Specifications
Surface Treatments
Certifications
- ISO 9001 - 2015 Certified
- PED 2014/68/EC
- NACE MR0175/ISO 15156-2
- NORSOK M-650
- DFAR
- MERKBLATT AD 2000 W2/W7/W10
Nitronic 60 double-end stud bolts (UNS S21800) are the anti-galling austenitic stainless steel specification for ASME B16.5 flanged-joint service with through-bolt geometry. Manufactured per ASTM A193 Grade B8R chemical / mechanical and ASME B18.31.2 dimensional, the high-Mn-Si-N chemistry raises threshold galling stress per ASTM G98 by 5 to 10 times over 304 / 316L self-mated, eliminating the cold-welding failure mode that retires conventional stainless fasteners after one disassembly cycle. Nitronic 60 double-end stud bolts install dry without anti-seize, retain corrosion resistance comparable to 304, and provide non-magnetic permeability for instrumentation service. Stocked sizes 1/2 inch through 4 inch diameter, any length with custom geometry on quote.
TorqBolt stocks Nitronic 60 (UNS S21800) at our Mumbai head office and Rajkot production plant. Each consignment ships with EN 10204 3.1 mill test certification by default and 3.2 dual-witnessed inspection (Lloyds, TUV, DNV, BV) on request. Contact info@torqbolt.com or +91-22-66157017 for sized stock and lead time.
Double-End Stud Bolts stocked by TorqBolt in Nitronic 60 (UNS S21800) chemistry:
Variant with both ends machined-threaded to identical thread form. The mid-shank is unthreaded for ASME B16.5 flange-joint engagement. See stud bolts for the standard pattern.
Cr 16-18 / Mn 7-9 / Ni 8-9 / Si 3.5-4.5 / N 0.08-0.18 / C ≤0.10. See full element ranges with single and aggregate limits →
Yield 55 ksi (380 MPa) min, tensile 95 ksi (655 MPa) min, elongation 35% min (annealed). Hardness Rockwell B95-95 typical. See full mechanical specification with bar / forging / wire conditions →
Nitronic 60 threshold stress 50,000 psi+ per ASTM G98 vs 304/316L at 4,000-6,000 psi — 5 to 10× better galling resistance. See full ASTM G98 data and galling failure mechanism →
Solution anneal only at 1900-1950°F followed by water quench. No precipitation hardening response. See full heat treatment specification →
Matching filler ER218 per AMS 5847. GTAW, GMAW, and SMAW all qualified. No PWHT required for typical thicknesses. See full welding procedure →
Nitronic 60 wins for anti-galling at high temperature where 304/316L gall. Stellite is harder but brittle. vs 316L · vs Nitronic 50 · austenitic context →
For Nitronic 60 double-end stud bolts in any size or thread form, Contact the TorqBolt QA-QC team at info@torqbolt.com or +91-22-66157017. We respond within 24 hours with sized stock availability, lead time, and EN 10204 3.1 / 3.2 MTC documentation samples.
Why choose Nitronic 60 double-end stud bolts over 316L?
316L double-end stud bolts gall under tightening torque and disassembly. The cold-welding adhesion failure scores both thread surfaces, preventing reuse. Nitronic 60 chemistry (high Mn-Si-N) eliminates this mechanism. The double-end stud bolts install and break out cleanly, dry, with no anti-seize compound required.
What sizes are double-end stud bolts available in?
1/2 inch through 4 inch diameter, any length. Custom larger sizes and special head geometries quoted on a 4 to 8 week lead time. Standard UNC, UNF, metric coarse, and metric fine threading.
Are these double-end stud bolts NACE MR0175 compliant?
Yes in solution-annealed condition (95 HRB max hardness). Cold-worked HS condition may exceed the hardness limit and requires customer specification endorsement. See NACE MR0175.
What certification is supplied?
EN 10204 3.1 mill test certification by default, traceability to mill heat number and lot. EN 10204 3.2 dual-witnessed third-party inspection (Lloyds, TUV, DNV, BV) on request.
Can I get double-end stud bolts coated?
Yes. TorqBolt offers PTFE, xylan, zinc-nickel, hot-dip galvanizing, and electroless nickel plating per separate coating standards. For Nitronic 60 anti-galling service the dry-installation property usually makes coatings unnecessary; coatings are specified for additional corrosion margin in salt-spray or chemical service.
Lead time for stock vs custom?
7 to 14 days for stocked sizes. 4 to 8 weeks for custom diameter, length, or thread form. Forging stock and large diameters quote 6 to 10 weeks.