flange 1. dia:800mm-6,300mm OD custom made Pipe flange1. custom made2. large size, diameter: 800mm to 6300mm, weight of sinlge piece: 0.75 ton to 15 tons3. materials: carbon steel, alloy steel and stainless steel4. annual production capacity: 40,000 tons5. certificates: ISO9001:2008, ISO14001:2004, OHSMS18001:20076. test: ultrasonic test