our company is adopting the standards, such as astm, din, en, gost, jis, ped, and rules for ships. od ranges from 6 mm to 630 mm, and wt ranges from 1 mm to 30 mm. the main material are 304/l, 316/l, 321/h, 310s, etc. the products are widely used in fertilizer, petroleum, central-station, boiler, power station, shipping military, chemical industry, environment protection, traffic, metallurgy and mine, printing and dyeing, food industry, medical equipment, and so on.