Aisi 348 Stainless Steel U Bolts manufactured at TorqBolt are corrosion resistant,low maintainence,silver finish.
Dimensional standards as per DIN 3609 are provided.
The raw material of these fasteners is classified as Austenitic Stainless Steel. Being a PED certified Fasteners Manufacturer by TUV Rheinland,our fasteners are accompanied with EN 10204 3.1/3.2 certification. Aisi 348 Stainless Steel U Bolts are available in hot forged,cold forged and bar stock machined conditions depending upon the order quantity.
AISI 348 Stainless Steel U Bolts — Specifications & Dimensions
AISI 348 Stainless Steel U bolts are externally threaded fasteners with an integral head, manufactured per ASME B18.2.1, ISO 4014/4017, and DIN 933/931. TorqBolt produces AISI 348 Stainless Steel U bolts in metric (M6–M100) and imperial (1/4"–4") diameters with custom lengths from 10 mm up to 3000 mm.
Head Styles Available
Hex head — ASME B18.2.1, the workhorse for general bolting
Heavy hex head — thicker head for high-load joints, ASTM A325 / A490 patterns
Socket head cap (SHCS) — ASME B18.3 / DIN 912, ideal where space is limited
AISI 348 Stainless Steel U 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.
Mechanical Performance
AISI 348 Stainless Steel U 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.
Custom Configurations
TorqBolt can produce AISI 348 Stainless Steel U 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.
Austenitic Stainless Steel (300-series)
Austenitic stainless steels form the workhorse 300-series — face-centered cubic Fe-Cr-Ni alloys delivering excellent corrosion resistance, formability, weldability, and toughness from cryogenic to ~600°C. They are non-magnetic in the annealed condition and the default choice for food, dairy, pharmaceutical, marine, and general process-industry fasteners.
AISI 304 (18Cr-8Ni, UNS S30400) is the baseline; 304L (low-C) prevents weld sensitization for thicker sections. AISI 316 adds 2-3% Mo for chloride pitting resistance, and 316L is the welding-grade marine standard. 309 / 310 are the high-Cr grades for elevated temperatures (to ~1100°C). 321 / 347 are Ti / Nb-stabilized for stress-relieved welded service. 304LN / 316LN add nitrogen for higher yield without sacrificing corrosion.
Austenitic fasteners are supplied per ASTM A193 grade B8 (304), B8M (316), B8T (321), B8C (347) and ASTM A276 / A479 for general bar. EN 10204 3.1 / 3.2 certs cover mechanicals, hardness (HB ~150-217), intergranular-corrosion testing (ASTM A262 Practice E), and surface condition. NACE MR0175 sour-service compliance maintained below the hardness threshold for SSC.
