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Help identify P&ID symbol

Help identify P&ID symbol

Help identify P&ID symbol

Hi - I have attached a picture of the symbol. It is the one to the left of the pH meter. It is part of a pH water control loop. Does anyone know what it could be? The piping is 3/4" PVC SCH80. I think it is some kind of check valve w/ injection port or bleed port. Thanks in advance.

RE: Help identify P&ID symbol

My guess is: Three-way-valve

Sometimes its possible to do all the right things and still get bad results

RE: Help identify P&ID symbol

a slightly bigger snapshot would help a bit. why are there two lines coming out on the LHS of this item?

Is it some sort of sight glass?

Remember - More details = better answers
Also: If you get a response it's polite to respond to it.

RE: Help identify P&ID symbol

Here is a picture of what it actually looks like in the field. You are looking directly at it. The flow is from the back and then down I think. So that is the question: What is this? And also why are there two lines coming out that go to nothing, I don't know that's all there is? I apologize for the picture quality it's all I have.

RE: Help identify P&ID symbol

My thoughts are that is a probe, assuming to measure pH. In the picture, the flow comes into the right of the fitting, turns down, and flows across the outside of the probe. It may require actual flow across the element versus just tapping into a threaded connection and having a stagnant spot.


RE: Help identify P&ID symbol

Looks like a flow cell. Some of the pH instruments now how multi-function such as temperature monitoring.

RE: Help identify P&ID symbol

What does the Process Diagram Legend Sheet say?

Sometimes its possible to do all the right things and still get bad results

RE: Help identify P&ID symbol

Umm yes, if there was a key or legend or an answer in the back of the book, I wouldn't waste everyone's time. On the legend there is a flow switch entry that doesn't have any pictogramme associated with it so just to further muddle the matter...I don't think its a flow switch but its possible I guess, kind of a weird symbol for a flow switch.

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