Actuator Stem bend 1

[Isha90]

Customer complaint Actuator operated Globe Valve Stem bend, so I had requested customer to provide Service media, Actual & Max operating pressure/ temperature, Photos of valve & actuator from site, could anybody guide me in finding out reason of failure please.

 

[MikeHalloran]

Certainly, yes, anybody could guide you, had you revealed any of the information items you mentioned.



Mike Halloran
Pembroke Pines, FL, USA

 

[btrueblood]

Reason for failure? It sounds like the valve stem bent.

 

[gerhardl]

Serious:

Either the stem was too weak (to slim, unsupported) for a normal closing force, or limit or torque switches were out of function, missing or wrongly adjusted. The last is the most common cause.

And a multitude of other causes, if you can give us more facts. (Why did the car end up in the ditch?)

 

[Isha90]

Thank you, Valve Stem MAST 1.5 > Actuator torque mentioned in Catalog,I am awaiting details please,

 

[MikeHalloran]

WHAT CATALOG? WHICH VALVE? WHICH ACTUATOR?

DO YOU UNDERSTAND HOW THIS WORKS?

WE CAN'T SEE WHAT'S ON YOUR DESK.

WE DON'T KNOW WHERE YOU WORK, OR FOR WHOM.

WE DON'T KNOW WHAT YOU BOUGHT, OR FROM WHOM.

WE DON'T KNOW WHAT YOU SHIPPED, OR TO WHOM.

IF YOU ARE AWAITING DETAILS FROM US, YOU WILL BE WAITING A LONG TIME.



Mike Halloran
Pembroke Pines, FL, USA

 

[Isha90]

Sorry i waiting for details from my customer, i wanted to know probable cause of failure please

 

[jmec87]

Isha90, in order to maximize the usefulness of this forum and to minimize the annoyance to other forum members who want to help you, I recommend only asking "Why did it fail?" if you also provide some details about the failure. Simply asking "Why did it fail?" without providing any information about the failure is unlikely to result in helpful responses.

 

[ValveWagen]

There are some possibilities to this stem bending.

1) Stem was not properly installed and causes it to bend
2) Stem size is too small or wrong selection of stem material(weak) which the actuator force causes it to bend, please check actuator sizing.
3) Over supply of air pressure to the actuator (positioner & regulator failure), but very rare.

 

[Isha90]

Thank you

 

[HitokiriAoshi]

i am going to assume you meant valve buckled.

the only reason is over application of strength for the stem for the way the stem is supported.