Richard J. Smith Boiler


One of the later designs of a Richard J. Smith boiler.  It has two helical coils of black iron tubing with the outer one being a water wall tight wound and the inner one using welding rod pieces to space the coils.  The entire center is the combustion chamber.  Hot gases pass between the spaced inner coil and past the outer water wall before exhausting.  The entire tube bundle is used to expand and contract for boiler control.  We are pretty sure that this is not an efficient boiler because there is not pure counter-flow.  It would do well with an economizer added to the stack.  This unit was designed to power a 99 c.i.d.  Mercury outboard bump valve conversion steam engine.   Richard J. Smith