Total production of these custom large grade 5 threaded stud socket bolts was run at approximately 27,000 pieces using grade 5 steel material per SAE J429 with zinc clear finish per ASTM B633 Type III. Overall length of the bolts was 6" and a .566-.573" socket drive was incorporated on one side. Core hardness was tested a number of times to confirm Rc25-34 and proof load testing was done at three separate labs to confirm 85,000 psi minimum. Full certs were provided with the parts.
We had 1,100 pieces of these custom metric dacromet coated u-bolts produced using 42CrMo material with heat treat hardening. The part was originally designed to be made using 17-4PH stainless steel material but a number of attempts resulted in multiple failures during bending - the material was too hard and repeatedly snapped as the tool pressed the 90 degree corners. As a result we switched to the 42CrMo material with heat treat to obtain the required hardness and strength, with a combination of the dacromet coating to achieve the corrosion resistance needed. Turned out to be a much trickier part than originally anticipated!