Temperature changes caused by seasonal climate change or changes in the characteristics of the transported medium, as well as dynamic loads created by operating equipment, can cause the pipeline to shift relative to its original position. Even if it is relatively small, regular loads significantly increase the risk of damage. pipeline fittings, supports and other elements of the highway. In this case, the use of a vibration insert or vibration compensator can eliminate the negative impact.
What is a vibration insert and where is it used:
A vibration insert, or flexible insert, is a type of industrial pipeline fittings designed to compensate for lateral, angular and axial displacements of the pipeline. It consists of an elastic middle part, made mainly of reinforced heat-resistant rubber or a similar elastic polymer, as well as two connecting metal (most often steel) elements. The latter can be presented in the form of a threaded shank or flange - this depends primarily on the diameter of the pipeline for which the product is intended.
In high-quality vibration inserts, the elastic element has a multi-layer structure. Its inner layer has no seams and is made primarily from materials that can be used in systems with clean water. This is followed by a reinforcing layer of rubber-impregnated synthetic fabric (nylon), and another layer of rubber is applied on top of it, providing resistance to ultraviolet radiation and ozone. As for the connecting parts, they are coated with an anti-corrosion layer, which provides protection from external influences. The flanges and couplings do not come into contact with the medium.
The flexible insert is mounted on sections of the pipeline that are most susceptible to spatial movements and vibrations, for example, located next to compressors, pumps and other process equipment. Most often, the above-mentioned units themselves stand on special supports that compensate for vibration, but it is transmitted to the main line. Also, the installation of vibration inserts is justified in cases where it is necessary to ensure the possibility of slight displacement of the pipeline due to temperature effects or a change in direction. But it is not allowed to use vibration inserts to correct errors made during the installation of the pipeline - they should not be under load in their original position. Certain restrictions also exist for transported media.
Standard vibration compensators can be installed on pipelines intended for transportation:
- cold water;
- hot water with a temperature not exceeding 100º C;
- non-concentrated (up to 10%) acids;
- organic and inorganic alcohols;
- solutions of salts and alkalis.
Their use in systems for transporting petroleum products, very hot and aggressive environments is unacceptable. This is primarily due to the low resistance of the elastic central part to them. For the same reason, this fitting cannot be used on highways running indoors, the conditions in which can destroy the outer layer of the insert. In such cases, special-purpose vibration inserts are used that are resistant to these environments (if they exist) or more expensive metal vibration compensators.
Selection of vibration compensator and installation features:
When choosing a vibration compensator for a specific object or area, you must first take into account the following points:
- type and temperature of the transported medium;
- the nature of the applied loads (compensated deviations);
- pipeline diameter;
- possible mechanical and chemical external influences on the reinforcement.
Some of the above factors may affect not only the type of product used, but also the installation features of the vibration insert. In particular, in some cases it is advisable to use elements that limit the possibility of its deformation: restrictive rings, control rods or special rods.
In order for the vibration insert not only to work effectively, but also to serve for the expected period, it is necessary to strictly comply with all the requirements regarding their installation. In particular, a sliding or movable support must be installed on one side of the flexible insert, and a fixed one on the other. You should also avoid contact with the flexible part of the insert of bolts, studs and other fasteners, and place the nuts on the outside of the flange. To install vibration compensators, it is preferable to use collar flanges, or carefully clean the flat weld seam to avoid damage to the connecting element area of the elastomer when screeding.
The need to use vibration inserts when connecting units to the pipeline is due to safety measures to prevent factors that destroy various network elements or lead to increased noise levels, and in order to galvanic isolation of the pipeline and protection of equipment from destructive mechanical effects. In addition, use similar devices necessary in earthquake-prone areas and when there is a danger of movement of the soil on which the equipment is installed, provided that the displacement does not exceed permissible values (for higher loads it is more advisable to use special devices based on bellows expansion joints). The requirements of SNiP 14.15 state: “At the inputs in front of the measuring devices, as well as at the points where pipelines are connected to pumps and tanks, it is necessary to provide flexible connections that allow angular and longitudinal movements of the ends of the pipelines.” Flexible pump inserts must be installed when operating pumps with motors greater than 11kW (lower motors may also cause unwanted noise and vibration).
The rotation of the motor and pump rotors, as well as the conductive fluid in the pipeline, cause noise and vibration. The degree of impact on equipment and the surrounding area depends on how correctly the calculations were made and the state of the remaining elements of the system. The most effective way to dampen vibration and reduce noise levels is to use vibration mounts on foundation slab units and connecting the pipes to the pipeline through rubber vibration inserts. This allows you to maintain stable operation of the pumps, reduce the load on fragile cast-iron structural elements, and also minimize vibration and noise. In addition, installing compressors and pumps on vibration supports without using rubber inserts on the suction and pressure pipes leads to the equipment hanging on the flanges and, as a result, destruction of the housing of the units and pipeline fasteners. Vibration compensators for pumps help protect equipment and pipelines from vibration, as well as prevent system resonance.
