Dead Weight Testers

Dead Weight Testers for Traceable Pressure Calibration

A dead weight tester defines pressure rather than measuring it: a calibrated mass set loads a piston of known effective area, and the resulting pressure follows directly from mass, gravity and area. Nothing in that chain depends on an elastic sensing element, which is why these instruments hold their accuracy over decades and sit at the top of a calibration programme.

The range covers hydraulic and pneumatic versions, with manual weight stacking or automatic loading. Hydraulic units reach the highest pressures and use oil or deionised water as the pressure medium; pneumatic units keep the setup clean where the device under test must not see oil. Automatic loading removes the operator-dependent part of the measurement, which is where most of the repeatability of a manual dead weight tester is otherwise lost.