Regarding the eight-character blind flange?
Thread Content
In installations, for pipelines that are not used frequently, such as those for priming with oil at the start-up phase or for steam purging, diagonal blind plates are generally installed at the valves with flange connections on these pipelines. These blind plates are usually placed upstream, but they can also be installed downstream, for example at the locations where waste oil is discharged. May I ask everyone, is there any particular consideration regarding whether it should be installed upstream or downstream of the valve?
Should the blind flange be installed upstream or downstream of the valve? It depends on whether it is easier to install it in that position! For the main steam line of the unit, it must be installed by shutting off the boundary valve. If you install it upstream, when steam comes in, it’s difficult to press. There is also the location of the installation space. I don’t feel anything else. Steam purge line valves are generally equipped with a dual-valve assembly. The eight-character blind plate can be installed directly between Valve 2.
Whether the eight-character blind plate is installed upstream or downstream of the valve depends mainly on whether it is convenient and safe to remove and install it.
If the pipelines in the device are not used frequently, diagonal blind plates are generally installed between the two valves at the boundary to facilitate use and ensure safe installation.
Generally speaking, considering the flow direction of the pipeline medium, it is recommended to install it at the flange behind the valve!
I asked the experienced technicians in the facility; regarding the installation direction of the eight-character blind plates, it is necessary to consider that installing them in the upstream direction can prevent the valve stem and valve core from being washed by the fluid and reduce corrosion, whereas installing them in the downstream direction does not provide any such protection.
Blind plates are generally installed downstream of the fluid to facilitate installation and removal.
Before the unit is put into operation, the valves should be in a closed state, and the eight-character blind plate should be installed on the side without any medium
The main consideration is to facilitate the installation and removal of the blind plate without affecting the normal flow of materials in the upstream and downstream pipelines. Those equipped with double valves are generally installed between those valves.
Whether it is installed upstream or downstream depends mainly on whether the valve can serve as a barrier when a transition blind plate is used
The installation location of the 8-character blind plate should be determined based on the actual conditions of the process. Generally, the blind plate should be installed behind the valve, mainly to isolate a certain device or section of the system, thereby facilitating the installation or removal of the blind plate. There is no unified standard for this; whether it should be installed in front of the valve or behind it depends on the actual conditions of the process. The guiding principle is to ensure safety during maintenance or operation!