ASTM A193 Grade B7 Nuts Manufacturer & Exporter in India

Explore ASTM A193 Grade B7 Nuts Manufacturer & Exporter in India manufactured for demanding industrial applications with reliable strength, corrosion resistance and compliance with international standards.

-196

Min Temp

870

Max Temp

🌡

870

Suitable for continuous service up to approximately 870°C under typical operating conditions.

⚡

620

Typical tensile strength around 620 MPa depending on product form and heat treatment.

🛡

Very Good

Very Good corrosion resistance in a wide range of industrial environments.

⚖

8

Typical density is approximately 8.0 g/cm³.

Product Overview

What are ASTM A193 Grade B7 Nuts?

ASTM A193 Grade B7 nuts are high-strength, heat-treated alloy steel fasteners manufactured to pair with B7 bolts and studs for critical bolted joints in pressure vessels, piping, and flanged connections. Produced from chromium-molybdenum steel (typically AISI 4140/4142), these nuts are quenched and tempered to achieve a minimum tensile strength of 100 ksi (690 MPa) and are engineered for high-pressure, high-temperature, and corrosive service environments.

ASTM A193 Grade B7 nuts are specified for petrochemical, power generation, and refinery applications, where reliable clamping force and resistance to hydrogen embrittlement, stress corrosion cracking, and elevated temperature creep are essential. They are supplied with full traceability and mechanical test certification per ASTM A194 Grade 2H or 7, depending on the application.

Quick Specifications

MaterialAlloy Steel (AISI 4140/4142)
UNS NumberK11597
DIN Number1.7225
Material StandardASTM A193 Grade B7
Nut Standard (Metric)DIN 934 / ISO 4032
Nut Standard (Inch)ASME B18.2.2
Thread FormISO Metric / UNC / UNF
Diameter RangeM6-M100 / ¼"-4"
Tensile Strength100 ksi (690 MPa) min
Yield Strength85 ksi (585 MPa) min
Hardness24-35 HRC
? All nuts supplied with EN 10204 3.1 certification. Hardness and mechanical test reports included.

Complete the Fastener Set

Other ASTM A193 Grade B7 Fastener Products Available from RealBolt

RealBolt also manufactures the complete ASTM A193 Grade B7 fastener range — ASTM A193 Grade B7 Bolts, ASTM A193 Grade B7 Screws, ASTM A193 Grade B7 Washers, ASTM A193 Grade B7 Studs, ASTM A193 Grade B7 Threaded Rods — from certified bar stock per ASTM with full EN 10204 MTC 3.1/3.2 documentation and fast Mumbai dispatch.

Technical Data

ASTM A193 Grade B7 Nuts Dimensions, Sizes & Thread Standards

ASTM A193 Grade B7 Nuts are available in metric M6–M100 and inch ¼″–4″ as standard. Per DIN 934 (hex nut) / ISO 4032. Custom thread pitches and heavy hex per ASME B18.2.2. Metric and inch series available. All ASTM A193 Grade B7 nuts dimensions are verified against applicable DIN, ISO,

Hex Nut Dimensions - Metric (DIN 934 / ISO 4032)

Size (M)Pitch (mm)A/F (mm)Height (mm)Min L (mm)Max L (mm)
M61.0105.0510
M81.25136.5612
M101.5178.0816
M121.751910.01020
M162.02413.01326
M202.53016.01632
M243.03619.01938
M303.54624.02448
M364.05529.02958
M424.56534.03468
M485.07538.03876
M565.58545.04590
M646.09551.051102
M726.010557.057114
M806.011563.063126
M1006.014580.080160

Dimensional & Material Standards

StandardCoversThread
DIN 934Hex nutsMetric
ISO 4032Hex nutsMetric
ASME B18.2.2Hex & heavy hex nutsUNC/UNF
ASTM A194Heavy hex nuts for high-pressure/high-tempUNC/UNF
BS 1768Hex nutsBSW/BSF
Material StandardRequirement
ASTM A193 B7Alloy steel, quenched & tempered
ASTM A194 2HHeavy hex nut mechanical
EN 10204 3.1Mill test certificate
EN 10204 3.2TPI-witnessed MTC

Material Chemistry

ASTM A193 Grade B7 Chemical Composition

ASTM A193 Grade B7 Nuts are manufactured from chromium-molybdenum alloy steel with Cr (0.8–1.1%), Mo (0.15–0.65%), and vanadium additions in B16 grades, controlled per ASTM and ASME SA-193. Cr-Mo additions raise hardenability and creep rupture strength for pressure vessel service; vanadium in B16 extends the allowable service temperature to 538°C.

Chemical Composition per ASTM A193 B7

ElementComposition (%)
Carbon (C)0.37-0.49%
Manganese (Mn)0.65-1.10%
Phosphorus (P)0.035% max
Sulfur (S)0.040% max
Silicon (Si)0.15-0.35%
Chromium (Cr)0.75-1.20%
Molybdenum (Mo)0.15-0.25%
Nickel (Ni)0.25% max
Copper (Cu)0.25% max
? All heats spectro-tested and certified. Full chemical analysis provided with each batch.

Why ASTM A193 Grade B7 Alloy Composition Matters for Nuts

Cr-Mo Alloy — High Strength & Creep Resistance
Chromium and molybdenum additions provide the elevated temperature strength and resistance to softening required for pressure vessel and flange nuts in power and refinery service.
Low P & S — Prevents Embrittlement
Strict phosphorus and sulfur limits ensure ductility and toughness, reducing the risk of brittle fracture under dynamic loads or thermal cycling.
Heat Treatment — Quenched & Tempered
ASTM A193 Grade B7 nuts are always supplied quenched and tempered, ensuring uniform mechanical properties and reliable performance in critical bolted joints.

