ASTM A1097 Steel Casing Pipe Carbon Electric-Fusion Welded For Mechanical

ASTM A1097 Steel Casing Pipe (Carbon) — Electric-Fusion (Arc) Welded for Mechanical Service

Material

ASTM A1097/A1097M casing pipe is a large-diameter carbon steel casing/encasement pipe manufactured by the electric-fusion (arc) welded (EFW) process with straight seam or spiral seam construction. It is built from weldable carbon/HSLA plate or coil materials allowed by the standard (e.g., ASTM A515/A516/A572/A36/A1011/A1018), selected to match the project’s strength, weldability, and service requirements.

Specifications

• Standard / Type: ASTM A1097/A1097M — Carbon steel casing pipe, EFW (arc) welded

• Size Range: NPS 10 and larger (outside diameter as specified by purchaser)

• Wall Thickness: ≥ 0.200 in (5.1 mm) (other dimensions may be supplied if compliant)

• Manufacturing: EFW (arc) welded; seams are butt joints with complete joint penetration welds (longitudinal or helical)

• Length: As specified on order, ± 1/2 in (± 13 mm) tolerance

• End Finish Options: Plain ends, beveled ends, or interlocking joint ends (A1097 supported)

  • Bevel angle: 30° +5° / -0°

• Dimensional / Geometric Controls (per A1097):

  • Weight: each length not more than 5% under theoretical weight

  • OD (circumferential): ≤ ±1% of specified OD or ≤ ±3/4 in (19 mm) circumference (whichever is smaller)

  • Roundness: ≤ 1% variation in a single plane

  • Straightness: max deviation 0.1% of pipe length

  • Thickness: ≥ 87.5% of nominal at any point; ≤ 112.5% unless purchaser approves

• Typical Quality Testing (A1097): one reduced-section weld tension test per lot of 1000 ft [300 m] (or fraction) for each diameter/thickness

• Optional (project-based): UT/RT weld inspection, dimensional mapping, third-party witnessing, protective coatings (FBE / 3LPE / epoxy / bitumen wrap), bevel protectors, ID/OD cleaning.

Key Features

• Purpose-built for casing/encasement in trenchless and underground works (boring, tunneling, open trench).

• EFW full-penetration weld design supports robust mechanical performance and reliable joint integrity.

• Large diameter capability (NPS 10+) with controlled roundness/straightness for easier jacking, alignment, and installation.

• Multiple end solutions (plain / bevel / interlocking joint) to match field welding or jacking requirements.

Our Advantages 

1) “Will the weld hold up during jacking/pullback?”
Yes. ASTM A1097 requires EFW construction with complete joint penetration welds and addresses welding procedure qualification (AWS D1.1 or purchaser-accepted code), providing a strong foundation for demanding installation loads.

2) “How do you control roundness and straightness so the pipe won’t bind?”
A1097 defines clear geometry limits for OD variation, roundness, and straightness—critical for smooth insertion and reduced friction in boring/tunneling. We manufacture and inspect to meet (or project-tighten) these tolerances.

3) “Can you supply ends that fit our site welding or interlocking needs?”
Yes—A1097 allows plain, beveled, or interlocking joint ends, including defined bevel angle requirements.

4) “What about coating damage and corrosion during HDD or aggressive soil?”
We provide coating options chosen for soil abrasiveness and installation method. Industry guidance highlights that casing/coating performance depends on coating selection and installation parameters—so we match systems (FBE/3LPE/epoxy, etc.) to the crossing conditions and handling plan.

5) “What inspection evidence do we receive?”
We support mill test documentation, lot-based weld mechanical testing as referenced in A1097, and optional NDT plans (UT/RT) when the project requires enhanced assurance for seam integrity.

Chemical Composition

Mechanical Properties

Applicable Standards

ASTM

• ASTM A1097/A1097M — Steel Casing Pipe, Carbon, Electric-Fusion (Arc)-Welded (NPS 10 and Larger)

• Related (project alternatives): ASTM A139 (EFW pipe), ASTM A252 (pipe piles/casing), ASTM A671/A672 (EFW pipe from PV plate)

EN

• EN 10219 (cold-formed welded structural hollow sections) — commonly used for structural/mechanical casing applications

• EN 10217-1 (welded steel tubes for pressure purposes) — when pressure classification is required

• EN ISO 3183 (line pipe) — when pipeline/line-pipe equivalence is requested

GOST

• GOST 20295 (welded steel pipes for trunk pipelines)

• GOST 10704 / GOST 10705 (electric-welded steel pipes)

JIS

• JIS G3452 (carbon steel pipes for ordinary piping)

• JIS G3454 (carbon steel pipes for pressure service)

• JIS G3444 (structural hollow sections)

GB

• GB/T 9711 (line pipe)

• GB/T 3091 (welded steel pipe for low pressure liquid delivery)

• GB/T 13793 (longitudinally welded steel pipe)

Application Areas

General: trenchless construction, underground utility protection, structural/mechanical sleeves, and installation support where a carrier pipe needs mechanical protection.

Typical “where it’s used” inside those fields

• Horizontal underground boring / HDD: casing/encasement to protect carrier lines and stabilize crossings

• Tunneling / pipe jacking / auger boring: casing pipe as the jacked element or protective shell

• Open trench crossings: encasement sleeves for road/rail/utility corridors

• Mechanical projects: heavy-wall sleeves, structural protection, fabricated housings where large OD and robust weld seams are required