Dual range pistons for pressure calibration

Dual piston deadweight testers can greatly enhance a lab?s ability to calibrate wide pressure ranges with the best accuracy. With transducers and devices under test (DUTs) that have a broad measuring range, calibration can be quite a lengthy process, as you must change pistons in between test points so that you can calibrate its entire range.
However, a dual piston deadweight tester is equipped with a high range piston and low range piston, that allows the technician more flexibility and efficiency in terms of calibration. pressure gauge 10 bar originates from decades of innovation and customer interaction to find a solution for industry needs.
Formula for pressure calculations
Because the Industrial Revolution, high accuracy pressure measurement has been a key requirement in process industries. Pressure measuring instruments like gauges were employed to measure and monitor pressure conditons. They must be calibrated against instruments of an increased amount of accuracy. Deadweight testers (generally known as pressure balances) are high accuracy instruments found in the calibration of electronic or mechanical pressure instruments. The core element of a deadweight tester is a precisely manufactured piston-cylinder system, onto which a mass load is applied so that you can generate the individual test points in a calibration.
The mass load is proportional to the mark pressure, which is achieved through optimally graduated masses. The look of the complete calibration system, in addition to the precise manufacturing of the piston and cylinder, ensure quality performance with long free-rotation time and low sink rates of the piston. With pressure gauge octa down to 0.002% of reading, deadweight testers will be the golden standard in calibration.
A deadweight tester typically consists of a single piston-cylinder system. This requires mass sets to be changed so as to calibrate multiple or wide measuring ranges. This may become a cumbersome process, one which requires many resources. In 1953, the entity today known as DH-Budenberg pioneered the first dual range piston-cylinder technology with two pistons housed concentrically in one unit. DH-Budenberg was later acquired by WIKA in 2011. The initial design included 1/8 in2 (low pressure) and 1/180 in2 (ruthless) pistons housed in a single unit. Using a single mass-set it had been now possible to generate two points of equilibrium at 55 bar (low pressure) and 550 bar (ruthless) respectively. This is followed with the release of high pressure variant which could generate pressure upto 1100 bar.
Explanation dual piston design
The first dual piston design was largely constructed of tool roll, and had an accuracy of 0.03 % of the pressure being measured in the typical model and 0.05 % in the high pressure model. In dual piston calibration, the load on the reduced pressure piston is transferred to the auxiliary piston, that is directly linked to the weight carrier. When correct pressure is obtained, the piston head skirt floats within the low range or ?blue band.? To attain high pressure, the pressure is increased and the reduced pressure piston rises until a knife-edge on underneath flange makes a seal contrary to the low pressure cylinder and acts as the high pressure cylinder. Since the low pressure piston does not contribute to the entire weight of the piston and weight carrier, the weight carrier accumulates the auxiliary weight to pay. When correct pressure is achieved, the piston head skirt floats within the high range or ?red band.?
This iconic, patented DH-Budenberg red and blue band piston-cylinder system was re-engineered later with both piston and cylinder components made of tungsten carbide. With the refinements in pressure generation and piston manufacturing processes, dual ranges are now available around 1,400 bar with accuracies right down to 0.006 % of reading.
These developments in dual piston technology made deadweight testers, such as for example DH-Budenberg? ไดอะแฟรม ซีล , the premier deadweight tester for industrial applications. It is especially ideal for calibrating a transducer with a wide measuring range, while maintaining the high accuracy for testing and calibration. With the use of just a single mass set and calibrating instrument, this system can automatically switch between multiple test points of high and low pressure, making pressure calibration seamless, efficient and economical.
Further information on our pressure balances can be found on the WIKA website.

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