Methods to calibrate a Pressure instrument

There are two methods to calibrate a pressure instrument.

a) Dead weight Calibration,

b) Reference calibration.

In dead weight Calibration Instruments are calibrated against calibrated weights. In reference calibration the instruments are calibrated against a calibrated Master Instrument. Though as a primary standards, Dead Weight Testers are the most accurate Instruments for the calibration of electronic or mechanical Pressure Instruments, it require up loading and down loading of weights for every single increment and decrement, which require more time to calibrate an instrument. In reference calibration changing of a Master instrument is required only when the range of the test instrument is changing, thus it provides faster Productivity without compromising on quality. Regarding the calibration of master / Dead weights, one has to do the periodical calibration for both - irrespective of whichever one is using.

What is a Pressure gauge and how it is constructed?

A Pressure gauge is a mechanical instrument- instrumented for measuring process Pressure. And it is constructed with a pressure sensing element, inlet connection, a display dial and indicating pointer. And then these systems are protected with a cover and clear window.

Understand the process - reduce instrument failure.

There are several reasons to the failure of an instrument. Before selecting a product one has understand the process thoroughly. Do not install or replace an instrument only because it is used at a particular location or decided by hierarchy. While selecting a product, if one is not aware of the instrument, go through the following steps:
• Select the specification like operating pressure, Temperature and media under use.
• Check with your vendor to match you requirement
• Standardize on nearest specification to vendor’s scope
• Make sure that the selected range is to be loaded by 30 to 40% so that the instrument may in safer working mode.