Reply To: Engine 1000, or other Yarrow like designs – has there ever been a model?

[Richard ParsonsParticipant @richardparsons61721]

At last I have found some pictures I can copy for you. They ate at http://www.vlaki.info/forum/viewtopic.php?f=2&t=3662&start=60 which is in German and http://erojr.home.cern.ch/erojr/Content/phylo/BROTAN.HTM which is in English

As you will see the firebox contained the Yarrow type water tube which fed steam into a separate collector. On the original Botran boilers the separate steam collector fed into a standard fire tube boiler; this it in turn fed water into the Yarrow fire tube system in the fire box.

The Brotan-Defner boiler was a modification of the original Botron, but here the steam reservoir was connected directly into the main fire tube boiler. This made the boiler rather tall
There are a few models in the Budapest Transport Museum but weather they work or not i have no idea.

Hungarian Botran-Deffner

 

A Baldwin 60,000 boiler