Improvements in or Applicable to Stuffing Boxes for Steam and other Machinery.
Year: 1888

page_text: Date of Application, 3rd Nov, 1888
Complete Specification Left, 3rd. Aug., 1889-Accepted. 14th Sept.. 1889
PROVISIONAL SPECIFICATION:
Improvements in or Applicable to Stuffing Boxes for Steam and
other Machinery.
I NORMAN MACBETH of the Victoria Foundry, Bolion in the County of Lancaster,
Engineer, do hereby declare the nature of this Invention to be as follows:-
My Invention relates principally to the packing, or stuffing boxes of prime
movers as for example to stuffing boxes for the piston and valve rods of steam
engines but I do not confine myself to the application to this particular class of
machinery. Previously to my invention such stuffing boxes have been provided
with metallic packing which has been free to some extent to accomodate itself
bodily to deviations of the piston rod or valve rod from its true or original central
position in the stuffing box due to the wear or settling down of the piston or valve
or to other canses. In my invention I enclose the packing within a packing box
which is held within or partly within the ordinary stuffing box or a chamber
corresponding thereto and is free to move within limits in all directions excepting
in the direction of the longitudinal movement of the piston rod or valve rod. By
preference I arrange for the tightening or adjustment of the packing and all the
parts to be effected by means of one set of bolts or screws. In one arrangement
the said packing box is in the form of a hollow cylinder having a flange which
is truly faced and scraped or prepared to have a true plane surface which bears
upon a corresponding surface upon a ring or flange which is secured to the
cylinder head or cover or to the end of the valve chest. The packing material is
enclosed between two glands which enter the two ends of the packing box. The
inner one of these two glands is formed with a prepared plane surface which
bears upon a corresponding surface formed upon a ring which is tightly fixed in the
bottom of the chamber in the cylinder cover. The outer one of the said glands is
connected by means of bolts with the flange of the packing box. Spiral or other
suitable springs may be introduced between the nuts and the said outer gland.
The effect of the arrangement is that the packing or packing material is com-
pressed or held in contact and the aforesaid prepared plane surfaces are also kept in
contact by the tension or pressure exerted by the said bolts whilst the plane
surfaces upon the packing box and inner gland are free to slide to some extent
upon the fixed plane surfaces. The packing box may contain any suitable metallic
packing or he packed with any ordinary or suitable engine packing or stuffing
box packing material. In some cases form the packing box and the inner gland
with spherically formed surfaces which fit in or upon corresponding surfaces upon
rings which are prepared to slide upon the aforesaid fixed plane surfaces or the
prepared surfaces on the packing box and the inner gland may be plane and may
slide upon loose rings which are plane on one side and spherical on the side in
contact with the flanges or parts of the casing enclosing the packing box.
I may
make other modifications in the arrangements as for example the plane or spherical
sliding surfaces might be in or on a part or in parts secured outside the opening
in the cylinder head or cover or the ordinary neck through which the rod passes
and the packing box might be formed in two parts fitting together telescopically
and in some cases the packing box and its connected parts might constitute a
complete connected appliance which could be bolted or secured to the flange of the
ordinary stuffing box or to the said neck or to the cylinder cover or other part through
which the piston rod or valve rod would pass. In all cases the principal
feature of my invention is that the adjustment of the internal wearing surfaces and

page_text: the tightening of the packing material is accomplished by the action of nuts and
bolts or screws, with or without springs, placed in easily accessible positions outside
the casing containing the packing box and packing material.
Th
1000
DUTTON & FULTON,
1. St. James Square. Manchester, Agents.
COMPLETE SPECIFICATION.
Improvements in or Applicable to Stuffing Boxes for Steam and
other Machinery.
I NORMAN MACBETH of the Victoria Foundry, Bolton, in the County of Lancaster,
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 and accompanying drawings
My Invention relates principally to the packing or stuffing boxes of prime movers
as for example to stuffing boxes for the piston and valve rods of steam engines
but I do not confine myself to the application to this particular class of machinery.
