The manufacture of large flange is commonly used in the manufacture of steel plate cutting (cold bending or rolling ring rolling to make the flange blank, and then through the large vertical lathe for machining. The production equipment of the steel plate cutting method is the most simple (investment is small, and the material utilization rate is low. Cold bending method is first forging billet to billet, then forming arc, annealing to should be after heat treatment that spelled out the whole circle in car processing to the shape and size of the design. The material utilization rate is high, and the subsequent machining allowance is smaller than that of the steel plate, but it is limited by the condition of the equipment. At present, this method is used to make the flange blank with the largest diameter of only 4m.
The large flange gasket is a kind of circular ring which can produce plastic deformation and has certain strength. Most of the gasket is from non metal plate cutting down, or by professional plant according to the rules of scale manufacturing, the data for asbestos rubber sheet, asbestos board, polyethylene plate; also useful thin metal plate will be asbestos and other non-metallic materials wrapped up made of metal gasket; and a used thin strip and asbestos belt along the winding and around gaskets. Generally large flange bearing weight is relatively large, the project is generally not easy to deformation, the key is the thickness of the problem. Large flange in the production side of the diameter are not the problem, the most well processed is their thickness. Large flange a little too thin will be easy to deformation, of course, in the production process generally does not appear in the process of deformation, in the process of machine processing will not occur, but in the use of risk. Because of the large flange in use process to carry the weight of the relatively large, coupled with the pipeline and itself weight deformation is inevitable, random in customized large flange must to take into account the large flange thickness, if unavoidable under the specific requirements to the product thin, then add hardness materials to avoid deformation.