Depending on the material of the flow part, a vibration insert for the pump can be used in systems transporting hot and cold water, air, acidic environments with a concentration of less than 10%, organic and inorganic alcohols, solutions of salts and alkalis, as well as bulk products. The permissible nominal pressure can range from 1.0 to 1.6 MPa, and working temperature from -40С to +90/110С (depending on the model).
The price of products remains quite low, thanks to timely deliveries and keeping the most popular sizes in stock.
Good afternoon, dear readers of the blog site
In the “Accessories” section we will look at vibration inserts. In our modern life, pumping equipment is used very widely and variedly. The main purpose of anti-vibration inserts is to prevent the transmission of vibration, noise and mechanical stress through pipeline systems; they are also used as compensators for various deformations (temperature, linear and angular). They are used in heating and air conditioning systems to compensate for thermal elongation and compression of pipelines, in water supply systems to prevent the transmission of mechanical vibrations from system pipelines, as well as to protect pumping equipment and pumping stations from the mechanical impact of pipelines connected to them. Compensators are also designed to reduce or prevent. Their use significantly increases the service life of the system as a whole. By method of connection to the system vibration inserts or compensators are divided into coupling and flange. The working medium in pipelines where coupling and flange vibration inserts are used can be water, steam, air, gas, oil products, and food products.
Technical parameters and materials
- Working pressure: Ru=16 bar.
Connection diameter coupling vibration inserts: DN 15-50 mm
Materials used:
- The inner layer of the bellows is EPDM;
- The bellows frame is a nylon fabric cord;
- The outer layer of the bellows is EPDM;
- The coupling connection is made of steel.
Parameters of coupling vibration inserts:
- Operating temperature: +110°C;
- Working pressure: Ru=16 bar.
- Working pressure: DN 32-600 – PN=16 bar.
- Working pressure: DN 700-1200 – PN 10 bar.
Connection diameter flanged vibration inserts: DN 32-1200 mm
Materials used:
- Connecting flanges – steel;
- Bellows rubber – EPDM;
- The bellows frame is steel cord – carbon steel; nylon cord is a synthetic fiber.
Device and design
Structure and design of compensators (Fig. 1)
The bellows, vibration insert or compensator has a complex, multi-layer structure. It consists of an outer (Pos. 1), internal (Pos. 3) layers and a frame (Pos. 2). The inner layer is a tube, seamlessly made of rubber, extending beyond the beads of the compensator. Direct contact with the environment is carried out precisely by the inner layer. It also serves as protection for the compensator frame from the effects of adverse environmental conditions. An important condition in the production of vibration inserts, is right choice elastomer, either natural or synthetic. Both of these materials have good properties, they are resistant to liquid or gaseous media, ranging from plain water to sulfuric and hydrochloric acids dissolved in it. The frame is the elastic part of the rubber compensator, which consists of several layers of very high-quality synthetics, for example, nylon. A layer of fabric is impregnated in the frame with mixtures of synthetics or rubber. This was done in order to give them flexibility and mobility. The outer layer of the frame protects the compensator from the negative effects of the external environment and ultraviolet rays. To connect a compensator or vibration insert to equipment and pipelines, rotating flanges (Pos. 4) PN 10 or PN 16 are used, and American flanges are used for coupling connections. Flanges are made of carbon steel.
Installation and operation
During installation vibration inserts or compensators It is necessary to pay attention to the following:
- The inlet and outlet pipelines must be centered and secured. Expansion joints must not be used as a supporting structure.
- The maximum compression of the rubber compensator should not exceed 5 mm.
- Twisting of the compensator is not allowed.
- The pipelines from the rubber compensator must be secured at a distance of at least three pipeline diameters.
- The mounting bolts must be installed without direct contact with the rubber. Installation order: the bolt is installed on the compensator side, and the nut on the pipeline side. In case of operation of vibration inserts in systems with increased loads on pipelines, it is used set of rods, protecting compensator - vibration insert from exceeding the permissible value of stretching or twisting.
- Simultaneous operation of the expansion joint in tension and torsion is prohibited.
- In case of welding work the rubber part of the compensator must be protected.
- It is prohibited to paint compensators or vibration inserts or cover them with a layer of insulation.
