News - Understanding the Difference Between ERW, SSAW, and DSAW Steel Pipes

Steel pipes play a crucial role in the infrastructure of today’s society from oil and gas pipelines to water delivery and structural applications. Among them, the most popular are the ERW welded pipe, SSAW steel pipe, DSAW steel pipe. Awareness of the differences between these products enables engineers, contractors and buyers to select the best pipe for their applications.

ASTM A671 CC65 CL 12 EFW Steel Pipes for Industrial & Structural Applications (1)

What is ERW Steel Pipe?

ERW steel pipe refers to a steel pipe that is constructed using electric resistance welding. This results in the formation of a longitudinal seam along the length of the pipe.

The following are some of the important salient features of ERW pipes:
Diameter: Small to medium (usually 10 mm – 508 mm).
Wall Thickness: Thin to medium (typical thickness ≤20 mm).
Applications: For water pipelines, gas pipelines, and structural and mechanical parts.
Benefits: High dimensional accuracy, smooth internal surface, economical.
Limitation: Not applicable for ultra high pressure service.

What is SSAW Steel Pipe?

SSAW (Spiral Submerged Arc Welded) steel pipe, also called HSAW, is made by rolling a steel strip into a spiral shape and welding the seam using submerged arc welding.

Key features of SSAW pipes:
Diameter: Medium to very large (400 mm–3600 mm+).
Wall Thickness: Thin to medium (≤25 mm common).
Seam: Spiral seam at an angle to the pipe axis.
Applications: Oil and gas pipelines, water transportation, large structural projects.
Advantages: Can produce large diameters and flexible wall thickness.
Limitations: Spiral seam slightly reduces pressure strength compared to longitudinal DSAW pipes.

What is DSAW Steel Pipe?

DSAW steel pipe (Double Submerged Arc Welded) is the same as LSAW (Longitudinal Submerged Arc Welded) pipe which is made by bending steel plate ~1/2 inch to 3 inches thick into a cylinder and welded both the inside and outside seams using a submerged arc welding process.

Main features of DSAW pipe:
Diameter: Medium to large (300–2500 mm standard).
Thickness of wall: Medium to thick (≥6 mm to 50 mm+).
Use: High pressure oil and gas pipelines and offshore pipelines, structural applications that require high strength.
Benefits: The seams are strong and reliable, making the material ideal for high-stress situations.
Disadvantages: Expensive production and slower production process at compared with ERW and SSAW.

ERW vs SSAW vs DSAW: Quick Comparison

Feature	ERW	SSAW	DSAW
Seam Type	Longitudinal	Spiral	Longitudinal (inside & outside)
Welding Method	Electric Resistance	Submerged Arc	Submerged Arc
Diameter Range	Small to Medium	Medium to Very Large	Medium to Large
Wall Thickness	Thin to Medium	Thin to Medium	Medium to Thick
Pressure Rating	Low to Medium	Medium	High
Typical Use	Water, Gas, Mechanical	Oil & Gas Pipelines	High-Pressure Pipelines, Offshore

Services of China Royal Steel Group

China Royal Steel Group is a professional manufacturer of steel pipe products with ERW (Electric Resistance Welded), SSAW (Spiral Submerged Arc Welded) and DSAW (Double Submerged Arc Welded) steel pipes among others. Based on years of industry experience, the company offers full technical consultation and advice on the most appropriate type of pipe for use in oil and gas transmission, water transmission, high pressure industrial operations, and vascular projects, among other applications.

Royal Steel Group considers various factors such as pipe size, wall thickness, material grade, pressure class, corrosion resistance, and environmental conditions to identify the best-fit solutions. Moreover, China Royal Steel Group provides tailored fabrication service and coating service (i.e. anti-corrosion, galvanization, epoxy lining) and stringent quality assurance with international standard of ASTM, ISO and API.

Through advanced manufacturing, precision testing and logistics support, the company is able to provide steel pipe products that comply with stringent safety, durability and performance standards, which in turn allows clients to deliver affordable, sustainable, and effective infrastructure solutions.

Selecting the right steel pipe depends on project requirements, diameter, wall thickness, and pressure rating:

ERW pipes: Cost-effective, ideal for small to medium diameters and low to medium pressure applications.

SSAW pipes: Suitable for large-diameter pipelines with flexible wall thickness.

DSAW pipes: Best choice for high-pressure, high-strength applications such as offshore or oil & gas pipelines.

Understanding the differences between ERW, SSAW, and DSAW steel pipes ensures optimal performance, safety, and cost-efficiency for any infrastructure project.

ROYAL GROUP

Address

Kangsheng development industry zone,
Wuqing district, Tianjin city, China.

E-mail

sales01@royalsteelgroup.com

Phone

Sales Manager: +8613652091506

Hours

Monday-Sunday: 24-hour Service

Post time: Jan-14-2026