ASTM A134 / ASME SA134 EFW Carbon Steel Pipes – NPS 16″ & Over
What is ASTM A134 pipe?
ASTM A134 (ASME SA134) covers electric-fusion (arc)-welded steel pipe, straight seam or spiral seam, in sizes NPS 16 and over with wall thickness up to ¾” (19 mm). The pipe is formed from structural or pressure-vessel plate – ASTM A283, A285, A36 or A1011 – and its chemistry and strength come from the plate grade ordered. A134 adds the weld tensile, bend and hydrostatic test requirements.
ASTM A134 Pipe – Quick Facts
- Process: electric-fusion (arc) welding – straight seam (LSAW) or spiral seam (SSAW)
- Size: NPS 16″ (406 mm) and larger; wall up to ¾” (19 mm)
- Plate grades: A283 Gr C/D, A285 Gr C, A36, A1011 – stated on the order, e.g. “A134 / A283 Gr C”
- Hydrostatic test: to 60% of the plate’s minimum yield; pipe supplied untested is marked “NH”
- Typical service: water, cooling water, penstocks, low-pressure air and gas, piling and ducting
ASC LLP, Mumbai, supplies ASTM A134 straight-seam and spiral-welded pipe with EN 10204 3.1 certificates. For smaller sizes see ASTM A139 pipe; for pressure service see ASTM A671 and ASTM A672 EFW pipe.
A134 Pipe Grades – Plate Chemistry & Strength
| Plate grade | C max (%) | Mn max (%) | Tensile strength (MPa) | Yield min (MPa) |
| ASTM A283 Grade C | 0.24 | 0.90 | 380 – 515 | 205 |
| ASTM A283 Grade D | 0.27 | 0.90 | 415 – 550 | 230 |
| ASTM A285 Grade C | 0.28 | 0.90 | 380 – 515 | 205 |
| ASTM A36 (to 20 mm) | 0.25 | – | 400 – 550 | 250 |
A134 has no chemistry or tensile table of its own – the limits above come from the plate specification (phosphorus, sulphur and other elements also per the plate standard). The weld must reach at least 95% of the plate’s minimum tensile strength in production tests.
ASTM A134 vs A139 vs A671 vs A672
| Specification | Process | Sizes | Material | Typical service |
| ASTM A134 | EFW, straight or spiral | NPS 16+ , wall ≤ ¾” | Structural / PV plate (A283, A285, A36) | Water, low-pressure air & gas, piling |
| ASTM A139 | EFW, straight or spiral | NPS 4+ | Grades A – E (own chemistry & tensile) | Liquid, gas and vapour conveyance |
| ASTM A671 | EFW, with classes for RT / PWHT | NPS 16+ | Pressure-vessel plate (A516, A515…) | Atmospheric and low-temperature pressure service |
| ASTM A672 | EFW, with classes for RT / PWHT | NPS 16+ | Pressure-vessel plate | High-pressure service at moderate temperature |
A134 is the most economical of these – choose A671 or A672 when the design code requires radiography, heat treatment or a higher weld joint factor.
ASTM A134 Pipe Sizes (NPS 16″ and Over)
| NPS | OD (in) | OD (mm) | Common walls (in) |
| 16″ | 16.000 | 406.4 | 0.250 – 0.750 |
| 18″ | 18.000 | 457.2 | 0.250 – 0.750 |
| 20″ | 20.000 | 508.0 | 0.250 – 0.750 |
| 24″ | 24.000 | 609.6 | 0.250 – 0.750 |
| 30″ | 30.000 | 762.0 | 0.312 – 0.750 |
| 36″ | 36.000 | 914.4 | 0.312 – 0.750 |
| 42″ | 42.000 | 1066.8 | 0.375 – 0.750 |
| 48″ | 48.000 | 1219.2 | 0.375 – 0.750 |
Larger diameters (spiral-welded) and other OD/wall combinations are supplied to drawing, within the ¾” wall limit of A134.
A134 Testing & Dimensional Tolerances
| Test / tolerance | A134 requirement |
| Weld procedure qualification | Transverse tensile ≥ 100% of plate min tensile; two 180° face bends |
| Production weld tensile | 1 test per 3,000 ft (900 m); ≥ 95% of plate min tensile |
| Hydrostatic test | Pressure giving 60% of plate min yield (P = 2St/D), max 2,800 psi; “NH” if not tested |
| Outside circumference | ± 0.5% of nominal |
| Out-of-roundness | Max 1% difference between major and minor OD |
| Random lengths | Average ≥ 29 ft (9 m), minimum 20 ft (6 m) |
| Ends | Plain or bevelled to ASME B16.25 |
ASTM A134 / SA134 Pipe Specifications
| Item | Details |
| Product | ASTM A134 / ASME SA134 EFW carbon steel pipe |
| Plate specification | ASTM A283 Gr C/D, A285 Gr C, A36, A1011 (as ordered) |
| Seam | Straight seam (LSAW) or spiral seam (SSAW) |
| Size range | NPS 16″ and over |
| Wall thickness | Up to 0.750″ (19.05 mm) |
| Length | Single random, double random, cut lengths |
| Coating | Bare, black varnish, epoxy, coal-tar enamel, 3LPE on request |
| Marking | A134 plus plate spec and grade, size, heat number; “NH” if not hydro-tested |
| Certificate | EN 10204 3.1; third-party inspection on request |
How to Order ASTM A134 Pipe
- Specification and plate grade – e.g. “ASTM A134 / A283 Grade C”.
