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[Landlocked]

Beautiful work.  I like the piping supports.  How are they made?  I trust there's a rubber layer to prevent the metal to metal that would create a "heat transfer short" and negate the wonderful insulation work you've done?


Ken

[derekwarner]

Thanks for the comments guys ...... the tubing supports are simply 1/8" tube size Dubro brass collars..+ a 10 mm long x 5 mm hex brass stand off from an electronics shop [these are tapped M3] so the supports are secured from under the tray.....oh & a short length of 2.5 mm brass tube soft soldered between the two.....the only bit of rubber is the nitrile o-ring between the flange halves.....

The 300 mm long lower tube is for the boiler make up water...... Derek

[southsteyne2]

Nice job Derek 
Just curious about the long   "water feed" pipe that appears to be connected to the water gauge am I missing something as I don't see a need for it except to turn the water overboard through a hull fitting.
Cheers
John

[derekwarner]

Hi John....bad camera angle on my part 

The 1/8"OD make up water line enters the boiler via an isolation valve @ an upper tapping [above the water line in the boiler]
I hope to have approx. 1 litre of make up water up FWD to be pumped [with additional check valves] as required into the boiler
Have used a 4 port plug valve [from e-bay for $11.00 including air parcel post] for the water distribution ...[2 for pumps...& 2 for drains?]
The boiler pressure pilot signal for the gas regulator is another tapping pre installed in the boiler but at a lower level......
The Scottish boiler as manufactured did not have a gauge glass  blow down facility...in retrospect I should have asked for it  ....Derek 

[southsteyne2]

No problems Derek I see it now will be very interesting to see in operation
Cheers
John

[ballastanksian]

Crikey, that set up looks as complex as the real thing:O)

[xrad]

Very Nice work!  So you are sticking with the microcosm pump/pillow block set-up. I just could never get mine to out-put enough water at enough pressure.  Did you test it with a pressue gauge?
 
 

[derekwarner]

Evening xrad.......things have changed & I have installed a shaft driven M5 pump & an electric drive auxiliary M5 pump....but to answer your question.........

1. no I have not yet trailed the system yet
2. the simple o-ring on the piston must be able to achieve greater than 10 Bar
3. the displacement  = volume x RPM ......... ....I suspect  may not obey the Laws of physics....hence the additional auxiliary pump

Will keep the WEB thread posted .....Derek

[hammer]

Derek, You know I know nothing when it comes to theory. BUT if your boiler is operating at 10 Bar that is per square inch I presume? Well if your delivery pipe also has an area of one square inch then the O ring will in deed have to withstand 10 Bar. Don't you need divide the area of pipe into one square inch?  Hammer a.k.a  R.G.Y.

[derekwarner]

 ...morning RGY...... ...I was using 10 Bar as an example only.....O-rings in simple dynamic applications are fine for 100 Bar.........but really need an anti extrusion back up ring at these pressures

My ACS boiler relief valve setting is 3 Bar [45 PSI] so that is all that the piston pumps are expected to produce to replenish the boiler water

As always.....nice to hear from you....how are your chooks?....... ....Derek

[southsteyne2]

H Derek I think you are setting yourself up for future headaches as you only need the slightest air leak and any pump is out of action.
I have just built a engine feed pump to George ooya2 design with direct feed to the boiler and very little loss of power only 1 clack valve also there is no "o" ring on the piston ram ,the seal being on the pump body ,pumps a bit more than the boiler uses powering my single cylinder 5/8th bore 3/4 stroke but a few blasts on the whistle will balance it out but haven't tried it on the water yet so hoping I like to keep things simple in model work as it helps to ensure a happy outing sailing 

[derekwarner]

Thanks John......I had read good reports [Jerry C] of the boiler feed pump by George [ooya2] but was not privy to the actual design

Placing the seal into the gland reconfigures the design to be a displacement ram, whereas placing the seal on the piston is just a piston with a seal and no gland seal required

In each variant, the seal is dynamic & subjected to the same loadings & velocity....the larger size gland seal sealing on the ID & the smaller piston seal sealing on the OD

With the o-ring being pressure energised.......I sincerely hope the will be no air in the system.......Derek

[hammer]

Derek your far more educated than me. It is true the pump in your example will need to push at 45 P.S.I.  Here is the but, as I said before you need to divide the area of the delivery valve into 1 square inch. This will be the pressure required from the pump NOT 45lb. I can't work it out, I am just a poor old chippy. I am sure you can. let me know please.  RGY   

[derekwarner]

RGY....when the chips are down.....wisdom & experience equals or betters education every time .......however today we blame that French guy Mr Pascal  .......extract from Wiki as follows......

Pascal's law or the principle of transmission of fluid-pressure is a principle in fluid mechanics that states that pressure exerted anywhere in a confined incompressible fluid is transmitted equally in all directions throughout the fluid such that the pressure variations (initial differences) remain the same.[1] The law was established by French mathematician Blaise Pascal.

Think of your hydraulic car jack.......it may be rated at 5 tonne........but the plunger piston may be only 10 mm diameter...just means more strokes of the 10 mm diameter piston to exert the required pressure on the larger jack piston to achieve the effort

PS...I will send a PM........about a vessel 200 km north west of Hamburg.......Derek

[hammer]

 Derek PM not getting through? Missing a full stop (dot) between first & family names. My post keep coming back as well.  It is robert. R.G.Y.

[derekwarner]

mmmm  a little more tube work but best left un-lagged I think  ................ Derek

two pump suctions
one drain  ...it appears out of square on the horizontal & the plan perspective............ ......but no ....its just the camera angle 
one pump bypass

[hammer]

Derek they say the camera doesn't lie. But that is the lie. Hammer

[derekwarner]

Good morning RGY......

Here is another image that confirms the camera can distort things.....[the drain line is the lower tube..... ...or 3rd to the left on the manifold]

BTW....how are the chooks? 

Derek