Just figured I would throw this one out there in case anyone can help. We are currently laying 650mm steel pipe which has a cement lining. Problems we are having is that in order to slide the pipe in past the rubber the machine builds up that much pressure that we then shoot past the witness marks and send the pipe home. The pipe we are laying is only allowed to be 5 mm either side of the witness marks so is very easy to go in to far. Any ideas? Oh by the way the pipes are 12metres long and way 2 tonnes each. I am using a 33tonne cat and just above idle nudging it along, as soon as the pressure goes on I stop moving. Am not expecting someone to have the answer for me as we think we are in a one of type situation but a bit of debate might give us some ideas. Thanks
Put a medium sized hydraulic jack or a port a power inbetween the bucket and the pipe and push the pipe together with that.
It sounds like you need more control when pushing the pipes into one another, what you have with the excavator is not fine enough. I worked on a job one time where miles of 12-m sections of 400mm diameter spun cast iron pipe with concrete linings were assembled and the guys doing that job were pulling each pipe into position using a beam across the end of the pipe and 2 hydraulically-powered come-alongs anchored to the previous pipe in order to get the correct depth in the joint. You don't say whether or not you're using a lubricant on the rubber joint. If you're not using one maybe then maybe you could consider it.
Thanks guys. Yes we are using lube, and they seem to be sliding in fairly easy, your point about the amount of control is right, just not sure how we can get around it, part of the problem we are having is the safety rules we are working under here. For a start we cant use soft slings to lift the pipe as soft slings are banned on site. Cant use a chain as it will damage the 2mm plastic coating on the pipe. So we are using a vac lift on the pipes, which then means we cant use a jack of the boom. Will try to post some pics tomorrow. It doesnt seem like this is going to be our problem now as the back fill crew are taking 2 days to back fill what we are laying and we are meant to have the fence backfilled each day. If its not one thing its another lol.