tube or rolled?

[mark sandersParticipant @marksanders85565]

whilst looking at model steam boilers and you tube videos, i noticed in every case that i could see, that boilers always seem to be made from extruded tube and none shown to be rolled plate and soldered,brazed or welded. is this convenience on the part of constructors/designers or is rolling flat plate not allowed ?

[mark sandersParticipant @marksanders85565]

[Simon CollierParticipant @simoncollier74340]

Rolling plate is essential if you want a tapered barrel or if you can't obtain the size tube you want. Obviously using tube is easier. When rolling and joining with a butt strap, the required size of strap and spacing of rivets are specified in the Australian code.

[mark sandersParticipant @marksanders85565]

thanks for that, simon

[JasonBModerator @jasonb]

usually done for ease of construction, less work and one less joint to be made. Also I doubt most of the boilers on YT are that big or for scale models where you get less choice in availbale tube sizes so may have to roll your own.

On other deciding factor is that when doing the boiler calculations you have to make an allowance for a joint in the barrel as there is potential weakness so may well have to use a thicker and therefore more costly copper sheet.

Properly designed rolled and joined barrels are acceptable.

Edited By JasonB on 13/02/2018 07:31:49

[Paul LousickParticipant @paullousick59116]

The AMBSC code for Australian model steel boilers specifies seamless or welded pipe. Flat rolled plate can also be used and joined with full penetration butt weld. Not sure about copper boilers.

New and replacement boilers for full size engines are normally welded.

Paul.

[mark sandersParticipant @marksanders85565]

thankyou to Jason and Paul, i will take all that onboard

mark

[Author]

Posts