What is the difference between installing a blind plate in front of a valve and behind it?
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Question: Is there any difference between installing a blind plate on a pipeline in front of a valve and behind it? If so, what is the difference?
It is determined whether to place it before or after the valve depending on the material on the side that needs to be isolated, mainly to prevent leakage inside the valve!
This post was last edited by ylb913 on 2015-6-22 at 11:12. The blind plates for the inlet and outlet devices that are under the management of the production workshop are located after the inlet device valve and before the outlet device valve; a blind plate can be installed only after the operation is stopped and the material has been removed. In actual production, when welding is carried out outside the valves at the inlet and outlet of the unit, the unit responsible for the system pipelines installs blind flanges in front of the inlet valve and behind the outlet valve. This is a matter of management authority across different units; it’s easy to clarify one’s own situation, but it’s not easy nor necessary to understand the situations of others. Items such as cleaning steam, nitrogen for displacement or pressurization, and fresh water used only during startup and shutdown are all equipped with blind flanges in front of the root valve to facilitate easy removal and installation at any time.
The purpose of installing blind plates is to completely isolate the material, which is generally determined based on the flow direction of the material.
Blind valve can also be used! Our blind valve is generally used in conjunction with butterfly valves! The butterfly valve is at the front, and the blind flange valve is at the back. The butterfly valve has poor sealing, but it is adjustable. The blind valve is 100% sealed. The two are combined with each other
Based on the function of the blind flange and the requirements of the materials upstream and downstream, it is determined how to isolate them in order to decide on the location of the blind flange!
It is designed to block the material in front of the valve, and the same applies behind the valve.
It should be added after the valve, with the purpose of preventing leakage inside the valve and providing a second layer of sealing.
This depends on the process conditions. In any case, the goal is to prevent the valve from failing to close properly, which could lead to material leaking in. As long as safety is maintained, it should be added in the most convenient way possible.
It is added according to the flow direction of the medium; turn off the valve and then adjust the blind plate
Following the flow direction of the material, it is installed behind the valve; the purpose of installing a blind plate is to prevent leaks inside the valve, as it is a measure taken for that reason