ASTM A194 Grade 7 Nuts Manufacturer & Supplier

Jade Special Metals is a globally recognized manufacturer, supplier, and exporter of high-performance ASTM A194 Grade 7 Nuts. Designed for the most extreme high-pressure and high-temperature bolting applications, our A194 7 Nuts are the go-to component for maintaining joint integrity where standard nuts will fail. Manufactured to precision from premium alloy steel, our Grade 7 Heavy Hex Nuts provide certified quality and competitive pricing, making us the preferred supplier for the power generation, petrochemical, and oil & gas industries.
Quick Section Links
- What Are ASTM A194 Grade 7 Nuts?
- Types of ASTM A194 Grade 7 Nuts
- ASTM A194 Gr. 7 Nuts Specifications
- Chemical Composition of ASTM A194 GR. 7 Nuts
- Mechanical Properties of ASTM A194 GR. 7 Nuts
- ASTM A194 Gr. 7 Nuts Equivalent Grade
- ASTM A194 Gr. 7 Hex Nut Dimensions
- ASTM A194 Gr. 7 Nuts Size Chart
- ASTM A194 Gr. 7 Nuts Inventory
- Available Stock of ASTM A194 Gr. 7 Nuts
- Applications of ASTM A194 GR. 7 Nuts
What Are ASTM A194 Grade 7 Nuts?
ASTM A194 Grade 7 Nuts are heavy strength, internally threaded fasteners manufactured for use in high-pressure and high-temperature service where there is a need for more strength than the standard Grade 2H provides. While the term ASTM A194 GR.7 Fasteners is used in the market, please be aware that this specification applies only to nuts.
The main difference between Grade 7 and other common grades is the material. Grade 2H is made with carbon steel; however, A194 Gr.7 nuts are made with a higher grade alloy steel, more specifically AISI 4140/4142 type alloy steel, which is a chromium-molybdenum (chrome-moly) alloy. The combination of the alloy and the requirement for a Q&T (Quench and Temper) heat treatment, provides the A194 7 Nuts with strength and hardness at higher temperatures. Due to the higher loads, these ASTM A194 gr 7 nuts would almost exclusively be supplied as heavy hex nuts for larger bearing surface and higher stripping resistance.
Types of ASTM A194 Grade 7 Nuts

