What is Hydrostatic Testing?
Hydrostatic testing is a pressure test performed to check the extinguishers cylinder and other critical components for cracks, leaks, and other structural flaws that may cause the extinguisher to malfunction when you need it.
At Approved Protection Systems we utilize the Water Jacket type test to determine the condition of the extinguisher. First, the extinguisher valve is removed and the threads and interior of the cylinder are checked for corrosion, pitting, and any other abnormalities. If the cylinder passes the visual inspection, it is placed into a steel chamber, which is then filled with water at normal pressure. A glass burette connected to the steel chamber will read zero, indicating normal or zero pressure of the chamber water. Water is then applied at high pressure to the interior of the extinguisher’s cylinder. As the pressure increases, the cylinder will expand and push water from the steel chamber through a small hole and into the glass burette. After the pressure is released, the cylinder will contract and the water will move from the burette back to the steel chamber. Depending on the results, the tester will either pass or fail the cylinder.
See how often you need to get your extinguisher hydrostatic tested.
Extinguisher Maintenance Schedule Guide
Visual Eddy Current Testing
In addition to Hydrostatic testing, all aluminum cylinders will go through an Eddy Current test. The Eddy Current test will diagnose small imperfections, such as hairline cracks and folds in the neck/shoulder area of aluminum cylinders. An electromagnetic wave is introduced into the metal of the vessels near the area which is desirable to inspect for imperfections (the threaded area). The wave causes currents to flow in a circular manner in the metal. They are called eddy currents because the flow is circular. An imperfection can increase the path that the currents have to flow and so make the material appear higher in resistance in that region where the imperfection is present. This generates a spike on the computer generated report which alerts the technician to a problem that requires further investigation.