1. GB4622.2-93 spiral wound gasket pipe flange size series
2. GB9126.1-88 Asbestos rubber sheet for flat steel pipe flanges
3. GB9126.2-88 Asbestos rubber sheet for raised surface steel pipe flanges
4. GB9126.3-88 Asbestos rubber sheet for concave and convex steel pipe flanges
5. GB9129-88 Technical conditions for asbestos rubber gaskets for steel pipe flanges
6. GB9130-88 Technical conditions of metal ring gasket for flange connection of steel pipes
7. HGJ70-91 Flexible graphite composite gasket for steel pipe flange