Bellows expansion joints

Bellows expansion joints made of of stainless steel designed to compensate for various displacements according to specified parameters. In order to achieve maximum service life, resistance to pressure, as well as reliability and strength, care should be taken when handling expansion joints, as well as during their storage and installation. Similar caution is exercised when following the rules below.

Storage and transportation of bellows expansion joints

If handled incorrectly or carelessly, the bellows expansion joint may be damaged or deformed, which in turn will negatively affect its technical characteristics.

The bellows compensator cannot be subject to mechanical damage, as well as damage caused by exposure to humidity, water, soil, sand, chemicals, etc.

Transportation fittings, tightening joints, cardan suspensions (hinges) cannot be used to move the bellows compensator as lifting loops. Also, bellows expansion joints cannot move in a way that could cause mechanical damage bellows (for example, lift the expansion joint by the bellows).

The bellows compensator must be stored on a straight plane indoors; if this is not possible, then under the protection of a waterproof coating.

Bellows expansion joints cannot be placed on top of each other or stand very close to each other.

If the ends welded to the bellows expansion joint (welded connection) due to their weight subject the expansion joint to deformation, they must be supported from below using wooden beams.

The service life of the bellows expansion joint provides that the bellows expansion joint will under no circumstances be subject to mechanical or temperature influences other than those provided for during the design. Bellows expansion joints can only be installed in pre-designated locations within pipe networks. If the installation rules are not followed, the service life of the bellows compensator, as well as its ability to compensate for pressure, can be significantly reduced, which in turn will lead to damage in the networks.

Preparation for installation of bellows expansion joints

The pipe to which the bellows compensator will be connected must be checked before installation for any inaccuracies. Identifying inaccuracies is important, as this will eliminate the overload of the bellows compensator caused by the desire to balance these inaccuracies. The following must be checked:

Was the bellows compensator damaged during transportation? Damage may include dents or bulges, damage to transport fittings, signs of water on the compensator (signs of corrosion), etc.

Does the distance between the ends of the pipes to which the bellows compensator will be mounted correspond to what was provided?

Pipes to which it is connected bellows expansion joint, must be firmly secured using fastening points and sliding supports.

Support points must be designed in such a way that they are able to compensate for reaction forces and other influences.

The bellows compensator can only be mounted between two fixed supports(only for axial and shear expansion joints).

The increase can only occur in accordance with the parameters of the bellows compensator.

The bellows expansion joint cannot be subject to twisting or stretching.

Fixed and sliding supports must be placed on the connected pipe in such a way that:

The bellows expansion joint was not subject to stress caused by the weight of the pipe.

The pipe did not sag between the fixed and sliding supports.

Sliding support location

The distance between the bellows expansion joint and the first support cannot exceed 4 x pipe diameter.

The distance between the first and second support cannot exceed 14 x pipe diameter.

The distance between the remaining sliding supports cannot exceed 21 x pipe diameter.

The distance must be reduced in cases where pipe stabilization is required.

All kinds of protective clips and safety fittings must be removed after installation of the entire pipe system. Elements to limit the movement of the compensator, such as tightening, cardan suspensions (hinges), are not eliminated, since they are an integral part of the compensator.

In case That is, if the bellows compensator is equipped with an arrow, during installation it is important to make sure that the arrow points in the same direction as the direction of the conductive medium flowing through the pipes.

The expansion bellows must be protected from welding plaster (during welding).

The expansion bellows must not come into contact with working tools or lifting devices when installing it.

The length of the bellows compensator must correspond to the length intended for installation. Thus, the bellows expansion joint must be installed in the length that it has at the time of delivery.

The expansion bellows cannot be used for moving, hanging, storing, etc. compensator. These actions should only be carried out using welding or flange connections, or a protective cage.

Any welding or screwing of the bellows expansion joint must be carried out in such a way that the bellows is not damaged.

The bellows compensator, which is subsequently subject to insulation and does not have external protective fittings, must be equipped with external protection in the bellows area. Such protection will prevent insulating material got into the bellows coils over time and thereby interfered with its normal functioning.

Precautionary measures

Avoid falling or being hit by the bellows.

Do not use cleaning agents containing chlorides.

Do not use steel wool or brushes to clean the bellows.

Do not forcefully twist one end of the expansion joint so that it aligns with the bolt holes in the corresponding pipe. Conventional bellows are not designed to absorb twist.

Fastening points and fastening systems must be accurately calculated.

After installation

Before the completed pipe system is put into operation, it is necessary to visually inspect everything technical details. Many years of experience show that if this advice is followed, installation is usually successful.

Check whether the bellows expansion joint was damaged during installation or handling.

Check the correct installation of the entire system, and especially the support points, in accordance with the design documentation and installation instructions.

Check the correct installation of the bellows compensator throughout the system for location and correct connection.

