A manufacturer needs to test the bellows for strength and leaks before installing an expansion joint or metal bellows into a piping system. Hydrostatic testing is one technique experts use. Essentially, it uses water to see if the expansion joint can withstand the pressure or vibrations it’ll need to endure to operate properly.
There are three different methods of hydrostatic testing that joints could undergo. Learn more about how we test our expansion joints to verify our designs and engineering match your specifications.
What Is Hydrostatic Testing?
Hydrostatic testing is a technique manufacturers use to test expansion joints for leaks and weaknesses. Sometimes, cracks or other imperfections have the possibility of forming during manufacturing.
Experts fill the bellows or joint with a non-reactive liquid—usually water. They then apply pressure slowly and evenly until they reach the pressure the bellows will need to withstand while operating.
Methods of Hydrostatic Testing
Even though every hydrostatic test uses a liquid, there are different ways to perform the tests. Here are the three methods you should know.
Water Jacket Method
In the water jacket method, workers use a sealed chamber, called the water jacket, to measure the amount of water displaced when workers apply internal pressure to the joint. The bellows expands, forcing the water out of the water jacket and into a vessel. This vessel measures how much it expanded.
Direct Expansion Method
Like the water jacket method, experts fill the bellows with water to pressurize the joint. Then, they measure the amount of water pushed out to determine how much pressure it can withstand. They find these values by recording three factors: the amount of water forced out of the vessel, the amount of water forced into the bellows, and the pressure used.
Proof Pressure Method
The proof pressure method is the simplest of the different methods of hydrostatic testing. Experts apply internal pressure to see if the bellows has leaks or any weakness. But they don’t record any measurements.
Expansion Joint Installation
Before any expansion joint installation, we test our equipment with hydrostatic testing or another testing technique to ensure it meets your design and engineering requirements. Contact us at Triad Bellows to learn more about our expansion joint testing methods.
