Aisi 303 Stainless Steel Screws manufactured at TorqBolt are corrosion resistant,low maintainence,silver finish.
Dimensional standards as per ANSI B18.2.1 in imperial and ANSI B18.2.3.1M in metric 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 303 Stainless Steel Screws are available in hot forged,cold forged and bar stock machined conditions depending upon the order quantity.
AISI 303 is most easily machinable Steel of all austenitic grades of stainless steel. This property is due to presence of sulphur in the steel composition, as the sulphur content improves machining, decreases corrosion resistance although it remains good in mild environment and reduces the toughness. It is not advisable to use it in marine environments. It has good oxidation resistance when it is exposed to higher temperatures as 760 Degrees celcious. however, it starts to show carbide precipitation at prolonged exposure to higher temperatures. It is easily cold worked, however sharp bending is not advisable.
AISI 303 Stainless Steel screws are externally threaded fasteners typically driven into a tapped hole or self-tapped material. TorqBolt manufactures AISI 303 Stainless Steel screws per ASME B18.3 (socket products), ASME B18.6.3 (machine screws), DIN 912 / 7991 / 6912, and ISO 4762 / 10642, in metric M3–M48 and imperial 0–1/2".
Drive Types
Hex socket (Allen) — ASME B18.3 / DIN 912, primary for high-torque industrial use
AISI 303 Stainless Steel screws are available in cap (cylindrical), button (low-profile dome), countersunk / flat (82° or 90°), pan, fillister, truss, and shoulder configurations. Countersunk per DIN 7991 with 90° head angle is standard for metric; 82° per ASME B18.6.3 for imperial.
Thread & Length
AISI 303 Stainless Steel screws use full-thread or partial-thread (length-under-head) configurations. Machine screws are typically full-thread; cap screws use partial thread for grip control. Threading per ASME B1.1 (UNC/UNF) or ISO 965 (metric coarse/fine), Class 2A or 6g default. Length-under-head is measured from the bearing surface for hex/cap, from the largest face for countersunk. Custom lengths quoted to drawing.
Specialty Screws
TorqBolt produces AISI 303 Stainless Steel set screws (cup-point, cone-point, dog-point, flat-point, hex-socket DIN 913/914/915/916), shoulder screws (precision-ground shoulder for pivot applications), and self-tapping screws (Type AB, Type 25). All certified per EN 10204 3.1 / 3.2 with optional NACE MR0175 sour-service compliance.
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.
