Grinding of a gas pipeline
Grinding of a gas pipeline
(OP)
We've got to do a strain gauge installation of a gas supply pipe to monitor it for stress changes due to subsidence. (about 8" dia)
As for normal strain gauge installations, we need to prepare the surface by grinding away paint and getting a nice smooth surface finish.
Problem for me is grinding sparks and gas don't mix very well.
The boss says we'll be fine, just bring a gas metre and it'll be alright.
I'm thinking adequate prepartaion for this is to write my will and get an extra life insurance premium.
Any thoughts?
As for normal strain gauge installations, we need to prepare the surface by grinding away paint and getting a nice smooth surface finish.
Problem for me is grinding sparks and gas don't mix very well.
The boss says we'll be fine, just bring a gas metre and it'll be alright.
I'm thinking adequate prepartaion for this is to write my will and get an extra life insurance premium.
Any thoughts?





RE: Grinding of a gas pipeline
RE: Grinding of a gas pipeline
Ensure meter is currently calibrated, the 'bump' test it.
Walk the area your working in, looking for evidence of leakage, and watching the meter
Get in the hole, and test the air in the extreme bottom of the hole.
If no problems, go to work.
NOTE: unless you've been using a grinder many times a week, for many years, do not 'grind' on a live line; you won't have a delicate enough touch. Use something less aggressive, like a sanding disk or flapping pad [aka Tiger Pad] to ensure that only enough 'crust' gets removed to expose shiny metal. Don't remove any metal. Simple.
RE: Grinding of a gas pipeline
Sniff area first for LEL's, remove coating or with a wire wheel remove coating, get a fine disc for the grinder (80 grit or higher). Slowly polish surface. You will only need to take off a couple thousands of an inch material to get a polished surface. We do this all the time for installation of strain gauges, we also have other procedures for grinding out defects such as cracks on pipelines. As long as there is no issue in the area your grinding (such as severe wall thining) you'll be okay. You can take a wall thickness reading before you start grinding.
RE: Grinding of a gas pipeline
Condisdering that we'll weld to operating hydrocarbon lines and vessels (patches, encapsulations, hot taps, etc), grinding in most conditions is easy.
RE: Grinding of a gas pipeline
MJCronin
Sr. Process Engineer
RE: Grinding of a gas pipeline
I should have said that we're using sanding discs and not angle grinders, although we do start with 36 grade and work our way up to 120- there are still sparks.
Maybe I'll do it with a light touch
RE: Grinding of a gas pipeline
But be there, with your boss! , when your tech's are doing it.