Conduit to Cable Seal?

[sloquick]

Anyone have experience and/or suggestions on how to seal around FO cable exiting a conduit. Sheath of cable and conduit are both polyethylene. Can't access ends. Must be able to contain 100 psig of gas in conduit. Thanks!!!!

 

[hacksaw]

I don't think that your cable sheath has adequate pressure rating. So even if you do take a packing gland approach you stand to have leakage.

By the way, you need to be extremely cautious if you are planning to pressurize the conduit. You may be running into safety regs and increasing the risk of injury to your maintenance crews.

Case in point is that the electrical codes do not consider conduit as "pressure piping", yet that appears to be the focus of your question.

If it is pressurized then you need to conform to the piping codes such as B31.3 (as a minimum) and have provision for safety relief in the event of fire, etc.

Electrical feed throughs are available for process feed throughs.

 

[sloquick]

Hacksaw;

Thank you for your reply.

The conduit is certified gas pipe. It is installed inside a larger diameter pipeline that operates with gas pressure up to 60 psig. The conduit will only see pressure internally if there is a failure that breaches it. My primary interest is containing the gas inside the conduit should this occur. I need to do this where conduit has exited the pipeline and terminates with the cable coming out of it. The cable has a fairly thick polyethylene sheath that should be gas tight unless it also has developed a breach which is another problem for which I believe I have an acceptable solution already.

Since the cable may go into another conduit that enters the pipeline before a seal is applied, a two piece assembly is implied if mechanical.

Thanks for your interest.