Seamless
Hot Finished Seamless
Hot-pierced and hot-rolled seamless tubes produced directly from heated billets — the primary manufacturing route for large-diameter, heavy-wall carbon and alloy steel seamless products.
Hot finished seamless tubes
OVERVIEW
Seamless from billet to pipe.
Global Seamless produces hot finished seamless (HFS) tubes by piercing heated steel billets on a rotary piercing mill and rolling to final dimensions while still at elevated temperature. This process delivers seamless pipes in larger OD ranges and heavier wall thicknesses than cold-drawn routes.
HFS tubes are the standard choice for water wall boiler tubes, large-diameter process pipe, structural hollow sections, and general mechanical tubing where tight dimensional tolerances are secondary to material integrity and cost efficiency.
✓ Rotary piercing + continuous rolling process
✓ OD range: 1.050 in (26.7 mm) – 6.625 in (168.3 mm)
✓ Wall thickness: 0.118 in (3.0 mm) – 0.591 in (15.0 mm)
✓ Carbon, alloy, and stainless grades available
✓ Normalized or as-rolled supply condition
✓ OD range: 1.050 in (26.7 mm) – 6.625 in (168.3 mm)
✓ Wall thickness: 0.118 in (3.0 mm) – 0.591 in (15.0 mm)
✓ Carbon, alloy, and stainless grades available
✓ Normalized or as-rolled supply condition
Hot finished seamless pipe
DIMENSIONAL SPECIFICATIONS
Available size range.
Cold Drawn Seamless (CDS)
| Outside Diameter (OD) | Wall Thickness (WT) | Length | Tolerance |
|---|---|---|---|
| 1.050 – 2.375 in (26.70 – 60.30 mm) | 0.118 – 0.315 in (3.00 – 8.00 mm) | up to 42 ft (12.8 m) | ±1% OD / ±12.5% WT |
| 2.375 – 4.500 in (60.30 – 114.30 mm) | 0.157 – 0.492 in (4.00 – 12.50 mm) | up to 42 ft (12.8 m) | ±1% OD / ±12.5% WT |
| 4.500 – 6.625 in (114.30 – 168.30 mm) | 0.197 – 0.591 in (5.00 – 15.00 mm) | up to 42 ft (12.8 m) | ±1% OD / ±12.5% WT |
APPLICATIONS & INDUSTRIES
Where these tubes get used.
MATERIAL GRADES
Carbon · alloy · and stainless.
CARBON STEEL
A106 · A53 · A333
Standard carbon grades for boiler, process piping, and general pressure service.
ALLOY STEEL
P11 · P22 · P91
Chrome-moly grades for elevated temperature service — produced as HFS mother tubes.
TECHNICAL ARTICLES
Latest insights on hot finished pipes.
ARTICLE
HFS vs CDS Process
When to specify HFS over CDS for your seamless tube application.
ARTICLE
Rotary Piercing Manufacturing
Step-by-step manufacturing process from billet to finished pipe.
ARTICLE
Heat Treatment for HFS
Normalizing, stress relieving, and quench-temper for HFS products.
RELATED PRODUCTS
Often paired with.
GET A QUOTE
Send your hot finished pipe spec.
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OD, WT, length, grade, heat treatment, quantity — we revert with a technical & commercial proposal.