... , 230, 231, 232, 401 oil tempered spring steel wire (1)Dia: 1.8mm-15mm(2)Tensile strength ... quality and confidence to our partners. From wire drawing to heating furnace, all-time temperature ... range of applications:(1). Suspension spring for vechiles(2). Valve spring(3). Mechanical spring for important usage3. Material ... ) SAE6150-50CrV(4) 65Mn(5) High-carbon spring steel for VD,FD, ASTM-A229 grade I4. ...