KeithW wrote: ↑Sun Apr 21, 2019 19:36
The issue of variable quality in old work applies around the country, in the absence of a quality control regime it often comes down to the level of diligence of the site engineer. Many years ago I worked on a job that involved replacing some of the cooling water pipework at a power station which had been found to be substandard. As was common in the mid 1960's when it was installed the specification for welding was simple succinct and utterly useless reading as it did 'All welding shall be to a good commercial standard'. We were informed that 2 different contractors had been used. One had enforced good standards and adopted the policy of enforcing 10% radiography even though the contract did not call for it. They had even retained the radiograph films. The work done by this contractor was in good condition and was largely left untouched. That done by the other was appalling and it was a miracle the Turbine Hall basement had not been flooded by a failed weld. A failed 24" pipe can release a LOT of water very quickly. The steam pipework was fine as there had been a quality control system in place for it. When you are employing men who are paid a bonus for finishing quickly short cuts will be taken.
First job out of university was overseeing such work in 1980.
The welders and pipefitters were different unions. Best of mates but knew absolutely the official dividing line between their trades. They were paid (including bonus, always paid) by the hour, including time waiting for the other trade to turn up or finish.
On Sundays the client's engineer did not come in, but reviewed daily progress on Monday morning. Therefore a different arrangement applied, known as "job and knock". Foreman said what work was to be done, when finished you can go (my job, among others, was to stay behind after they left and put all their timecards through the clock at normal finishing time, but that's another matter).
Union distinctions were forgotten. If there was no welder to hand the pipefitter would pick up the welding kit and do it - and the welders would expect them to do so to get away by lunchtime.
Now we also had x-ray of the welds, some on a percentage basis, more critical ones 100%. The inspector from National Vulcan, who did this work then, came around, but only I had the progress sheets which showed who did what and which ones were done on a Sunday (the pipefitter ones were put against the welding foreman). Do you know, the failure rate (and overall there were very few) for porosity etc was no worse on what the pipefitters had done than those by the qualified welders.