SMLS, ERW, LSAW, and SSAW steel pipes are the common types of steel pipes.
LSAW, SSAW, ERW, and SMLS (Seamless) pipes differ primarily in manufacturing method, strength, and application.
- SMLS has no weld, ideal for high pressure.
- LSAW (longitudinal) and SSAW (spiral) use submerged arc welding for large-diameter, high-stress projects.
- ERW (Electric Resistance Welded) is cost-effective, using electric resistance for medium-pressure, smaller diameters.
Key Differences Between SMLS, ERW, LSAW, and SSAW
| Abbreviations | SMLS | ERW | LSAW (SAWL) | SSAW (HSAW, SAWH) |
| Name | seamless pipe | Electric Resistance Welded pipe | Longitudinal Submerged Arc Welding pipe | Spiral Submerged Arc Welding pipe |
| Raw Material | steel billet | steel coil | steel plate | steel coil |
| Technique | Hot-rolled or cold-drawn | resistance welding | submerged arc welding | submerged arc welding |
| Appearance | No weld | Longitudinal weld seam, weld seam not visible | Longitudinal weld seam | Spiral weld seam |
| Common Outside Diameter(OD) | 13.1-660 mm | 20-660 mm | 350-1500 mm | 200-3500 mm |
| Common Wall Thickness(WT) | 2-100 mm | 2-20 mm | 8-80 mm | 5-25 mm |
| Prices | highest | cheaply | high | cheaply |
| Specificities | Small diameter thick wall steel pipe | Small diameter thin wall steel pipe | Large diameter thick wall steel pipe | Extra large diameter steel pipe |
| Appliance | Petrochemical, boiler manufacturing, geological drilling, and other industries | For low-pressure fluid transfer, such as water, gas, air, and steam piping | Mainly used in long-distance pipelines for the transmission of oil, natural gas, or water | Mainly used for low-pressure fluid transportation, such as water and gas pipelines, as well as for building structures and bridge elements |
SMLS steel pipe : Extreme pressures (oil, petrochemical).
LSAW steel pipe: High-pressure large diameter (petroleum transport).
SSAW steel pipe: General pipelines, structure, pile driving.
ERW steel pipe: Low/medium pressure, fluid transport, structural scaffolding.
How To Order Steel Pipe For Your Project
When ordering steel pipes, there are two key dimensions: the nominal pipe size (NPS) and the wall thickness (schedule).
Pipe lengths can be single random (SRL) 5-7 meters for pipes below 4 inches or double random length (DRL) 11-13 meters above 4 inches. Custom lengths can be used for long pipelines. Pipe ends can be bevelled (BE), plain (PE), threaded (THD) threaded and coupled (T&C) or grooved.
Typical Order Details Summary:
- Type (Seamless or welded)
- Nominal Pipe Size
- Schedule
- End types
- Material Grades
- Quantity in meters or feet.
At Rayoung, we can help supply the steel pipe you need for any project. We are proud to offer a range of high-quality steel products, including seamless, ERW, LSAW and SSAW pipes.
If you need to find steel pipe, contact us, and our friendly team can guide you through the entire process.
