Tender Handpump connection

[peterseager]

What do you guys reckon to be the best way of connecting the handpump line from the tender to the engine?

To give it a bit of context the loco in question is a 5"G Manor and there is 5/16" male thread on the engine for a union. Should I use rubber or copper for the plumbing and how do I arrange it to give some compliance. All the books give conflicting advise. What works?

Peter

[albert]

Hello Peter,
It has to be rubber/plastic to achieve flexability--will it be for gravity or pressure use?
Albert

[alanstepney]

As the handpump line is under pressure, the usual way is to keep to copper, and make two mulit-turns, one each end of the pipe.
That will give flexibility without binding at any position of the tender-loco, and allow for the pressure, which will, of course, be boiler pressure+.

[mutley]

Or sue one of the quick connect couplings. Blackgats and Polly both supply kits for connecting tenders with quick connect couplings and rubber hose.

Andy

[peterseager]

Thanks for the responses.

As Alan noted it has to withstand boiler pressure.

I was thinking of rubber, I happened to have some tube removed from a tyre inflater, but one book warned about hot water getting into it and reducing its life. The other problem I could see was lack of fore and aft compliance. But as Andy points out quick disconnect kits are available and these include a stiff rubber pipe. Do they work? Does one still put at least one copper coil after the rubber to get more fore and aft compliance?

I assume Alan's solution using copper tube means one coil just behind the tender drag beam and another at the back where the pipe exits the tank from the pump, otherwise in a straight line. I also assume Alan it talking of flat coils like this:

--O----------------O---

One author suggested putting a coil with its axis on the axis of the pipe. A sort of tension spring arrangement:

-----WW------

This seems to have some merit if it can be fitted in the space.

Whats has worked for you?

Peter

[Tony K]

Feb 13, 2010 21:45:14 GMT peterseager said:

I was thinking of rubber, I happened to have some tube removed from a tyre inflater, but one book warned about hot water getting into it and reducing its life. Peter

Do not knock the tyre inflator. Good old LBSC used a bicycle pump connection for his Netta (on the drawings). I have the 3½" version with it on. It works, but not as convenient as the snap-on connectors, since it has to be a nut connection. You have to change it every 5 years - so what?

One of the kits would do it for me - nice snap-on connectors really work well - and look professional, if not authentic.

[jonkett]

If using coil of copper tubing, wouldn't you need two, one in the vertical plane and horizontal?

[steam4ian]

G'day all

In terms of high pressure "rubber" tubing. These days with fuel injected cars high pressure fuel hose is available. Common rail auto diesels probably use the same stuff.

Regards
Ian

[teakfreak]

The tube may have to stand boiler pressure, but it shuldn't reach boiler temperature. THickwall pvs tubing out to do fine. I've done my Sweet Pea engine-tender hoses this way. Put 5/16 x 32 (or whatever size suits you) female unions on the engine and tender and corresponding male unions on the "bag" . Aanother union cone on the end that the plastic pipe slips over gives something to grip against with securing cable ties. The unions are easy to connect and disconnect - I allow for a coil of extra tube to give flexibiity on curves. The plastic pipe itself is dirt cheap.

[JDEng]

Industrial air-lines are often done in PVC tubing of the type that has a cord matrix around it within the plastic; they withstand 80 to 100psi 24 hours a day in some applications with no bother at all. I would have thought you'd be fine doing it in that; it's easily and cheaply available.

John.

[durhambuilder]

A nice braided stainless steel flexible brake pipe would look quite neat and no problems with pressure. Thinking about it the tube will only be at boiler pressure whilst actually pumping, the rest of the time the boiler clack valve will ensure there is no pressure in the pipe.