QUALITY CONTROL PROCESS
1. 100% Inspection on Steel Tube
Visual inspection includes: inner & outer surface cracks, indentations, wrinkles, scars, scratches.
Dimension inspection refers to: tube thickness, outter diameter, ellipticity and straightness, etc.
2. 100% Crack Inspection on the bottom
a. Bottom visual test covers the tests of outer surface scar, wrinkle, indentation, projection, etc.
b. Bottom blending test consists of ultrasonic thickness measurement and Ultrasonic Flaw Detection.
3. Ultrasonic Flaw Detection
Ultrasonic thickness measurement and Ultrasonic Flaw Detection have been 100% done on cylinder body after heat treatment, to prevent any possible hazard for the cylinder.
4. Magnetic Powder Inspection
We do full magnetic powder inspection on the cylinder surface thoroughly to detect defective cylinders with wrinkles or cracks.
5. Hydraulic Pressure Test
Hydraulic test is strictly done to make sure the cylinder deformation ratio complies with relevant standards so as to avoid any possible hazard.
6. Leakage test for finished cylinder
Leakage test is 100% done to ensure no leakage from the cylinder or valve under nominal pressure.
7. Finished product inspection
We do strict final inspection on the finished products, including painting apperance, valve installation, punch marking and packing quality, in order to make sure no any defective cylinder will appear as a final product, thus to guarantee each cylinder manufactured by us will be a perfect one.
8. Mechanical properties testing
After heat treatment, we do metal mechanical properties test on each batch to make sure our cylinders 100% comply with relevant standards.
9. Metallurgical structure testing
We test the metallurgical structure and decarburization on each batch of cylinders after the heat treatment, in order to make sure our cylinders are 100% qualified and comply with the related standards.
10. Chemical analysis testing
For each batch of steel tubes, we perform spectrum analysis on the chemical elements, to verify the chemical elements of the steel tube meet relevant standards.
11. Cyclic fatigue lifetime test
We perform cyclic fatigue lifetime test on each batch of cylinders under normal temperature to guarantee our cylinders conform to relevant standards.
12. Hydraulic bursting test
We do bursting test on each batch to make sure the bursting pressure, bursting shape and position comply with the related standards, so as to avoid any possible hazard.