Internal piping inspection or unblocking as valve cannot be closed

[evansip]

I have a 700mm gate valve that is not sealing for whatever reason and would like to know of a method or company that can put a camera inside a main while under pressure to inspect the valve gate/seat and possible jet or remove debris.

Many options have been looked at but the main condition is that we cannot drain that system down. Freezing and line stops have been considered but are our last option.

Flow is zero (water is not moving).
Pressure is 4.5barg.
Medium is soft water.
Pipe diameter is 700mm.

All sensible comments greatly appreciated.

 

[ChEMatt]

What debris do you think could be collecting in there?

Based on what you've told me I would assume that the seat is worn and the valve needs to either be refurbished or replaced.

You could "jet" the valve by almost closing it and allowing the increased velocity through the seat clean it out.

 

[LittleInch]

1) Do you have any current tapping pont / valves / tees anywhere near it?
2) If not consider hot or cold tap with valve - You don't say what your pipe is made of
3) Once you have a valved way in then you can find a steerable camera accesible via an entry point - there's quite a few


My motto: Learn something new every day

Also: There's usually a good reason why everyone does it that way

 

[evansip]

Suspect it could be debris from construction or due to the valve arrangement (horizontal pipe, valve body in horizontal plane) the paddle could be catching on its guide. Need to confirm this.

Valve has only been installed upto 18 months ago, unsure of previous operation but surprised if seat is worn.

Valved branch not a problem. Any UK companies used for steerable cameras?

Thanks for all responses.

 

[KvdW]

I have worked with Dutch company Tecson (

http://www.tecsonmjo.nl)

for a camera inspection of the tubesheet of a large heat exchanger (on cooling water side, during operation) in Belgium.