Sunday, April 21, 2013

The Pressure Gauge Working

The Pressure Gauge

The pressure gauge is a sensitive and delicate device which tells us the pressure. Usually use on pressure line, pump discharge. They are remotely display at appropriate place by using small brass line know as capillary.
Inside is a bourdon tube, linkage, gears and needle. This whole assembly is fitted in a closed glycerin glass (at front and MS sheet at back). The purpose of glycerin is to lubricate the whole assembly also it absorbs small jerks.
There is a filling cap at top of pressure gauge. It may have a hole or not. If you keep the hole closed in a leaking bourdon tube it may damage the glass and also become pressurized. So it is a safety not to close the top plug if it is leaking.
Yesterday night (23-10-2012)there was an alarm of Exhaust Valve Drive Pressure low in this case the pressure gauge switch the second stand by pump incase 1st one malfunction.
The alarm rises due to pressure drop by pressure leaking bourdon tube. It is rectify by closing the main cock then blanking the pressure gauge line so that actual flow (2.8 to 3.4 Bar) remain in the line.

Written By
Zeeshan Ahmed
46th Batch PMA
92 334 4011232

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