Great videos! I’ve been working in a valve shop, breaking down then refurbishing and rebuilding valves and actuators, with a factory trained mechanic. The videos really help me learn more without having to bother my coworker to train me every moment. I bench set a fisher 657 size 45 to 3-18psi with the stem taking off around 3.3. Thanks!
Another important aspect of setting bench sets (b.s.) is to know which type of "valve assembly" (valve & actuator) direction you're working on? If you have a "push down to close" valve coupled to a "air to retract" actuator, this is a "Fail Closed valve assembly (v.a.). However, a "push down to open" valve coupled to the same "air to retract" actuator, results in a "Fail Open" valve assembly. This is important from the standpoint of a "Fail Closed" valve assembly the lower end of the bench set is important & the pressure setting should never be lower. In a "Fail Open" v.a., the upper end of the b.s. should not be exceeded as the difference between the upper b.s. & the regulator setting determines the trim (valve) load.
Hi I've purchased quiet a bit of these fisher control valves, and I've noticed that not all of them have the same bench valves. Example some is 9 to 15 psi Etc Now the question that I got, is will the control valve be able to open from 3 to 15 psi ? And also why come with different bench set values ?
Standard butterfly valves usually control best at between 30 and 50% of travel. They are inherently quick opening because as they come off the valve seat the disk opens up at both the top and bottom of the disk, allowing flow to jump very quickly. Emerson offers a special butterfly valve called a Control-Disk which has a specialized disk that helps it control over a wider control range. Watch this video to learn more about it. th-cam.com/video/ubTcwCh9I4w/w-d-xo.html
The values listed on the actuator nameplate assume no valve friction is present in the assembly so it generally suggested that the stem coupler be removed. You can, however, adjust the bench set and spring compression with the actuator coupled to the valve but you’ll have to account for the frictional dead band of the assembly, which then would need to be added to or subtracted from the bench set values listed on the name plate. If the frictional dead band is not accounted for and adjustments are made so that the valve responds only to the values as they appear on the nameplate, then you’re going to run into issues of either too much or too little spring compression that what the actuator and valve were originally sized and designed to operate with, which could lead to issues with fully opening or closing the valve, seat load issues for shut off and seat leakage, with standing stem loads as process forces are applied to the plug.
Great videos! I’ve been working in a valve shop, breaking down then refurbishing and rebuilding valves and actuators, with a factory trained mechanic. The videos really help me learn more without having to bother my coworker to train me every moment. I bench set a fisher 657 size 45 to 3-18psi with the stem taking off around 3.3. Thanks!
Thanks for the kind words Matthew. We're glad you found it useful!
Dear sir,
Give me suggestions about Fisher V200 valve.like how to going air pressure input and output..
Another important aspect of setting bench sets (b.s.) is to know which type of "valve assembly" (valve & actuator) direction you're working on? If you have a "push down to close" valve coupled to a "air to retract" actuator, this is a "Fail Closed valve assembly (v.a.). However, a "push down to open" valve coupled to the same "air to retract" actuator, results in a "Fail Open" valve assembly. This is important from the standpoint of a "Fail Closed" valve assembly the lower end of the bench set is important & the pressure setting should never be lower. In a "Fail Open" v.a., the upper end of the b.s. should not be exceeded as the difference between the upper b.s. & the regulator setting determines the trim (valve) load.
Thanks a Lot from Guanajuato México.
what is the difference between bench set and bench range?
Hi
I've purchased quiet a bit of these fisher control valves, and I've noticed that not all of them have the same bench valves.
Example some is 9 to 15 psi
Etc
Now the question that I got, is will the control valve be able to open from 3 to 15 psi ?
And also why come with different bench set values ?
What is the difference between Operating rang and bench set ???
How shall we adjust both
In failure Open and failure Close valve ??
LOVING YOUR VIDEOS...! THANKYOU
Why are you only using direct acting valves? How about reverse acting?
What is the name of equipment test you used in this video?
You're the best!
tyty
Excellent. 👍👍👍
Excellent
Why does my butterfly valve does not control well for low flow rates
Standard butterfly valves usually control best at between 30 and 50% of travel. They are inherently quick opening because as they come off the valve seat the disk opens up at both the top and bottom of the disk, allowing flow to jump very quickly. Emerson offers a special butterfly valve called a Control-Disk which has a specialized disk that helps it control over a wider control range. Watch this video to learn more about it. th-cam.com/video/ubTcwCh9I4w/w-d-xo.html
Is it necessary to perform the bench set with the actuator stem uncoupled from the valve stem? I adjust the spring tension with them coupled.
The values listed on the actuator nameplate assume no valve friction is present in the assembly so it generally suggested that the stem coupler be removed. You can, however, adjust the bench set and spring compression with the actuator coupled to the valve but you’ll have to account for the frictional dead band of the assembly, which then would need to be added to or subtracted from the bench set values listed on the name plate. If the frictional dead band is not accounted for and adjustments are made so that the valve responds only to the values as they appear on the nameplate, then you’re going to run into issues of either too much or too little spring compression that what the actuator and valve were originally sized and designed to operate with, which could lead to issues with fully opening or closing the valve, seat load issues for shut off and seat leakage, with standing stem loads as process forces are applied to the plug.
Sir hindi me please please