What is a Dead Weight Tester & How it works?

Every business that uses pressure instruments to monitor fluid and gas pressures and flow rates relies on accurately calibrating today's high-tech pressure measurement instruments. Pressure is a complex measurement discipline. And to have precise measurements, pressure gauge calibration is necessary. That's where pressure calibrators come in.

There needs to be a calibration kit for pressure gauges that is universally suitable for all users' needs. Pressure gauge calibration standards diverge substantially based on their uses and the setting in which they are utilized.

That’s why there are different types of pressure calibrators for different scenarios. For example, a dead weight tester, multifunction calibrator, or measuring gauge with a predefined accuracy can examine the accuracy of transmitters, sensors, transducers & pressure gauges.

Today, we will review what these dead-weight testers are and how they work.

Deadweight Testers - What are They?

The DWT - Dead Weight Tester is a pressure-monitoring system that helps maintain pressure by dividing the force's weight by its applied area. DWT offers excellent calibration accuracy for pressure gauges and guards against inaccurate pressure readings. 

Deadweight testers provide a quick and inexpensive approach to assess a range of pressure calibrations by utilizing calibrated weights to drive desired pressure ranges to a system under test. Adding a deadweight tester is important because the instrument may house all the technology necessary to create pressure, measure it & regulate it more precisely.

Pressure gauges, sensors, transmitters & transducers are just a few examples of the many pressure measurement devices that leverage it for calibration. Dead Weight Testers have become the major standard for measuring pressure with stability, precision, and repeatability.

But where are they used? Let’s take a look.

Deadweight Testers - The Many Uses

A dead weight tester is sometimes referred to as a primary reference standard because it is thought to yield the most accurate findings due to the great degree of accuracy with which the weight mass & the radius of the piston cylinder are well-known.

When used incorrectly, a few factors can significantly affect the measurement uncertainty of a deadweight tester. It includes mistaken local gravity correction, loss of mass from scratches on the weights, loss of friction from improper upkeep of the piston cylinder assembly, measures taken without spinning the weights, and failure to guarantee that the base is horizontal.

Today, standards laboratories mainly utilize dead-weight testers to offer a reference standard for pressure calibration needs.

So, How Does it Work?

A DWT (Dead Weight Tester) is a pressure calibration tool that sets pressure setpoints precisely across a broad range of pneumatic or hydraulic pressures using metal baggage & piston parts.

Since pressure is computed by dividing the applied force by the surface area of the piston cylinder (P= F/A), the pressure produced by a deadweight tester is estimated by doubling the overall mass by the gravitational acceleration. 

A screwpress provides pressure, while a gas monitor is used for pneumatic methods. The allocated pressure is obtained when the weights are lifted to a floating position using the screwpress or regulator.

To be precise, the letters P, F, and A stand for the reference pressure in pascals (Pa), the force acting on the piston in Newtons (N), and the effective area in square meters (m2).

Most applications requiring calibration fall within the 0–2500 bar pressure range. On the other hand, Deadweight testers can measure pressures up to 10,000 bar. This calibrating device has a high accuracy range of 0.005% to 0.1%.

Modern dead weight tests can offer cutting-edge physical compensation and are highly accurate and sophisticated. They can create an intelligent calibrator device that can register all important environmental variables, improve reading accuracy, and automatically adjust readings precisely.

The Bottom Line

Accurately adjusting and quantifying an instrument's pressure is the main advantage of using a Dead Weight Tester. The Dead Weight Tester also offers the most precise and affordable option for calibrating additional pressure systems/measuring unknown pressure when high precision is needed.

At Nagman, we have the best dead-weight testers of the highest caliber. Our top-notch calibrators are simple and efficient when fine-tuning or making adjustments. Are you looking for top-notch calibrators? Feel free to browse our products to find the best fit for your needs!