Air pressure gauges are the most calibrated instruments in the process industries, as they are ones that tend to have their accuracy level change due to mechanical stress, environmental factors and more. Regular calibration of air pressure gauges is important to ensure that the process quality control is maintained. Calibrating air pressure gauges is best left to professional calibration experts, as it is an essential process that needs utmost care and diligence. Here are the important points to factor in when calibrating air pressure gauges.
- Classes of Accuracy: Before calibrating the air pressure gauges, it is vital to know the specified class of accuracy. In most instruments, the accuracy class is specified as ‘% of a range’. What this means is, if the instrument’s class of accuracy is 1 per cent and the scale range is mostly 0 to 100psi, then the accuracy is +/- 1 psi. The calibration experts need to know the accuracy levels of the instrument beforehand, so to calibrate it within the acceptable limits.
- Pressure Medium Used: while calibrating air pressure gauges, the pressure medium used in the calibrating instruments is air – normal air. If the pressure gauge was liquid-based, then the calibrating instrument also needs to use a liquid medium, which is usually ether oil or water.
- Contamination: The pressure medium such as air, that is used in calibration tends to get contaminated, this should be checked to ensure calibration is achieved with optimum results. The most common contaminant during air pressure gauge calibration is dirt, which could be present within the gauge. The dirt could hamper the calibration process, and even damage the calibration instrument.
- Leak Testing: It is important to check the piping system for any possible leaks, before calibrating the air pressure gauges. Leaks in the system will lead to calibration errors. One way to ensure there are no leaks is to pressurise the system and then let it stabilise for a while. The system is monitored for pressure drops, and too much of a pressure drop translates to a leak in the system. The leak has to be fixed before beginning the calibration process.
- Adiabatic Effect: Within a closed system the effects of the adiabatic process could be present, this needs to be noted while calibrating air pressure gauges to factor in any pressure drops due to the adiabatic effect. When there is a temperature rise it reflects on the volume of the gas and the pressure. When the temperature decreases, the volume decreases, leading to a pressure drop. This pressure drop may be considered as a leak in the system which will lead to errors in calibration.
- Torque Force: When working with torque-sensitive pressure gauges, it is vital to make sure that excessive force shouldn’t be used. The force used to connect the gauge to the pressure connectors should be within the specified limits or they may get harmed. Appropriate tools like adapters and seals should be used while calibrating such sensitive instruments.
At Zenith, we provide high-precision calibration solutions to ensure an accurate reading. As your one-stop platform for air pressure gauges, you can count on our service for all your needs. With over 27 years of combined experience, our professional calibration experts understand the crucial points to note and to check while calibrating air pressure gauges.
We understand pressure gauges and stock only the best quality, most economical models available, each specially designed for industries throughout Australia. We are authorised suppliers and distributors of, Dwyer, Micro and Zenith Pressure Instruments. Connect with us today to get accurate calibration services that comply with many international standard requirements.