Blog posts tagged with 'mounting a pressure gauge'

For differential pressure applications with caustic or thick medias, mounting a differential pressure gauge directly to the process can be detrimental to the integrity of the gauge.  The wetted material of the gauge may corrode away or the differential gauge could potentially become clogged.

A solution to this problem would be to isolate the wetted parts of a differential gauge by mounting diaphragm seals made of a compatible metal or plastic to the inlet and outlet sides of the differential gauge.  However, unlike a standard pressure gauge with one port, you cannot mount a diaphragm seal directly to the differential gauge because the ports of the gauge are typically too close together to accommodate the size of the diaphragm seal.

A solution to this is to install capillary tubing in between the gauge and the diaphragm seal.  This allows for flexibility during installation, safety from high temperatures or vibration, and room for the diaphragm seals to fit on the gauge.  The entire assembly is a filled system just like a standard gauge mounted on a diaphragm seal.  The air is evacuated from the assembly and replaced with a fluid (usually silicone or glycerin).
For more information on differential gauges and/or mounting instruments to diaphragm seals, contact us.

A pressure instrument by itself typically has a small orifice for the media to enter into it for measurement.  This works perfectly fine for applications such as water, air, or oil measurements.  But what do you do if the media has solids in it, is thick, and/or solidifies when it cools that can potentially clog the pressure instrument rendering it useless?
The answer is mount a diaphragm seal to the instruments.  A diaphragm seal is specifically designed to be a barrier between the media and the pressure instrument.  Pressure gauges, pressure transducers, and pressure switches can all be mounted to diaphragm seals (or gauge isolators as they’re sometimes called) through a “filling process” creating a sealed system between the instrument and the seal allowing for the utmost accuracy.
There are many kinds of diaphragm seals and all are used based on what fits best for the application.  Some types include:

• Mini Diaphragm Seals
• Large Diaphragm Seals
• Plastic Diaphragm Seals
• Flow-Through Diaphragm Seals

IMPORTANT: You cannot simply screw on a diaphragm seal to a pressure instrument.  As mentioned above, it needs to be a filled system.  Essentially the instrument is mounted to the diaphragm seal.  Then air is evacuated from inside the connection and replaced with a fill fluid such as glycerin, mineral oil, or silicone.  This allows for an accurate reading.
For more information on diaphragm seals or the mounting process, please contact us.