Steam Department

This was a big day at the steam shop.  All activity was focused on 1630 and the first testing of the boiler completely full of water and under some pressure.

It is a fairly lengthy process to set the boiler up for pressure testing.  The boiler and water need to be fairly warm (about 100 F) for testing.  So aside, from pumping 2500 gallons of water from the milk car to the boiler, there is about 5 hours of circulating the water thru the gas fired pool heater to bring the whole system up to an even temperature.

Starting in the morning it was late afternoon before the whole system was at temperature.  During that time we spotted and corrected minor leaks around the inspection and dome covers. 

Refitting the inspection cover

Removing the dome cover to fix the seal gave this interesting shot into the open dome.  The boiler is now about as full of water as it can be.

Just about as full as can be

With everything sealed we started to apply pressure to check for leaks.  In general, we were fairly pleased with the way that the work we have done stood up to pressure.  There were maybe 20 small to tiny leaks disclosed around tube ends.  In retrospect one mistake was that we did not fix leaks around two super heater flues in the front tube sheet.  These were very small sources of drips under gravity but became the limiting factor when we reached 150 psi. 

The firebox patch was tight aside from a small spot in the caulked joint with the mud ring which showed a slight leak at 150 psi.  This should be easily fixed by a little more caulking.  A couple of rivets close to the patch showed signs of weeping.  This is not surprising given the expansion and contraction associated with the welding and can be fixed by a little work with the caulking hammer.

The nuisance and minor setback was an area that we had not worked on.  We found tiny pinhole cracks in the sockets of two flexible stays in the back head.  These may have been there when she last ran as they are so small that we would probably not have seen any leakage from under the lagging and jacket.  Certainly they would not have caused any loss of pressure in the hydro-testing. 

However, knowing that they are cracked, even a pinhole, they must be replaced.  This involves grinding off the inner end of the stay and, after heating the end of the stay, trying to unscrew the stay from the socket.  If this fails you have the much more time consuming job of drilling out the stay at the inner end.  However, it worked well.  By Saturday evening both stay bolts were out, without the need to drill either.  In this view you can see the empty sockets after the stays were removed.

Stays removed from the problem sockets

On Sunday I started cutting one of the sockets off from the back head and, in the afternoon, Mike and Tom completed the job.  So both of the sockets shown above are now gone and we are ready to fit the new sockets.  Tom will then need to drill and thread two new stay bolts so they can be refitted.  This will mean no pressure testing next weekend but hopefully all will be back and the leaks fixed by 8/10.

On this basis, I met with the FRA inspector on site Sunday and we scheduled the formal hydro test for 8/18, subject to a successful second stage test for leaks the previous weekend.

Just about all effort was concentrated on 1630.  However, a big event was that both Bill Chyna and Glenn Parkhurst visited.  Glenn for the first time since his motor cycle accident in May.  Glad to say they were both in good form and Glenn is hoping to be able to join us again when he has his prostheses fitted in the next few months.

Bill and Glenn visit the shop

I am heading for the UK on business this week and will not be around the shop next weekend.  So I am hoping to see a lot of progress when I get back in two weeks time !.

Nigel