Stainless Steel Hex Bolts Manufacturer in India
Unifit fastener is a leading manufacturer and supplier of high quality stainless steel hex bolts, which is designed to provide strength, reliability, and extended durability in all its applications in industries. Our hex bolts have a six-sided head and are precision threaded with a six-sided head and provide significant security in the structural, mechanical and high-load applications.
We provide a diverse selection of stainless steel grades are delivering exceptional corrosion resistance, heat resistance, and mechanical strength for diverse operating conditions. Among these, SS 304/304H/304L Hex Bolts are still very popular due to their flexibility, and Hex Bolts of SS 316/316L and 317/317L offer better protection against chemicals and chlorides. Grades such as 310/310S and 321 are the best grades to use in high temperature conditions and 347/347H has excellent stability in a harsh service condition.
We manufacture both fully threaded and partially threaded hex bolts, which are in conformity with significant international standards like DIN 931, DIN 933, ISBN 4014, ASTM, and ASME, and fit perfectly and can be used anywhere. Every bolt is manufactured with high quality standards, providing high tensile quality, torque quality and wear resistance.
Our Stainless Steel Hex Bolts are popular in constructions, marine, petrochemical, automotive, fabrication and heavy engineering where regular performance is required.
We supply high quality stainless steel hex bolts with zero-defects quality at fair prices and with high quality, which means that they are dependable suppliers of high quality stainless steel hi-tech hex bolts that are used in critical industrial applications.
Request QuoteTable of Contents
- What are Stainless Steel Hex Bolts?
- Specification of Stainless Steel Hex Bolts
- Send Your Enquiry
- Stainless Steel Hex Bolts Types
- Equivalents of Hex Head Bolt Stainless Steel
- Chemical Composition of M8 Stainless Steel Hex Bolts
- Mechanical Properties of Stainless Steel Hex Bolts
- Stainless Steel Hex Bolts Physical Properties
- Torque Chart of Stainless Steel Hex Bolts
- SS Hex Bolt Size Chart
- Challenges of Using Stainless Steel Hex Bolts in Acidic Environments
- Applications of Stainless Steel Hex Bolts
- FAQs about Stainless Steel Hex Bolts
What are Stainless Steel Hex Bolts?
A stainless steel hex bolt is a strong fastener with a six sided head and fully or partially threaded shank and is made out of a corrosion-resistant stainless steel. It is also very popular in places where moisture, chemicals, and/or outdoor operations may lead to rusting. This is a bolt that is designed to be tightened with the help of a wrench or socket tool and can hold parts together when it is combined with a nut or inserted into a pre-threaded hole. Well-used material choices are SS 304 and SS 316, with the latter providing better performance in the presence of chloride or highly corrosive environments
Grades of Stainless Steel Hex Bolts
Specification of Stainless Steel Hex Bolts
| Category | Details |
|---|---|
| Product Name | Stainless Steel Hex Bolts |
| Available Standards | DIN 931, ISO 4017, DIN Series, GB 5783, ANSI, ASTM, EN, JIS |
| ISO Standards Covered | ISO 4032, ISO 4033, ISO 4017, ISO 7380, JIS equivalents |