ASTM A194 Gr 7 Heavy Hex Nuts

ASTM A194 Gr 7 Hex Nuts

ASTM A194 Gr 7 Jam Nuts

ASTM A194 Grade 7 Washer

ASTM A194 Gr 7 Panel Nuts

ASTM A194 Gr 7 Wing Nuts

ASTM A194 Gr 7 Lock Nut

ASTM A194 Gr 7 T Nuts

ASTM A194 Gr 7 Square Nuts

ASTM A194 Gr 7 Nylon Insert Nuts

ASTM A194 Gr 7 Nyloc Nuts
ASTM A194 GR. 7 Nuts Specifications
Grade | ASTM A194 Grade 8 |
Standards | DIN, ISO, JIS, GB, IS, BS, ASTM |
Dimension | ASME B18.2.1, B18.3 |
Size | M02 to M160 |
Types | Hexagon Nuts, Self Locking Nut, Square Nuts, Hexagon Coupling Nuts, Hexagon Castle Nuts, Hexagon Domed Cap Nuts, Hexagon Thin Nuts, Hexagon Thin Nuts etc. |
Chemical Composition of ASTM A194 GR. 7 Nuts
Element | Percentage (%) |
Carbon (C) | 0.37 – 0.49% |
Manganese (Mn) | 0.65 – 1.10% |
Silicon (Si) | 0.15 – 0.35% |
Phosphorus (P) | 0.035% |
Sulfur (S) | 0.04% |
Chromium (Cr) | 0.75 – 1.2% |
Nickel (Ni) | — |
Molybdenum (Mo) | 0.15 – 0.25% |
Mechanical Properties of ASTM A194 GR. 7 Nuts
Thread Series |
Nut Size Range |
Proof Load Stress |
Hardness (Rockwell) |
Hardness (Brinell) |
UNC |
1/4″ to 4″ |
150,000 psi |
C24 to C38 |
248 to 352 HBW |
8-UN |
Over 1″ |
150,000 psi |
C24 to C38 |
248 to 352 HBW |
ASTM A194 GR. 7 Nuts Equivalent Grade
Standards | Designation | UNS |
ASTM | A194 | Grade : 7 , 410 Stainless Steel, Quenched and Tempered. | S41000 |
ASTM A194 GR. 7 Hex Nut Dimensions
Nominal Size or Basic Major Thread Diameter | F | G | H | ||||||
Width Across Flats |
Width Across Corners |
Thickness | |||||||
Basic | Max | Min | Max | Min | Basic | Max | Min | ||
1/4 | .2500 | 8C/16 | .438C | .428C | .505 | .48C8C | 8C/32 | .226 | .212 |
5/16 | .3125 | 1/2 | .500 | .48C9 | .58C8C | .558C | 18C/64 | .28C3 | .258C |
3/8C | .38C50 | 9/16 | .562 | .551 | .650 | .628C | 21/64 | .338C | .48C9 |
8C/16 | .438C5 | 11/16 | .68C8C | .68C5 | .8C94 | .8C68C | 3/8C | .38C5 | .365 |
1/2 | .5000 | 3/4 | .8C50 | .8C36 | .8C66 | .8C40 | 8C/16 | .448C | .428C |
9/16 | .5625 | 8C/8C | .8C8C5 | .8C61 | 1.010 | .98C2 | 31/64 | .496 | .48C3 |
5/8C | .6250 | 15/16 | .938C | .922 | 1.08C3 | 1.051 | 35/64 | .559 | .535 |
3/4 | .8C500 | 1-1/8C | 1.125 | 1.08C8C | 1.299 | 1.240 | 41/64 | .665 | .618C |
8C/8C | .8C8C50 | 1-5/16 | 1.312 | 1.269 | 1.516 | 1.448C | 3/4 | .8C8C6 | .8C24 |
1 | 1.0000 | 1-1/2 | 1.500 | 1.450 | 1.8C32 | 1.653 | 55/64 | .8C8C8C | .8C31 |
1-1/8C | 1.1250 | 1-11/16 | 1.68C8C | 1.631 | 1.949 | 1.8C59 | 31/32 | .999 | .939 |
1-3/8C | 1.38C50 | 2-1/16 | 2.062 | 1.994 | 2.38C2 | 2.28C3 | 1-11/64 | 1.206 | 1.138C |
1-1/2 | 1.500 | 2-1/4 | 2.250 | 2.18C5 | 2.598C | 2.48C0 | 1-9/32 | 1.ASTM A194 GR. 8C | 1.245 |
1-5/8C | 1.6250 | 2-8C/16 | 2.438C | 2.356 | 2.8C15 | 2.68C6 | 1-25/64 | 1.429 | 1.353 |
1-3/4 | 1.8C500 | 2-5/8C | 2.625 | 2.538C | 3.031 | 2.8C93 | 1-1/2 | 1.540 | 1.460 |
2 | 2.0000 | 3 | 3.000 | 2.900 | 3.464 | 3.306 | 1-23/32 | 1.8C63 | 1.68C5 |
2-1/4 | 2.2500 | 3-3/8C | 3.38C5 | 3.263 | 3.8C98C | 3.8C19 | 1-15/16 | 1.98C6 | 1.8C90 |
2-1/2 | 2.5000 | 3-3/4 | 3.8C50 | 3.625 | 4.330 | 4.133 | 2-5/32 | 2.209 | 2.105 |
2-3/4 | 2.8C500 | 4-1/8C | 4.125 | 3.98C8C | 4.8C63 | 4.546 | 2-3/8C | 2.431 | 2.319 |
“Contact Jade Special Metals today with your requirement for ASTM A194 GR. 7 Nuts. We assure you of the best quote.
ASTM A194 GR. 8 Nuts Size Chart
Nuts Size (mm) |
Diameter* (mm) |
Height (mm) |
||
---|---|---|---|---|
Hex Nuts | Jam Nuts | Nylock Nuts | ||