Vibrating inserts cannot compensate for misalignments that arise during pipeline installation. The suction and pressure pipelines must be equipped with appropriate supports, mounted as close as possible to the pump. The counter flanges must be laid relative to the pump flanges in such a way as to prevent any transfer of voltage from them to the pump, as this can lead to damage to the pumping equipment. Compensators should be installed directly from the pump at a distanceequal to one to two nominal flange diameters, both on the side of the suction pipeline and on the side of the pressure pipeline. This will avoid the formation of turbulent flow in the compensators and creates optimal conditions when absorbed and will create minimal losses pressure in the pressure pipeline. At high water flow rates (more than 5 m/s), vibration inserts should be installed bigger size in accordance with the diameter of the pipeline. For flanges with a diameter larger than DN 100, expansion joints with limiting straps must always be used. In (Fig. 2) an example of installation of vibration inserts
To extend the service life of pipelines, it is necessary to use elastic vibration inserts or compensators. They compensate for changes in the length of pipes during their expansion or contraction, as well as possible ruptures of pipelines as a result of temperature changes, pressure changes, and the presence of various vibrations in pipelines. For optimal performance pumping equipment, and in order to minimize noise and vibration, it is necessary to provide ways to dampen vibration from the pump. These methods must be used without fail if pumping equipment is operated with electrical power over 11 kW. Although it is likely that engines with lower power can also create unwanted noise and vibration. To reduce these consequences, vibration inserts and vibration supports are used. Vibration inserts have good soundproofing properties; they absorb and reduce noise that is inevitable during the operation of pumping equipment, and are also resistant to hydraulic shocks that occur during pump operation. Vibration mounts are designed for passive and active vibration isolation of pumping equipment, as well as for height adjustment when installing pumps according to level. To compensate for pipeline movements during shifts, they are used shear expansion joints. They have limit rods designed to protect the vibration inserts from damage. You can install limit rods in both compression and tension. These compensators can be used very long time, since due to this design the thrust force is not transmitted to the equipment.
If operating conditions are observed, vibration inserts do not require constant technical care or repair. Periodically, it is necessary to carry out technical inspections to ensure there are no leaks, and, if necessary, tighten the fastening bolts or coupling connections.
Thank you for your attention.
The product catalog of Tecofi, the largest European company for the production of pipeline fittings, is represented by metal expansion joints and elastomer expansion joints, which protect the pipeline from deformation due to vibrations and exposure to temperatures. The noise-absorbing and vibration-absorbing ability is provided by the elastomer from which the body of this Tecofi compensator model is made. Elastomer is an elastic material with highly elastic properties. The EPDM bellows, used as a sealing and sensing element, has high wear resistance to thermal and mechanical influences, which ensures reliable operation throughout the entire service life. The design of the bellows allows the expansion joint to change under the influence of longitudinal, transverse and angular bends. The internal reinforcement is made of steel. The connection to the pipeline is flanged, the flanges are made of galvanized carbon steel. The product lifespan is at least 100 thousand opening-closing cycles. The tecofi anti-vibration compensator is available in various standard sizes.
Tecofi vibration insert
For proper operation of pipeline systems, along with compensators, anti-vibration inserts are used, which reduce vibration and various noises. Tecofi vibration insert consists of special rubber, which has high heat-resistant qualities. The ability to interact with working media such as compressed air, water in the temperature range from -10°C to + 110°C is ensured by the elasticity and strength of the material. The Tecofi vibration insert can also act as a compensator for various movements in the event of disturbances in the pipe system, thereby ensuring additional protection compensator.
It's all about their design features:
- The elastic element of the flexible insert is maximally resistant to aggressive environments. It is not harmed by the constant pressure of hot water, and even after long use the element will not lose its functions;
- compensators are flexible enough, which allows them to successfully restore their shape after mechanical stress. In addition, the flexibility allows expansion joints to be installed in pipelines with little misalignment;
- Are the pipes exposed to shock loads, vibrating and making a lot of noise? All these problems will be eliminated after installing a compensator that successfully resists hydraulic shocks;
- heat resistance - flexible inserts are made of heat-resistant synthetic rubber of a special composition;
- light weight, making them very convenient to transport, and the installation process will not cause difficulties.
Flexible inserts will increase the service life of pipes
A flexible insert, also called a vibration damper, is an element whose main purpose is to reduce or completely eliminate noise. In addition, these parts eliminate vibration, absorb hydraulic shocks and compensate for displacements, shears and thermal elongations.
All these factors make vibration compensators indispensable in pipelines - they are installed in water and gas supply systems, air conditioning, etc. As a result, the service life of pipes increases significantly.
Quality assurance
ADL guarantees that all flexible inserts purchased from us will perform their functions as accurately as possible - the products have a GOST P certificate of conformity.
Installing a vibration compensator will give you confidence that the pipes will not fail at the most inopportune moment. You will save a lot of money on repairs,
and also eliminate the need to spend time inspecting pipelines too often. With us you will receive high-quality service support, as well as a guarantee for all purchased goods.
