I see the valve is fully open at around 20+ psi. Do you adjust the spring tension again while coupled on to achieve the bench set values on the nameplate or do you leave the valve as is?
Good question. The spring tension is only adjusted when the actuator is uncoupled from the valve. After coupling, I stroke the valve to ensure the full travel distance is achieved, which ensures the coupling process was done correctly. The spring is adjusted to the nameplate. The nameplate value was engineered to operate the valve assembly and provide adequate seating force, taking into account the forces of the process fluid and normal friction. Performing this test with the valve and actuator coupled together is called a friction analysis test, which was not covered in this video. The test is similar, but is done with the valve coupled to the actuator. Data points are gathered while opening and closing the assembly. The data points are analyzed to determine the effects of friction on the assembly. This specific control valve came from the trash pile and has significant friction, which is why we use it for training. People can get hands-on experience performing these tests and interpreting the data using a valve with real friction problems.
Say, I am using the same valve but I have been given values to start the valve travel at 11 and 13 psi as my full travel. Should I adjust the spring tension first according to these values or should I do on the positioner?
The actuator should have a rated benchset and travel distance. When the control valve assembly was engineered, the actuator specs were selected based on the force required to operate the valve. This test verifies the actuator performs according to the original design. The positioner reduces the error that is a result of mechanical friction.
Hi thanks for the video ! We bought a couple of these fisher control valves and we noticed that they don't all have the same bench set values, what's the reason for this ? I also noticed that you did your bench set from 9 to 15 psi, so when will the valve start to move? Is it 9 psi or 3 psi?
I see the valve is fully open at around 20+ psi. Do you adjust the spring tension again while coupled on to achieve the bench set values on the nameplate or do you leave the valve as is?
Good question. The spring tension is only adjusted when the actuator is uncoupled from the valve. After coupling, I stroke the valve to ensure the full travel distance is achieved, which ensures the coupling process was done correctly. The spring is adjusted to the nameplate. The nameplate value was engineered to operate the valve assembly and provide adequate seating force, taking into account the forces of the process fluid and normal friction. Performing this test with the valve and actuator coupled together is called a friction analysis test, which was not covered in this video. The test is similar, but is done with the valve coupled to the actuator. Data points are gathered while opening and closing the assembly. The data points are analyzed to determine the effects of friction on the assembly. This specific control valve came from the trash pile and has significant friction, which is why we use it for training. People can get hands-on experience performing these tests and interpreting the data using a valve with real friction problems.
@@jimdiggins101 @Jim Diggins Thank you for the feedback. This has been insightful. I look forward to seeing more of your videos
Thanks for uploading this. Makes much more sense to me now than reading the manual.
You are welcome!
Excellent work 👍
Say, I am using the same valve but I have been given values to start the valve travel at 11 and 13 psi as my full travel.
Should I adjust the spring tension first according to these values or should I do on the positioner?
The actuator should have a rated benchset and travel distance. When the control valve assembly was engineered, the actuator specs were selected based on the force required to operate the valve. This test verifies the actuator performs according to the original design. The positioner reduces the error that is a result of mechanical friction.
Thanks
Hi thanks for the video ! We bought a couple of these fisher control valves and we noticed that they don't all have the same bench set values, what's the reason for this ?
I also noticed that you did your bench set from 9 to 15 psi, so when will the valve start to move? Is it 9 psi or 3 psi?
The bench set is engineered to operate the valve based on the process stream and will determine the pressure required to open the valve.
@@jimdiggins101 thanks so much for the Response! Atleast now I know that I didn't buy the wrong things 😃
Thanks for the video! Got a question for you. Who performs the song in your video?
It was downloaded from the TH-cam Audio Library. The song is an instrumental cover of CCR's "Midnight Special", and is performed by E's Jammy Jams.
Excelente