47 Deland Ave. Columbus, Ohio 43214
Last summer we were so fortunate as to become the owner of the
ancient Greene steam engine that powered the Cheraw Sash Door and
Lumber Co. of Cheraw, South Carolina for many years. After two long
truck trips over the mountains and some on-the-scene ‘head
scratching’ over how to get the ten-foot flywheel up out of its
accompanying picture shows the frame in storage awaiting
restoration at Trail Run Station, Monroe County, Ohio.
The Greene engine was patented in 1855 by Mr. Noble T. Greene,
six years after George Corliss received his basic patents. Like the
Corliss, it has a drop cut-off valve gear with dashpots, and the
separate inlet and exhuast valves are located at the four corners
of the cylinder. There the similarity ends, however, as the valves
are of the flat ‘gridiron’ type and the arrangement of the
mechanism that works them is entirely different. The inlet valves
are tripped by a ‘plug-tree’ mechanism similar to that used
on the early Newcomen and Cornish engines. An eccentric on the
crankshaft works a slide on the side of the cylinder through the
usual reciprocating rods. To open the valves, lugs projecting from
the top of the slide engage fingers hanging from the ends of the
two rock shafts running to the upper part of the cylinder. As the
slide continues it motion, the ends of the fingers are swung up
until they slip off the lugs, allowing the valves to snap shut. In
the Greene, the governor varies the height of the lugs to control
the point of cut-off. Unlike the single-eccentric Corliss engine,
it can cut off at any point from the beginning of the stroke to
nearly full stroke.
The exhaust valves slide crosswise under the cylinder and are
driven by an oscillating side shaft from a second eccentric.
Mr. Corliss brought suit and managed to halt production of the
Greene engine for a time, but its manufacture was resumed at the
expiration of the Corliss patents and was continued for several
years by the Providence, R.I. Another example is on display in the
Ford Museum.
While in Cheraw we viewed an even larger steam engine in another
factory there. It was a Murray Corliss, with twelve foot flywheel.
A relatively plain engine and with quite a bit of rust damage, but
it could be restored if anybody wants a big engine badly
enough.