What are the three main types of dead weight testers?

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 allows for more stable pressure readings.

3. Water Dead Weight Tester

• Description: Water is used as the pressure medium in this type of tester.
• Usage: Water dead weight testers are often used in environments where oil or gas contamination is a concern and for calibrating devices in the medium pressure range.
• Key Features: They are commonly used in industries where the use of oil is not acceptable, such as in clean room environments or when calibrating water pressure systems.

Each type of dead weight tester is chosen based on the specific application, pressure range, and the cleanliness requirements of the environment in which it will be used.