Collapse Resistant Casing

Among all kinds of casings, anti-collapse casing is the one to go down to the deepest place of well. Thus there are the highest requirements for its mechanical properties and sealing performance. Collapse resistant casing is extensively used for deep or ultra deep wells, oil and gas wells that need isolate halite layer, soft mud layer and other complex stratums, and H2S corrosion resistant wells. Its steel grades include K55, N80, P110, Q125, V150, etc. The main specifications of anti-collapse oil casing cover 177.8 mm (7in), 168.28 mm (6-5/8in), 139.7 mm (5-1/2in), 127 mm (5in), 114.3 mm (4-1/2in), etc. JST collapse resistant casing is manufactured in strict accordance with API 5CT standards with high dimension precision. We mainly adopt continuous rolling pipe production. The mechanical property, impact, hardness and performance of this anti-collapse casing fully meet the requirements of users’ technical conditions. The pipe end processing forms include plain end, short round thread, long round thread and buttress thread.

1. Rounding Diameter and Small Ovality (≤ 0.5%)
JST adopts advanced rolling equipment for anti-collapse oil casings, such as φ140Assel pipe mill, annular furnace, conical puncher, Assel tube mill, 14 three-roll micro tension sizing mill, and so on. Featuring fast rolling speed, this machine unit makes the wall thickness of hollow billet reduce and extend, makes the pipe wall thickness is equal to the dimension of the finished collapse resistant casings, and eliminates the uneven wall thickness in the longitudinal direction. After sizing, the anti-collapse casing has small diameter deviation, small ovality, good straightness and smooth surface.
2. High Wall Thickness Precision and Uniform Performance (Inequality of the Same Section Non-Uniformity ≤ 9.5%)
a. After pipe rolling, we use 14 three-roll micro tension sizing mill for sizing and six roll straightening machine for straightening, which ensures uniform wall thickness of collapse resistant casings.
b. JST anti-collapse casing features high strength, uniform structure and stable performance. It is made from pure steel (P ≤ 0.020%, S ≤ 0.010%). The control accuracy of furnace temperature in the heat treatment process is equal or less than 5℃.
c. We use the vortex (eddy current), magnetic flux leakage, ultrasonic, hydrostatic testing and other testing equipment to inspect collapse resistant casings. JSJ also adopts artificial surface inspection to ensure high quality and stable performance of our anti-collapse oil casings.
3. Low Residual Stress
After heat treatment high-temperature tempering, we adopt thermal straightening and the final straightening temperature is controlled equal or more than 450℃. JST heat treatment production line is configured with online quick straightening machine and British imported UNICORN joint inspection machine that do straightening and inspection for the collapse resistant casing after heat treatment. We ensure to provide high quality anti-collapse casings for our clients.
4. JST casing thread production line is equipped with petroleum head and end threads. It features coupling twist knot, hydrostatic testing, pipe end thread sandblasting, overall length measurement and weighing. After stenciling or spray marking and oil coating, we package this product. JST has processed 80,000 tons of collapse resistant casings (φ140-340 mm).

Technical Parameters Parameters of collapse resistant casing refer to the EXCEL table.

JAT has strict rules for spray marking of our anti-collapse casings as follows:

• For Grade J55/K55 casing, we spray a green chromatic circle at the pipe end.
• For Grade N80-1 casing, we spray a red chromatic circle at the pipe end.
• For Grade N80-Q collapse resistant casing, we spray a red chromatic circle and a green chromatic circle at the pipe end.
• For Grade L80-1 anti-collapse oil casing, we spray a brown chromatic circle at the pipe end.
• For Grade P110 casing, we spray a white chromatic circle at the pipe end.
• For Grade N80-1 casing, we spray a red chromatic circle at the pipe end.

Packaging and Transportation1. We use steel wire or steel strip to tie the collapse resistant casing up and use pipe cap to protect the pipe ends.

2.JST anti-collapse casings are transported in bulk or container. Customers can choose land transportation or water transport.

Jiangyin Changjiang Steel Tube Making Factory is a leading supplier and exporter of collapse resistant casings in China. Our company is a large scale enterprise possessing the production capacity of 600,000 tons of special seamless steel pipes. We mainly manufacture structure pipe, fluid pipe, high pressure boiler pipe, API pipe, marine pipe, alloy pipe, tubing, line pipe, etc. Our anti-collapse casings have been exported to the Middle East, CIS, Southeast Asia, Africa, South America, North America, Europe, Australia and many other countries and regions.

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