Repair of Leaking Fuel Oil Pipe
Repair of Leaking Fuel Oil Pipe
(OP)
My subcontractor installed 2" threaded steel pipe for the fuel lines for new emergency generators per the engineer's specifications. The problem is leaking at the joints. He has already made repairs on (3) different ocasions without success. He has changed fittings, pipe sections and pipe dope. His latest proposed solution is to cut out the section with the leaking fittings an replace with socket welds. Does anyone know where I can find the industry standards for this procedure? I am hesitant (to say the least) to allow this subcontractor near the pipe with any type of hot work.
Thank you
Thank you





RE: Repair of Leaking Fuel Oil Pipe
It wouldn't be the first time a die was used without the correct taper (or none at all like conduit)
RE: Repair of Leaking Fuel Oil Pipe
RE: Repair of Leaking Fuel Oil Pipe
You might check the dope that's being used. Some are limited to a maximum of 1-1/2" pipe. The manufacturer will also list the fluids they're good for, along with pressure & temperature limitations.
RE: Repair of Leaking Fuel Oil Pipe
threads leak because of the reasons mentioned in the previous posts.
vibration can also make a threaded joint leak.
in an installation with leaky threaded joints we added flexible pipe sections at strategic points (there are several manufacturers like swagelok, parker, etc) never had a leak again, and still kept the maintainability of the installation.
granted, there will be an extracost... buying the flex-pipe... but this negotiation is beyond the question raised.
saludos.
a.
RE: Repair of Leaking Fuel Oil Pipe
my opinion only, i would never use a threaded joint > 1" diameter for a fuel piping system. even then, i would limit the number of threaded joints (test and inspection locations). i would plan the routing of pipe to avoid obstructions and ease of maintenance. socket weld and flanges with flextallic gaskets, regardless of design pressure and temperature. threaded joints are a weak joint and are eventually prone/susceptible to leakage; hence, a fire hazard. hence, my justification for not using threaded joints. as far as the welding, use a qualified welder that has successfuly passed the weld procedure/qualification. again, my opinion only.
good luck!
-pmover
RE: Repair of Leaking Fuel Oil Pipe
Antone know if this is true? Like I said I didn't look into it.
Good luck,
Latexman
RE: Repair of Leaking Fuel Oil Pipe
What you said about fuel being hard to seal is more true of gas oil, especially when it's hot. Hot gas oil will seep through almost any threaded connection. Hot fuel oil can do the same thing. But the fuel oil that we are talking about here is diesel fuel (I assume) and low temperature. Cold fuel oil shouldn't be tough to seal. It could be bad threads like some posts mention or high vibration / engine movement like others mention. I believe it is probably that later. If it's an engine it has to move and the piping has to be able to take the movement.
RE: Repair of Leaking Fuel Oil Pipe