Achillies axle pump detail

[Alan]

Hi
Can anybody tell me the bore size and the stroke of an Achillies is please. I know its a twin pump, and I also know its been modified in its lifetime and I want to bring it back to standard or a more useable size.

Thanks

Alan

[Alan]

Hi

I think Ajax is the same. Any ideas yet please.

Alan

[Roger]

If you look here and hover over the picture, it looks like it says 3/8" bore. I can't find a drawing of the eccentric though

[ejparrott]

Looking at it I'd say eccentric with an absolute maximum of 3/8" throw

[Alan]

The Reeves drawing says 3/8" which is a good start. I would like to think it would have a bigger throw than 3/8th. Might be enough as their are two pumps.

I know our club Achillies has far bigger pump dias and a much greater throw, but that, I think is where the problem starts. Too many people with too many ideas and nobody checked back to the drawing to see what it was designed with.

1/2 way there. Thanks for the help so far.

Alan

[Roger]

I've gathered data from the people I know with axle pumps fitted to their 5" gauge locomotive and these are the results.

Butch has a double acting pump of 1/2" bore and 1/4" stroke so equivalent to 1/2" bore and 1/2" stroke. (12.7 x 12.7 / 4 x pi x 12.7 / 1000 = 1.609ml)

Hunslet drawing has 3/8” Bore and 5/8” Stroke, which is what they will change it to. (9.525 x 9.525 /4 x pi x 15.875 / 1000 = 1.131ml)

Hunslet when I drove it had 3/8” Bore and 1/2” Stroke, they will change it because they say it only just copes now. (9.525 x 9.525 /4 x pi x 12.7 / 1000 = 0.905ml)


MOK has 1/2” bore and 15/16” stroke but it's miles too big.

SPEEDY has 1/2" bore and 7/8" stroke so . (12.7 x 12.7 / 4 x pi x 22.225 / 1000 = 2.815 ml)

My modified version 1 has 10mm bore and 14mm stroke (10 x 10 / 4 x pi x 14 / 1000 = 1.1ml)

My analysis of this is that you need at least 1ml per revolution if that's any help.

[Alan]

Thanks again for the replies. next step for me is to turn her upside-down and see what I have on the bores. The eccentric looks so wrong in its extended throw

Alan