The pressure test standard for metal hoses is an important test procedure to ensure that they can operate safely under the design pressure. The pressure test is mainly to verify the structural strength and sealing performance of the hose. The following are the general standards and procedures for pressure testing of metal hoses:
Pressure test media：
The pressure test usually uses pure water as the medium, and the chloride ion content should not exceed 25ppm to avoid potential corrosion of the metal hose.
Test pressure：
The test pressure is usually 1.5 times the rated working pressure of the hose, and this value may vary depending on the standard and the type of hose.
For some special applications, the pressure test pressure may be higher, such as reaching 2.0 times the rated pressure or higher.
Pressure test equipment：
Pressurization is performed using a manual or electric pressure test pump.
Pressure testing instruments, such as pressure gauges, should have a range of 1.5 to 4 times the test pressure or use equivalent pressure testing instruments.
Pressure test process：
Place the hose test piece straight.
A plug with an exhaust valve is installed at one end, and the other end is connected with the outlet pipe of the pressure test pump.
Inject pressure test medium and exhaust air.
Close the exhaust valve and slowly increase the pressure to the specified test pressure value.
Keep the pressure steady, typically for 5 minutes, to check for leaks, cracks, or other abnormalities.
After the test, slowly release the pressure to prevent damage caused by a sudden drop in pressure.
Acceptance criteria：
Qualified metal hoses are not allowed to have any leakage or damage during pressure testing.
Pressure test under special conditions：
For some applications, such as mine metal hoses, low voltage detection has a pressure of 1MPa and a duration of 5 minutes.
High pressure testing may involve higher pressure, and the specific requirements are according to national standards.
Alternative pressure test：
In some cases, pressure testing using air pressure instead of water pressure is allowed if the safeguards are sufficient to ensure personal safety, but this is generally not recommended because of the higher risk associated with air pressure testing.
International and national standards：
The pressure test of metal hoses shall follow applicable international standards, such as ISO standards, or national specific standards, such as China standards (GB/T), American Society of Mechanical Engineers standards (ASME), European standards (EN), etc.
When performing the pressure test of metal hoses, it shall be carried out in strict accordance with the manufacturer's guidance and relevant safety regulations to ensure the safety of all participants and ensure the validity and accuracy of the pressure test results. If metal hoses are to be used in critical applications, detailed inspections are recommended both before and after pressure testing to ensure hose integrity and performance.