Repsol Steel LLP is a trusted high tensile fasteners supplier for buyers across the USA, Europe, Africa, Mexico, and Oman. We supply a comprehensive range of high tensile fasteners — including Grade 8.8, 10.9, and 12.9 HT bolts, nuts, studs, and washers — engineered for high-strength bolting in structural, Oil & Gas, petrochemical, power generation, and industrial applications.
With over 25 years of combined industry experience and a proven export network, we serve EPC contractors, procurement teams, maintenance engineers, and fabrication units worldwide. Every high tensile fastener we supply complies with ASTM A325, ASTM A490, ASTM F3125, ISO 898-1, and DIN standards, with full material traceability, mechanical test reports, and documentation that meets the requirements of projects in the USA, Europe, Africa, Mexico, and Oman.
Whether you require standard Grade 8.8 HT bolts for a structural project in Europe, Grade 10.9 HT studs for a refinery in the USA, or Grade 12.9 HT fasteners for a wind tower application in Africa or Oman — Repsol Steel LLP delivers the right high tensile fastening solution, on time, with complete export documentation.
A complete high tensile fasteners portfolio covering Grade 8.8, 10.9, and 12.9 HT bolts, nuts, studs, and washers — engineered for high-strength bolting across global markets.
The standard high tensile bolts for structural and general engineering applications. Grade 8.8 bolts provide a tensile strength of 800 MPa and are widely used in steel structures, bridges, and industrial equipment.
Compliance: ISO 898-1, DIN 931, DIN 933
Tensile Strength: 800 MPa
Size Range: M6 to M100
High-strength bolts for demanding structural and mechanical applications. Grade 10.9 bolts provide a tensile strength of 1000 MPa and are used in heavy machinery, automotive, and high-load structures.
Compliance: ISO 898-1, DIN 931, DIN 933
Tensile Strength: 1000 MPa
Size Range: M6 to M100
The highest strength grade of high tensile bolts for critical applications. Grade 12.9 bolts provide a tensile strength of 1200 MPa and are used in wind towers, automotive, and precision engineering.
Compliance: ISO 898-1, DIN 912
Tensile Strength: 1200 MPa
Size Range: M6 to M56
Standard high-strength structural bolts for steel-to-steel connections in bridges, buildings, and industrial structures. ASTM A325 bolts are the preferred choice for structural bolting in the USA.
Compliance: ASTM A325, ASTM F3125
Tensile Strength: 120 ksi min
Size Range: ½" to 1½"
Heat-treated alloy steel structural bolts for high-strength applications. ASTM A490 bolts are used in critical structural connections where higher strength is required.
Compliance: ASTM A490, ASTM F3125
Tensile Strength: 150 ksi min
Size Range: ½" to 1½"
Complete high tensile bolting assemblies including Grade 8, 10, and 12 nuts, HT stud bolts, and hardened washers. Supplied as matched assemblies for reliable bolting performance.
Compliance: ISO 898-2, ASTM A563
Types: Hex Nuts, Stud Bolts, Flat Washers
Size Range: M6 to M100
High tensile fasteners are supplied in different strength grades to suit specific structural and mechanical requirements. The grade determines the tensile strength, yield strength, and application suitability of the fastener. We supply high tensile fasteners in the following grades:
All high tensile fasteners we supply are accompanied by Material Test Certificates (MTC) and mechanical test reports confirming the exact grade, tensile strength, and heat number — ensuring full traceability and compliance with international project specifications.
| Parameter | Specification |
|---|---|
| Fastener Types | HT Hex Bolts, HT Hex Nuts, HT Stud Bolts, HT Washers, Custom HT Fasteners |
| High Tensile Grades | Grade 8.8, Grade 10.9, Grade 12.9, ASTM A325, ASTM A490, ASTM F3125 |
| Size Range (Metric) | M6 to M100 standard; larger sizes available on request |
| Size Range (Imperial) | ¼" to 4" standard; larger sizes available on request |
| Length Range | Custom lengths available per project specifications |
| Thread Types | UNC, UNF, BSW, Metric (M) — per ISO 261 and ASME B1.1 |
| Coatings | Plain, Zinc Plated, Hot-Dip Galvanized, Xylan, PTFE, Dacromet, Geomet |
| Standards Compliance | ISO 898-1, ISO 898-2, ASTM A325, ASTM A490, ASTM F3125, DIN 931, DIN 933, DIN 934, DIN 912 |
| Export Documentation | Commercial Invoice, Packing List, Bill of Lading, Certificate of Origin, MTC (EN 10204 3.1) |
| Inspection Options | Third-party inspection (SGS, BV, TUV, Intertek) available on request |
Correct high tensile fastener selection is critical to ensuring a reliable structural connection and long-term operational safety. The grade, fastener type, and coating must be matched to the application requirements. Our technical team recommends evaluating four key factors before finalizing a high tensile fastener:
If you are unsure which high tensile fastener specification best suits your application, our technical team is available to review your drawings, load requirements, and project specifications — and recommend the most suitable high tensile fastening solution.