- Size – NPS or OD, and wall thickness.
- Seam type – straight or spiral, if the project requires one.
- Hydrostatic test – required, or “NH” accepted.
- Ends, coating and length – plain or bevelled; coating system; random or cut lengths.
For piping designed to ASME B31.3, A134 carries a weld joint quality factor of 0.80 – check that this suits the design pressure, or move to A671 / A672.
Physical Properties of Carbon Steel Plate Pipe
| Property | Value (approx.) |
| Density | 7.85 g/cm³ |
| Modulus of elasticity | ≈ 200 GPa |
| Thermal conductivity | ≈ 50 W/m·K |
| Coefficient of thermal expansion | ≈ 11.7 µm/m·°C |
Applications of ASTM A134 Pipes
| Industry | Typical uses |
| Water & utilities | Transmission mains, intake and outfall lines, cooling water |
| Hydropower | Penstocks and spillway pipework (to design approval) |
| Power & process plants | Circulating water, low-pressure air, flue and ducting |
| Construction & marine | Piling, casing, culverts and structural columns |
| Drainage | Storm water and sewer force mains |
A134 is not a boiler or high-temperature pipe – for steam and hot service use ASTM A106 Grade B or A672.
Why Buy ASTM A134 Pipes from ASC LLP?
- Correct grade on paper: certificates show the A134 spec, plate grade, heat number, chemistry and tensile results.
- Straight and spiral seam: large diameters and long lengths for water and structural projects.
- Coating options: epoxy, coal-tar enamel and 3LPE through approved coaters.
- Related pipe: LSAW pipes, A252 piling pipe and A139 pipe.
- Inspection: third-party inspection and EN 10204 3.1 certificates.
Send size, wall, plate grade, length and quantity to sales@amardeepsteel.com or contact us.
Frequently Asked Questions – ASTM A134 Pipes
What is ASTM A134 pipe?
ASTM A134 covers electric-fusion (arc)-welded steel pipe, straight or spiral seam, in sizes NPS 16 and over with wall thickness up to 3/4 inch, made from plate such as ASTM A283, A285 or A36.
What are the mechanical properties of ASTM A134 pipe?
A134 takes its strength from the plate grade. For example, A134 made from A283 Grade C plate has 380–515 MPa tensile and 205 MPa minimum yield; from A36 plate, 400–550 MPa tensile and 250 MPa minimum yield.
What is the difference between ASTM A134 and A139?
A134 is for NPS 16 and over and uses the chemistry and strength of a referenced plate specification. A139 starts at NPS 4 and has its own Grades A to E with defined chemistry and tensile properties.
Is hydrostatic testing required for A134 pipe?
A134 requires each length to be hydrostatically tested to a pressure that produces 60% of the plate minimum yield strength, up to 2,800 psi. Pipe supplied without the test must be marked NH.
Is ASME SA134 the same as ASTM A134?
Yes. ASME SA134 is the ASME Section II adoption of ASTM A134, with the same requirements, for use under ASME codes.
Global Reach
ASC LLP supplies large-diameter welded pipe, fittings and flanges to water, power and infrastructure projects worldwide, with prompt delivery and full documentation. Buyers in the USA, Europe, the Middle East and Asia rely on our ASTM A134 / ASME SA134 pipes for certified material and traceability.
Countries We Export To
UNITED STATES, EUROPE, UK, UAE, SAUDI ARABIA, OMAN, KUWAIT, JORDAN, QATAR, INDONESIA, MALAYSIA, BRAZIL, SPAIN, ITALY, FRANCE, GERMANY, BAHRAIN, SRI LANKA, AZERBAIJAN, AUSTRALIA, AUSTRIA, PHILIPPINES, TURKEY, RUSSIA, IRAN, IRAQ, CANADA, KOREA, JAPAN, YEMEN, FINLAND, ZIMBABWE, HUNGARY, PORTUGAL, VIETNAM, MOROCCO, THAILAND, SOUTH AFRICA, MEXICO, SINGAPORE, GREECE, KUWAIT, POLAND, NEW ZEALAND, SWEDEN, SWITZERLAND, BELGIUM, BHUTAN, BANGLADESH, TAIWAN, ROMANIA, CAMBODIA, KAZAKHSTAN, AFGHANISTAN.