Check the correct installation of the bellows compensator in the direction of the conductive medium in the system.

Check whether the bellows and other moving parts of the compensator are free of foreign materials.

Check that all packaging materials and protective fittings have been removed from the bellows expansion joint.

If a system is designed for a light conductive medium (gas) and must be tested with a heavier conductive medium (water), check that all necessary measures precautions for safe operation.

bellows expansion joint- compensator A device consisting of a bellows (bellows) and fittings, capable of absorbing or balancing relative movements of a certain magnitude and frequency that occur in hermetically connected structures, and conduct under these conditions... ...

bellows expansion joint- 3.5 bellows compensator: A device consisting of a bellows and fittings, capable of absorbing or balancing relative movements of a certain magnitude and frequency occurring in hermetically connected structures, and conducting in these... ... Dictionary-reference book of terms of normative and technical documentation

axial bellows expansion joint- Bellows compensator that performs its functions under conditions of axial impact of the structures being connected. [GOST 25756 83] Topics bellows General terms types of bellows expansion joints EN axial bellows expansion joint DE Axialbalgkompensator… … Technical Translator's Guide

rotary bellows compensator- Bellows compensator that performs its functions under conditions of angular impact of the structures being connected. γ = γ1 + γ2 [GOST 25756 83] Topics bellows General terms types of bellows expansion joints EN angular bellows... ... Technical Translator's Guide

balanced universal bellows compensator- A universal bellows expansion joint that does not load the connected structures with expansion force. [GOST 25756 83] Topics bellows General terms types of bellows expansion joints EN pressure balanced expansion joint DE Universalbalgkompensator,… … Technical Translator's Guide

shear bellows expansion joint- A bellows compensator that performs its functions under conditions of shear of the connected structures perpendicular to the axis of the compensator. [GOST 25756 83] Topics bellows General terms types of bellows expansion joints EN lateral bellows expansion joint… … Technical Translator's Guide

universal bellows expansion joint- Bellows compensator, which performs its functions under a combination of shear, axial and angular effects of the connected structures. [GOST 25756 83] Topics bellows General terms types of bellows expansion joints EN universal bellows expansion joint ... Technical Translator's Guide

rotary-axial bellows compensator- [GOST 25756 83] Topics bellows General terms types of bellows expansion joints EN angular axial bellows expansion joint DE Axial Angularbalgkompensator FR compensateur ondulé angulaire/axial … Technical Translator's Guide

shear-rotary bellows compensator- [GOST 25756 83] Topics bellows General terms types of bellows expansion joints EN lateral angular bellows expansion joint DE Lateral Angularbalgkompensator FR compensateur ondulé latéral/angulaire … Technical Translator's Guide

Angular shift compensation ... Wikipedia

Question to a specialist

A bellows axial compensator (ABC) is a flexible element used primarily to compensate for water hammer and thermal axial deformation of pipelines for any installation method. Feature of this device is the design; The compensator is made of one or more flexible corrugations (bellows) made of high-quality stainless steel. Components are produced by cold rolling, which, unlike the hydraulic method, provides the product with special reliability and durability. Due to temperature changes, the straight section of the pipeline receives a slight increase in length, as a result of which other deformations occur that can quickly damage even new pipes. The compressor corrugations are flexibly deformed and absorb changes in the length of the section, depending on the compensating ability of the device.

Installation of bellows axial expansion joints is carried out using various working fittings. The equipment is connected by joining threaded fragments, welding pipes or flanges. Design features consist in the production of compensators with protective casing, internal screen and travel limiter, depending on the general technical characteristics of the equipment and the compensating capacity required for them. Before delivery to the sales market, modern bellows expansion joints undergo strict control for compliance with standards high standards, subjected to destructive and hydraulic tests.

Mandatory parameters for selecting a bellows axial compensator:
- The magnitude of the working stroke (millimeters, angular degrees).
- Nominal internal diameter.
- Maximum permissible load pressure.
- Design features and type of installation.
- Material of the product.
- Working temperature pipeline or heating network.

Bellows expansion joints are used in construction and industry, and can also serve as components for tanks, motors and pumps in production. They are convenient for installation and maintenance work and can withstand maximum operating pressure to which the pipeline is exposed are reliable and easy to maintain.

The Engineering Company "Kronstadt" is official distributor compensators Duro Dakovic in Russia. Our specialists will help you select a standard bellows axial expansion joint, or order its development on an individual request in accordance with special requirements technical characteristics equipment.

Bellows expansion joints are small in size, can be installed anywhere in the pipeline using any method of laying it, and do not require the construction of special chambers or maintenance during the entire service life. Their service life, as a rule, corresponds to the service life of pipelines.

