Seamless steel pipe
Seamless steel pipe is mainly used for transporting high-pressure oil and gas near the wellhead. In different application places, different specifications of seamless steel pipe are selected, mainly considering material, wall thickness and caliber. The thicker the wall thickness, the more economical and practical it will be, and the higher the processing cost will be.
Use of seamless steel pipe
Seamless tubes for general use are rolled from ordinary carbon structural steels, low alloy structural steels or alloy structural steels with the highest yield. They are mainly used as pipes or structural parts for conveying fluid. Three types of supply according to use:
1. Supply by chemical composition and mechanical properties.
2. Supply according to mechanical properties.
3. Water pressure test supply.
Steel tubes supplied according to class 1 or 2 shall also be subjected to hydrostatic testing if used to withstand liquid pressure. The specialized seamless tubes include seamless tubes for boiler, seamless tubes for geology and seamless tubes for petroleum.
The purpose of nondestructive testing of seamless steel tubes
1. Improve the manufacturing process to ensure product quality.
2. In the process of product manufacturing, defects can be found in advance to avoid product scrapping, so as to save labor and cost and reduce the cost of product manufacturing.
3. Improve the reliability of products, ensure the safety of products and avoid accidents. Apply NDT to the design, manufacture, installation, use and maintenance of products. Through a series of tests, determine the design, raw materials, manufacturing process and operation of good or bad, and find out the factors that may cause damage, and then improve, so as to improve the reliability of the product.
Method for nondestructive testing of seamless steel tubes
X-ray inspection, ultrasonic inspection, magnetic particle inspection, penetration inspection, eddy current inspection. In addition, there are leakage detection, acoustic emission detection, stress testing, visual inspection and so on.
NACE seamless steel pipe Anti-hydrogen crack /HIC
With the increasingly serious problem of hydrogen sulfide corrosion, the development of anti-sulfur seamless pipeline is extremely urgent, and the quality of anti-sulfur performance is the key. The demand of domestic and foreign seamless pipeline against sulfur is increasing. Seamless pipe is mainly used for transporting high pressure oil and gas near the wellhead.
The factors of medium and material affecting the anti-hydrogen-induced crack (HIC) performance were discussed. It was concluded that the addition of Cu and Ni could improve the HIC performance of seamless pipeline materials, reduce the content of S in steel, and reduce the sensitivity of hydrogen bubbling after the treatment with silicon-calcium powder.
