a material for further use, he must, together with a representative of the installation organization, draw up a list of the material to be left. During dismantling, disassembly can be done in many ways, so employees will, if possible, cut the metal to specified dimensions.

When completely dismantling a building or technological equipment for the purpose of scrapping it, the main task is to ensure the safety of workers and the maximum speed of work. Despite the apparent simplicity of dismantling buildings and large-sized technological equipment, this work can only be performed by specialists, since it is impossible to predict how multi-ton equipment that has expired will behave during disassembly.