Boiler tubes is an important material for manufacturing boilers, it will be directly related to the the boiler manufacture of quality so that the quality of the installation and use of quality. Quality of boiler tube should be made of steel plant to guarantee, but in the case of short supply, supplied to the boiler pipe used by the boiler manufacturer always found some quality problems, mainly use it made of boiler pressure parts such as waterwall tube, convection tubes, superheater tubes, heat exchanger tubes leaking or burst pipes phenomena have occurred, has become a big problem that plagued the boiler quality, this boiler manufacturers and users are opinions. In the case of a seller’s market, the boiler manufacturer almost assume full responsibility for the material supply side, including; how to control the quality of the boiler tube boiler manufacturers are increasingly concerned about the problem has now become the most weight on the boiler tube hydrostatic testing.
China’s national standard GB3087-82 low pressure boiler seamless steel pipe: steel pipe for hydrostatic testing should be out by the root, process performance requirements in the technical requirements, not leaking or sweating phenomenon. 20 steel maximum test pressure 9.8MPa, withstand voltage shall not be less than 5 seconds. Hydrostatic test pressure is calculated as follows: P = 2 * S * T / D
The formula: P – test pressure, in MPa; s – the wall thickness of the steel pipe, mm; D – the outer diameter of the steel pipe, mm; T – Steel No. predetermined yield point of 60%, MPa
It is generally believed that the purpose of hydrostatic testing two types: one is the hydrostatic testing of the craft, its purpose is to test materials (or components) for leaks, the sealing performance of the test material; another confirmatory hydrostatic test The aim is to test the strength of the material (or member) whether sufficient. From here we can see, the hydrostatic test of the boiler tube is the process of hydrostatic test, material density test, the test material is continuous and whether dense; it is not to verify the strength test. Seen from the strength of the material mechanics theory, seamless steel tubes are thin and long component, its small diameter, thin tube wall thickness thinner under a lot of pressure.
Post time: Aug-30-2019