Oil & Gas Fastener Manufacturer & Supplier: Stud Bolts, Flange Bolts and Alloy Fasteners for EPC Projects
An oil and gas project tightens thousands of flange joints, and every one of them carries a fastener specification — material, grade, hardness, coating and certificate. Yuanpai supplies oil and gas fasteners to EPC contractors and plant operators across the Americas, Europe and Asia-Pacific: stud bolts, flange bolts and alloy fasteners in carbon, stainless, duplex and nickel alloy grades, with the API and NACE compliance that project QA/QC demands.
Yuanpai — Oil & Gas Fasteners Quick Reference:
- Products: stud bolts and heavy hex nuts, flange bolts, alloy fasteners, gasket bolting sets
- Materials: ASTM A193 B7/B7M/B16/B8M, A320 L7/L7M, duplex 2205/2507, Inconel 625/718, Monel K500
- Standards: ASME B16.5 / B16.47, API 20E / 20F, NACE MR0175 / ISO 15156, EN 10204 3.1
- Applications: pipelines, refineries, wellheads, heat exchangers, pressure vessels, offshore platforms
- Sizes: M12 – M100 (1/2" – 4"), lengths per flange class and project BOM
- Certification: EN 10204 3.1, PMI, hardness, tensile and impact reports
Based on our experience supporting global EPC projects, fastener acceptance usually hinges on three practical details: correct grade selection, strict compliance with sour service limits, and complete traceability. Here is exactly what you need to specify to avoid RFQ delays and site rejections.
What Oil and Gas Projects Need from a Fastener Supplier
Three requirements dominate oil and gas fastener supply:
- Compliance — fasteners must meet the project material specification: ASTM grades, API 20E / 20F levels where specified, NACE MR0175 / ISO 15156 limits for sour service, and EN 10204 3.1 documentation
- Traceability — heat number traceability from raw bar to finished fastener, with certificates prepared per lot
- Reliability — correct grade matching (stud and nut), hardness control, and coating selection for the service environment
A supplier that covers all three reduces the risk of RFQ clarifications and site rejections.
Fastener Families for Oil and Gas Service
| Application | Fastener family | Typical grades |
|---|---|---|
| Flange bolting (ASME B16.5 / B16.47) | Stud bolts with heavy hex nuts | B7/2H, B7M/2HM, B8M/8M |
| Sour service bolting | Hardness-limited studs | B7M/2HM, duplex 2205, Inconel 625 |
| High temperature service | Alloy studs | B16, B8/B8M, Inconel 718 |
| Low temperature service | Impact-tested studs | L7/L7M |
| Wellhead and subsea | API-specified bolting | Per API 20E/20F material levels |
For each family, the grade matching rule is the same: the nut grade must meet or exceed the stud requirement, and the combination must comply with the project specification.
Sour Service and High Temperature Selection
Sour service (NACE MR0175 / ISO 15156) adds a hardness constraint: materials like B7M (≤ 22 HRC) and duplex grades are supplied within the sour service hardness limits, with heat treatment verified per heat. High temperature service adds a strength-at-temperature constraint, where grades like B16 and Inconel 718 are specified for their elevated-temperature performance.
The material selection matrix for a project depends on the service conditions, not on the flange size alone. Our Stud Bolts guide covers the grade matching details, and our Duplex & Super Duplex Fasteners and Inconel & Nickel Alloy Fasteners guides cover the alloy families.
API and NACE Compliance
- API 20E (alloy and carbon steel bolting) and API 20F (corrosion-resistant bolting) define manufacturing, quality and Product Specification Level (PSL 1/2/3) requirements for oil and gas bolting. Fasteners can be supplied to the required PSL level with the corresponding documentation. Fasteners can be supplied to the required level with the corresponding documentation.
- NACE MR0175 / ISO 15156 defines material and hardness limits for sour service. Compliance is verified through hardness testing and material documentation per heat.
State the compliance requirement in the RFQ — the certificate scope and testing follow from it.
Certification and Documentation
Project QA/QC commonly requires:
- EN 10204 3.1 certificates — chemical and mechanical properties, validated by our QA
- PMI reports — positive material identification on finished parts per lot
- Hardness, tensile and impact reports — per heat or per lot, per project scope
- Third-party inspection — witness testing and documentation review where the project requires
The certificate package is prepared per lot, with heat number traceability from raw bar to finished fastener.
How to Send an Oil and Gas Fastener RFQ
A complete RFQ reduces the clarification cycle to nearly zero. Include:
- Standard and size range (e.g. ASME B16.5, 1-1/8" x 6-1/2" studs)
- Material grades and condition (e.g. B7M with 2HM nuts, or Inconel 625 ASTM B446 annealed)
- Compliance requirements (e.g. NACE MR0175, API 20E Level 2)
- Certificate scope (e.g. 3.1 + PMI + hardness, third-party witness)
Send the BOM and our engineering team confirms the supply plan within one working day.
FAQ
Q: What fasteners are used in oil and gas pipelines?
A: Flange bolting on pipelines typically uses stud bolts with heavy hex nuts in ASTM A193/A194 grades (B7/2H for general service, B7M/2HM for sour service, B8M/8M for corrosive service), sized per the flange class and standard.
Q: What is the difference between API 20E and NACE MR0175?
A: API 20E defines manufacturing and quality requirements for oil and gas bolting, including material levels and documentation. NACE MR0175 / ISO 15156 defines material and hardness limits for sour service. Both can apply to the same fastener order; the RFQ states which are required.
Q: Do you supply certificates with the fasteners?
A: Yes. EN 10204 3.1 material certificates, PMI, hardness, tensile and impact reports per lot, with third-party inspection available where the project requires.
Q: What is the minimum order quantity?
A: Common sizes start from about 1,000 sets depending on size and grade, with project-specific quantities quoted by requirement. Send the BOM and our team will confirm the MOQ and lead time within one working day.
Get your oil and gas fastener quote within one working day — simply reply with:
- Standard & size (e.g. ASME B16.5, 1" x 5-1/2" studs)
- Grade & compliance (e.g. B7M/2HM, NACE MR0175, API 20E)
- Quantity & certificate scope (e.g. 5,000 sets with 3.1 + PMI)
Download the oil and gas fastener RFQ checklist — standard, grades, compliance and certificate requirements.
Request sample kits — evaluate material identity, hardness documentation and thread finish before ordering.
Direct WhatsApp engineering support: [+1 XXX XXX XXXX] — send the BOM or project inquiry directly to our engineering team.
Related guides: Stud Bolts · Duplex & Super Duplex Fasteners · Inconel & Nickel Alloy Fasteners · Custom Fastener Manufacturer