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API 5CT oil casing pipe, hardness is a very important indicator. Only oil casing with qualified hardness can ensure the effect when used. On the contrary, if the hardness is unqualified, it is likely to cause problems during use. Accidents cause danger. If you want to know the hardness of API 5CT oil casing, you can actually test the oil casing through experiments.
1. Tensile test
Tensile test is to make API 5CT petroleum casing into a sample, pull the sample to fracture on a tensile testing machine, and then measure one or several mechanical properties. Usually only tensile strength, yield strength, and elongation after fracture are measured. and area reduction. Tensile test is the basic mechanical property test method for API 5CT petroleum casing. Almost all metal materials, as long as they have requirements for mechanical properties, require tensile testing, especially those materials whose shapes are not convenient for hardness testing. Testing has become the only method for testing mechanical properties.
2. Hardness test
The hardness test is to slowly press the hard indenter into the surface of the API 5CT petroleum casing sample using a hardness tester according to specified conditions, and then test the indentation depth or size to determine the material.
The size of the hardness. Hardness test is a simpler, faster and easier to implement method in material mechanical property testing. The hardness test is non-destructive. There is an approximate conversion relationship between the material hardness value and the tensile strength value. The material hardness value can be converted into a tensile strength value, which is of great practical significance.
Since tensile testing is inconvenient and it is convenient to convert hardness to strength, more and more people only test the hardness of materials and less often test their strength. Especially due to the continuous advancement and innovation of hardness tester manufacturing technology, it is now possible to directly test the hardness of some materials that could not be directly tested for hardness in the past, such as API 5CT petroleum casing. Therefore, there is a hardness test that gradually replaces the tensile test. trend.
The actual wall thickness of API 5CT oil casing is often clearly defined, and the deviation range is basically about 5%. API 5CT oil casing requires that the appearance must be painted with anti-corrosion paint. Manufacturers must pass API certification and issue API 5CT certificates. Production and oil fields can only purchase products from manufacturers with API 5CT certification.
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