There are many types of steel pipes commonly used in oil and gas pipelines. The following are some of the main types and their characteristics and application scenarios:

Seamless steel pipe

Features

High pressure bearing capacity: produced by hot rolling or cold drawing process, without welds, uniform overall structure, with high strength and pressure bearing capacity, able to withstand high internal pressure and external loads.

Good corrosion resistance: the material is usually high-quality carbon steel or alloy steel. After proper heat treatment and surface treatment, it has good corrosion resistance and can adapt to different conveying media and environmental conditions.

High dimensional accuracy: the outer diameter and wall thickness of the steel pipe have high dimensional accuracy, which can ensure the sealing and installation quality of the pipeline connection and reduce the risk of leakage.

Smooth inner wall: the inner surface is smooth and the fluid resistance is small, which is conducive to the smooth transportation of oil and natural gas and can reduce the energy loss during the transportation process.

Application scenario: commonly used in high-pressure and high-temperature oil and gas pipelines, such as gathering pipelines inside oil and gas fields, key parts of long-distance pipelines, process pipelines of refineries and natural gas processing plants, etc.

Straight seam submerged arc welded steel pipe (LSAW)

Features

High production efficiency: The straight seam welding process is adopted, and the production speed is fast, which can meet the needs of large-scale pipeline construction.

Good weld quality: Submerged arc welding technology is used in the welding process, the weld has a large penetration depth, stable quality, high strength and toughness of the weld, and can effectively ensure the overall performance of the pipeline.

Wide range of pipe diameters: It can produce steel pipes with larger diameters, the diameter is generally above 600mm, and the maximum can reach about 4000mm, which is suitable for large-flow oil and natural gas transportation.

Relatively low cost: Compared with seamless steel pipes, the production process is relatively simple and the cost is low. On the premise of meeting engineering requirements, it has a high cost performance.

Application scenarios: Widely used in long-distance oil and natural gas transmission pipelines, urban gas trunk pipelines, oil and gas transmission pipelines in large industrial projects, etc.

Spiral seam submerged arc welded steel pipe (SSAW)

Features

Flexible manufacturing process: Through the spiral welding process, steel pipes of different diameters and wall thicknesses can be produced according to needs. The width requirements of raw materials are relatively low, and steel resources can be fully utilized.

Long weld length: The spiral weld makes the stress distribution at the weld more uniform when the steel pipe is under pressure, which can effectively improve the bearing capacity of the steel pipe and adapt to a certain degree of pressure fluctuations and external forces.

Good comprehensive performance: It has good strength, toughness and corrosion resistance, and can meet the transportation requirements of oil and natural gas under general working conditions.

Obvious cost advantage: The production efficiency is high and the cost is relatively low. It has high economy when the pipe diameter is large and the pressure requirement is not particularly high.

Application scenario: It is commonly used in medium and low pressure long-distance oil and natural gas pipelines, such as some regional oil and gas pipelines, gas pipelines around cities, etc.

Stainless steel pipe

Features

Extremely strong corrosion resistance: It contains alloy elements such as chromium and nickel, and can form a dense oxide film on the surface. It has excellent corrosion resistance and can resist the erosion of various corrosive media such as acids, alkalis, and salts.

Good high temperature resistance: It can still maintain good mechanical properties and stability in high temperature environments, can withstand high working temperatures, and is suitable for transporting high-temperature oil and natural gas or using in high temperature environments.

Excellent hygienic performance: the material is pure, no harmful substances are precipitated, and it will not pollute the transported oil and natural gas. It is particularly suitable for occasions with high requirements for the quality of the transported medium.

Beautiful and durable: the surface is smooth, the appearance is beautiful, and it has a long service life, which can reduce the maintenance and replacement costs of the pipeline.

Application scenarios: It is mainly used in oil and gas pipelines with high corrosion resistance and sanitation requirements, such as process pipelines of offshore oil and gas field platforms, pipelines for transporting highly corrosive oil and gas, special process pipelines in natural gas purification plants and refineries, etc.

Composite steel pipe

Features

Superior comprehensive performance: Steel pipes of different materials are combined together through a composite process, such as stainless steel composite steel pipes, carbon steel and alloy steel composite steel pipes, etc., which have the advantages of different materials, and have both the high strength and high toughness of the outer steel pipe, and the corrosion resistance or other special properties of the inner steel pipe.

