ASTM A194 Grade 2HM Fasteners

1. ASTM A194 Grade 2HM Fasteners – High-Strength Alloy Steel Nuts for Extreme Conditions Introduction to ASTM A194 Grade 2HM Fasteners ASTM A194 Grade 2HM Fasteners are heavy hex nuts made from alloy steel, specifically engineered for use with high-temperature or high-pressure bolting applications. These nuts are typically used with ASTM A193 Grade B7 and Grade B16 bolts, creating a reliable bolting combination for power generation, petrochemical, and pressure vessel industries. The “2HM” designation identifies these nuts as quenched and tempered alloy steel with enhanced hardness (H) and mechanical strength (M) compared to standard 2H nuts. They exhibit superior tensile strength, uniform hardness, and resistance to hydrogen embrittlement, making them ideal for extreme environments. At Dalloyed Bolts, we are trusted manufacturers, suppliers, stockists, and exporters of ASTM A194 Grade 2HM Fasteners in India, serving customers across Germany, the UK, and the UAE with premium-quality certified fasteners that meet all international standards. Types of ASTM A194 Grade 2HM Fasteners ASTM A194 Grade 2HM Fasteners are available in several configurations to match specific industrial requirements. Common variants include: •Heavy Hex Nuts (Standard) – The most widely used variant, offering uniform clamping strength and dimensional accuracy. •Lock Nuts – Used where vibration resistance is essential. •Coupling Nuts – Designed for connecting two threaded rods or bolts. •Cap Nuts and Dome Nuts – Provide aesthetic and protective coverage for exposed threads. •Flange Nuts – Used to distribute load over a larger area, ideal for machinery assembly. Each type is manufactured with precision threading, heat treatment, and surface finishing options like black oxide, zinc coating, or hot-dip galvanizing for added corrosion resistance.

2. Applications of ASTM A194 Grade 2HM Fasteners ASTM A194 Grade 2HM Fasteners are preferred in industries where temperature fluctuations, high pressure, and chemical exposure are frequent. Major application sectors include: •Petrochemical and Refinery Plants – For flanged joints and reactor assemblies. •Power Generation – Boilers, turbines, and heat-exchanger connections. •Oil & Gas Exploration – Pipeline joints and subsea pressure vessels. •Marine & Offshore Engineering – Saltwater-resistant applications. •Heavy Engineering & Process Equipment – Structural bolting and high-load assemblies. Their combination of strength and toughness ensures consistent performance even under temperatures up to 450 °C. Grades and International Standards ASTM A194 Grade 2HM Fasteners comply with multiple global standards ensuring compatibility and interchangeability: Equivalent Specification Standard Description Specification for nuts for high-pressure/high-temperature service ASTM A194ASME SA194 UNS Number K11597 Alloy-steel composition identifier DIN DIN 934 / DIN 6915 Metric heavy hex nut equivalents ISO ISO 4032 / 4033 International standard for hex nuts BS BS 1769 British standard heavy hex nuts JIS JIS B 1181 Japanese Industrial Standard for nuts All Dalloyed Bolts products are delivered with full Mill Test Certificates (MTC) and EN 10204 Type 3.1 certifications, ensuring compliance and traceability.

3. Technical Specifications Property Specification Material Quenched & Tempered Alloy Steel Hardness (Brinell)248 – 352 HB Tensile Strength ≥ 100 ksi (690 MPa) Yield Strength ≥ 92 ksi (635 MPa) Proof Load 150 ksi (1035 MPa) Temperature Range–50 °C to +450 °C Thread Series UNC, UNF, Metric Coarse (M), Metric Fine (MF) Finish Plain, Black Oxide, Zinc Plated, HDG, Phosphate These properties ensure the nuts maintain preload even in demanding mechanical or thermal environments. Dimensional & Weight Chart (Typical) Nut Size Thread Pitch Width Across Flats (mm) Thickness (mm) Approx. Weight (kg per 100 pcs) M12 1.75 mm 18 10 1.2 M16 2.00 mm 24 13 2.4 M20 2.50 mm 30 16 4.6 M24 3.00 mm 36 19 7.8 M30 3.50 mm 46 24 14.5 M36 4.00 mm 55 29 25.2 Note: Custom dimensions and tolerances available upon request.