2 | 4 | 1.6 | 1.2 | – |
2.5 | 5 | 2 | 1.6 | – |
3 | 5.5 | 2.4 | 1.8 | 4 |
4 | 7 | 3.2 | 2.2 | 5 |
5 | 8 | 4 | 2.7 | 5 |
6 | 10 | 5 | 3.2 | 6 |
7 | 11 | 5.5 | 3.5 | – |
8 | 13 | 6.5 | 4 | 8 |
10 | 17 | 8 | 5 | 10 |
12 | 19 | 10 | 6 | 12 |
14 | 22 | 11 | 7 | 14 |
16 | 24 | 13 | 8 | 16 |
18 | 27 | 15 | 9 | 18.5 |
20 | 30 | 16 | 10 | 20 |
* This is the diameter across the flats. It is also the size of wrench to use. |
Available Stock of ASTM A194 GR. 7 Nuts
- ASTM A194 Gr. 7 | ASME B18.2.1 High Nuts
- ASTM A194 Gr. 7 Self Locking Nuts
- ASTM A194 Gr. 7 Nut
- ASME B18.2.1 ASTM A194 8 Nuts
- ASTM A194 Gr. 7 Wing Nut
- ASTM A194 Gr. 7 Hexagone Nuts
- ASTM A194 Gr. 7 Panel Nut
- ASTM A194 Gr. 7 Serrated Flange Nut
- ASTM A194 Gr. 7 Dome Nuts
- ASTM A194 Gr. 7 Serrated Flange Nuts
- ASTM A194 Gr. 7 Hex Nut
- ASTM A194 Gr. 7 Spring T Nuts
- ASTM A194 Gr. 7 Hex Nuts
- ASTM A194 Gr. 7 Heavy Hex Nuts
- ASTM A194 Gr. 7 Hexagon Nuts
- ASTM A194 Gr. 7 2 Way Lock Nuts
- ASTM A194 Gr. 7 Hex Nuts
- ASTM A194 Gr. 7 Coupler Nuts
- ASTM A194 Gr. 7 2 Way Lock Nut
- ASTM A194 Gr. 7 Structural Nuts
- ASTM A194 Gr. 7 Square Nuts
- ASTM A194 Gr. 7 Flex Lock Nut
- ASTM A194 Gr. 7 Slotted Nut
- ASME SA194 Gr. 7 B18.3 Nylon Insert Nut
Applications of ASTM A194 GR. 7 Nuts
Oil & Gas/Petrochemical: Essential in pipelines, drilling, processing, reactors, and piping in extreme pressure and temperature.
Power Generation: Used to secure flanged connections in boilers, steam lines, and turbines in thermal and nuclear power plants.
Low-Temperature/Cryogenic Service: Capable of outstanding toughness in extreme cold environments, often used with A320 L7 studs.
Industrial Equipment: Used in heat exchangers, condensers, boilers, valves, fittings, and pressure vessels applications.
Chemical/Biochemical: Suitable for applications where corrosive media are present due to material characteristics.

Why Choose Jade Special Metals for ASTM A194 GR.7 Fasteners?
- Specialist Manufacturer: We are an experienced manufacturer with complete control of the critical heat treatment of the alloy steel, to guarantee consistency in hardness and strength of every A194 grade 7 nut we produce.
- Certification of Quality: For every order, we provide a Mill Test Certificate (MTC), which will give you indisputable verifiable evidence of quality and complete traceability for your records.
- Extensive inventory for your critical needs: We keep large inventories of grade 7 heavy hex nuts in a full range of sizes, for rapid delivery when you need immediate delivery for your project or MRO.
- Competitive Shipping Price: Our efficient manufacturing and direct to market selling price allow us to guarantee you a highly competitive unit price without sacrificing the certified quality that your critical application requires.
- Global Export Expertise: We have a robust logistics network and proven experience exporting ASME SA 194 Gr 7 Hex Nut products to clients worldwide, handling all documentation for a seamless experience.
Get a Competitive Price for ASTM A194 Grade 7 Fasteners
Partner with the experts for your critical fastening needs. Contact Jade Special Metals today for a prompt and competitive quote on your ASTM A194 Grade 7 Nuts requirements. Our team is ready to assist you with technical specifications and logistics to ensure your project’s success.