Strong customizability: According to different engineering requirements, different material combinations and composite processes can be selected to meet specific transport media, environmental conditions and process requirements.

Better cost-effectiveness: In some occasions with high requirements for corrosion resistance and strength, compared with all-stainless steel or all-alloy steel pipelines, composite steel pipes can reduce costs while ensuring performance.

Application scenarios: Suitable for transporting oil and natural gas with corrosive, abrasive or other special requirements, such as oil and gas pipelines containing corrosive media such as hydrogen sulfide and carbon dioxide, submarine oil and gas pipelines, oil and gas field produced liquid transportation pipelines, etc.

In addition to the above-mentioned steel pipe types, there are also the following commonly used steel pipes in oil and gas pipelines:

Double-layer fusion-bonded epoxy powder coated steel pipe

Features

Excellent anti-corrosion performance: A double-layer fusion-bonded epoxy powder coating is applied on the surface of the steel pipe to form a solid and continuous anti-corrosion protective film, which can effectively block external moisture, oxygen and corrosive substances, and has good chemical corrosion resistance and soil corrosion resistance.

Strong adhesion: The coating has high adhesion to the surface of the steel pipe, and is not easy to fall off or peel. Even when the pipeline is deformed to a certain extent by external force, the coating can remain intact and continue to play an anti-corrosion role.

Good wear resistance: The coating has high hardness and toughness, can resist the erosion of solid particles in the conveying medium and the friction between the pipeline and external objects during the laying and use of the pipeline, and reduce the impact of wear on the pipeline.

Excellent insulation performance: It can effectively prevent electrochemical corrosion of the pipeline and reduce the risk of corrosion. At the same time, it can also reduce the interference of stray current on the pipeline and improve the safety and stability of the pipeline.

Application scenarios: It is widely used in oil and natural gas pipelines in various environments, especially in areas with strong soil corrosion, such as saline-alkali land, swamps, etc., as well as submarine pipelines and urban underground gas pipelines with high anti-corrosion requirements.

Polyethylene anti-corrosion steel pipe

Features

Good anti-corrosion performance: Polyethylene is used as the anti-corrosion coating material. Polyethylene has good chemical stability and water resistance, which can effectively prevent the steel pipe from contacting with external corrosive media and protect the steel pipe from corrosion.

Strong impact resistance: The polyethylene coating has high flexibility and impact resistance, can withstand the external force impact of the pipeline during installation and use, is not easy to break or damage, and plays a good protective role for the steel pipe.

Good weather resistance: It can adapt to different climatic conditions. Under the influence of environmental factors such as high temperature, low temperature, and ultraviolet rays, it has stable performance, is not easy to age, and can maintain good anti-corrosion effects for a long time.

Convenient construction: The coating of polyethylene anti-corrosion steel pipe can be pre-processed in the factory. Only pipeline connection is required during on-site installation. The construction speed is fast and efficient, and the repair and maintenance of the coating are relatively simple.

Application scenarios: It is commonly used in urban gas pipelines, heating pipelines, and some oil and natural gas gathering and transportation pipelines with high anti-corrosion requirements. It is especially suitable for buried pipelines, which can effectively extend the service life of the pipeline.

Glass fiber reinforced plastic composite steel pipe (FRP)

Features

Excellent corrosion resistance: It is composed of materials such as glass fiber and resin, has excellent corrosion resistance, and has good resistance to various chemical media such as acid, alkali, and salt. It is especially suitable for transporting highly corrosive oil and natural gas.

Light weight: Compared with traditional steel pipes, FRP pipes are much lighter, easier to transport and install, and can reduce construction difficulty and cost. Especially in some areas with inconvenient transportation or complex construction conditions, its advantages are more obvious.

Good insulation performance: It has good electrical insulation performance, which can effectively prevent electrochemical corrosion and the influence of stray current, and can also avoid static electricity accumulation during the operation of the pipeline, thereby improving safety.

Smooth inner wall: The inner surface is smooth, with low roughness and low fluid resistance, which can improve the transportation efficiency of oil and natural gas, reduce energy consumption, and is not easy to scale, which can reduce the workload of pipeline cleaning and maintenance.

Application scenarios: It is widely used in some highly corrosive oil and gas field development, process pipelines of offshore platforms, and gas pipelines in urban sewage. It is also suitable for special occasions with high requirements for insulation performance and corrosion resistance.