... in manufacturing fasteners such as bolts,screws,studs,nuts,washers,threaded Rods,pins,rivets,stamping,circlips and other nonstandard parts. ... :1. High strength alloy steel double end stud- , fully-threaded stud and heavy hex nut applied on petrochemical industry, boiler ... 70, A4-80. Material: 304, 316, 316L.6. International internal and external hexagon bolt with the mechanical property of Grade 4.8 ...