The pipeline compensator is mainly used to compensate for the thermal expansion and contraction caused by the temperature change of the pipeline. If the pipe does not expand or contract completely freely when the temperature changes, thermal stress will be generated in the pipe. This stress must be considered in the design of the pipe, otherwise it may cause the pipe to rupture, affecting the normal production. As an important part of pipeline engineering, the compensator plays an important role in ensuring the long-term normal operation of the pipeline.
First, the pipeline compensator introduction:
Pipe compensator is divided into metal corrugated compensator, non-metallic compensator, sleeve compensator, square compensator and so on. Metal corrugated compensators and non-metallic compensators are common in use.
1. The metal corrugated compensator consists of bellows (an elastic element) and end pipes, brackets, flanges, pipes and other accessories that constitute the working body. It belongs to a kind of compensation component. The effective telescopic deformation of the bellows of the working body is utilized to absorb dimensional changes caused by thermal expansion and contraction of pipelines, pipes, containers, etc., or to compensate axial, lateral, and angular displacements of pipelines, conduits, containers, and the like. It can also be used for noise reduction and vibration reduction. Widely used in modern industry.
2. The non-metallic compensator can compensate the axial, lateral and angular displacement of the pipeline. It has the characteristics of no thrust, simplified bearing design, corrosion resistance, high temperature resistance, noise reduction and vibration damping, etc. It is especially suitable for hot air ducts and soot pipes.
Second, the role of pipeline compensator:
1. Compensate for the axial, lateral and angular thermal deformation of the absorption pipe.
2. Absorb the amount of deformation of the pipeline caused by earthquakes and subsidence.
3. The amount of expansion and contraction of the corrugated compensator facilitates the installation and disassembly of the valve pipe.
4. Absorb equipment vibration to reduce the impact of equipment vibration on the pipeline.
Third, the main form of pipeline compensator
Pipeline compensator types are: three types: axial type, horizontal type, and angular type, and there are tens of thousands of models. More commonly used are: single axial type; external pressure axial type; direct buried type; one-time direct buried type; single, double hinge type; single and double universal type; double free type; straight, curved pipe pressure balance type ; rectangular corrugated compensator, and non-metallic compensator.
The compensator mode has natural compensation and compensator compensation:
Natural compensation is the use of the elasticity of the natural bending of the pipe itself to absorb the thermal deformation of the pipe. Pipe elasticity refers to the ability of the pipe to produce elastic deformation under stress, the geometry changes, and the stress disappears, and the original shape can be restored. Practice has proved that when the bend angle is greater than 30°, it can be used as natural compensation. When the bend angle of the pipe is less than 30°, it cannot be used as natural compensation. The length of the naturally compensated pipe is generally 15 to 25 m, and the bending stress σbw should not exceed 80 MPa.
Natural compensation cannot be satisfied, and a compensator should be added to the pipeline to compensate for the thermal deformation of the pipeline. The compensator is a component that is placed on the pipe to absorb the thermal expansion and contraction of the pipe and other displacements. Commonly used compensators include square compensators, bellows compensators, sleeve compensators, and spherical compensators.
Since the heat pipe made of metal such as steel has a relatively large change in length during thermal expansion and contraction, when designing and installing the heat pipe, it should be ensured that the pipe can be freely expanded and contracted, otherwise the pipe will generate huge heat. The stress causes the pipe to rupture and the flange joint surface is not tight, resulting in leakage and damage to the hanger and hanger. For this reason, the pipe should be thermally compensated.