Alloy 333 Allen Screws Specification

Alloy 333 Equivalent Designation
| UNS Designation | British STD | Werkstoff No. | European STD | Swedish STD | Japanese STD |
|---|---|---|---|---|---|
| – | – | – | – | – | – |
Alloy 333 Allen screws are externally threaded fasteners typically driven into a tapped hole or self-tapped material. TorqBolt manufactures Alloy 333 Allen 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".
Alloy 333 Allen 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.
Alloy 333 Allen 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.
TorqBolt produces Alloy 333 Allen 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.
High-nickel superalloys beyond the Inconel + Hastelloy family include specialty grades engineered for unique service envelopes — ultra-high-temperature furnace components, oxidation-resistant structural alloys, and corrosion alloys where C-276 reaches its limits.
Alloy 230 (UNS N06230) is a Ni-Cr-W-Mo solid-solution alloy combining the high-temperature strength of Inconel 625 with superior oxidation resistance to 1150°C — the standard for gas-turbine combustor cans and reformer tubes. Alloy 330 (N08330) is a Fe-Ni-Cr alloy for cyclic-temperature furnace fixtures. Alloy 333 (N06333) extends the envelope with higher Mo+W. Alloy 602 CA (N06025) achieves the highest oxidation resistance of any wrought Ni-base alloy at 1200°C+ via Al + reactive-element additions. Alloy W (N10004) is a Ni-Mo-Fe-Cr alloy for sulfuric and reducing-acid service.
These specialty alloys ship per ASTM B435 / B574 / B575 with EN 10204 3.1 / 3.2 certification including chemistry, mechanicals at room + elevated test temperatures, hardness, and oxidation / corrosion testing per the application's requirement. Welding requires matched-composition filler with strict control of dilution.