Classification of bellows compensator: disposable bellows compensator U-shaped metal expansion joint bellows compensator three-dimensional coal special bellows compensator hinge bellows compensator (JJL type) balanced curved pipe pressure bellows compensator ball type QB stainless steel bellows compensator, etc. Corrugated compensator is also called expansion joint, or expansion joint. It is composed of bellows (an elastic element), end pipe, bracket, flange, conduit and other accessories that constitute its main body. It belongs to a compensation element. Use the effective expansion deformation of the bellows of its main body to absorb the size changes of pipelines, conduits, containers, etc. caused by thermal expansion and contraction, or compensate for the axial, lateral and angular displacement of pipelines, conduits, containers, etc. It can also be used for noise reduction and vibration reduction. It is widely used in modern industry.

1、 Standard of corrugated compensator:
Standard No. of corrugated compensator: GB/T 12777-1999
Standard name of corrugated compensator: general specification for metal bellows expansion joints
Standard implementation date: March 1, 2000
Issued by: National Bureau of Quality and Technical Supervision
Content introduction: This standard specifies the definition, classification, requirements, test methods, inspection rules, marking, packaging, transportation, storage, etc. of metal corrugated compensators. This standard is applicable to the design, manufacture and inspection of the circular bellows compensator installed in the pipeline with its flexible parts being integrally formed unreinforced U-shaped, reinforced U-shaped and U-shaped bellows. The design, manufacture and inspection of expansion joints for pressure vessels can also be referred to.

2、 Connection mode of corrugated compensator:
The connection mode of corrugated compensator is divided into flange connection and welding. The directly buried pipeline compensator is generally welded (except for trench installation)
Selection of compensator
Bellows compensator is a disturbing element with bellows as its core. It can compensate in three directions: axial, horizontal and angular on the pipeline. In order to reduce the self-excitation of the medium, the axial image compensator is equipped with an inner sleeve inside the product, which greatly limits the radial compensation ability, so it is generally only used to absorb or compensate the axial displacement of the pipeline (if a small amount of radial displacement is really needed in the pipeline system, it can also absorb the combination of axial, angular and any three directions of displacement; hinge compensator (also known as angular compensator), It is used with two or three compensators (a single hinge compensator has no compensation capacity) to absorb the lateral deformation in a single plane; Universal joint (angular) compensator, which is used by two or three matching devices, can absorb the deformation in three-dimensional direction.

Correct and reasonable use of bellows compensator:
1. Corrugated pipe compensator is generally installed on hot water, steam, smoke and air, gas and other thermal pipelines to absorb the deformation caused by heating.
2. The outlet of the pump is suitable for installing metal flexible connection (also known as metal hose). Because it is difficult to set the fixed support for the pump room pipeline, the compensator is easy to be damaged by pipeline stretching at the pump outlet.
3. When selecting the compensator, the manufacturer shall be provided with the corresponding coefficients of pipe diameter, medium temperature, pressure, compensation amount, etc. The manufacturer shall calculate the best design data to ensure the best service life of the compensator.