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Diaphragm Seal Fit and Fill Service

A diaphragm seal’s main purpose is to protect the pressure instrument from the process medium. Diaphragm seals are normally connected directly to the instrument but connection may be made by a capillary. The air space behind the diaphragm membrane and inside the instrument is filled with a fill fluid which acts as a hydraulic medium. When pressure is applied to the diaphragm membrane it is hydraulically transmitted to the instrument’s sensing element by the displaced fill fluid. This allows the instrument to measure the process pressure without making direct contact with the process.
We produce a comprehensive range of diaphragm seals to suit hygienic and chemical applications
Careful consideration of the operating pressure, operating temperature and the ambient temperature is required when selecting a suitable fill fluid. Fill fluids must be chemically compatible with the process fluid to avoid a hazardous reaction or contamination problems in case of a diaphragm failure. For example the Food and Pharmaceutical industry require that FDA (Food and Drug Administration) approved fill fluids must be used. Chlorine and Oxygen media applications require inert fill fluids such as Halocarbon to prevent a violent reaction that may cause fires. Our selection of fill fluids allows us to cover a variety of pressure and temperature applications from -73ºC to +370ºC.
Most fill fluids contain microscopic amounts of air and trapped gases which expand with rising temperatures. This expansion within the fill fluid can cause the instrument to indicate a false pressure readingTo prevent this, these gases must be extracted (degassed). PCI use a bespoke turbo molecular vacuum filling station. The filling station can pull a powerful vacuum as low as 10x-9 (0.000000001) mbar absolute. This high level of vacuum is capable of extracting gases and moisture from even tiny pores in stainless steel. The filling station degasses the fill fluid and creates a vacuum in the air space inside the instrument for the fill fluid to occupy. The fill fluid is drawn in to this space by the vacuum and then sealed in. After testing to ensure its accuracy the diaphragm seal system is complete.
We provide a fit and fill service with our diaphragm seals. Many leading pressure transmitter companies free issue their instruments to have a PCI diaphragm seal fitted. Our charge for this service is competitive and we offer a fast turn around time. This is often crucial for the end client. We have fitted our seals to brands such as Endress + Hauser, Honeywell, Foxboro, Yokogawa, Rosemount, Siemens, ABB, VEGA, IFM, Ashcroft, WIKA and more.
Specialised secure packaging we developed is used to ensure our diaphragm seal systems can arrive safely to any where in the world. 
Diagnostics and Upgrade Service
If you are experiencing problems with your diaphragm seal system you may wish to send it to us. We can carry out a full diagnostics service and establish the cause of the problems. We can then upgrade your existing diaphragm seal system to improve its performance and operational life.