Dead weight testers are precision instruments used to calibrate pressure measurement devices by applying a known weight to a piston of a known area. The three main types of dead weight testers are: 1. Gas Dead Weight Tester Description : This type uses a gas, typically air or nitrogen, as the pressure medium. Usage : Gas dead weight testers are commonly used for calibrating low-pressure devices, particularly in industries where oil contamination is undesirable (e.g., aerospace, pharmaceuticals). Key Features : They provide a clean pressure source and are ideal for low-pressure applications, typically below 20 bar. 2. Oil Dead Weight Tester Description : This type uses a hydraulic fluid, usually oil, as the pressure medium. Usage : Oil dead weight testers are used for calibrating devices at medium to high-pressure ranges, typically from 10 bar to 1,000 bar or more. Key Features : They are preferred for high-pressure applications due to the incompressibility of oil, which a...