The use of bellows compensators ensures reliable and effective protection pipelines from static and dynamic loads arising from deformations, vibration and water hammer. Thanks to the use of high-quality stainless steels in the manufacture of bellows, KSO are able to work in the most severe conditions with temperatures of working media ranging from " absolute zero» up to 1000°C and can withstand operating pressures from vacuum to 100 atm, depending on the design and operating conditions.

Depending on the purpose and conditions of use, various designs of bellows expansion joints are used, which are various combinations of bellows, connecting and limiting fittings, guide pipes and protective covers.

The main part of the axial bellows compensator is the bellows - an elastic corrugated metal shell that has the ability to stretch, bend or shift under the influence of temperature changes, pressure and other types of changes.

They differ from each other in such parameters as dimensions, pressure and types of displacements in the pipe (axial, shear and angular). Based on this criterion, bellows expansion joints are divided into axial, shear, angular (rotary) and universal.

The bellows of modern expansion joints in a casing consist of several thin layers stainless steel, which are formed using hydraulic or conventional pressing. Multi-layer expansion joints neutralize the impact high pressure and various types of vibrations, without causing reaction forces, which in turn are provoked by deformation.

Corrugated metal axial expansion joints in a casing are made of longitudinal welded pipes. These compensators are designed and manufactured in full compliance with EJMA standards and according to temperature and pressure indicators.

Compensator in casing for heating and water supply systems

Application:

Expansion joints in a pipe casing, which are one of the types of axial bellows expansion joints, are an expansion that is used to absorb noise and resulting vibration. The expansion, being divided into parts inside the pipeline systems, is isolated using fixed points. Thus, the movement that occurs in the vibration area is absorbed by the pipe expansion joints that are used inside the area.

Today at multi-storey buildings common, expansion and contraction that occur due to temperature changes in the columns of heating equipment lines and hot water, can lead to pullout of the tooth, rupture of parts of the connection, noise, and irregularities in the pipes.

Advantages of axial expansion joints in a casing from Ayvaz:

They have a multi-layer bellows with an internal guide sleeve.

Prevent expansion in column pipes, noise, disruption and distortion.

Provides energy savings to prevent pressure loss.

Reduces labor costs, although preparation and installation is very fast and very simple.

Column lines can be easily used in rooms, corridors, and offices. At the same time having an aesthetic appearance.

In columns heating equipment temperature 90*C/70*C, on each floor the expansion is approximately 3mm. In the column lines of a 7-story building (21m), in combination with expansion, ventilation and the main line, expansion, ventilation and main pipe when they are concentrated in the lines of the columns of a 7-story building (21 m), bends may form.

Axial expansion joints for pipes from Ayvaz, have a multi-layer bellows, which are necessary for use in column lines of buildings higher than 7 floors, 1 expansion joint is used at most for 30 m (1 expansion joint for 10 floors.)

Zo meters - this is the most long distance between two fixed points.

In a location that is close to the ceiling, floor, between two fixed points, KSOs are mounted in a St. Petersburg casing, for pipes from Ayvaz.

Material structure:

Stainless steel according to DIN17440; connecting elements are made of carbon steel, external protection Made from decorative-looking aluminum.

Connections:

Rotating Flange - Welding Connection

Nominal diameter - DN15 (1/2") - DN100 (4")

Pressure indicators:

Max. up to 16 bar (operating pressure depends on nominal diameter and operating temperature)

Temperature range - According to the structure of the material: from -20*C to 90*C.

Axial expansion joints, are used to absorb thermal expansion along the axis of the pipe. Pipe systems the inside was divided into parts using fixed partitions to prevent heterogeneous expansion and provide insulation. Thus, the movement that occurs in the expansion area is absorbed by the metal bellows expansion joint used in this area.

Axial compensators in casing, manufactured to 30 and 60 mm standards, can be produced upon special request with different indicators extensions. Liner materials are used to interrupt the connection between the bellows and the liquid and regulate the flow. Using the flow temperature and bellows materials, which are associated with pressure, the number of floors and wall thickness are developed.

connections:

rotating flange

fixed flange
with welding connection

Structure:
Design and production: made according to EJMA standards. Pressure and temperature indicators in accordance with DIN 2401 standards.

Material structure:
corrugations and inserts are made of stainless steel in accordance with DIN 17440 standards, connecting elements are made of stainless or carbon steel. Other materials can be produced upon request.

Nominal diameter - DN 25(1") - DN 2600 (104")

Pressure indicators

Axial expansion joints in casing, are manufactured according to the standard pressure category PN16, compensators in which it is necessary to achieve higher pressures are manufactured according to special design. Dependent on operating pressure, nominal diameter and operating temperature.

Temperature range:

In accordance with the structure of the material - from 196 *C to + up to 600 *C

Application:

All types of thermal equilibrium and mechanical expansion of the pipeline.