Previously to my invention such stuffing boxes have been provided with metallic
packing which has been free to some extent to accomodate itself bodily to deviations
of the piston rod or valve rod from its true or original central position in the
stuffing box due to the wear or settling down of the piston or valve or to other
causes. In my invention I enclose the packing within a packing box which is free
to move within limits so as to accomodate itself to the slight variation of the piston
rod from its line or original line of movement and I arrange for the tightening
or adjustment of the packing and all the parts to be effected by means of one set
of bolts or screws.
In order that my Invention may be well understood I will describe the same
with reference to the accompanying drawings which for convenience of description
I will suppose illustrate the application of my Invention to the stuffing box of a
steam engine piston rod. In the said drawings Fig. 1 is a sectional view of a
stuffing box and Fig. 2 is a similar view of a modified form of and method of
mounting such stuffing box. In the said Figs. a is the piston rod of the engine
and is the neck or part in which is formed the chamber which is usually termed
the stuffing box and which in ordinary cases receives the packing. In my improved
construction the packing is contained in a stuffing box c which in the example
illustrated by Fig. 1 is seated partly within the chamber in the neck b. The
stuffing box c consists of two parts c. c¹ the part c entering into the part c¹ and
being fitted to slide therein. The lower or inner end of the part c is formed with
a collar which is turned to have a spherically shaped face which fits in a concave
seating which is turned in a loose ring d which is supported by a fixed seating e.
The upper or outer end of the part c is also formed with a collar upon which is
formed a spherically shaped face which fits in a concave seating which is formed
on a loose ring which is supported by a cover ring g. The surfaces of the parts d
and e and of the parts ƒ and g which are in contact are truly faced and scraped
or prepared to have as nearly as may be true plane surfaces which are at right
angles to the line of motion of the piston rod and are therefore intended to be
parallel with each other and the rings and are free to slide upon the parts e
and 9.
The surfaces of the parts c and d and of the parts c¹ and which are in
contact are turned and ground or finished to be in each case parts of a true sphere
which should have its centre coinciding with the centre line of the piston rod these
spherically curved joints permitting of slight rocking or inclined movements of
the stuffing box. All the said surfaces should be finished with care so as by their
contact with one another to furnish joints which shall be suitably steam tight. The
ring g is secured to the flange upon the neck b by means of bolts h. h. The
stuffing box is filled with packing which in the example selected for illustration

page_text: consists of split rings of anti-friction metal but any suitable packing or packing material
may be used. The said packing is compressed by means of bolts i acting upon a
gland as is usual. It will be seen that as the packing is compressed between the
said gland and the inner end of the part c the action of the pressure on the
packing tends to elongate the stuffing box by the outward sliding of the one part
within the other. This has the effect of keeping all of the surfaces of the parts c. d
and e and of the parts and g in contact so that so long as the packing is
compressed in the direction of the line of motion of the piston rod the parts will
be kept in steam tight contact. When the pressure upon the packing is insufficient
for the purpose it is only necessary to tighten the packing in the ordinary manner
by screwing up the nuts at i to the required extent the one adjustment serving
to tighten the packing upon the piston rod and at the same time to tighten the
joints between the said parts. In some cases 1 apply springs between the nuts i
and the gland. By reason of the hereinbefore mentioned freedom of motion of ono
part upon another the stuffing box is free to accomodate itself to slight variations
of the piston rod from its true or original straight line of movement as aforesaid as
for example the stuffing box can accomodate itself to the deviation of the piston rod
from its original line of movement caused by the dropping or wearing of the piston
in the case of a horizontal engine. The example illustrated by Fig. 2 differs from
Fig. 1 principally in that the spherical surface on the part e is formed on a collar
which is upon the inner end of the said part instead of upon its outer end, and that
the ring dis seated upon a larger ring e' which is secured to the neck 6 by means of
screw bolts which may also serve to secure the ring g' to the ring el. The principal
result of this construction is that the stuffing box is not enclosed within the chamber
in the neck bas in the case of Fig. 1 but projects froin the front end of the neck.
