ASTM A587 Electric-Resistance-Welded Low-Carbon Steel Pipe for Chemical Industry

ASTM A587 electric-resistance-welded low-carbon steel pipe is specifically manufactured for process piping applications in the chemical industry where reliable weld integrity, good ductility, flanging capability, and close-radius bending performance are required.

ASTM A587/A587M covers ERW low-carbon steel pipe from NPS 1/2 [DN 15] through NPS 10 [DN 250], together with specified additional sizes. The steel is aluminum-killed low-carbon steel, and the pipe is normalized after welding. Cold-drawn pipe is normalized after the final cold-drawing operation.

A key difference between ASTM A587 and general-purpose welded pipe specifications is its emphasis on forming performance. Pipe supplied to this standard is intended to withstand severe flanging operations in all covered sizes and close-radius bending through NPS 4 [DN 100].

Specifications

Main Characteristics

High Formability for Fabricated Process Lines

ASTM A587 pipe is designed for applications requiring substantially more forming than conventional straight process piping.

The material must be suitable for:

• Severe flange-forming operations across the covered size range

• Close-radius bending through NPS 4 [DN 100]

• Cold flattening without unacceptable cracking or weld failure

• Reverse flattening for assessment of weld soundness

This combination is particularly relevant where the finished process line contains formed ends, compact bends, or fabricated connections.

Controlled Low-Carbon Chemistry

ASTM A587 limits carbon to a maximum of 0.15%.

The controlled carbon level supports the ductility required for bending and flanging operations while reducing the risk of excessive hardness associated with forming and welding.

Manganese is controlled between 0.27% and 0.63%, while phosphorus and sulfur are each limited to 0.035% maximum.

Aluminum-Killed Steel

The steel is aluminum killed, with aluminum specified between 0.020% and 0.100%.

Controlled deoxidation contributes to consistent steel quality and helps provide the uniform forming characteristics required for process-pipe fabrication.

Mandatory Normalization

Pipe furnished after ERW manufacture is normalized above the upper critical transformation temperature.

For cold-drawn pipe, normalization is performed after the final cold-drawing operation.

Normalization reduces the metallurgical differences created during welding and forming and produces a more uniform microstructure across the pipe body.

Defined Mechanical Performance

The finished pipe must meet the following minimum tensile requirements:

• Tensile strength: 330 MPa minimum

• Yield strength: 205 MPa minimum

• Elongation in 50 mm: 40% minimum

The relatively high minimum elongation requirement is particularly important for flanged and bent chemical-process piping.

Our Advantages

Controlled ERW Weld Integrity

One of the main procurement concerns for chemical-process ERW piping is whether the longitudinal weld can withstand subsequent bending and flange forming without cracking.

Production control therefore focuses not only on the external appearance of the weld but also on the metallurgical and mechanical condition of the complete weld zone.

ASTM A587 inspection can include:

• Flattening testing

• Reverse-flattening testing

• Flange testing

• Eddy-current testing

• Ultrasonic testing

• Magnetic flux leakage testing

These examinations provide verification of weld continuity before the pipe enters downstream fabrication.

Forming Performance Verified Before Delivery

Chemical-equipment manufacturers frequently perform bending, end forming, and flange-forming operations after receiving the pipe.

For this reason, dimensional inspection alone is insufficient.

ASTM A587 pipe is produced specifically for severe forming applications. Normalized material condition, controlled carbon content, minimum 40% elongation, and forming tests provide a defined technical basis for evaluating whether the pipe is suitable for downstream fabrication.

For projects involving particularly small bend radii or special flange geometries, representative production samples can also be evaluated against the customer's finished-component forming requirements.

Traceable Heat, Dimensions, and Test Results

Variation between production heats can create problems during automated bending, welding, or process-equipment assembly.

Material traceability can therefore be maintained from incoming steel through ERW production, normalization, inspection, and finished-pipe identification.

Inspection documentation can include:

• Heat number

• Chemical analysis

• Tensile properties

• Outside diameter

• Wall thickness

• Straightness inspection

• Heat-treatment condition

• Nondestructive examination results

This allows purchasing and quality-control teams to verify material conformity against the purchase order before production use.

Execution Standards

Application

Chemical Dosing Skid Process-Water Transfer Pipe

A representative application is the process-water transfer pipe installed inside a chemical dosing skid.

These assemblies often require compact pipe routing, formed connections, welded branches, and accurately positioned pipe ends within limited equipment space.

ASTM A587 ERW pipe is suitable for this type of fabricated process line because its controlled low-carbon chemistry, normalized condition, minimum 40% elongation, and specified flange and flattening performance support subsequent bending and fabrication.

Actual compatibility with the transported chemical must be verified separately because ASTM A587 defines the steel pipe construction and mechanical requirements but does not establish universal corrosion resistance for all chemical media.

Chemical Composition

Mechanical Properties

Dimensional Reference

Quality Inspection

Typical ASTM A587 production inspection includes dimensional verification, material identification, mechanical testing, forming evaluation, and weld examination.

Critical control items include:

• Heat-number traceability

• Chemical composition verification

• Outside-diameter measurement

• Wall-thickness measurement

• Straightness inspection

• Tensile testing

• Flattening testing

• Reverse-flattening testing

• Flange testing

• Weld-area inspection

• Nondestructive examination

• Final visual inspection

ASTM A587 ERW low-carbon steel pipe is therefore most appropriate where a chemical-process piping project requires a combination of controlled low-carbon chemistry, normalized weld condition, high ductility, reliable forming performance, and verifiable ERW weld quality rather than only basic fluid-conveyance capability.