Difference Between J55 And K55 Material Oil Casing Pipe

The oil casing is a large-diameter pipe that acts as a fixed oil and gas well wall or wellbore. The casing is inserted into the wellbore and fixed with cement to prevent the wellbore from separating the formation and the wellbore from collapsing, and to ensure that the drilling mud circulates for drilling.

Casing pipe is the lifeline for maintaining oil well operations. Due to different geological conditions, the state of the downhole is complicated, and the combined action of tension, compression, bending and torsion stress acts on the pipe body, which puts high requirements on the quality of the casing itself. Once the casing itself is damaged for some reason, it may result in a reduction in production and even scrapping of the entire well. According to the strength of the steel itself, the casing can be divided into different steel grades, namely J55, K55, N80, L80, C90, T95, P110, Q125, V150 and so on. The well conditions and well depth are different, and the steel grades used are also different. The casing itself is also required to have corrosion resistance in a corrosive environment. Casing is also required in places with complex geological conditions with anti-squeezing properties. Casing end machining form: short round thread, long round thread, trapezoidal thread, special buckle, etc. It is mainly used for oil well drilling mainly for supporting the well wall during and after drilling to ensure the drilling process and the normal operation of the entire well after completion.

K55 and J55 refer to the steel grade of the steel used for the oil casing. Different grades of steel, the physical properties of the pipe body are different, mainly including compression resistance, torsion resistance and corrosion resistance, eclipse and other properties. These two indicators are the materials used to identify the casing and cannot indicate their model number. K55 has the same chemical composition as J55 except that the tensile strength is different. The tensile strength of J55 has a minimum tensile strength of 517 MPa, and the minimum tensile strength of K55 is 615 MPa.

There are many kinds of oil casing materials. The basic ones are ordinary carbon steel, J55, L80, N80, P110, etc., and then special materials, such as 3Cr, 9Cr, 13Cr, 22Cr, etc., mainly anti-carbon dioxide and anti-defense. Hydrogen sulfide materials, such as 90SS, 95SS, etc. In addition, higher levels, as well as nickel chrome alloy pipes, according to different manufacturers, different numbers and some special needs, such as high anti-extrusion materials, some manufacturers will add TT to indicate anti-squeezing.

Oil casing pipe is used to support oil and gas well wall steel pipe. In order to ensure the normal operation of the entire well after the drilling process is completed and completed.

Each well is based on different depths of drilling and geology, using several layers of casing. After the casing is down, the cement is cemented. It is different from the oil pipe and the drill pipe.Can not be reused, is a disposable consumable material.

Therefore, the consumption of casing accounts for more than 70% of all oil well pipes.

Casing can be divided into: conduit, surface casing, technical casing and oil casing.

The important position of the oil pipeline
The oil industry is an industry that uses a large number of oil pipes. Oil pipes play an important role in the oil industry:
1.The use of oil pipes is large and costly, and the potential for cost savings and cost reduction is enormous. The consumption of oil well pipes can be calculated based on the annual drilling scale. According to the specific conditions of China, 62kg of oil well pipe is required for every 1m drilled, including 48kg casing and 10kg oil pipe. Drill pipe 3kg, drill collar 0.5kg;
2.The mechanics and environmental behavior of oil pipelines have an important impact on the adoption of advanced processes and increased production and efficiency in the petroleum industry;
3.The loss of oil pipelines is huge, and safety and reliability and oil life are of great importance to the petroleum industry.