3. When selecting the filter pressure reducing valve, pay attention to the pressure range, flow medium, working temperature, drainage device (self draining, manual draining) and filter element precision of the filter pressure reducing valve.
4. When selecting limit switches, pay attention to whether the feedback mode (mechanical and inductive), the color of position indication and the corresponding explosion-proof grade meet the requirements.

Principle and design requirements of bellows rotary compensator
The main elastic element of the corrugated compensator is the stainless steel bellows, which is used to stop the axial, transverse and angular compensation of the pipeline relying on the expansion and bending of the bellows. Its function can:
1. Compensate the axial, transverse and angular thermal deformation of absorption pipe.
2. Absorb equipment vibration and reduce the impact of equipment vibration on pipeline.
3. Absorb the deformation of pipeline caused by earthquake and ground subsidence.