What is the difference between a transmission joint and a limit expansion joint?

The limit expansion joint is composed of the main body, sealing ring, gland, expansion short pipe, and other main components.

The transmission joint is composed of components such as flange loose sleeve expansion joint, short pipe flange, and transmission screw.

The model of the limit expansion joint is VSSJA-2, abbreviated as B2F; The model of the transmission joint is VSSJAF, abbreviated as C2F. What is the difference between a transmission joint and a limit joint?
The main function of the power transmission joint is to transmit axial thrust, connecting the valve and pipeline as a whole. Its installation length can be adjusted by bolts. Common power transmission joints include double flange power transmission joints, single flange power transmission joints, and detachable double flange power transmission joints.

In pipelines, the main function of expansion joints is to extend and compress, compensate for the displacement caused by thermal expansion and contraction of the pipeline, and facilitate the installation, disassembly, and maintenance of valves and pumps.

Appearance:

From the appearance, it can be clearly seen that there are four flanges on the limit expansion joint body, while there are only three flanges on the transmission joint body. The limited position bolts and short bolts of the expansion joint shall not exceed the product itself, and the force transmission bolts of the power transmission joint shall be longer than the product itself.

Function:

Expansion joints can expand and contract axially within a certain range and overcome the deviation caused by the pipeline’s axial direction within a certain angle. At the same time, they can freely expand and contract within the allowable expansion amount of the pipeline. However, once the expansion limit bolt is exceeded, it plays a limiting role to ensure the safe operation of the pipeline.

The transmission joint needs to adjust the required installation length of the pipeline according to the reserved distance of the pipeline before installation, connect the transmission bolts, and lock the length. Therefore, it only serves as a connection during pipeline operation.