ຂໍ້ມູນຈໍາເພາະ TB/T 897-1999 ຕາ bolt TB/T 896-1999 ຕາ bolt TB/T 1479-1991 railway car axle shaft bolt QC/T 599-1999 end face bolt welding QC/T 59998-1999 Wearing surface bolt QC/T 518-1999...