Steam Department

A good day of progress on a number of fronts.

On 1630

·         Success at last on the swager.  Tom spent much of last Sunday honing the damaged bores in the dies.  We spent most of the morning carefully refitting and aligning them in the machine but it looks like we have success.  Several old tubes were successfully swaged and the machine operated smoothly throughout.  Now we are ready to go into production.  Having gone thru the set up the objective will be to do the tubes for both 1630 and the Shay so between 400 and 500 tubes in total.  The current major problem is that all the tubes are in the boxcars and the diesel guys were not able to switch these before the snow arrived.  So we are now dependent upon a break in the weather to allow the boxcars to be switched to a position where we can move the large bunches of tubes to and from the shop.

What does swaging achieve?.  The tubes of a steam locomotive boiler are expanded by rollers into the tube sheets to make the seal.  Commonly the tube diameter in the firebox tube sheet is smaller than the general diameter of the tube.  This is a crafty piece of steam locomotive design.  For efficiency you want as much tube area as you can achieve in contact with the water.  The hottest, and therefore most stressed tube sheet, is the firebox end.  So narrowing a couple of inches of the tube where it runs into this tube sheet allows more metal to remain in the tube sheet between the holes.  So on 1630 (and the Shay) the tubes are 2 inch diameter but are shrunk by swaging to 1 7/8 at the firebox end.

The objective of the whole process can now be seen in one of the test tubes.

A swaged tube looks like this

The process is first to heat the end in a furnace

Into the furnace

then hammer it between the dies, that we have had so much fun with, for about 15 seconds turning it as it is hammered so that you get a nice even 1 7/8 inch tube end.

The swager finally working

·         The dome cover was successfully removed to allow lapping of the throttle valve which is one of the key repairs to be carried out.  The fork lift made life a great deal easier as the cover could slid directly onto the forks and brought down to the ground.

Just slide it sounds easy!

The forklift makes this a lot easier

At ground level you can see how big and heavy it is

·         It is now clear that we have 4 or 5 stays on the back head where the sleeves are sufficiently worn to need replacing so that will start soon.

·         Mike continued with grinding out the rivet and patch bolt holes to enable fitting of the firebox corner patch.

On 428 an number of machining jobs were progressed

·         Bob and others continued honing the coupling rods to allow new bushes to be fitted;

·         Stu and Cameron continued with the packing glands; and

·         Tom and Cameron worked on the set up of a large piece for horizontal drilling.  (Looked very impressive but I did not like to disturb the efforts by querying exactly what it was!).

Around the shop Jeff continued the program to free up more working areas.

·         The space is now ready to safe end the super heater flues for 1630 which are coming back from sandblasting in the next week or so;

·         Some unused machines were moved out of the machine shop which will enable a really challenging move of a large turret lathe from the wheel lathe area to the machine shop.  This will allow the turret lathe to be activated and enable wheels to be stored away from the door and overhead crane;

·         We also lifted the McCabe flanger so that it can be properly mounted on timbers that will allow it to be moved.  This will free up space to handle large numbers of tubes that are to be swaged.

So another productive weekend.

Nigel