A diaphragm seal is a device where a flexible membrane seals and isolates the measuring instrument from the process medium. The instrument side of the diaphragm is filled with appropriate fluid. The pressure exerted by the process fluid on the diaphragm is hydraucially transmitted through the seal fluid to the pressure sensing element. The seal protects the pressure sensor from the harmful and hazardous effect of the process fluid.
Types of seals
- Sandwich type – threaded and flanged
- Flush type – flanged only
- Pan cake type – flanged only
- In-line type – weld in and flanged
- Jacketed in-line – weld in and flanged
- Extended type – flanged only