The most reliable way to distinguish seamless (SMLS) pipe from electric resistance welded/high-frequency welded (ERW/HFW) pipe is to combine physical inspection with product marking and mill documentation. A longitudinal weld indication can suggest ERW/HFW manufacture, but visual appearance alone is not always conclusive because modern weld seams may be trimmed, heat treated and covered by coating. How Seamless and ERW Pipes Are Manufactured Seamless Pipe Seamless pipe is produced from solid steel starting material that is pierced and rolled or…

For a steel pipe pile foundation, the basic quantity calculation starts with outside diameter (OD), nominal wall thickness (t), pile length (L) and number of piles (N). The most useful purchasing calculation is the theoretical mass per meter of a circular steel pipe, followed by the total ordered length. Any allowance for cutting, splicing or contingency should be project-specific rather than treated as a universal percentage. ASTM A252/A252M Steel Pipe Piles ASTM A252/A252M-26 covers nominal-wall cylindrical steel pipe piles used…

Yes. ERW (electric resistance welded) steel pipe can be welded during fabrication or field installation when the material, joint design, welding procedure and inspection requirements are suitable for the project. The key is not simply whether the pipe already contains a longitudinal ERW seam, but whether the girth weld or attachment weld is made under a qualified procedure appropriate to the pipe grade, wall thickness, chemistry and service conditions. ERW Pipe Weldability How ERW Pipe Is Made—and Why It Matters…

API 5L Grade B, also designated L245, is one of the most widely specified line-pipe grades for oil, gas, water and related pipeline transportation systems. Its popularity comes from a practical balance of strength, weldability and availability. However, a correct purchase order requires more than the words “API 5L Grade B.” Buyers also need to define the Product Specification Level (PSL), dimensions, manufacturing route, delivery condition, inspection requirements, coating and certification. API published the 47th Edition of API Specification 5L…

API 5L Grade B pipe, also designated L245, is widely considered for oil and gas transportation systems where its specified strength, dimensions and service requirements fit the design. With a specified minimum yield strength of 245 MPa and minimum tensile strength of 415 MPa, Grade B can provide a practical balance between material performance, weldability and project cost. It does not, however, have a universal pressure rating or automatic suitability for sour, offshore or low-temperature service. API published the 47th…

API 5L line pipe is widely used for crude oil, natural gas and other energy-transportation pipelines because it provides a common manufacturing specification for seamless and welded steel line pipe. For an oil transmission project, however, selecting “API 5L” is only the starting point. Grade, PSL, wall thickness, manufacturing route, toughness, corrosion protection, inspection and documentation must all be matched to the design basis. API published the 47th Edition of API Specification 5L in June 2026. The edition includes updates…

Customized structural hollow sections are selected primarily by cross-sectional geometry, load path, connection design, manufacturing route, and the governing structural standard. Under EN 10219, the most familiar profiles are Circular Hollow Sections (CHS), Square Hollow Sections (SHS), and Rectangular Hollow Sections (RHS); EN 10219-2:2019 also covers elliptical hollow sections. Each geometry behaves differently under bending, compression, torsion, and connection loading, so “customized hollow section” should describe an engineering choice rather than simply a non-standard size. For LONGMA customers, one product…

Fusion-bonded epoxy (FBE) coating is widely used to protect steel pipe from external corrosion in buried or submerged service. For procurement teams, however, specifying an FBE-coated pipe is only the first step. The coating must also be inspected and tested under a documented inspection and test plan (ITP) to verify thickness, continuity, adhesion, cure, and resistance to cathodic disbondment. A coating that looks uniform can still contain holidays, local under-cure, poor surface preparation, or adhesion defects that may shorten field…

Bending galvanized steel pipe properly is a skill that directly impacts pipe integrity, coating longevity, and long-term project performance. Galvanized steel pipes are carbon steel pipes that have been coated with a protective coating of zinc by hot-dip galvanizing. The pipes are usually made to ASTM A53 requirements. Zinc coating offers a barrier and cathodic protection. Incorrect bending techniques may cause cracking or delamination of the zinc coating, which can lead to rapid corrosion of the steel substrate. This handbook leads…

When distributors are stocking ASTM A500 structural tubing for the North American market, one question appears frequently: Is Grade B the safer inventory choice, or is Grade C the better option? Neither grade is universally better. For round structural tubing, Grade C provides higher specified minimum yield and tensile strength, while Grade B may remain appropriate where its mechanical properties satisfy the design. The correct selection depends on structural calculations, project specifications, fabrication requirements, availability, and total procurement cost. Understanding…

Galvanized steel pipe has a long history in water-distribution and building-plumbing systems, but the answer to whether it is suitable for drinking water is not a simple yes or no. Suitability depends on local plumbing codes, the age and condition of the pipe, water chemistry, corrosion behavior, and the health-effects certifications required for materials that contact potable water. ASTM A53/A53M addresses steel pipe product requirements; it should not be treated as a substitute for potable-water health-effects certification. Understanding Galvanized Steel…

You can weld galvanized steel pipe, but it calls for thorough preparation and strict adherence to safety procedures. Galvanized pipe's corrosion protection comes from a zinc covering, which vaporizes at welding temperatures, emitting poisonous zinc oxide fumes and possibly affecting weld integrity. ASTM A53-2024 sets minimum zinc coating weights for hot-dip galvanized pipe, and any welding procedure that burns through that layer causes a health concern as well as a corrosion susceptibility at the connection. No serious fabrication or procurement…

The repercussions of a premature failure of a subterranean pipeline may be much more than repair expenses, including project delays, environmental liabilities, and reputational harm. That is why the endurance of an FBE coated pipe is not a supplementary quality but the backbone of any long-term infrastructure project. Fusion bonded epoxy coating provides a chemically cross-linked continuous barrier over the steel substrate that offers protection for pipeline service lifetimes in excess of 50 years in harsh soils and submerged situations. This…

When a pipeline crosses corrosive soil, saltwater marshland or an industrial zone, pipe manufacture and external corrosion protection must be specified separately. ERW describes how the steel pipe is formed and welded; FBE describes a protective coating that can be applied to ERW pipe. This article therefore compares bare ERW pipe with FBE-coated ERW pipe so procurement engineers, EPC contractors and project managers can evaluate the additional corrosion-control function and lifecycle implications. Understanding Bare ERW and FBE Coated ERW Pipe…

ASTM A500 covers cold-formed welded and seamless carbon steel structural tubing in round and shaped cross-sections. This article focuses on round ASTM A500 structural pipe because LONGMA's manufacturing and supply scope is welded round pipe produced by ERW and LSAW processes. Square and rectangular HSS are within the standard's broader scope but are not included in LONGMA's product offering. ASTM A500 Grades and Mechanical Properties ASTM A500 includes Grades A, B, C and D. Grades B and C are the…