The fire extinguisher hydrostatic test is essential before and after refilling fire extinguisher. It uses water as the test medium, and pressurizes a fire extinguisher to simulate its working environment, thereby determining whether the material strength and structural integrity of the fire extinguisher are qualified. There are many types of fire extinguishers, but ultimately they are divided into two main categories: seamless steel cylinders and welded steel cylinders, which require two different types of fire extinguisher hydrostatic test equipment respectively.
Water Jacket Method Fire Extinguisher Hydrostatic Test
For high-pressure fire extinguishers, such as Co2 extinguishers and IG extinguishers, which store high-pressure gas inside. Therefore, the body of high-pressure fire extinguisher is usually seamless steel cylinder. The high-pressure fire extinguisher requires a water jacket method hydrostatic test machine to perform fire extinguisher volumetric expansion test.
The water jacket method extinguisher hydro test involves placing the fire extinguisher in a sealed water jacket. And using water as the test medium to pressurize the extinguisher to 1.5 times its working pressure and then maintaining the pressure. During pressure holding period, the fire cylinder will expand due to internal pressure, thus squeezing some water in the water jacket to a measuring cup. After pressure relief, the fire cylinder will restore partially, so some water in the measuring cup will return to the water jacket. By measuring the amount of water remaining in the measuring cup, we can calculate the volumetric deformation rate of the fire extinguisher. Generally speaking, if a fire extinguisher’s expansion rate exceeds 10%, it is unqualified and cannot serve any longer.
Fire Extinguisher Hydraulic Burst Test
As for low-pressure fire extinguishers, such as NOVEC FM200 extinguishers and DCP dry powder fire extinguishers, which store low-pressure extinguishing agent inside. Therefore, the body of low-pressure extinguisher is welded steel cylinder, thereby only requiring hydraulic burst test. which’s operation is much simpler. You only need to connect your fire extinguisher to the hydro test machine, then use the machine to pressurize the extinguisher to 1.5 times its working pressure and maintain the pressure. During pressure holding period, if the fire extinguisher body does not crack and its internal pressure drop is within the design allowable range, it proves that the fire extinguisher is qualified. If you want to test the ultimate pressure that the fire extinguisher body can withstand, continue pressurizing the extinguisher body until it cracks. The pressure that causes the extinguisher body to crack is the fire extinguisher’s burst pressure.
Which Fire Extinguisher Test Method is Suitable for Me?
The fire extinguisher water jacket method hydrostatic test is only applicable to high-pressure fire extinguishers, such as Co2 fire extinguishers, IG55 IG541 Inergen fire extinguishers. While the fire extinguisher hydraulic test is suitable for low-pressure fire extinguishers, such as NOVEC FM200 clean agent extinguishers, DCP dry powder fire extinguishers and foam extinguisher.
Frequently Asked Questions
What is the fire extinguisher hydrostatic test interval?
Foam extinguisher hydrostatic test interval is 1 year, DCP and Co2 extinguisher hydrostatic test interval is 2 years, IG541 IG55 extinguisher hydrostatic test interval is 3 years, FM200 and NOVEC extinguisher hydrostatic test interval is 5 years. Of course, different countries may have different regulations.
What does the high-pressure fire extinguisher include?
Only Co2 extinguishers and IG55 IG541 extinguishers are high-pressure fire extinguishers, with seamless steel cylinders. All other types of fire extinguishers are low-pressure fire extinguishers.
