The 8-character blind plate problem

Check HG21547-1993 and you’ll understand

Blind flanges are used to isolate pipes and are frequently employed during installation and overhauls. Compared to regular blind flanges, 8-character blind flanges do not need to be removed during switching operations (that is, when the pipeline is opened or closed); instead, only the end faces need to be swapped.

The Ministry of Chemical Industry standard \"Steel Gaskets, Washers, and 8-Shape Blind Flanges for Pipelines\" (HG21547-93) is a relatively authoritative and comprehensive standard for gaskets and blind flanges. The 8-character blind flange has a blind plate on one end and a gasket ring on the other; it comes in two types: normally open and normally closed, with the normally open type being more common. 8-character blind flanges are generally used to redirect the blind flange during production maintenance (for example, to cut off flow during maintenance when it is normally open), in order to ensure safe maintenance. Sometimes, during maintenance in production, temporary blind plates can be inserted between the flanges of certain valves. However, in many cases it is difficult to maintain a certain distance between the blind plates, in which case diagonal blind plates are used. Additionally, using 8-character blind flanges allows for clear observation of whether the pipeline is open or closed.

Blind plates serve to isolate pipes in industrial production. As the name implies, an 8-shaped blind flange is a blind flange in an 8-shaped format – one end is closed while the other is open. Once installed, it makes it easier to identify its location and status, thereby providing better safety guarantees.

8-shaped blind flanges are used in situations where the impact of the blind flange’s thickness on pipeline installation must be taken into account. Additionally, they are also employed in cases where it is necessary to clearly indicate whether a pipeline is open or closed

I’ll have to look up information on this issue by myself! ! !

An 8-character blind flange is actually a type of blind flange – one end of it is open while the other is closed. It is mainly installed in locations where blind flanges are frequently needed in order to facilitate management. When a blind flange is required, the closed end is installed on the pipeline; there is no need to turn the flange around so that the open end is used instead.

It’s actually very simple; it’s just like the number 8, except that one side is solid (a blind plate) while the other side is hollow (a hole plate). It is mainly used in pipes with a relatively large diameter, to isolate the pipe during shutdowns or maintenance tasks.

Are there any pictures I can refer to?

An 8-character blind flange is actually a type of blind flange – one end of it is open while the other is closed. It is mainly installed in locations where blind flanges are frequently needed in order to facilitate maintenance. When a blind flange is required, the closed end is installed on the pipeline, without the need to turn the flange around so that the open end faces the pipeline.