Swaging boiler
Posted by:
ianc (IP Logged)
Date: May 29, 2010 12:54AM
I know there are at least three more folks on this Forum who are having varying degrees of success in swaging a leaking boiler, so I thought I'd post this progress report. (You can read about my trials and tribulations in other posts.)
I got a call from a boiler-maker who had heard about my problems from a mutual friend. This fellow worked mostly on Canadian navy vessels, many of which had steam turbines and steam ancillaries. His advice was as follows: "If the boiler is not pinned (the sheets attached to one another in the centre, either by welded tubes or bolts) the boiler should be empty when swaging. 40 litres of water is 40 kg, which might be enough to distort the bottom crown. Secondly, although swaging in a pattern,a section at a time,is more work and needs careful attention to avoid missing tubes, it's more reliable. If swaging row by row doesn't work, try dividing the sheet into quarters, or better, sixths or eighths, and doing one section at a time, from the centre out."
Following that advice, my boiler now goes to 600 psi (water) with no leaks, drips, or weeps. Tomorrow, fire.
(Oh, and he advised firing it gently, one minute on, ten off, two on, ten off, etc., given my burner, which, he said, "Sounds way too hot for a little boiler like that. Whoever designed it must have really known what they were doing, if it works as well as you say it does.")
Wish me luck.