Fastener Performance

ASTM A193 Grade B7 Nuts Mechanical Properties & Torque Reference

The table below lists mechanical properties and torque reference for ASTM A193 Grade B7 Nuts per ASTM. ASTM A193 Grade B7 nuts achieve 620 MPa tensile strength, with hardness, yield, and elongation values verified by NABL-accredited testing and reported in the EN 10204 MTC.

Nut SizeRecommended Torque (Nm)Proof Load (kN)
M129062
M16220120
M20430187
M24750270
M301500420
M362600610
M424100870
M4861001200
?? Lubrication: Use molybdenum disulfide or graphite-based anti-seize for consistent preload. Torque values are for lubricated threads (K=0.15). Always verify with application engineer.

Industry Applications

ASTM A193 Grade B7 Nuts Applications — Industries & End Uses

ASTM A193 Grade B7 Nuts from RealBolt are specified across oil and gas pressure vessels, power generation, and petrochemical where very good corrosion resistance and 620 MPa tensile strength are required for reliable fastener performance. Click each industry below for detailed application examples.
ASTM A193 Grade B7 nuts are the industry standard for bolting pressure vessel manways, heat exchanger channel covers, and ASME B16.5/B16.47 flanged joints in upstream and downstream oil & gas facilities. Their high strength and temperature resistance ensure reliable sealing under cyclic pressure and thermal loads.
Used for bolting process piping, reactors, and column flanges in refineries and chemical plants, B7 nuts provide the mechanical integrity required for high-pressure, high-temperature, and hydrogen service. Compatible with A193 B7 studs and bolts for critical joints.
ASTM A193 Grade B7 nuts are specified for steam turbine casings, boiler drum flanges, and HRSG ductwork, where elevated temperature strength and resistance to creep and relaxation are essential for long-term service.
B7 nuts are used in high-pressure pump assemblies, filter housings, and pressure vessel closures in desalination and water treatment plants, offering reliable performance in both fresh and brackish water environments.

ASTM A193 Grade B7 Nuts Standards & International Certifications

ASTM A193 Grade B7 Nuts from RealBolt Engineering Industries are manufactured to internationally recognised fastener dimensional standards covering thread form, tolerances, strength grades, and quality requirements. Every batch ships with EN 10204 MTC 3.1/3.2, hardness test certificate, dimensional inspection report, and proof load test records — available on request for all orders.

Buy ASTM A193 Grade B7 Nuts from India's Leading Manufacturer — Get a Competitive Quote Today

Partner with RealBolt — India’s leading manufacturer of certified ASTM A193 Grade B7 Nuts — for competitive pricing, EN 10204 MTC 3.1/3.2 documentation, and fast Mumbai dispatch. Standard sizes are ex-stock; custom dimensions accepted with 2–3 week lead time. Request your quote today.

Answers for Buyers

ASTM A193 Grade B7 Nuts — Frequently Asked Questions

Browse expert answers to common questions about ASTM A193 Grade B7 Nuts from RealBolt — covering ASTM A193 grade, proof load, creep ratings, cryogenic L7 limits, coating options, and EN 10204 documentation. Contact our technical team directly for project-specific guidance on ASTM A193 Grade B7 nuts selection and pricing.
ASTM A193 Grade B7 nuts are available as hex nuts (DIN 934, ISO 4032), heavy hex nuts (ASME B18.2.2), and as per ASTM A194 Grade 2H or 7 for high-pressure and high-temperature service. Custom thread forms (metric, UNC, UNF, BSW) and coatings (zinc, PTFE, Xylan) are available on request.
Use molybdenum disulfide or graphite-based anti-seize (such as Molykote 1000 or Loctite LB 8008) on threads and nut faces to prevent galling and ensure consistent preload. Avoid copper-based anti-seize in hydrogen or sour service to prevent embrittlement.
Yes – ASTM A193 Grade B7 nuts are rated for continuous service up to 450°C (842°F) and are widely used in boilers, steam lines, and refinery reactors. For higher temperatures, consult for alternative grades such as B16 or stainless steel.
No MOQ for standard sizes (M12-M36) in stock – single pieces can be supplied for urgent maintenance. Custom sizes or coatings may require a 10 kg minimum. Bulk discounts apply at 50, 200, and 500 pieces.

Industrial Cities We Serve:

  • Ahmedabad
  • Aurangabad
  • Bengaluru
  • Chennai
  • Coimbatore
  • Faridabad
  • Gandhidham
  • Greater Noida
  • Gurugram
  • Hazira
  • Hosur
  • Hyderabad
  • Jamnagar
  • Jamshedpur
  • Ludhiana
  • Mumbai
  • Mundra
  • Mysuru
  • Nagpur
  • Nashik
  • Navi Mumbai
  • Noida
  • Pune
  • Rajkot
  • Sanand
  • Surat
  • Thane
  • Tiruppur
  • Vadodara
  • Visakhapatnam

Countries We Export To:

  • US
  • Canada
  • Mexico
  • Germany
  • UK
  • France
  • Italy
  • Spain
  • Netherlands
  • Belgium
  • Poland
  • Sweden
  • Norway
  • Denmark
  • Turkey
  • UAE
  • Saudi Arabia
  • Qatar
  • Oman
  • Kuwait
  • Bahrain
  • South Africa
  • Egypt
  • Nigeria
  • Australia
  • New Zealand
  • Singapore
  • Malaysia
  • Indonesia
  • Thailand
  • Vietnam
  • South Korea
  • Japan
  • Brazil