Valve Positioner History

[danw2]

Somehow I've missed this history forum entirely, until today.

While I can't offer an answer to Jim Casey's query (thread769-114295) as to who first offered a valve positioner, an ISA article probably sheds some light on the time frame for such.

The ISA article dated August 1, 2003 entitled "Top technologies and Events" has a short paragraph on an innovation for pneumatics.

Pneumatic Instrumentation
In 1928, Foxboro's first pneumatic operational amplifier laid the groundwork for an entire generation of pneumatic instrumentation, much of it still recording industrial processes in plants around the world. A year later, Foxboro followed with the first proportional -
plus-reset (integral) controller.

Since a valve positioner is a proportional controller, the signal to it being its setpoint, the valve position being the process variable, and its purpose to zero the error between the setpoint and the valve position, I suspect Foxboro's innovation was critical to a successful proportional positioner.

And if Foxboro invented (and presumably patented) the pneumatic op amp, it's likely they'd have been in the market early on.

Dan

 

[GregLocock]

I might get around to checking the history of battleship gun turret directors. I'm a bit hazy on dates, but would guess that very soon after WW1 they would have been automated, and before then it is quite likely that the repeater in the turret had some sort of feedback to the director's positions.



Cheers

Greg Locock

Please see FAQ731-376 for tips on how to make the best use of Eng-Tips.

 

[plasgears]

This reminds me of Dornberger's book, 'V2.' He had a chapter that described the important engineering developments in that project under trying circumstances.

One was the introduction of acceleration feedback in the directional control. Their controller calculated the second derivative of displacement.

It's a book worth reading and re-reading. I lost count of the number of times.

 

[unclesyd]

I don't know when control valve positioners evolved but in the late 50's the great push was on to get a positioner on any valve that was in any type control loop.

We installed a new distillation train of 6 large vacuum columns in series with a hybrid, electronic and pneumatic, control system make by (Swartout) and control valves, sans posistioners, by Fisher. There was the biggest scramble to get positioners on everything that move up and down in field. Apparently no one believe the (Swartout) Literature about the possibilities of and for control with their instruments.