A pressure gauge without a pointer

a magnehelic pressure gauge without a pointer

When we audited a baghouse dust collection system, we saw this abandoned Magnehelic pressure gauge without a pointer in situ for the purpose of decoration only.

Actually, it is very normal to see a malfunctional gauge on-site, for reasons such as mechanical vibration, pressure pulsation, elevated temperature, pressure differential out-of-range, connecting-hose clogging, mishandling and abuse, etc.

For a pressure gauge to lose its pointer is not uncommon either. Mechanical vibration is the major reason the connection of the pointer loosens and consequently drops to the bottom of the gauge housing.

The gauge in the above picture was installed on the support frame of the baghouse together with a differential pressure transmitter. We guess abnormal vibration caused by the baghouse operation on the whole support frame failed the gauge, or maybe the connection of the pointer was loose even before it was installed on-site.

Magnehelic Differential Pressure gauges are an integral part of a dust collecting system. By constantly measuring the differential pressure, these instruments offer an easy visual indicator of whether the system is operating within the desired differential pressure range or if a problem is imminent.

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