Author Topic: Stuart Boiler Feed Pump  (Read 44568 times)

Offline Florian Eberhard

  • Full Member
  • ****
  • Posts: 400
Re: Stuart Boiler Feed Pump
« Reply #150 on: January 15, 2014, 08:45:27 AM »
I am guessing that you didn't take the video yesterday  ;)

Nope  ^-^

It was taken on monday the 6th of january.  ;)

Online Jo

  • Administrator
  • Full Member
  • *****
  • Posts: 11685
  • Hampshire, england.
Re: Stuart Boiler Feed Pump
« Reply #151 on: January 15, 2014, 09:02:09 AM »
 :o You made us wait a whole week to see it :(

Jo
Usus est optimum magister

Offline Florian Eberhard

  • Full Member
  • ****
  • Posts: 400
Re: Stuart Boiler Feed Pump
« Reply #152 on: January 15, 2014, 09:29:10 AM »
Yes! But it has nothing to do with MEM :embarassed:

There was the "Echtdampf Hallentreffen" in Karlsruhe (Germany) and I was waiting with the upload on youtube because a few guys from the german forums know my youtube account very well and they would have seen the movie before seeing the Pump (they had no Idea I was making this pump...)  ;)

Offline NickG

  • Global Moderator
  • Full Member
  • *****
  • Posts: 1426
Re: Stuart Boiler Feed Pump
« Reply #153 on: January 15, 2014, 06:52:37 PM »
Awesome stuff Florian, fantastic to see it working on steam and actually doing a job.  :ThumbsUp:

Offline K.B.C

  • Full Member
  • ****
  • Posts: 155
Re: Stuart Boiler Feed Pump
« Reply #154 on: January 16, 2014, 05:11:21 PM »
Hi Florian,

( quote from your post No 143 . 
Well, there was a "wait a second" in my head. Someone (here?) told me that silicone O-rings will expand under heat. In fact, the pump could only be moved hard, with quite an amount of force.
So I stopped the whole thing, took the pump back to the shop and removed that o-ring. Instead, I made a piston packing with teflon tape. )

I mentioned the Silicone ring some time ago that it expands 100% under steam.
You have used Black Viton rings that are not suitable for steam but Pneumatics and Hydraulics, so when the steam hits them they stick.
Also the groove dimensions that you use seam too tight if you were to use Silicone "O" rings.

I must commend you on your decision to make the pump slide valve rather than to the Stuart drawing, it has much more control without the amount of steam loss in the exhaust which is a bit of a pain in a Piston valve set up hence Stuart pumps are renowned for their steam consumption.
It would appear that the "O" rings on the shuttle is a good thing but can't be fitted to the Stuart drawing as they would pass over the steam ports and tear.

I finished my Pump a few weeks ago and it performs well being self starting and can be slowed down, I left out the drain valves as the pump clears itself of condensate every time on start up, the tapped holes for the drains are there with a plugs inserted to fit valves in the future if ever needed. 

Good job, well done !!!!!!!!!!
(Enclosed some pics of my completed pump)

George.
Your never too old to learn.

Offline Florian Eberhard

  • Full Member
  • ****
  • Posts: 400
Re: Stuart Boiler Feed Pump
« Reply #155 on: June 24, 2014, 07:23:03 PM »
Hi everyone

I am sorry that i've let you wait such a long time! I didn't do anything on the pump for a long time. But there is a good reason why:


I had to do the electronics for my milling machine. That means building up the ontrol cabinet for the frequency converter (1st picture)
Now my milling machine is "independent" and has its own speed controlling unit (2nd picture)

AND I had to do the same for the lathe, so you can imagine id did take some time to do this for both machines!

However, lets get back to the pump!

Next was building the cylinder cover:
I didnt like the anodized piece of aluminium sheet that was delievered by stuart. I thought it was much to thick to look good!
So I took some 0.1mm brass sheet. Though that is not as easy to machine as the aluminium sheet. I started with the metal shears and then milled the edges with the piece of sheet clamped between two pieces of wood.
After the cover had its exact dimensions, I made the little holes to fix it using a 1mm mill. (I was worrying about the sheet to be pulled up using a drill)
I then expanded the holes to 1.3mm using a drill, that worked quite good (after I tested it on a little waste piece) The screws inserted for a first impression.

Then I had to drill the center holes into the cylinder. I started with the row on one end, all the others were done with the pattern of the cover.
First using a center-drill to spot-drill, then continuing with the 1mm drill which is the center-bore for an M1.2 thread. The tape is used to hold the cover tight to the cylinder whilst drilling. I always had to position on one side of the cylinder and then could move the y-axis. That did work really well because I had drilled the cover-holes by coordinates.
Finally cutting the thread. I usually start the thread in the machine but then remove the workpiece from the vice so I can hold tap and workpiece in my hands as it is easier to control the amount of force you put on the tap.