We specialize in high tensile fastener supply — offering Grade 8.8, 10.9, 12.9, ASTM A325, A490, and F3125 HT bolts, nuts, studs, and washers. All fasteners are manufactured to ISO and ASTM standards.
We supply high tensile fasteners in all major grades — Grade 8.8, 10.9, 12.9, ASTM A325, A490, and F3125 — from M6 to M100 as standard, with larger sizes and custom configurations on request.
Every high tensile fastener batch is backed by Material Test Certificates (MTC) and mechanical test reports, and can be supplied with dimensional inspection reports and third-party certification on request — ensuring full traceability for critical applications.
Non-standard sizes, grades, and high tensile fastener configurations are manufactured according to drawings, equipment specifications, and project requirements — with quick turnaround times.
We supply high tensile fasteners to clients in the USA, Europe, Africa, Mexico, and Oman — with packaging, documentation, and compliance structured for international procurement.
Our experienced technical team assists with high tensile grade selection, fastener type recommendations, and installation guidance. Post-supply support includes documentation follow-up and replacement coordination.
Repsol Steel LLP supplies high tensile fasteners to a wide range of industries across USA, Europe, Africa, Mexico, and Oman — where high-strength bolting performance is essential.
High tensile bolts supplied for steel-to-steel connections in bridges, buildings, industrial structures, and infrastructure projects.
Grade 10.9 and 12.9 high tensile fasteners supplied for wind tower structures, solar installations, and renewable energy projects.
High tensile fasteners supplied for wellhead equipment, pipeline flanges, and high-pressure process piping in upstream, midstream, and downstream operations.
High tensile fasteners supplied for boilers, steam systems, turbine connections, and high-pressure auxiliary piping in thermal and nuclear power plants.
Grade 10.9 and 12.9 high tensile fasteners supplied for automotive components, heavy machinery, and precision engineering applications.
High tensile fasteners supplied to fabrication units and EPC contractors for piping spools, skids, modular structures, and industrial assemblies.
Repsol Steel LLP is recognized as a reliable high tensile fasteners supplier for international procurement teams, EPC contractors, and maintenance projects. Our export documentation, packaging, and standard compliance are structured for smooth cross-border supply to buyers in the USA, Europe, Africa, Mexico, and Oman — ensuring your high tensile fasteners arrive on time, in specification, and ready for installation.
USA: HT fasteners for structural, Oil & Gas & power projects
Europe: HT fasteners for construction, industrial & process industries
Africa: HT fasteners for infrastructure, refinery & power projects
Mexico: HT fasteners for industrial, automotive & construction projects
Oman: HT fasteners for Oil & Gas, construction & power projects
All high tensile fasteners are supplied with material certificates, mechanical test reports, and third-party certification as required by project specifications.
High tensile fasteners are bolts, nuts, studs, and washers manufactured from medium carbon steel or alloy steel and heat-treated to achieve high tensile strength. They are used in structural connections and high-load applications where standard fasteners are not sufficient.
We supply high tensile fasteners in Grade 8.8, Grade 10.9, Grade 12.9, ASTM A325, ASTM A490, and ASTM F3125 — selected based on structural load requirements and application standards.
We supply high tensile hex bolts, hex nuts, stud bolts, washers, and custom fasteners — in various grades, sizes, and thread types per project specifications.
We supply high tensile fasteners primarily to the USA, Europe, Africa, Mexico, and Oman, serving structural, Oil & Gas, power, automotive, and industrial projects in these regions.
Yes. We offer custom sizes, grades, lengths, and high tensile fastener configurations based on drawings, equipment specifications, and project requirements — with quick turnaround times for export orders.
Send us your bolt specifications, grade requirements, or drawings. Our export team will respond within 24 hours with a tailored quotation.
Repsol Steel LLP is a leading manufacturer and stockholder of high-quality piping products, serving the Oil, Gas, Petrochemical, and Nuclear industries with reliable engineering solutions.
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