The application field of a pipe product decides the grade, the coating, the testing and the budget, and Maintenance and Reliability Strategies for L360 (X52) Pipelines is where that decision is made. This article maps the typical applications, the conditions that govern them, and the selection logic behind each one.
Line pipe moves oil, gas and water between fields and markets.
Casing and tubing line and complete oil and gas wells.
Process plants select pipe by line class, temperature and corrosivity.
Boiler and heat exchanger tubes follow A192/A213/A556 families.
Structural and piling pipe is ordered on section properties, not pressure.
Oil and Gas Transmission
The core application of line pipe is transporting crude oil, natural gas and refined products between fields, processing plants and markets. The operating pressure, the corrosivity of the fluid and the terrain decide the grade (from Grade B to X70), the wall thickness, the coating system and the testing level. Long-distance gas lines run at 6 to 12 MPa and above, which is why they use the higher X-grades with PSL2 testing.
Water and Slurry Pipelines
Water transmission, irrigation and slurry pipelines carry lower pressure but large volumes, and they dominate the large-diameter welded pipe market. Grades B to X52 in ERW or SAW construction cover most of this service, with internal cement or epoxy lining and external FBE or 3LPE coating depending on water chemistry. Slurry service adds abrasion considerations to the lining choice.
Oil and Gas Wells: Casing and Tubing
Downhole, casing and tubing support the well and carry production. Grades from H40 to T95 and beyond are selected for collapse, burst and tension loads, temperature and sour service, with API 5CT as the governing standard. The connection type is as important as the pipe body, because the well integrity depends on the threaded joints.
Petrochemical and Process Plants
Refineries and chemical plants use carbon steel pipe to A106 and API 5L for process lines, and stainless and alloy pipe for corrosive and high-temperature service. The piping code, such as ASME B31.3, sets the allowable stresses and the material requirements, and the pipe is selected for the design pressure, temperature and fluid corrosivity of each line class.
Power Generation and Boilers
Boiler and heat exchanger tubing operates at high temperature and pressure, and is supplied to standards such as ASTM A192/SA192, A213 and A556. The low alloy and stainless grades in these standards provide creep strength and oxidation resistance at steam temperatures, with the chemistry and heat treatment chosen for the metal temperature of each section.
Structural, Piling and General Engineering
Steel pipe is also a structural section: piles for foundations, columns, handrails, conveyors and temporary works. Structural tube to ASTM A500 and piling pipe to API 5L or EN standards carry loads rather than pressure, and the selection focuses on section properties, wall thickness and end preparation for welding or driving.
Frequently Asked Questions
Depends on pressure, diameter and terrain: X52 to X70 are common for mainlines, with PSL2 and impact testing for fracture control.
Yes. API 5L grades B to X52 are widely used for water transmission, usually with internal lining and external coating.
Casing and tubing (API 5CT) line and complete oil and gas wells; line pipe (API 5L) transports fluids above ground or in buried transmission systems.
ASME B31.3 governs process piping design and lists the acceptable pipe standards such as ASTM A106 and API 5L.
When the fluid corrodes carbon steel, when hygiene is required (food, pharma), or when the temperature exceeds the carbon steel service range.
Large-diameter steel pipe driven into the ground to support foundations; it is ordered by structural requirements and often supplied to API 5L or EN standards.
