Hexagon Bolts
- ANSI B18.2.1
- ANSI B18.2.3.1M
- DIN 931
- DIN 933
- BS 1768
- UNI 5731
- UNI 5737
- UNI 5739
- ISO 4014
- ISO 4017
- BS 1769
- BS 3692
Draw bolts are externally threaded fasteners with an integral head, manufactured per ASME B18.2.1, ISO 4014/4017, and DIN 933/931. TorqBolt produces Draw bolts in metric (M6–M100) and imperial (1/4"–4") diameters with custom lengths from 10 mm up to 3000 mm.
Draw bolts are supplied with full or partial threading. Full-thread (UNC, UNF, ISO metric coarse/fine) for tension-only joints; partial-thread shank for shear loads where the unthreaded grip carries the load. Thread fits per ASME B1.1 (Class 2A) or ISO 965 (6g) by default; tighter Class 3A / 4h6h fits available on request. Engagement length follows the 1.5×D rule for tapped holes; 1.0×D minimum on through-bolting.
Draw bolts achieve characteristic tensile strength, yield, and elongation per the source-material spec, with proof-load testing and hardness verification per ASTM F606 / ISO 898-1. Torque-tension calibration is published per ASME PCC-1 for critical joints. Each lot ships with EN 10204 3.1 (or 3.2 on request) certificates listing chemistry, mechanicals, hardness, and dimensional inspection.
TorqBolt can produce Draw bolts to drawing, with non-standard heads, drilled-shank variants, double-end, captive, or matched-set configurations. Coatings include zinc, PTFE, Xylan, hot-dip galvanized, and electroless nickel. NACE MR0175 / ISO 15156 sour-service certification on request.
TorqBolt manufactures specialty fasteners across the full range of corrosion-resistant alloys (CRAs), high-temperature superalloys, and engineered metallurgies required by the process industries. Beyond the high-volume Inconel, Hastelloy, Duplex, and stainless grades, our supply chain covers a long tail of specification-driven alloys for unique service envelopes — sour wells, extreme cryogenics, pharmaceutical-grade purity, oxidizing acids, chlorinated solvents, and high-temperature cyclic-load fasteners.
Each specialty alloy is sourced from approved mills with full melt traceability through a closed forging route. Heat-treat condition, mechanical properties, and corrosion testing are controlled to the customer's drawing or governing specification — whether ASTM, ASME, AMS, MIL, NORSOK, NACE, or proprietary end-user codes. EN 10204 3.1 (mill cert) or 3.2 (third-party witnessed) material test certificates are issued with every lot, listing chemistry, mechanicals at relevant test temperatures, hardness, dimensional inspection, and any corrosion or NDT test results required.
Third-party inspection by TUV, Lloyd's, BV, DNV, SGS, and Intertek is arrangeable. NACE MR0175 / ISO 15156 sour-service qualification, NORSOK M-650 mill qualification, API 6A wellhead bolting, API 20E subsea bolting, and PED 2014/68/EU pressure-equipment compliance available across the alloy range as the application demands.