| DIN Standards Offered | DIN 931, DIN 933, DIN 912, DIN 934, DIN 6923, DIN 603 |
| Surface Finish Options | Passivated / Plain |
| Hex Bolt Size Range | M2 – M100 |
| Bolt Diameter Range | M3 – M60 |
| Bolt Length Range | 6 mm – 500 mm |
| Head Style Variants | Hex, Square, Hex Flange, Round, Flat, T-Head, Triangular |
| Neck Style Options | Square, Hex, Oval, Triangular, Knurled |
| Drive Type Options | Slotted, Phillips, Torx, Hex Socket, Square Slot |
| Dimensional Standard | ASME B18.6.3 (screws ≤6 inches are fully threaded) |
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Stainless Steel Hex Bolts Types
Stainless Steel Hexagon Socket Bolts
Stainless Hex Cap Bolts
SS Hex Flange Bolts
Stainless Steel Hex Lag Bolts
Stainless Hex Drive Bolts
SS Hex Key Bolts
Stainless Heavy Hex Bolt
Stainless Steel Metric Hex Bolts
Equivalents of Hex Head Bolt Stainless Steel
| STANDARD | UNS | WERKSTOFF NR. | JIS | EN | AFNOR | BS | GOST |
|---|---|---|---|---|---|---|---|
| SS 304 | S30400 | 1.4301 | SUS 304 | X5CrNi18-10 | Z7CN18-09 | 304S31 | 08Х18Н10 |
| SS 304L | S30403 | 1.4306 / 1.4307 | SUS 304L | X2CrNi18-9 / X2CrNi19-11 | Z3CN18-10 | 3304S11 | 03Х18Н11 |
| SS 304H | S30409 | 1.4301 | – | – | – | – | – |
| SS 310 | S31000 | 1.4841 | SUS 310 | X15CrNi25-20 | – | 310S24 | 20Ch25N20S2 |
| SS 310S | S31008 | 1.4845 | SUS 310S | X8CrNi25-21 | – | 310S16 | 20Ch23N18 |
| SS 316 | S31600 | 1.4401 / 1.4436 | SUS 316 | X5CrNiMo17-12-2 / X3CrNiMo17-13-3 | Z7CND17-11-02 | 316S31 / 316S33 | – |
| SS 316L | S31603 | 1.4404 / 1.4435 | SUS 316L | X2CrNiMo17-12-2 / X2CrNiMo18-14-3 | Z3CND17-11-02 / Z3CND18-14-03 | 316S11 / 316S13 | 03Ch17N14M3 / 03Ch17N14M2 |
| SS 316Ti | S31635 | 1.4571 | SUS 316Ti | X6CrNiMoTi17-12-2 | Z6CNDT17-123 | 320S31 | 08Ch17N13M2T |
| SS 317 | S31700 | 1.4449 | SUS 317 | – | – | – | – |
| SS 317L | S31703 | 1.4438 | SUS 317L | X2CrNiMo18-15-4 | – | – | – |
| SS 321 | S32100 | 1.4541 | SUS 321 | X6CrNiTi18-10 | – | – | – |
| SS 321H | S32109 | 1.4878 | SUS 321H | X12CrNiTi18-9 | – | – | – |
| SS 347 | S34700 | 1.4550 | SUS 347 | X6CrNiNb18-10 | – | – | 08Ch18N12B |
| SS 410 | S41000 | 1.4006 | SUS 410 | X12Cr13 | – | 410S21 | – |
| SS 446 | S44600 | 1.4762 | – | – | – | – | – |
| SS 904L | N08904 | 1.4539 | SUS 904L | X1NiCrMoCu25-20-5 | Z2 NCDU 25-20 | 904S13 | STS 317J5 |
Chemical Composition of M8 Stainless Steel Hex Bolts
| Grades | Cr (%) | S (%) | Ni (%) | Mn (%) | Mo (%) | P (%) | C (%) | Si (%) |
|---|---|---|---|---|---|---|---|---|
| SS 304 | 18.00–20.00 | 0.03 max | 8.00–10.50 | 2.00 max | — | 0.045 max | 0.08 max | 0.75 max |
| SS 304L | 18.00–20.00 | 0.03 max | 8.00–12.00 | 2.00 max | — | 0.045 max | 0.03 max | 0.75 max |
| SS 304H | 18.00–20.00 | 0.03 max | 8.00–12.00 | 2.00 max | — | 0.045 max | 0.04–0.10 | 1.00 max |
| SS 310 | 24.00–26.00 | 0.03 max | 19.00–22.00 | 2.00 max | — | 0.045 max | 0.25 max | 1.50 max |
| SS 310S | 24.00–26.00 | 0.03 max | 19.00–22.00 | 2.00 max | — | 0.045 max | 0.08 max | 1.50 max |
| SS 316 | 16.00–18.00 | 0.03 max | 10.00–14.00 | 2.00 max | 2.00–3.00 | 0.045 max | 0.08 max | 0.75 max |
| SS 316L | 16.00–18.00 | 0.03 max | 10.00–14.00 | 2.00 max | 2.00–3.00 | 0.045 max | 0.03 max | 0.75 max |
| SS 316Ti | 16.00–18.00 | 0.03 max | 10.00–14.00 | 2.00 max | 2.00–3.00 | 0.045 max | 0.08 max | 0.75 max |
