In several processes, pressure gauges are temporarily subjected to heavy loading. Dynamic load cycles, for example, can permanently damage the measuring instrument. This can be prevented by mounting the appropriate Fittings.
Dynamic load cycles often result from pressure surges from a pump. They are visible on pressure gauges as pointer fluctuations. The result of such load cycles is not only in limiting the readability of the display: The elastic pressure element and all mechanical components are also highly stressed. The increased loading will eventually lead to a reduction in the service life of the pressure gauge.
The effects of load cycles can be clearly reduced through an additional fitting in the form of a snubber. In fact, a restrictor can be built in directly as a fixed constriction in the pressure port during the pressure gauge’s manufacture. However, the great advantage of an external restrictor fitting is in the variable adjustment of the volume flow of the media. Through the adjustable cross-sectional restriction using the adjustment screw, the load cycles can be optimally damped. Also, any change in the viscosity of the media can be “compensated for” using this mechanism.
Syphon
Depending on the process, pressure gauges can be subjected to other effects, in addition to load cycling – for example, high temperatures. In such cases, the combination with a syphon or compact syphon is worth considering. This protects particularly effectively when hot media, such as vapour, occur in conjunction with load cycles.
Note
Further information on fittings for pressure gauges can be found on the WIKA website under the heading Valves and protective devices.