4. Manufacturing Process Every ASTM A194 Grade 2HM Fastener manufactured by Dalloyed Bolts undergoes a strict quality-controlled process: 1.Material Selection – Alloy steel bars sourced from approved mills. 2.Hot Forging & Machining – Precise shaping under controlled heat. 3.Heat Treatment (Quenching & Tempering) – Achieves required strength and hardness. 4.Thread Rolling / Cutting – Threads formed to ASTM/ISO standards. 5.Surface Finishing – Oxidizing, galvanizing, or coating as per order. 6.Testing & Inspection – Includes NDT (UT, MPI), dimensional checks, and hardness tests. 7.Marking & Packaging – Each nut is trace-coded for full batch identification. Advantages and Benefits •High Tensile and Yield Strength ensures secure bolting under load. •Enhanced Hardness (2HM) delivers longer life than standard 2H nuts. •Excellent Corrosion and Oxidation Resistance for harsh service. •Uniform Thread Fit and Torque Performance across assemblies. •Cost-Effective due to long-term durability and fewer replacements. These features make ASTM A194 Grade 2HM Fasteners a trusted choice in high-integrity bolted connections worldwide. How to Select the Right ASTM A194 Grade 2HM Fasteners Selecting the correct fastener ensures performance and safety. Key factors to consider: •Operating Temperature and Pressure – Match to the mechanical limits of 2HM grade. •Bolting Material – Ensure compatibility with ASTM A193 bolts. •Environmental Conditions – Consider coatings for corrosion protection.

5. •Thread Form & Tolerance – Match flange or stud bolt specifications. •Certifications & Documentation – Always request MTC & traceability. Tip: When in doubt, consult with our engineering team to verify suitability before procurement. Compliance and Certifications Our ASTM A194 Grade 2HM Fasteners comply with and are supplied under: •ISO 9001:2015 – Quality Management System •PED 2014/68/EU – Pressure Equipment Directive •CE Marking – European Conformity •IBR & EIL Approved Fasteners – For Indian process industries •API 20E / 20F Compliance – For oil & gas critical service Importance of Certifications: Compliance ensures the fasteners meet mechanical and dimensional integrity requirements essential for safety-critical installations such as refineries, pipelines, and pressure vessels. ASTM A194 Grade 2HM Fasteners vs. ASTM A194 Grade 2H Fasteners Feature Grade 2H Grade 2HM Material Type Carbon / Alloy Steel Alloy Steel (Enhanced Hardness) Heat TreatmentQuenched & TemperedQuenched & Tempered (Higher Temp) Hardness Range223 – 302 HB 248 – 352 HB Strength LevelStandard Higher Applications General Service High-Pressure / High-Temp Service Recommendation: Use Grade 2HM when operating temperatures or stress levels exceed typical limits for 2H nuts.

6. FAQs About ASTM A194 Grade 2HM Fasteners Q1: What does “2HM” mean in ASTM A194 Grade 2HM? A: It indicates a hardened alloy-steel nut (H) with medium strength (M), heat-treated for higher performance. Q2: Can Grade 2HM nuts be used with stainless-steel bolts? A: Not recommended; always match with compatible alloy-steel bolts such as ASTM A193 B7. Q3: Are 2HM fasteners magnetic? A: Yes, due to the alloy-steel composition. Q4: Do you provide custom-size or metric nuts? A: Yes, Dalloyed Bolts manufactures both UNC/UNF and metric-threaded versions. Q5: What testing is performed before dispatch? A: Hardness, proof-load, impact, and non-destructive tests (UT / MPI) are carried out on every batch. Q6: Do you export to Europe and the Middle East? A: Yes, we export regularly to Germany, UK, UAE, and Saudi Arabia, meeting all region-specific standards. About Dalloyed Bolts Dalloyed Bolts is one of India’s leading manufacturers, suppliers, stockists, and exporters of high-performance industrial fasteners. With years of experience and ISO-certified manufacturing facilities, we produce a wide range of bolts, nuts, screws, washers, and studs that conform to ASTM, DIN, ISO, and BS standards. Our focus is on quality, timely delivery, and technical expertise—making us a trusted partner for major engineering, petrochemical, and energy projects worldwide. Download Technical Datasheet (PDF available on request) •Request a Quote at info@dalloyedbolts.com • Visit us at http://www.dalloyedbolts.comfor complete product details.

7. Contact Info – Mobile no - 91-7666996996 Meta Title: ASTM A194 Grade 2HM Fasteners Manufacturers | Suppliers | Exporters in India Meta Description: Certified ASTM A194 Grade 2HM Fasteners manufacturers in India — Dalloyed Bolts supplies heavy hex nuts and alloy-steel fasteners to Germany, UK, UAE & worldwide. Download datasheet or request a quote today.