... customer's drawings. 3Certificate:ISO9001:2008,SGS Tortous type high tensile bolts and nuts washers for steel structures 10.9 >> We ... highway, bridge, boiler with steel structure,industry workshop,high civil buildings, hoisting machinery and so on. Our strength on exporting: 1.Our ... 2.From 2006, we have manufactured the products of high speed railway and now they are being used. We exported to world ...