Model Engine Maker

Supporting => Engine Ancillaries => Topic started by: sbwhart on July 20, 2012, 08:16:36 AM

Title: Simplex Locomotive Boiler Feed Pump
Post by: sbwhart on July 20, 2012, 08:16:36 AM
This is the boiler feed pump I've been making for the Simplex Loco I'm finishing off. Its to the improved super simplex design that has larger feed galeries and a different arrangment of return valves making it more compact, it's a double acting pump.

Drilling the and tapping the body

(http://i431.photobucket.com/albums/qq32/sbwhart/131_1776.jpg)

Measuring the height of the ball valve

(http://i431.photobucket.com/albums/qq32/sbwhart/Simplex/131_1854.jpg)

Setting the ball down onto the seating by giving it a sharp square biff.

(http://i431.photobucket.com/albums/qq32/sbwhart/Simplex/131_1855.jpg)

The parts off the pump exploded out.

(http://i431.photobucket.com/albums/qq32/sbwhart/Simplex/131_1858.jpg)

I still need to fix the pump into the loco frame.

This is the eccentric where it has to be linked to.

(http://i431.photobucket.com/albums/qq32/sbwhart/131_1787.jpg)

Stand by for updates

Stew
Title: Re: Simplex Locomotive Boiler Feed Pump
Post by: Alan Haisley on July 20, 2012, 09:47:13 PM
Stew,

If you needed to mount the pump other than vertical, would it be enough to simply add springs to the balls or would more need to be done  :-\

Alan
Title: Re: Simplex Locomotive Boiler Feed Pump
Post by: sbwhart on July 20, 2012, 10:13:48 PM
Hi Alan

Regardless which way the pump is mounted springs are not required its the flow of the water (pressure) that closes the balls onto the seats and cuts of the flow, when the piston changes direction it sucks lifting the ball off the seat and allowing the water to flow round it, to fill the chamber ready for the next power stroke. i can send you a copy of the drawings so you can see how it works.

Thanks for you're interest.

Stew
Title: Re: Simplex Locomotive Boiler Feed Pump
Post by: Alan Haisley on July 22, 2012, 03:40:42 PM
I hadn't considered the speed that the piston would be moving the fluid. I've been thinking about making a small vacuum/pressure pump and had just assumed that the check valves would need to be spring loaded. In hindsight building without springs has two advantages: simplicity and not scratching the balls with the spring wire (I assume that not all purchased steel balls are hardened the same).

Alan
Title: Re: Simplex Locomotive Boiler Feed Pump
Post by: sbwhart on July 30, 2012, 09:02:19 AM
A bit of an update more or less got the pump completed just needs the packing added i'll do that when I do the final assembly.

I had to make a new streacher to mount eh pump in the frame.

Here it is with the pump fitted.

(http://i431.photobucket.com/albums/qq32/sbwhart/Simplex/131_1916.jpg)

Stew
Title: Re: Simplex Locomotive Boiler Feed Pump
Post by: steamer on August 05, 2012, 10:57:07 AM
Like that pump a lot Stew!

My boat is still in her cacoon from last winter :facepalm:

I want a bit better performance from the engine driven pump.....so I'll watch along and copy if you don't mind.

Dave

Title: Re: Simplex Locomotive Boiler Feed Pump
Post by: sbwhart on August 05, 2012, 11:01:13 AM
Dave

Made a feed pump for a friends boat last year.

This is O9L6g-mafvo
Build log over on madmodder

http://madmodder.net/index.php/topic,4763.msg53093.html#msg53093

Stew
Title: Re: Simplex Locomotive Boiler Feed Pump
Post by: steamer on August 05, 2012, 11:10:03 AM
Thanks for that Stew!   I'll probably take you up on that! 

I've run a lever driven pump on my engine, but it can't cope with a blower......having this on a throttle or a float from the hot well would help a lot!

Dave