omplete Bolts and Nuts Program Launched for the European Market: Structural SB and Preloaded HR/HV Assemblies to EN 1504
2026/09/11
A full-range bolts and nuts program is now available to European and international buyers, spanning carbon steel property classes 4.6 to 10.9 to EN ISO 898, structural bolting assemblies to EN 15048 (SB) and EN 14399 (HR/HV preloaded systems), stainless steel fasteners to EN ISO 3506 (A2/A4), and high- and low-temperature bolting steels to EN 10269 — including X22CrMoV12-1 studs specified for P91-class flanged joints in supercritical power plants. The program completes the company's piping supply chain, allowing flanges, fittings, pipes, supports and now fasteners to be sourced under a single documentation chain with EN 10204 3.1 certification throughout.
Fasteners are the smallest components in any piping system — and the ones whose failure carries the highest consequences. Every flanged joint, pipe support anchor and structural connection in a power plant, refinery or water utility ultimately depends on the bolt holding it. Recognizing this, the company has extended its product portfolio to include a fastener program engineered to the same European standards discipline its customers already expect from its piping products.
"Our customers were buying flanges from us and then spending weeks sourcing bolts that match the flange material, the service temperature and the certification level. Now they issue one purchase order and receive one documentation package. The P91 main-steam joint is the classic case: X22CrMoV12-1 studs, matching nuts, correct lubrication procedure and full EN 10204 traceability — specified, supplied and verified as a system."
— [amy] [alloysteelseamlesspipe]
Standards Coverage Across the Full Fastener Range
- Product forms: hexagon bolts and screws to EN ISO 4014/4017, studs to EN ISO 898-1, hexagon nuts to EN ISO 4032/4034, washers to EN ISO 7089/7090 — M5 to M64
- Mechanical property classes: carbon and alloy steel classes 4.6, 5.6, 8.8, 10.9 to EN ISO 898-1/-2; matched nut classes supplied to prevent mismatched-joint failures
- Structural bolting assemblies: SB bolts, nuts and washers to EN 15048-1/-2 for general steel construction executed under EN 1090
- Preloaded assemblies: HR and HV systems to EN 14399-1/-3/-4/-6/-8 for slip-resistant, fatigue-critical connections
- Stainless fasteners: A2 and A4 property classes to EN ISO 3506-1/-2, including A4-70 and A4-80 high-strength variants
- Temperature-rated bolting: steels and nickel alloys to EN 10269 with verified elevated- and low-temperature properties
- Corrosion protection: hot-dip galvanizing to EN ISO 10684, zinc-flake coatings to ISO 10683, and PTFE topcoats for offshore-grade atmospheres
Fastener Materials and Their Application Scenarios
The program covers the full spectrum of service environments, with each material grade matched to the duty it was designed for:
|
Material |
Standard / Grade |
Key Properties |
Typical Application Scenarios |
|
Carbon steel 8.8, hot-dip galvanized |
EN ISO 898-1 / EN ISO 10684 |
800 MPa tensile; decades of atmospheric corrosion protection |
Flanged joints on carbon steel water, HVAC and utility piping; outdoor pipe racks and pipe supports; structural steelwork under EN 1090 |
|
Carbon steel 10.9 |
EN ISO 898-1 |
1000 MPa tensile; suited to high clamp loads |
High-pressure flanged joints, preloaded HR/HV connections in turbine decks and crane rails, heavy pipe support anchor points under cyclic loading |
|
Stainless A2-70 |
EN ISO 3506-1 (1.4301 base) |
General corrosion resistance, 700 MPa tensile |
Water treatment plants, food and pharmaceutical equipment, HVAC and general outdoor service with moderate chloride exposure |
|
Stainless A4-70 / A4-80 |
EN ISO 3506-1 (1.4401/1.4404 base) |
Pitting and crevice corrosion resistance; up to 800 MPa tensile |
Marine and coastal structures, chemical processing units, desalination and seawater-cooled systems, flanged joints on stainless piping |
|
42CrMo4 QT |
EN 10269 (1.7225) |
High strength retained to ~450–480 °C |
Flanged joints on 16Mo3 and 13CrMo4-5 alloy steel piping, turbine casings, compressors, hot-service pipe supports |
|
X22CrMoV12-1 |
EN 10269 (1.4923) |
Creep and relaxation resistance to ~580–600 °C |
Stud bolts for P91 / X10CrMoVNb9-1 main-steam flanges, superheater headers and HP bypass valves in supercritical and ultra-supercritical power plants — the grade that prevents stress-relaxation leakage where ordinary bolts fail |
|
34CrNiMo6 QT |
EN 10269 (1.6582) |
Impact-tested toughness down to ~ −100 °C |
Flanged joints on LNG and cryogenic piping, low-temperature P215NL/P265NL systems, Arctic structural connections |
|
Austenitic A4 / X5CrNiMo17-12-2 |
EN ISO 3506 / EN 10269 |
No ductile-to-brittle transition — inherently cryogenic-capable |
LNG tank annular piping, cold-box internal bolting, cryogenic pipe supports in chloride-containing insulation environments |
One Documentation Chain from Pipe to Bolt
The fastener program is designed to be specified together with the company's existing portfolio: forged steel flanges to EN 1092-1, butt weld fittings to EN 10253-2, alloy steel seamless pipes to EN 10216-2/-3/-4 (16Mo3, 13CrMo4-5, 10CrMo9-10, X10CrMoVNb9-1 and low-temperature grades), coated steel pipe systems, and pipe supports and hangers to EN 13480. Sourcing bolts from the same supplier as the flanges they join eliminates the most common procurement failure modes: mismatched property classes, material-grade incompatibility between fastener and flange, and documentation gaps at third-party inspection.
Quality Assurance and Compliance
- EN 10204 3.1 inspection certificates as standard — chemical composition, mechanical properties and, where applicable, impact energy at the specified low temperature; 3.2 with third-party endorsement on request
- Property class and manufacturer head marking; assembly marks for EN 14399 preloaded systems
- Lubrication and torque-tensioning procedures supplied for high-temperature and preloaded joints
- Batch-level traceability back to the forging or bar lot
- Export-grade packaging with thread protection for ocean freight
Availability
Standard carbon and stainless fasteners are available from stock or short production cycles in sizes M5 to M64; EN 10269 high-temperature and low-temperature materials are produced to order with full project documentation. Complete dimensional tables, torque guidance and material grade cross-references are available from the technical sales team.
About
[alloysteelseamlesspipe] is a manufacturer and exporter of steel piping products and components serving the European and global market, specializing in alloy steel seamless pipes to EN 10216-2/-3/-4, butt weld fittings to EN 10253-2, forged steel flanges to EN 1092-1, coated steel pipes, pipe supports and hangers to EN 13480, and industrial fasteners to EN ISO 898, EN 15048, EN 14399 and EN 10269. All products are supplied with EN 10204 inspection certificates and full traceability.
[amy]
Email: [Amy@okpipes.com]
Tel: [+8618931788358]
Website: +8618931788358