| SS 317 | 18.00–20.00 | 0.03 max | 11.00–15.00 | 2.00 max | 3.00–4.00 | 0.045 max | 0.10 max | 1.00 max |
| SS 317L | 18.00–20.00 | 0.03 max | 11.00–15.00 | 2.00 max | 3.00–4.00 | 0.045 max | 0.03 max | 1.00 max |
| SS 321 | 17.00–19.00 | 0.03 max | 9.00–12.00 | 2.00 max | — | 0.045 max | 0.08 max | 1.00 max |
| SS 321H | 17.00–19.00 | 0.03 max | 9.00–12.00 | 2.00 max | — | 0.045 max | 0.04–0.10 | 1.00 max |
| SS 347 | 17.00–19.00 | 0.03 max | 9.00–13.00 | 2.00 max | — | 0.045 max | 0.08 max | 1.00 max |
| SS 410 | 11.50–13.50 | 0.03 max | — | 1.00 max | — | 0.04 max | 0.15 max | 1.00 max |
| SS 446 | 23.00–28.00 | 0.03 max | — | 1.50 max | — | 0.04 max | 0.20 max | 1.00 max |
| SS 904L | 19.00–23.00 | 0.03 max | 24.00–26.00 | 2.00 max | 4.00–5.00 | 0.045 max | 0.02 max | 1.00 max |
Mechanical Properties of Stainless Steel Hex Bolts
| Stainless Steel Grade | Tensile Strength (MPa) | Yield Strength (MPa) | Hardness (HRB) | Poisson’s Ratio | Elastic Modulus (GPa) | Elongation (%) |
|---|---|---|---|---|---|---|
| 304 | 520–720 | ~205 | 85–95 | 0.29 | 193 | 40–50 |
| 304L | 520–720 | ~205 | 85–95 | 0.29 | 193 | 40–50 |
| 304H | 520–720 | ~205 | 85–95 | 0.29 | 193 | 40–50 |
| 310 | 515–740 | 205–275 | 90–105 | 0.29 | 193 | 40–50 |
| 310S | 515–740 | 205–275 | 90–105 | 0.29 | 193 | 40–50 |
| 316 | 520–720 | ~205 | 85–95 | 0.29 | 193 | 40–50 |
| 316L | 520–720 | ~205 | 85–95 | 0.29 | 193 | 40–50 |
| 316Ti | 520–720 | ~205 | 85–95 | 0.29 | 193 | 40–50 |
| 317 | 520–730 | ~205 | 85–95 | 0.29 | 193 | 40–50 |
| 317L | 520–730 | ~205 | 85–95 | 0.29 | 193 | 40–50 |
| 321 | 520–720 | ~205 | 85–95 | 0.29 | 193 | 40–50 |
| 321H | 520–720 | ~205 | 85–95 | 0.29 | 193 | 40–50 |
| 347 | 520–720 | ~205 | 85–95 | 0.29 | 193 | 40–50 |
| 410 | 520–720 | ~205 | 85–95 | 0.28 | 190 | 35–45 |
| 446 | 520–720 | ~205 | 85–95 | 0.28 | 190 | 40–50 |
| 904L | 520–720 | ~205 | 85–95 | 0.29 | 193 | 40–50 |
Stainless Steel Hex Bolts Physical Properties
| Grade | Density (g/cm³) | Melting Point (°C) | Electrical Resistivity (µΩ·cm) | Coefficient of Thermal Expansion (μm/m·°C) | Thermal Conductivity (W/m·K) |
|---|---|---|---|---|---|
| SS 304 | 7.93 | 1400–1450 | 72.3 | 16.0 | 16.2 |
| SS 304L | 7.93 | 1400–1450 | 72.3 | 16.0 | 16.2 |
| SS 304H | 7.93 | 1400–1450 | 72.3 | 16.0 | 16.2 |
| SS 310 | 7.90 | 1400–1450 | 72.0 | 17.0 | 14.0 |
| SS 310S | 7.90 | 1400–1450 | 72.0 | 17.0 | 14.0 |
| SS 316 | 7.98 | 1375–1400 | 74.0 | 16.5 | 16.3 |
| SS 316L | 7.98 | 1375–1400 | 74.0 | 16.5 | 16.3 |
| SS 316Ti | 7.98 | 1375–1400 | 74.0 | 16.5 | 16.3 |
| SS 317 | 7.95 | 1375–1400 | 74.5 | 16.5 | 16.3 |
| SS 317L | 7.95 | 1375–1400 | 74.5 | 16.5 | 16.3 |
| SS 321 | 7.93 | 1400–1450 | 74.0 | 16.0 | 16.2 |
| SS 321H | 7.93 | 1400–1450 | 74.0 | 16.0 | 16.2 |
| SS 347 | 7.93 | 1400–1450 | 74.0 | 16.0 | 16.2 |
| SS 410 | 7.75 | 1480–1530 | 78.0 | 11.5 | 30.0 |
| SS 446 | 7.80 | 1400–1450 | 76.0 | 11.5 | 30.0 |
| SS 904L | 8.00 | 1350–1400 | 70.0 | 16.0 | 15.0 |
Torque Chart of Stainless Steel Hex Bolts
| Size Range | 18-8 Stainless Steel Hex Bolts (in-lbs) | 2024-T4 Aluminum Hex Bolts (in-lbs) | Silicon Bronze Hex Bolts (in-lbs) | Brass Hex Bolts (in-lbs) | Monel Hex Bolts (in-lbs) |
|---|---|---|---|---|---|
| 4-40 | 5.2 | 2.9 | 4.8 | 4.3 | 5.3 |
| 4-48 | 6.6 | 3.6 | 6.1 | 5.4 | 6.7 |
| 5-40 | 7.7 | 4.2 | 7.1 | 6.3 | 7.8 |
