Oil Casing Pipe Testing Method

Oil casing is a high-end product of steel pipe production. There are many types of casings, with a total of 15 casing diameter specifications. The outer diameter range is 114.3-508mm; there are 11 types of steel, including J55 pipe, K55 pipe, N80 pipe, l-80, P-110, C-90, c-95, t-95, etc.; there are many kinds of requirements for the end button type of casing pipe, and the button type of STC, LC, BC, VAM, etc. can be processed. The production and installation process of petroleum casing involves many tests, mainly including the following points:


1. Ultrasonic test
When the ultrasonic wave propagates in the material to be tested, the change of acoustic characteristics and internal structure of the material will affect the ultrasonic wave propagation. The degree and condition of ultrasonic testing are used to understand the change of material performance and structure.
2. Radiographic testing
X-ray examination uses the difference of radiation transmitted between the normal part and the defective part, which leads to the difference of substrate blackness.
3. Penetration test
Penetration test is to use the capillary action of liquid to penetrate the penetrant into the open defects on the surface of solid materials, and then attract the penetrant to the surface through the developer to show the existence of defects. Suitable for all kinds of metal and ceramic workpieces, the time from infiltration operation to defect display is relatively short, usually about half an hour, surface fatigue, stress corrosion and welding cracks can be detected, and the crack size can be directly measured.
4. Magnetic particle test
Magnetic particle testing uses the leakage flux at the defective part to absorb magnetic particles and form magnetic marks to provide indication of defects. It can detect surface and sub surface defects. The nature of the defect is easy to identify.  Paint and electroplated surfaces do not affect the detection sensitivity.
5. Eddy current test
Eddy current test mainly uses the eddy current induced by ferromagnetic coil in the workpiece to analyze the internal quality of the workpiece. It can detect surface and near surface defects of various conductive materials. Generally, parameter control is very difficult, test results are difficult to interpret, and test objects are needed. It must be a conductive crack and indirectly measure the length of the defect.
6. Magnetic flux leakage detection
Magnetic flux leakage detection of oil casing is based on the high permeability of ferromagnetic materials. The quality of the in-service oil sleeve can be detected by measuring the change of permeability caused by defects in ferromagnetic materials.
7. Magnetic memory test
Magnetic memory testing is the relationship between the physical properties of magnetic phenomena and the process of metal dislocation. It has many advantages, such as high efficiency, low cost, no grinding and so on. It has an important and broad application prospect in industry.
Among several testing methods, there is no specific standard for product magnetic memory testing, which needs to be developed. The other six types have their own testing standards and are relatively mature