To be continued right away (almost ;) )
« Last Edit: August 15, 2017, 09:25:35 PM by Florian Eberhard »

Offline Florian Eberhard

  • Full Member
  • ****
  • Posts: 400
Re: Stuart Boiler Feed Pump
« Reply #156 on: June 24, 2014, 07:37:20 PM »
After the screwholes, I had to make three big holes (8mm) for the exhaust and for the two drain cocks.
How I locate the exact position on the cover.
First I put a piece of round material with an according thread into the cylinder.
Then I rise the milling machine's table (with the vice on it) and move the table until the cylinder is just on the fixed jaw.
After clamping, I remove the piece of material and put the cover on the cylinder
Then I made three pilot holes with the center drill. And I had to repeat this procedure for the two other holes.
After removing the cover from the cylinder, I centered the pilot hole under the spindle using a "needle". You may notice the piece of wood held above. With the needle removed, the sheet is clamped with that piece of wood.

Finally, the holes are milled up very carefully with an 8mm endmill.
Three times drilled, three times a sucess (with such a thin piece of sheet...)

Then assembling it to see how it looks. Yes! Came out very nice!  :cheers:
« Last Edit: August 15, 2017, 09:30:13 PM by Florian Eberhard »

Offline Roger B

  • Full Member
  • *****
  • Posts: 3487
  • Switzerland
Re: Stuart Boiler Feed Pump
« Reply #157 on: June 24, 2014, 07:41:28 PM »
Glad you're back machining metal again  :ThumbsUp:  :ThumbsUp: That cover looks great  :praise2:
Best regards

Roger

Offline Florian Eberhard

  • Full Member
  • ****
  • Posts: 400
Re: Stuart Boiler Feed Pump
« Reply #158 on: June 24, 2014, 07:48:50 PM »
A job I was waiting with (for lack of an end mill which was wide enough): Plaining the bottom side of the pump base.
I also had to drill the holes to fix it to the ground. I drilled them from the upper side because the casting was not very good. And I wanted them to be more or less centered in those "ears" (How are they called??)
I also had to drill another hole for the valve rod stop-screw as well as making it and the counter-nut.

Finally, I replaced the teflon tape packing on the piston with a self-made glyd-ring.
To get the teflon-ring onto the piston, a tapered tool was required.
But after expanding, the piston ring doesn't want to get as small as it was before. So you also need some kind of a funnel to get the piston back into the cylinder:

That's it for the moment. I am waiting for some solution to blacken the cylinder cover. But mechanically the pump is finished now!  :jumpingsmileys:

Cheers Florian 
« Last Edit: August 15, 2017, 09:33:09 PM by Florian Eberhard »

Offline Roger B

  • Full Member
  • *****
  • Posts: 3487
  • Switzerland
Re: Stuart Boiler Feed Pump
« Reply #159 on: June 24, 2014, 08:21:23 PM »
For the fixing ears you could also use the term lugs (which is, however, also English slang for the ears on your head  :)  )
Best regards

Roger

Offline Dave Otto

  • Full Member
  • *****
  • Posts: 3354
  • Boise, Idaho USA
    • Photo Bucket
Re: Stuart Boiler Feed Pump
« Reply #160 on: June 25, 2014, 01:13:15 AM »
Nice work Florian,

Good to see you back at it!


Dave

Offline derekwarner_decoy

  • Full Member
  • ****
  • Posts: 414
  • Wollongong ...... Australia
Re: Stuart Boiler Feed Pump
« Reply #161 on: June 25, 2014, 02:21:59 AM »
Florian........

1. your sizing & resizing tools are perfect to the application for the installation of the Busak style piston Glyd ring........
2. I have never seen the use of two o-ring energisers under the one piston seal, certainly Hallite, Merkel, nor Frudenberg nominate such use....having said this.....I see no reason why this should be an issue
3. because the TEFLON material has such poor memory qualities, we place the Glyd ring in boiling water + a few tea spoons of sugar....then microwave  :Mad: for a short period....this actually increases the boiling point of the water by say 5 to 8%
4. this then provides greater elasticity of the TEFLON & less potential for permanent deformation or stretch prior to the resizing process
5. the reason for this is the TEFLON cools quickly when in contact with metal

Derek
Derek Warner - Honorary Secretary [Retired]
Illawarra Live Steamers Co-op - Australia
www.ils.org.au

Offline Florian Eberhard

  • Full Member
  • ****
  • Posts: 400
Re: Stuart Boiler Feed Pump
« Reply #162 on: June 25, 2014, 07:38:46 AM »
Hi Derek

The Reason for using two o-rings instead of one is just laziness. This way, I didnt have to modify the groove in the piston.

Florian