| 5-44 | 9.4 | 5.1 | 8.7 | 7.7 | 9.6 |
| 6-32 | 9.6 | 5.3 | 8.9 | 7.9 | 9.8 |
| 6-40 | 12.1 | 6.6 | 11.2 | 9.9 | 12.3 |
| 8-32 | 19.8 | 10.8 | 18.4 | 16.2 | 20.2 |
| 8-36 | 22.0 | 12.0 | 20.4 | 18.0 | 22.4 |
| 10-24 | 22.8 | 13.8 | 21.2 | 18.6 | 25.9 |
| 10-32 | 31.7 | 19.2 | 29.3 | 25.9 | 34.9 |
| 1/4-20 | 75.2 | 45.6 | 68.8 | 61.5 | 85.3 |
| 1/4-28 | 94.0 | 57.0 | 87.0 | 77.0 | 106 |
| 5/16-18 | 132 | 80 | 123 | 107 | 149 |
| 5/16-24 | 142 | 86 | 131 | 116 | 160 |
| 3/8-16 | 236 | 143 | 219 | 192 | 266 |
| 3/8-24 | 259 | 157 | 240 | 212 | 294 |
| 7/16-14 | 376 | 228 | 349 | 317 | 427 |
| 7/16-20 | 400 | 242 | 371 | 327 | 451 |
SS Hex Bolt Size Chart
| Dia. / Thread Size | Fastener Length |
|---|---|
| 5/8"-11 | 3-1/4" |
| 5/8"-11 | 3-1/4" |
| 1/2"-13 | 1-3/4" |
| 1/2"-13 | 2" |
| 1/2"-13 | 2" |
| 1/2"-13 | 2-1/4" |
| 1/2"-13 | 2-1/4" |
| 1/2"-13 | 2-1/2" |
| 1/2"-13 | 1-1/2" |
| 1/2"-13 | 1-1/2" |
| 1/2"-13 | 1-3/4" |
| 5/8"-11 | 1-3/4" |
| 5/8"-11 | 1-3/4" |
| 5/8"-11 | 2" |
| 5/8"-11 | 2" |
| 5/8"-11 | 2-1/4" |
| 5/8"-11 | 2-1/4" |
| 5/8"-11 | 2-1/2" |
| 5/8"-11 | 2-1/2" |
| 5/8"-11 | 2-3/4" |
| 5/8"-11 | 2-3/4" |
| 5/8"-11 | 3" |
| 5/8"-11 | 3" |
| 1/2"-13 | 2-1/2" |
| 5/8"-11 | 1-1/2" |
| 5/8"-11 | 1-1/2" |
Challenges of Using Stainless Steel Hex Bolts in Acidic Environments
- Localized Pitting & Crevice Attack : Acidic conditions can trigger rapid localized corrosion, especially in tight gaps, leading to deep pits and structural weakening.
- Risk of Stress Corrosion Cracking (SCC) : When tensile stress and acidic chemicals combine, stainless steel bolts may develop cracks that grow over time and compromise integrity.
- Choosing the Right Grade Becomes Critical : Not all stainless steels perform well in acidic media. Lower-alloy grades corrode faster, while higher-alloy options like 316L or 317L offer better resistance.
- Decreased Fatigue Strength : Acid exposure can accelerate fatigue damage, reducing the bolt’s ability to handle repeated loading or vibration.
- Performance Limitations at High Temperatures : Elevated temperatures in acidic environments can speed up corrosion reactions, reducing the lifespan of bolts.
- Potential for Galvanic Corrosion : When stainless steel comes in contact with dissimilar metals in acidic solutions, galvanic reactions can accelerate metal loss.
Applications of Stainless Steel Hex Bolts
- Chemical Processing Plants
- Oil & Gas Industry
- Marine & Shipbuilding
- Food & Beverage Industry
- Pharmaceutical Manufacturing
- Construction & Infrastructure
- Automotive & Heavy Engineering
- Power Generation
- Water Treatment & Desalination Plants
- Pulp & Paper Industry
FAQs about Stainless Steel Hex Bolts
Are stainless steel hex bolts suitable for heavy-duty applications?
Yes. Grades like 304, 316, and 316L offer excellent strength and corrosion resistance, making them ideal for construction, marine, chemical, and structural applications.
Can I get custom sizes, threads, or finishes if required?
Yes — customized bolt lengths, thread types, finishes, and grades are available to meet specific project requirements.
Are stainless steel bolts magnetic?
Grades like 304 and 316 are generally non-magnetic, but slight magnetism may occur due to cold working or machining. Ferritic grades (e.g., 410, 446) are magnetic.