What is the difference between A193 B7 and B7M stud bolts?

Both are Cr-Mo alloy steel. B7M is heat treated to a lower maximum hardness so it can be used in sour (H2S) service under NACE MR0175 guidance, while B7 is the standard high-strength grade.

Can you supply complete flange bolting sets?

Yes. Stud bolts, heavy hex nuts and washers are supplied as sets sized to ASME B16.5 or B16.47 flange class and pipe size, and packed per flange if required.

Do your stud bolts come with heat-number traceability?

Yes. Studs and nuts can be marked with grade and heat number, and the mill test certificate is tied to that heat so your QA team can trace every batch.

Which coating is best for offshore flange bolts?

Offshore flange studs are commonly supplied with PTFE/Xylan fluoropolymer coating or hot-dip galvanizing. The right choice depends on the operator's specification and service temperature.

Can you supply low-temperature stud bolts?

Yes, ASTM A320 L7 and L7M studs with A194 grade 4 or 7 nuts are available for low-temperature and cryogenic service on request.

Industrial Fasteners Manufacturer, Wholesaler, Supplier & Exporter for Oil & Gas / Petrochemical

ASTM A193/A320 stud bolts and flange fastener sets for pressure vessels, pipelines, and refinery equipment, supplied with full material traceability.

What Oil & Gas / Petrochemical Buyers Need

ASTM A193 B7/B8/B8M stud bolts with heat-number traceability
Flange bolting sets matched to ASME B16.5 flange classes
NACE MR0175-aware material selection for sour service on request
Full documentation package for QA/QC sign-off

Common Challenges

Traceability requirements

Pressure-boundary bolting requires heat-number traceable mill certificates that many suppliers can't produce.

Long-lead alloy grades

Specialty alloy stud bolts often have long lead times from unprepared suppliers.

How We Help

Certified stud bolt sets

Stud bolts, nuts, and washers supplied as matched sets with full mill test certification.

Grade planning

Early engagement on alloy grade requirements to manage lead time for project schedules.

Standards & Grades for Oil & Gas / Petrochemical Fasteners

The specifications oil & gas / petrochemical buyers most often quote. Our partner factories manufacture to the standard, grade and finish on your drawing or purchase order.

ASTM A193 B7 / B7M / B8 / B8M

Stud bolts for high-temperature and high-pressure flange bolting; B7M is the lower-hardness version for sour service.

ASTM A194 2H / 2HM / 8 / 8M nuts

Heavy hex nuts matched to A193 studs for pressure-vessel and pipeline flanges.

ASME B16.5 / B16.47 flange bolting

Stud length and diameter sets sized to flange class and nominal pipe size.

ASTM A320 L7 / L7M

Low-temperature stud bolts for cryogenic and cold-climate service.

Materials & Coatings

Cr-Mo alloy steel (B7)

Quenched and tempered alloy steel for most refinery and pipeline flange joints.

Stainless steel 304 / 316 (B8 / B8M)

For corrosive process fluids, offshore platforms and chemical plants.

PTFE / Xylan and hot-dip galvanized coatings

Fluoropolymer and zinc coatings extend stud life in offshore and coastal atmospheres.

Countries We Supply Oil & Gas / Petrochemical Buyers In

Andorra Antigua & Barbuda Anguilla Albania Armenia American Samoa Aruba Åland Islands Azerbaijan Bosnia & Herzegovina Barbados Belgium Burkina Faso Bulgaria Burundi Bermuda Brunei Bolivia Bahamas Bhutan Botswana Belarus Central African Republic Congo - Brazzaville Côte d’Ivoire Cook Islands Cameroon Costa Rica Cuba Cape Verde Denmark Dominica Dominican Republic Ecuador Estonia Eritrea Finland Fiji Falkland Islands Micronesia Faroe Islands Gabon Grenada Georgia French Guiana Guernsey Gibraltar Greenland Gambia Guinea Guadeloupe Equatorial Guinea Greece Guatemala Guam Guinea-Bissau Guyana Hong Kong Honduras Croatia Hungary Isle of Man India Iran Iceland Jersey Jamaica Kyrgyzstan Kiribati Comoros St. Kitts & Nevis North Korea Cayman Islands Kazakhstan Laos Lebanon St. Lucia Liechtenstein Liberia Lesotho Lithuania Luxembourg Latvia Monaco Moldova Montenegro Madagascar Marshall Islands North Macedonia Myanmar (Burma)Mongolia Macao Northern Mariana Islands Martinique Mauritania Montserrat Malta Mauritius Maldives Malawi Mozambique Namibia New Caledonia Niger Nicaragua Norway Nepal Nauru Niue French Polynesia Papua New Guinea St. Pierre & Miquelon Pitcairn Islands Puerto Rico Palestinian Territories Palau Paraguay Réunion Serbia Russia Rwanda Solomon Islands Seychelles Singapore St. Helena Slovenia Slovakia Sierra Leone San Marino Senegal Suriname South Sudan São Tomé & Príncipe El Salvador Eswatini Turks & Caicos Islands Chad Tajikistan Timor-Leste Turkmenistan Tonga Trinidad & Tobago Tuvalu Tanzania Ukraine Uganda Uruguay Uzbekistan Vatican City St. Vincent & Grenadines Venezuela British Virgin Islands U.S. Virgin Islands Vanuatu Wallis & Futuna Samoa Yemen Zimbabwe Afghanistan Cambodia Cyprus Syria Taiwan Angola Benin Djibouti Libya Mali Somalia Sudan Togo Tunisia United States Canada United Kingdom Germany Netherlands France Italy Spain Poland United Arab Emirates Saudi Arabia Qatar Kuwait Oman South Africa Nigeria Kenya Egypt Turkey Vietnam Indonesia Malaysia Thailand Philippines Bangladesh Sri Lanka Brazil Mexico Chile Australia New Zealand South Korea Bahrain Jordan Iraq Morocco Algeria Ghana Ethiopia Zambia Colombia Peru Argentina Romania Czech Republic Austria Switzerland Sweden Ireland Portugal

Oil & Gas / Petrochemical Fasteners: Frequently Asked Questions

Yes, every stud bolt shipment for pressure-boundary applications includes mill test certificates traceable to heat number.

Source fasteners for your oil & gas / petrochemical operation

Send your product list, quantities, and destination port for a quote within 1-2 business days.

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