Help please Black 5 Super Heater

I need to make my super heater but the plans miss some vital information.

It shows a threaded part that screws into the Boiler.

It does not show the other part that obviously bolts to that with pipes that than go where.

It does show the pipe for wet header and dry header.

What i need to know is where the 8 tubes will go from inside the Boiler and connect to what and where the feed from the Boiler and how many pipes go into it.

On the drawing it just shows a diagram of two pipes coming dawn from wett header 7/16 tube into an 1/2 wet header with 4 tubes.

Their is nothing showing where any connect to i am at a complete loss trying to figure out how they go can any one spread any light please.

Ron

Well after going to the club Sunday still don't understand how they work.

I have worked how the pipes go with just 4 straight pipes going into the Smoke box.

How can they work without a return surly they need a flow through to work.

My last Loco had two pipes going down each tube joined and one end to the header and the other going to Piston's witch to meet seems logical.

Am i missing how this works or like those that have been trying to help me got it totally wrong.

Ron

Hi Ron,

The B5 superheaters are what is known as coaxial type. They consist of a 1/2" diameter stainless outer tube with a 5/16" diameter copper tube running down the middle. The outer tube is blanked off at the firebox end and the copper tube doesn't quite reach the end. The steam from the wet header travels down the stainless outer tube and returns up the inner copper tube to the dry header.

Frankly, the coaxial type of superheaters are not very efficient and you would do better replacing them with the conventional type with two separate tubes jojned at the firebox end, the sort you are used to. Extend them over the fire right to the back of the firebox and you will get superheat worth having.

Here's a cross section of a coaxial type that I drew up in 3D for Neville Evans's Didcot that I've got all the castings for.

This is slightly different in that the end of the inner copper tube is supported by the blanking plug in the end of the outer stainless tube and the steam enters via a slot in the end. I won't be fitting one of these but the normal two element type instead.

John

Edited By John Baguley on 20/07/2015 18:20:29

Thank you John i just could not get my head round a pipe in a pipe i am sure i will use the two pipes the conventional way do you have one tube going from dry header then returning into the wet header so you get a proper flow

Ron

As a Novice trying to understand the Drawing i found impossible to John told me how they worked big thank you John

If only i was an engineer i could possibly work these out but i am not i am going to use conventional ones where two go down one tube and return in Stainless going over the fire Box.

My only question now is do i start with one pipe coming of the dry header then returning to wet header so i get the flow

Ron,

Yes, one side of the superheater comes out of the header on the front tubeplate and the return goes into the dry header that feeds the cylinders.

If you can, TIG weld the joint in the firebox, but if not, something like Silverflo20 or 24 will be ok. Silverflo55 is fine for the smokebox ends.

John

Thank you John i can crack on and make them now.

Yes i have a tig so that should not be a problem now i understand what i must do.

I just could not see how the others would work just did not make sense to me.

Another job i can tackle now.

Ron