24" gate valve sounds

[Fayyaz Ud Din]

We have 24" actuator mounted gate valve. While closing it near to 98 percent in last 4 to 5 turns it make sound. Same sounds when opening the valve 1 to 2 percent and then no sound. I tried it with manual operation but same sounds observed. Can any one help and let me know how to solve this problem.

 

[TugboatEng]

When a gate valve is nearly closed the flow velocity across the seat is very high. There is much turbulence behind the disk. The disk is loose in the guides and can bang around. Can you describe your sound?

 

[Fayyaz Ud Din]

Pls note
1.The sound is like friction of mechanical part,
2.the valve is checked while closing/opening when no flow accross it with having sound.
3. Seems the sound is not from seat, it's from stem side
4. No seat leak during nitrogen leak test when valve is not fully closed (98% closed) just before the sounds started.

Based in above pls advise what is this sound & how to resolve it thanks. Hope I am able to explain my problem correctly

 

[HTURKAK]

The gate valves are normally used for open or closed position. If the subject valve is used for flow and pressure control for continuous operation , turbulence and cavitation zones will develop in the pipes and fittings which can cause vibrations, and, under certain operating conditions, can cause pipe or valve material damage.

Pls look to video

https://www.youtube.com/watch?v=gRsvO4Gpnf0

and found at web needle valve.

https://www.belgicast.eu/fileadmin/user_upload/ERHARD_needle_valves_EN.pdf

 

[LittleInch]

Can you post a sectional drawing of the valve and seat.

Is the valve actually over extending?

If the valve is sealed tight at 98%,should this this really be 100%.

Who calibrated the closure percent?

What stops the actuator? Position indication or force?



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

 

[Danlap]

Agree with most post above. Appreciate if you could answer LittleInch over drawing, close indication by (maximum) force or position?, how closure position was calibrated?
I have additional question: type of gate valve (is it through conduit, standard wedge, slab)? And was it closed during high delta P?

To find where: free tool can be used is screwdriver act as stethoscope
Squeaking sounds most likely metal to metal contact:
a.Wedge vs Seat, can be caused by many reason:
-As per LittleInch, overextending, so it is actually already closed at ‘98%’ but it was over positioned by pushing the wedge with ‘strong’ actuator
-As per Hturkak, tip of the wedge might be damage due to flow control or something. And when this tip start to touch wedge, yes it will start to make sound
-Wedge might be tilted due to high DeltaP due to over-tolerance. So one side of the wedge might touch its seat pair first, before the other side touch theirs. So it is scrubbing one another until fully close.
Wedge and spindle is slot connected, basically they are just two separated parts.
b.Some valves have additional feature such as bottom of the body (cavity) has vane or wedge guide. Which might not be centered between the guide and incoming wedge
c.Miss alignment. It was repaired (and miss-aligned) or maybe wears occurred here and there overtime.
d.Something semi solid trapped at the bottom of the cavity
e.You might be right, it can be spindle vs gland. But the story is not quite added, if sounds only start at 98% to 100%, meaning there is something wrong at 95% something (top) spindle. So you should’ve seen the closing or damage section of the spindle before it closes. I won’t believe myself without screwdriver to determine source of the sounds.
Over-tightened gland or uneven spindle diameter is something else. this will cause more of jerky movement and potentially gland leakage instead squeaking sound.

Good luck
Regards,
MR

https://nosuchvalve.com

All valves will last for years, except the ones that were poorly manufactured; are still wrongly operated and or were wrongly selected

http://www.eng-tips.com/faqs.cfm?&rat1=2&fid=376

 

[HitokiriAoshi]

Your flexible wedge API 600 gate valve is flexing as it is being driven into the closed position. this is consider normal and can vary valve to valve, design to design.

1) check your actuator setting, are you torque to close? (should) have it set to 60% of max torque to open, and go up to 80% if necessary.

Luke | Valve Hax |

https://valvehax.com/