I know this is a long one but please take the time to read it, Thanks.
I was recently working on a Volvo 460 Excavator. It had a pinhole leak on the right boom cylinder hydraulic tube at the weld (this is for the barrel end of the cylinder) I knew I had to remove the tube to re-weld it. So, knowing the dangers of high pressure oil being released when I tried to remove the tube I refered to the operators manual for the proper procedures to relieve the pressure....
1: Remove the cap for the hyd tank (vent pressure)
2: Turn on the key (without starting the engine) and move the control levers and travel pedals for a few seconds
This is a newer machine, all the hydraulic valves (except the ones for the travel motors) are electronically controlled (electronic + pilot) therefore simply turning on the key will not be sufficient to actually move the spool and vent the pressure from the cylinder!
I knew this before hand and took extra precautions (2 pairs of gloves, face shield, long sleeve shirt) I also wrapped several rags around the fitting I was going to remove and loosened the bolts furthest away from me.
When I did loosen the fitting enough the oil rushed out with enough force to split the o-ring, SHRED the rags and hit the cab so hard it sounded like someone had hit it with a hammer! this is extraordinarily dangerous!
Once back at the shop I discussed this with the safety manager, his response to me was that he had already run the manufactures procedures by the ministry ("of labour" I think) and that they were satisfied with it! Total BS!!!
My question is: Does anyone have a better way to do this? or some kind of safety device to contain the escaping oil?
(My idea was to build some kind of collar to contain the oil but this would not work in all applications...)
Thanks for any help