Improvements in Stuffing-boxes for Steam-engine Cylinders and other Apparatus.
Year: 1889

page_text: Date of Application, 20th Dec., 1889
Complete Specification Left, 18th Sept., 1890-Accepted, 1st Nov., 1890
PROVISIONAL SPECIFICATION.
Improvements in Stuffing-boxes for Steam-engine Cylinders and
other Apparatus.
I, MATTHEW DUNLOP, of Neilston Thread Works, Neilston, in the County of
Renfrew, North Britain, Engineer, do hereby declare the nature of this invention to be
as follows, that is to say :-
My said invention has for its objects to reduce friction in stuffing boxes, to improve
the lubrication of the rods working through them, to diminish the wear of the rods and
packing, and to reduce the costs for lubricants and repairs.
In carrying out my invention according to one modification I employ a stuffing
box of considerable length especially when steam of high pressure is to be used;
and I fill up the box nearly to the top with a brass liner or tube, or with an iron
tube internally lined with brass or other suitable metal, the tube at its inner end
occupying the place of the ordinary neck bush.
The internal surface of the brass or other tube is made an accurate fit to the
piston rod or other rod, but a number of separate small annular grooves are
formed in the internal surface to retain the lubricant and to constitute a succession
of checks to any steam tending to pass them. The grooves are by preference of
a peculiar form adapted to the circumstances of each case. In the case of a
cylinder in which the internal pressure is always greater than the atmosphere the
outer corner of each groove is made with a sharp overlying edge whilst the other
corner is rounded; but in the case of a cylinder in which the prossure is sometimes
less than the atmosphere both corners of the groove are made with sharp overlying
edges. The gland of the stuffing box is by preference made with grooves like those
hereinbefore described; but a ring of any suitable soft or compressible packing is
interposed between it and the inner tube or liner. The grooves or their equivalent
may be formed in any convenient way. Thus each groove may be turned out
separately in a lathe; or a helical groove may be formed and be made discontinuous by
being filled up at numerous points; or the tube or liner may consist of a series of
short tubes or rings with their junction edges shaped to form grooves.
According to a simplified modification which will answer very well for many
applications the stuffing box is provided with a comparatively long tube or liner made
without grooves, but combined with a single narrow ring of soft or compressible
packing placed at the outer end of the box.
Dated this Nineteenth day of December 1889
EDMUND HUNT,
Applicant's Agent.
COMPLETE SPECIFICATION.
Improvements in Stuffing-boxes for Steam-engine Cylinders and
other Apparatus.
I, MATTHEW DUNLOP, of Neilston Thread Works, Neilston, in the County of
Renfrew, North Britain, Engineer, do hereby declare the nature of this invention
and in what manner the same is to be performed, to be particularly described and
ascertained in and by the following statement, that is to say :-
My said invention has for its objects to reduce friction in stuffing boxes, to improve
the lubrication of the rods, working through them, to diminish the wear of the rods and
packing and to reduce the costs for lubricants and repairs.
In carrying out my invention according to one modification, and as shown in vertical
section in Figure, 1, on the accompanying sheet of explanatory drawings, I emplov a

page_text: stuffing box, A, of considerable length especially when steam of high pressure is to be
used; and I fill up the box nearly to the top with a brass liner or tube, or with an
iron tube, B, internally lined with a tube, C, of brass or other suitable metal, the
tube, C, at its inner end occupying the place of the ordinary neck bush.
The internal surface of the brass or other tube, C, is made an accurate fit to the
piston rod or other rod, D, but a number of separate small annular grooves, Ẹ, are
formed in the internal surface to retain the lubricant and to constitute a succession of
checks to any steam tending to pass them. The grooves, D, are by preference of a
peculiar form adapted to the circumstances of each case. In the caso of a cylinder in
which the internal pressure is always greater than the atmosphere the outer corner of
each groove is made with a sharp overlying edge, F, as shown on an enlarged scale in
Figure, 2, whilst the other corner is rounded; but in the case of a cylinder in which
the pressure is sometimes less than the atmosphere both corners of the groove are
made with sharp overlying edges, H, as shown in Figure, 3. The gland, J, of the
stuffing box is by preference made with grooves, B, on its inner surface like those
herein before described; but a ring, K, of any suitable soft or compressible packing is
interposed between it and the inner tube or liner, B, C. The grooves, E, or their
equivalent may be formed in any convenient way. Thus each groove may be turned
out separately in a lathe; or a helical groove may be formed and be made discontinuous
by being filled up at numerous points; or the tube or liner, C, may consist of a
series of short tubes or rings with their junction edges shaped to form grooves.
According to a simplified modification which will answer very well for many
applications the stuffing box is provided with a comparatively long tubo or linor made
without grooves, but.combined with a single narrow ring, K, of soft or compressible
packing placed at the outer end of the box.
Having now particularly described and ascertained the nature of my said inven-
tion and in what manner the same is to be performed, 1 declare that what I
claim is :-
1. Constructing a stuffing box for a steam-engine cylinder or other apparatus with
a long inner lining tube, C, fitting the rod and formed with grooves on its inner
surface, a narrow ring, K, of compressible packing material being interposed between
it and the gland, J, substantially as hereinbefore described.
2. Constructing a stuffing box for a steam-engine cylinder or other apparatus, with
a long inner lining tube fitting the rod and with a narrow ring of compressible packing
material interposed between it and the gland, substantially as herein before described.
Dated this Seventeenth day of September 1890.
EDMOND HUNT
DDMIND FINT
Applicant's Agent.