Cupronickel 70-30 Set Screws manufactured at TorqBolt are seawater resistant,crevice resistant,stress corrosion crack resistant & hydrogen embrittlement resistant.
Dimensional standards as per DIN 913,DIN 914,DIN 915,DIN 916,DIN 551,DIN 553,DIN 438,BS 4197 are provided.
The raw material of these fasteners is classified as copper based nickels. Being a PED certified Fasteners Manufacturer by TUV Rheinland,our fasteners are accompanied with EN 10204 3.1/3.2 certification. Cupronickel 70-30 Set Screws are available in hot forged,cold forged and bar stock machined conditions depending upon the order quantity.
Copper Nickel 70-30 Is A High Content Resistant To Corrosion At Elevated High Temperatures Due To Presence Of Nickel Oxide At High Temperature. 70-30 Is Extremely Used In Offshore Industries.
Cupronickel 70 30 Set Screws — Specifications & Dimensions
Cupronickel 70 30 Set screws are externally threaded fasteners typically driven into a tapped hole or self-tapped material. TorqBolt manufactures Cupronickel 70 30 Set 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
Cupronickel 70 30 Set 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
Cupronickel 70 30 Set 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 Cupronickel 70 30 Set 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.
Copper-Nickel & Cupronickel Alloys
Copper-nickel (cupronickel) alloys combine copper's bio-fouling resistance with nickel's strength and corrosion enhancement. The two production grades dominate marine + desalination service where titanium is too costly: 90/10 Cu-Ni (~90% Cu, 10% Ni) and 70/30 Cu-Ni. Cu-Ni alloys are the only commercial materials inherently resistant to marine bio-fouling, eliminating the need for antifouling coatings on heat-exchanger tubes and ship hulls.
C70600 (90/10 Cu-Ni) is the high-volume marine alloy: yield ~105 MPa, used for desalination tubing, condenser tubes, hull cladding, and offshore piping fasteners. C71500 (70/30 Cu-Ni) increases nickel for higher strength (~160 MPa yield) and better seawater erosion-corrosion at higher flow velocities — the choice for naval condensers and high-pressure desalination. C71640 (70/30 + Fe + Mn) extends service to even higher flow rates.
Cu-Ni fasteners ship per ASTM B151 (rod/bar) and B171 (plate/forging) with EN 10204 3.1 / 3.2 certificates. Welding uses ERCuNi or ENiCu-7 filler with low-heat-input technique to avoid hot cracking. NACE MR0175 sour-service application is limited; ammoniacal stress-corrosion can occur if exposed to NH₃ in service.