This may be a convenient construction either in a case wherein my invention may be
applied to an existing engine or in the case of a new engine. In the latter case it is
evident that the neck b might be dispensed with and the ring e¹ be secured directly to
the body of the cylinder cover as indicated by the dotted lines at l. Figs. 3 and 4
illustrate other modifications in the formation of the parts which constitute the joints
between the stuffing box and the cylinder cover or attached parts. In the example
illustrated by Fig. 3 a collar c upon the part c is formed with a plane surface which
is in contact with a prepared plane surface upon a ring d and a collar cupon the
part el is similarly prepared to fit against a ring f. These rings correspond with the
rings d and f. These rings and fare each formed with a plane surface on one
side and a convex spherical surface on the other side the spherical surface being
prepared to suit a concave seating formed in the fixed part e' or ' as the case may be
so that the practical result is the same as in the cases of the examples illustrated by
Figs. 1 and 2. In Fig. 4 the construction is simplified by dispensing with the rings d
and and with the use of spherically formed surfaces. In this example the plane
surfaces upon the collars c2 and care seated directly upon plane surfaces upon the
parts e and . Although such a construction would enable the stuffing box to
accomodate itself to some extent to the variations in the movements of the piston rod
it is evident that the freedom of the stuffing box would not be so great as in the cases
of the other examples. Although Figs. 3 and 4 are more particularly modifications
of Fig. 2 it will be readily seen how Fig. 1 may be similarly modified. In all of the
examples the parts c. c' d. dff are not prevented from rotating and in practice the
stuffing box is or may be subject to a rotatory inotion either regular or intermittent and
either derived from the motion of the parts in which case it is in a sense accidental, or
caused by manually operating handles or parts projecting from the box. Such a
rotatory motion is an advantage for the reason that irregular wearing of the parts is
prevented and the joints are therefore kept in better working condition.
In all cases
the principal or important feature of my invention is that the adjustment of the
internal wearing surfaces and the tightening of the packing material is accomplished
by the action of nuts and bolts or screws with or without springs, placed in easily
accessible positions outside the casing containing the packing box and packing
material.

page_text: Having now particularly described and ascertained the nature of my said
invention and in what manner the same is to be performed I declare that what
I claim is
(1) The stuffing box with its seating rings formed and applied substantially as set
forth and indicated hereinbefore and in the accompanying drawings.
(2) The stuffing box formed in two parts one sliding within the other, each part
being seated in or upon a ring which is free to inove upon a plane surface one external
set of bolts serving to tighten the packing and the joints between the said rings and
stuffing box and the fixed parts substantially as and for the purpose set forth and
indicated.
(3) The stuffing box formed in two parts one sliding within the other each having a
plane surface which fits a plane surface upon a fixed part the tightening of the
stuffing by the external bolts tending to elongate the box and thereby to keep the
plane surfaces in contact substantially as and for the purpose set forth and indicated.
(4) The stuffing box formed in two parts c. c one sliding within the other
spherically seated in rings d. f the ring or seating e or el the ring g or g' and the
gland constructed and acting substantially as set forth and indicated.
(5) The stuffing box composed of two parts c. c' one sliding within the other with
its gland the plane surfaces on the parts c² 3 and the rings df2 fitted in spherical
seatings substantially as set forth and indicated.
(6) The stuffing box composed of two sliding parts c. c with its gland & the plane
surfaces on the parts cc fitting prepared plane surfaces on the fixed rings or
parts e. g or el g₁ substantially as set forth and indicated.
Dated this 2nd day of August 1900
DUTTON & FULTON,
1, St. James Square, Manchester, Agents.