UCC was generally unaware of warranties on anything less than complete systems (bleach plants, digesters, paper machines, sheeters, etc). I can recall one particular incident where we should have.
We upgraded three wash lines which meant replacing all repulper dilution pumps and vat dilution pumps. The old ones were OLD A-C pumps (big, massive castings). The new ones (over double the capacity) weren’t as big physically. Soon after start-up one of the new pumps (double suction) suffered a total fracture of the discharge nozzle. Since all three lines shared the filtrate tanks, the failure drained one tank, shutting down all three lines and making a major mess in the wash room basement and all the way into the main maintenance shop. We replaced the casing and started again assuming that the casing was faulty. We notified the new vendor of the failure when we ordered a replacement spare casing. About a week later this failure was repeated on another of these pumps! Same results except no spare casing; had to retrofit one of the old ones and operate at a reduced rate until the new spare casing was delivered. Less than a month later…failure #3.
I pulled the O&M manual delivered with the pumps (found one stashed away in the pump repair shop! The other 11 copies delivered as required by the PO could not be found). On the front page of the installation section, it was clearly stated that the pumps could not support pipe stresses. Proper installation called for all piping to be totally supported prior to connection to the pump. In fact, the instructions were to align pump and motor with suction and discharge pipes disconnected, then connect piping. Recheck alignment. If alignment was then out of specification, disconnect piping, resupport piping, realign pump, reconnect piping, recheck alignment. This procedure was supposed to be repeated until connecting the piping did not effect the alignment.
In checking with the crews that installed the pumps and our guys who observed the procedures proved that this was not done. The pumps were installed, piping attached, and alignment completed. I shutdown one wash line, had alignments checked (all were within specs), disconnected all piping (some of the piping moved as much as 3”!), rechecked alignments (not one of the six pumps was within alignment specs. Through a combination of resetting piping supports, chain falls, and come-alongs, we were able to support all pipes so that no piping loads were applied to the pumps before we started-up. Over the next few days we did the same on the other two lines. No more casing nozzle failures!
Not only did we at UCC not read warranties, we didn’t review O&M manuals on most things.
This is only one example; there are others. But this one was a costly one in effect but cheap to resolve, once the O&M manual was consulted.
“Nip Impressions” always catches my eye and generally brings back memories. Thanks for the trips through yester-year.
Have a comment? Send your email to email@example.com. Unless you tell us otherwise, we will assume we can use your name if we publish your letter.
Remember, if you please, to let your suppliers know you read Nip Impressions!