From the appearance, blind plates are generally divided into flat plate blind plates, 8-shaped blind plates, insert plates, and gasket rings (insert plates and gasket rings are blind to each other). Blind plates serve the same function as heads, pipe caps, and welding plugs in terms of isolation and cutting. Due to its good sealing performance, it is generally used as a reliable isolation method for systems that require complete isolation. A flat blind plate is a solid circle with a handle, used for systems that are typically in an isolated state. And the 8-shaped blind plate, shaped like an 8-shaped, has one end as a blind plate and the other end as a throttling ring, but its diameter is the same as the diameter of the pipeline and does not have a throttling effect. The 8-shaped blind plate is easy to use. When isolation is required, the blind plate end is used. When normal operation is needed, the throttling ring end is used. It can also be used to fill the installation gap of blind plates on pipelines. Another characteristic is clear labeling, making it easy to identify the installation status.