The Materials For Oilfield Steel Pipe

Oilfield Equipment and supplies need durable steel pipe to perform the tasks needed on site. For example, tubing strings and casing are often subjected to hundreds or even thousands of atmospheric pressures, hundreds of tons of tensile loads, high temperatures and severe corrosive media. The life of the casing directly determines the life of oil well, which in turn determines the life of the oilfield. According to the U.S. Department of Energy, the average global well depth for oil and gas has doubled since 1978 and continues to grow rapidly. With the increase of well depth and temperature and pressure, many new and higher requirements are put forward for well pipes.

Pipe that is not resistant to corrosion will deteriorate over time, reducing efficiency and causing downtime for operations, crumbling pipes may lead to safety hazards and increase the costs of responding to an emergency. Here are some of the best materials to protect your investments with a high-quality industrial steel pipe. Oilfield steel tubing and fittings must meet ASME, ASTM and API standards for tightness and capability to resist oil or corrosive chemical. Stainless steel is a good option for pipes because it's corrosion and rust-resistant.

The design life of oil and gas field pipeline material should be 15 years, and that of long-distance pipeline should be 30 years. The design is in accordance with ASME B31.3 and other standard codes. The size series of pipeline material should be ASME B36.10m or ASME B36.19m, API 5L. The selection of pipeline materials shall be based on the design conditions such as pipeline grade, design temperature, the actual H2S and CO2 content of the medium, the flow rate of the medium and the temperature of the medium, as well as the processing performance, weldability and economy of the material. When buying steel pipe casings, consider a design that enhances the integrity and durability of the equipment. Low-e coating provides protection from abrasions, rust and corrosion. Corrosion resistance is enhanced by the use of an electrochemical resistant lining. Certain metals are more suitable for the application of polyethylene liners because they can be painted to match any color of concrete, paving or flooring.

For the transport of toxic, flammable, explosive gas medium, the highest working pressure of the long-distance pipeline > 4.0MPa; The long distance pipeline transporting toxic, flammable and explosive liquid medium, with the highest working pressure ≥ 6.4mpa and the conveying distance ≥200km, shall not use fluidized bed steel and carbon structural steel, but shall use PSL2 grade, high purity, fine grain (grain size ≥8 grade) fully killed steel, among which, L485(X70)and above steel grade shall use acaricidal iron-type killed steel. The refining requirements of this kind of steel are put forward for the use of oil and gas long-distance pipeline. For steel grade not less than L360M/X52M, pipe diameter range of 508 mm ~ 1219 mm, should also be carried out drop weight tear test; According to the design requirements, the toughness and brittleness transition curve of shear area for transverse drop weight tear test of pipe body made by oilfield pipeline manufacturer shall at least contain the following test temperatures: 20℃, 0℃, -10℃, -20℃, -40℃.

For industrial pipelines, namely conveying fluid medium and design pressure ≥10.0MPa, or design pressure ≥4.0MPa, and design temperature ≥400℃ pipeline. PSL2 grade pipeline steel shall be used in the main pipeline of long distance transportation and oil and gas field and combustible medium, and suitable pipes, such as PSL2 steel pipe, can be selected according to the physical properties and risk of the medium for other medium pipelines. The design temperature is lower than or equal to -20℃ low temperature pipe steel, in addition to the carbon content is less than or equal to 0.10%, and conforming to the standard of chrome-nickel austenitic stainless steel in the material use temperature is not less than -196℃ Charpy impact test, the rest of the steel should be Charpy (V-notch) low temperature impact test.

Cryogenic piping of ASTM material shall be designed in accordance with ASME B31.3. This test is not required for piping above -20℃.

The material used in transporting corrosive medium pipelines should have corrosion resistance. In addition to intergranular corrosion and other local corrosion, generally can be selected according to the corrosion rate of the medium to metal materials. Medium for oil, natural gas, steam, condensed water, boiler feed water and other water medium materials, when the pressure grade CL150, CL300, CL600, API 5L carbon steel pipe, pressure grade ≥CL900, ASTM A106 GR.B, API 5L pipe. Stainless steel, cr-mo steel materials, low temperature carbon steel or low temperature stainless steel for almost all pressure classes.

In addition, it should be noted that steel tubes with a carbon content greater than 0.30% should not be welded steel tubes. Seamless steel pipe using hot forming, normalizing treatment such as L245N (GR.b), L345N; HFW and SAW steel tubes are made of hot mechanical strip and cold forming process, such as L360M(X52M). 

1) Nominal diameter of pipe shall be selected in accordance with ASME B36.10m.

2) Pipe wall thickness of gb materials shall be in accordance with ASME B31.3.

3) For carbon steel and low alloy steel pipes, the outside diameter and wall thickness series shall be ASME B36.10m. For austenitic stainless steel and non-ferrite metal pipes, the outer diameter and wall thickness series shall be in accordance with ASME B36.19m and ASME B36.10m standards.

4) Conveying extremely dangerous media, or high pressure and temperature parameters, or under mechanical vibration, pressure pulsation and drastic changes in temperature pipeline, seamless steel pipe should be selected.

There are different types of steel pipe casings available for drilling. Some are designed to be installed inside the borehole. Others are used outside the hole to support the concrete stem as it moves through the hole. Steel pipes can also be set inside the borehole. These are called "cavity set inside" or "cavity set outside and open face. Different types of steel pipe are used in different drilling operations. Gas and oil drilling requires a steel pipe stem that's flexible enough to allow drilling but that won't fatigue during long hours of operation. Rigid stem cones are used for shallow wells and corrugated stem cones are used for deeper wells. Before deciding which type of stem you need for your well, evaluate the requirements for your drilling tube.