johnsmachines

machines which I have made, am making, or intend to make, and some other stuff. If you find this site interesting, please leave a comment. I read every comment and respond to most. n.b. There is a list of my first 800 posts in my post of 17 June 2021, titled "800 Posts"

Tag: steam valves

January 15, 2017

Assembling the Triple

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I got this far in assembling the model triple expansion steam engine, then lost courage and put it aside (again).  You can see the high pressure steam chest labelled “top”, the steam valve and handle, the drag links and levers for the reversing mechanism for the high pressure cylinder, and the worm and gear and control wheel for the reversing mechanism.   The reversing levers will need pinning with taper pins when the correct positions are finalised.  The short rod in the middle of the pic is temporary.  I need to make those properly.  The drag links clash with the condenser cover.  That was predicted in Bertinat’s notes.  The cover will need some material removed.  Slowly progressing, but taking frequent breathers.

The high pressure mechanisms are the most exposed, and easiest to access, and they were very tricky, and not yet compeletely installed.  I dread to consider what the intermediate pressure ones will be like, buried in the middle of the engine.   Then there is the valve timing.  Help!

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January 2, 2017

SS Valve Rods

Making the new valve rods, as predicted, took me an entire day.  They required a high degree of precision, and being in stainless steel, not an easy material to machine, and quite thin and delicate, multiple stages in the machining.

But before I started on the valve rods I made myself a new spanner for the collet chuck on the CNC lathe.  I had been using an adjusting spanner, which was continually  going out of adjustment and causing angst.  The tool merchants did not have anything suitable (46mm opening, and thin profile), so I made my own.

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The 46mm spanner being cut from 6mm steel plate.

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It is a bit prettier after this photo and being painted.  The rounded jaws facilitate easy application to the collet chuck.

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Tightening the ER40 collet chuck with the new spanner.  It works very well.

So then I got on with the new valve rods.  Some end of day photos follow.

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The valve rod is the silver coloured rod.  Actually stainless steel.  This photo shows the high pressure cylinder valve and valve chest.  There are 2 other valves, one for each cylinder.  All different sizes.

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The high pressure valve chest and valve, the valve rod and guide.  On the right is the Stevenson’s link, yokes and eccentrics which control forward and reverse.  This setup is repeated for each of the 3 cylinders.  This is hooked upto the worm and gear which was shown a blog or two ago.  There are 22 components for each, not counting fasteners.

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The low pressure setup.

And thank you to those readers who responded to my whinge about likes and comments.  I will continue this blog until the triple expansion steam engine is finished, and hopefully running.  Not sure after that.

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