Regulator

Hi

Has anyone made and is using a Gordon Smith ball and spring type steam regulator

David

>bump<

What type of regulator does anyone use, disc Stoudley type, disc in a tube, needle valve in a tube and what are the merits and advantages or disadvantages of each type.

David

My favourite is the screw (needle valve) type, preferably with a PTFE type material for the seat. Seals 100% and a nice smooth and gradual opening. Made quite a few and never had any problems with them.

I personally hate any rotating disc type regulator as it's virtually impossible to get them to seal against a hydraulic test and not easy to get them to seal against ordinary steam pressure.

John

I'll go along with John on this.

I have a 2.5" GNR Atlantic (reputedly built by Peter Dupen and his brother before the war) and it has a disk-type regulator that is giving me grief. As a 'vintage' engine - I don't want to do too much to alter it but I've been very tempted to do so.

Regards,

IanT

PS It's a disk in a tube type by the way...

Edited By IanT on 26/03/2015 15:42:34

I use plumber ball valves - very cheap and reliable

Hi guys, thanks for the replies.

John could I ask how far you have to rotate the spindle to get a reasonable flow, I expect you are using a coarse thread.

David

Hi David,

I use the largest diameter Whitworth thread that I can fit in. I find that 1/8 to 1/4 of a turn gives ample opening for normal running. It's surprising how little an opening of the regulator you actually need.

John

Here's one I made for my 2½" gauge Helen Long:

If I remember correctly, the thread on that is 3/8" Whit. The seat is bearing grade PEEK which contains PTFE and Graphite. The spring was supposed to take up any backlash in the thread but proved to be unnecessary,

I made a couple of smaller ones for two Tich's that used 5/16" Whit threads.

As Fizzy says though, ball (gas) valves are very good if you have the room to fit one. Just make sure it is rated for the pressure and the temperature.

John

Edited By John Baguley on 27/03/2015 00:36:50

Could John Baguley be persuaded to post drawing of his Tich regulator, save me dreaming up my own?

My little Tich has the same type of regulator as John Baguley's posting shows above. It's been what must be getting close to 30 years now since I made it, and it has been problem-free.

I believe that the thread was 1/4-20 UNC, and the end of the spindle was about a 45 degree taper, but that's from memory. The 1/4-20 thread was the coursest thread I could find in my taps and die collection.

The regulator has been problem free.

Just another thumbs up for that design.

Hi guys

Thanks for the postings, all very good information, one question I have if anyone can answer it is the quantity of steam I could pass through one of that design. I am building a 3 cylinder 5" gauge Royal Scot, Martin Evans design, the regulator he shows is a sliding plate on the top of the regulator body, the body is shown with 2 x 5/16 holes so my concern is whether I could get sufficient steam through a screw type regulator.

2 off 5/16 holes is huge, you will get away with a lot less

http://www.engineeringtoolbox.com/flow-velocity-steam-pipes-d_386.html gives recommended speed for high pressure saturated steam, work it out from there.