ERW Piling Pipe

Piling pipe meaning

What is ERW steel pipe?

ERW steel pipe is a type of welded steel pipe like LSAW steel pipe and SSAW steel pipe. ERW (electric resistance welded) steel pipe is made by welding flat steel plates using high-frequency resistance heating. The steel plate is rolled into a cylindrical shape and then the edges are welded together. ERW pipe is known for its high cost-effectiveness, fast production speed and size versatility.

ASTM A252 Standard Overview

ASTM A252 is the standard specification covering nominal wall, cylindrical steel pipe piles. These pipes are primarily used for load-bearing purposes in construction, including buildings, retaining walls, bridges, ports, and more. The standard applies to both seamless and welded pipes, including ERW types.

Mechanical Properties
The mechanical properties of A252 piling pipe vary depending on the grade. The standard defines three grades, with Grade 3 offering the highest strength:

Property	Grade 1	Grade 2	Grade 3
Tensile Strength, min	50,000 psi (345 MPa)	60,000 psi (415 MPa)	66,000 psi (455 MPa)
Yield Strength, min	30,000 psi (205 MPa)	35,000 psi (240 MPa)	45,000 psi (310 MPa)

These values ensure that the steel piles can handle substantial structural loads under demanding environmental conditions.

Chemical Composition

For both seamless and ERW A252 steel piles, the maximum phosphorus content is limited to 0.050%, to control embrittlement and enhance weldability. This contributes to better performance during pile driving and under long-term load-bearing use.

Testing and Quality Control
Although hydrostatic testing is not required, mechanical tests are performed to ensure material integrity and consistency. Each manufacturing batch undergoes tensile testing, which can be conducted in either the longitudinal or transverse direction at the manufacturer's discretion.

Tensile Test Frequency: One test for every 200 lengths of pipe.

Dimensional Tolerances
To maintain reliability and structural performance, ASTM A252 sets strict limits for permissible variations:

Wall Thickness: Not more than 12.5% under the nominal thickness.

Weight per Foot: Pipe weight must not exceed +15% or -5% of theoretical calculated weight.

Outside Diameter: Must be within ±1% of the specified diameter.

These tight tolerances ensure uniformity across each batch, which is essential for seamless construction and pile driving operations.

Advantages of ERW Piling Pipes

1.ERW steel piling pipes have become the preferred choice for many contractors and engineers due to the following benefits:

2.Consistent Quality: The high-speed ERW manufacturing process ensures minimal variation in wall thickness and weld seam integrity.

3.Cost-Effective: ERW pipe production is more efficient and less expensive than seamless methods, offering excellent value for large-scale projects.

4.Excellent Structural Strength: With the availability of Grade 3 material, ERW piling pipes can handle heavy loads, making them suitable for demanding projects like deep foundations and heavy civil infrastructure.

5.Customizability: Pipes can be tailored in terms of diameter, wall thickness, length, and end type based on project specifications.

6.Weldability: Low phosphorus content and clean welding profiles improve the ease and durability of welding during installation.

Applications of ERW Piling Pipes

ERW piling pipes are used in a variety of construction and civil engineering applications, such as:

Foundation piling for buildings and bridges

Retaining walls and cofferdams

Marine construction, docks, and piers

Load-bearing columns in deep soil conditions

Temporary or permanent earth retention systems

Their ability to withstand axial and lateral loads while maintaining structural integrity in harsh soil or water environments makes them invaluable to modern infrastructure.