Rajtilak Metal is an ISO 9001:2015 certified manufacturer, stockist, and worldwide exporter of industrial stainless steel fasteners. Sourced and forged to the most rigorous international standards, our comprehensive product portfolio includes heavy hex bolts, fully threaded studs, hex cap screws, heavy hex nuts, and precision washers.
Engineered for mission-critical assemblies across oil and gas platforms, offshore marine projects, chemical processing plants, and cryogenic equipment, our fasteners deliver superior tensile resilience, outstanding pitting resistance, and thermal endurance under extreme operational stress.
Fully compliant with ASTM A193, ASTM A194, ASTM A320, and ISO 3506 specifications. Validated for high-pressure sour gas service meeting NACE MR0175 / ISO 15156 guidelines.
Manufactured using cold heading, hot forging, and multi-axis CNC thread rolling machines to ensure tight dimensional tolerance and optimum grain structure alignment.
Engineered for pressure vessels, flange joints, and heat exchangers. Continuously threaded and double-end studs.
High-tensile structural and industrial bolting with hot-forged heads and precision rolled threads.
Cold-formed and machined hex nuts designed to match parent bolt proof load and prevent thread galling.
Uniform load distribution and vibration-proof fastening for aggressive marine and industrial environments.
Refer to our standard manufacturing schedules covering alloy compositions, dimension standards, mechanical limits, and size capabilities.
| Fastener Type | Standard Specification | Size Range | Material Grades | Key Mechanical Property |
|---|---|---|---|---|
| Hex & Heavy Hex Bolts | ASME B18.2.1, DIN 931, DIN 933, ISO 4014 | M6 – M100 | 1/4″ – 4″ | SS 304, 304L, 316, 316L, 310, 321, 904L | Tensile: 500 – 850 MPa | Yield: 210 – 650 MPa |
| Full Thread Stud Bolts | ASTM A193, ASME B18.31.2, DIN 976 | M10 – M120 | 3/8″ – 4.1/2″ | Gr. B8 (SS 304), Gr. B8M (SS 316), Class 1 & 2 | Strain Hardened Proof Load to ASTM A193 Cl. 2 |
| Heavy Hex Nuts | ASTM A194, ASME B18.2.2, DIN 934 | M6 – M100 | 1/4″ – 4″ | Grade 8 (304), Grade 8M (316), Grade 8T (321) | Proof Load Verified to ASTM A194 Stress Limits |
| Socket Head Cap Screws | DIN 912, ISO 4762, ASME B18.3 | M3 – M64 | #4 – 2.1/2″ | A2-70, A2-80, A4-70, A4-80 (ISO 3506) | 0.2% Proof Stress up to 600 N/mm² |
| Flat & Lock Washers | DIN 125, DIN 127, ASME B18.21.1 | M3 – M100 | 1/8″ – 4″ | AISI 304, AISI 316, AISI 316Ti, Spring Steel | Hardness Rockwell B 85 – 95 HRB |
| Grade / Alloy | Carbon (C) max | Chromium (Cr) | Nickel (Ni) | Molybdenum (Mo) | Other Elements |
|---|---|---|---|---|---|
| AISI 304 / 304L (B8) | 0.08 / 0.030 | 18.0 – 20.0 | 8.0 – 11.0 | — | Si: 0.75 max, Mn: 2.00 max |
| AISI 316 / 316L (B8M) | 0.08 / 0.030 | 16.0 – 18.0 | 10.0 – 14.0 | 2.00 – 3.00 | P: 0.045 max, S: 0.030 max |
| AISI 321 (B8T) | 0.08 | 17.0 – 19.0 | 9.0 – 12.0 | — | Ti: 5x(C+N) min to 0.70 max |
| AISI 310S | 0.08 | 24.0 – 26.0 | 19.0 – 22.0 | — | High oxidation barrier up to 1150°C |
| 904L (UNS N08904) | 0.020 | 19.0 – 23.0 | 23.0 – 28.0 | 4.00 – 5.00 | Cu: 1.00 – 2.00, N: 0.10 max |
Every consignment leaving our manufacturing plant undergoes a multi-stage quality protocol in our in-house NABL-calibrated testing facility. Fasteners are marked with our proprietary hallmark, alloy classification, and individual heat number to prevent cross-contamination in heavy industrial warehouses.
Optical emission spectrometry verifies chemical heats before cold or hot heading commences.
Tensile strength, wedge tensile, yield point, and core/surface Rockwell hardness verification.
Intergranular corrosion evaluation in compliance with ASTM A262 Practice E requirements.
Thread pitch diameter, lead angle, and concentricity verified with precision optical comparators.
Regularly inspected by Bureau Veritas, DNV, SGS, Lloyd's Register, TUV, and engineers nominated by ADNOC, Saudi Aramco, and SABIC EPC contractors.
Zero scrap compromises. We forge exclusively from prime melted and ultrasonic-tested round bars sourced from world-class Indian, European, and Japanese steel mills.
Specialized surface passivations, MoS2 solid lubricant, and PTFE/Xylan fluoropolymer coatings that mitigate cold-welding tendencies on stainless threads during assembly.
Packed securely in heavy-duty polybags, moisture-barrier cartons, and steel-strapped ISPM-15 treated fumigated wooden crates designed for international sea and air shipping.
Our stainless steel bolting assemblies operate reliably across critical high-temperature, low-temperature, and corrosive operating environments worldwide.
Send your project bill of quantities or custom drawing requirements. Our technical sales engineers respond with compliant datasheets, commercial proposals, and delivery schedules within 24 hours.
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