THE USE OF DEADWEIGHT TECHNIQUES
This experiment was about to investigate the use of deadweight techniques to calibrate pressure gauges. In which measuring a pressure practically with the help of an instrument. This instrument is known as a deadweight tester. The deadweight tester used to calibrate the pressure with the help of a bourdon tube pressure gauge. But the difference is that using deadweight tester pressure is a comparison between actual and theoretical pressure. It works on the principle of Pascal’s law which states that a change in pressure at one part of a closed container. It is very important or necessary to transmit to the walls of a closed container. To perform calibration with a deadweight tester, carry fasten a pressure measurement device to the tester and equate the known pressures to pressure readings from the device under test.
The experiment was about to show the working of the deadweight tester and bourdon gauge. Multiple devices used to measure pressure but the deadweight tester is useful because it gives accurate values. A dead weight tester is an instrument or device in which pressure is calibrated by setting the weight of force divided by the area the force is applied. Instrument calibration one of the direct procedures used to maintain instrument accuracy.
The deadweight tester consists of different apparatus like a deadweight calibrator, set of test weights, weight balance, and bourdon pressure gauge. It’s the procedure of configuring a device to give results within a respectable range. Given Weight applied on a deadweight calibrator to apply pressure to a fluid.
Deadweight generally utilized to acclimate pressure as they come with high delicacy. Therefore, can be used as the primary standard.
Proceed with calibration according to the following way.
- Link the pressure gauge to the experimentation on the deadweight tester. The test gauge readings are zero, if zero error is left also remove this error.
- Chose a load and place it on the vertical piston.
- Rotate the handgrip of the acclimating piston or screw pump to ensure that the load and piston are sported freely by oil.
- Rotate the vertical piston and ensure that it is hanging freely.
- Give some time for the system to stabilize before taking any readings. After the system has stabilized, Record the gauge reading and the load.
Results and Discussion:
The calculation that was obtained is given below.
|Sr.NO.||Applied Load (Kg)||Applied Load (N)||Area (m2)||Theoretical Pressure (N/m2)||Practical Pressure (N/m2)||Percentage Error|
We observed that experimental or practical readings are different from theoretical values. Two distinct types of blunders may normally expect in a gauge of this kind. Firstly, there’s a chance of hysteresis, friction, and counter-reaction which may yield lower gauge readings when the pressure is adding, also when it’s decreasing. Secondly, there is a blunder due to the scale being marked off wrongly.