ASTM A194 Grade 8 Nuts & Fasteners Manufacturer & Supplier

Jade Special Metals is a premier manufacturer, supplier, and exporter of high-performance ASTM A194 Grade 8 Nuts. As the standard for stainless steel bolting in high-temperature and corrosive service, our A194 8 Nuts are precision-manufactured from Type 304 Stainless Steel to ensure superior reliability. We maintain an extensive inventory of A194 Gr.8 Heavy Hex Nuts, providing certified quality and a competitive price to clients in the petrochemical, chemical processing, and power generation industries.
Quick Section Links
- What Are ASTM A194 Grade 8 Nuts?
- Types of ASTM A194 Grade 8 Nuts
- ASTM A194 GR. 8 Nuts Specifications
- Chemical Composition of ASTM A194 GR. 8 Nuts
- Mechanical Properties of ASTM A194 GR. 8 Nuts
- ASTM A194 GR. 8 Nuts Equivalent Grade
- ASTM A194 GR. 8 Hex Nut Dimensions
- ASTM A194 GR. 8 Nuts Size Chart
- ASTM A194 GR. 8 Nuts Inventory
- Available Stock of ASTM A194 GR. 8 Nuts
- Applications of ASTM A194 GR. 8 Nuts
What Are ASTM A194 Grade 8 Nuts?
ASTM A194 Grade 8 Nuts are internally threaded fasteners for high temperature and corrosive service applications. ASTM A194 / ASME SA194 standards govern Grade 8 nuts and is one of the most used stainless steel grades in the referenced specifications. The general category of the material will be ASTM A194 GR.8 Fasteners, but it is important to note that the A194 standard exclusively covers nuts.
The A194 Gr 8 Nuts are classified by their material; they are Type 304 Stainless Steel (UNS S30400). This chromium-nickel austenitic stainless steel has good corrosion resistance to many environments and strength performance at high temperatures.
To achieve the best corrosion resistance and mechanical properties, all SA194 gr 8 nuts must be carbide solution treated (solution annealed). The heat treatment dissolves chromium carbides that form during the manufacturing process and is essential for preventing intergranular corrosion. They are typically delivered in a heavy hex, giving more bearing surface of the nut, and in a strain-hardened condition to achieve the proof load strength for the nut.
Types of ASTM A194 Grade 8 Nuts

ASTM A194 GR.8 Hex Nuts

ASTM A194 GR.8 Jam Nuts

ASTM A194 GR.8 Heavy Hex Nuts

ASTM A194 GR.8 Coupling Nuts

ASTM A194 GR.8 Lock Nut

ASTM A194 GR.8 Nylon Insert Nut

ASTM A194 GR.8 Self Locking Nuts
ASTM A194 GR. 8 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. 8 Nuts
Percentage | % |
C. | 0.08M % |
Mn. | 2.00 % |
Si. | 1.00 % |
P. | 0.05 %. |
S. | 0.03 % |
Cr. | 18.0-20.0 % |
Ni. | 8.0-11.0 |
Mo. | — |
Mechanical Properties of ASTM A194 GR. 8 Nuts
Thread Series |
Nut Size Range |
Proof Load Stress |
Hardness (Rockwell) |
Hardness (Brinell) |
All |
1/4″ to 1-1/2″ |
80,000 psi |
B80 max |
150 HBW max |
ASTM A194 GR. 8 Nuts Equivalent Grade
Standards | Designation | UNS |
ASTM | A194 | Grade : 8 , AISI 304 Stainless Steel Hex Nuts. | S30400 |
ASTM A194 GR. 8 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 |
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. |
“Contact Jade Special Metals today with your requirement for ASTM A194 GR. 8 Nuts. We assure you of the best quote.
Available Stock of ASTM A194 GR. 8 Nuts
- ASTM A194 GR. 8 Panel Nut
- ASTM A194 GR. 8 Nut
- ASTM A194 GR. 8 Self Locking Nuts
- ASTM A194 GR. 8 Hex Nut
- ASTM A194 GR. 8 Spring T Nuts
- ASTM A194 8 UNS S30400 Dome Nuts
- ASTM A194 GR. 8 | ASME B18.2.1 High Nuts
- ASME B18.2.1 ASTM A194 8 Nuts
- ASTM A194 GR. 8 Wing Nut
- ASTM A194 8 UNS S30400 Serrated Flange Nuts
- ASTM A194 GR. 8 Hexagone Nuts
- ASTM A194 GR. 8 Serrated Flange Nut
- ASTM A194 GR. 8 Hex Nuts
- ASTM A194 GR. 8 Heavy Hex Nuts
- ASTM A194 GR. 8 Flex Lock Nut
- ASTM A194 GR. 8 Structural Nuts
- ASTM A194 8 UNS S30400 Hex Nuts
- ASME SA194 Gr. 8 B18.3 Nylon Insert Nut
- ASTM A194 GR. 8 Square Nuts
- ASTM A194 GR. 8 2 Way Lock Nut
- ASTM A194 8 UNS S30400 Coupler Nuts
- ASTM A194 8 UNS S30400 Slotted Nut
- ASTM A194 GR. 8 Hexagon Nuts
- ASTM A194 GR. 8 2 Way Lock Nuts
Applications of ASTM A194 GR. 8 Nuts
Petrochemical & Refineries: Process piping, reactors, and pressure vessels handling corrosive fluids.
Chemical Processing: Equipment and pipelines where resistance to various acids and chemicals is required.
Power Generation: Used in boiler systems, heat exchangers, etc. where they encounter high temperatures and corrosive flue gases.
Food & Beverage Industry: For sanitary applications which require resistance to organic acids and cleaning solutions.

Why Choose Jade Special Metals for ASTM A194 GR.8 Fasteners?
- Specialist Manufacturer: With years of manufacturing ASTM A194 GR.8 Fasteners, we control the critical solution annealing process to ensure consistency of quality.
- Certified Quality: Each order ships with a Mill Test Certificate (MTC) to guarantee compliance with all chemical and mechanical properties as required by the ASTM A194 standard.
- Extensive Inventory: We stock a lot of A194 Gr.8 Heavy Hex Nuts in a wide range of sizes, ensuring fast delivery and reduced lead times for your projects.
- Competitive Price: Our efficient manufacturing and direct-to-market approach as a supplier and manufacturer ensure you receive a highly competitive price.
- Global Exporter: We are a proven global exporter, with a solid logistics network, and deal with all documentation to ensure a hassle free experience.
Get a Competitive Price for ASTM A194 GR.8 Fasteners
Partner with a specialist manufacturer for your critical fastening needs. As a direct supplier, Jade Special Metals offers a significant advantage in sourcing your ASTM A194 Grade 8 Nuts. We provide factory-direct pricing, eliminating unnecessary markups while maintaining the strictest quality control.
Our team of stainless steel experts is ready to assist you with material selection and technical specifications. Contact us today for a prompt and competitive quote on your A194 8 Nuts requirements.