Improvements in Stuffing Box Packing.
Year: 1895

page_text: This Print is in accordance with the Original Specification as it stands after
Amendment (under Section 11 of the Patents, &c., Act, 1883), as required by
the decision of the Law Officer of the 3rd day of December 1896.
Improvements in Stuffing Box Packing.
I, CHARLES CHRISTOPHER BRAITHWAITE, of Kirkwick, Harpenden, in the
County of Herts, Engineer, do hereby declare the nature of this invention to be
as follows:-
My invention has reference to a construction of packing readily removable & to
fit existing stuffing boxes adapted to be acted upon by fluid pressure and designed
to effectually prevent leakage of fluid such as steam where a moving part such as
a piston rod passes through the wall of a vessel such as a cylinder. Around the
rod within the stuffing box I provide a soft metal bush made in two or more parts
portions of which are made sufficiently thin to be caused by the pressure of fluid
which I admit behind them to press against the rod thus maintaining between the
soft metal and the rod practically a fluid tight joint. In one form the soft metal
bush is in two parts each adapted to extend half round the rod and made with the
longitudinal edges thickened and faced; and when the two parts are together the
bush has externally the general form of two truncated cones base to base, one part
cone constituting the outer end of the bush having its sides inclined to a less acute
angle than the other-which latter has external recesses to admit fluid to press
the inner surface of the bush against the rod. This formation may be varied.
Surrounding the more acutely coned part of the soft metal bush is another or
intermediate bush of suitable material such as gun metal; it is made at its smaller
or inner end with an inwardly projecting lip that overlaps (or partly so) the inner
end of the soft metal bush, and also is formed with passages adapted to conduct
fluid from the interior of the vessel or cylinder to which my invention is applied to
recesses of the soft metal bush for the purpose already mentioned. The lining of
the stuffing box surrounds the intermediate bush and is made at its inner end with
an inwardly projecting lip or shoulder that partly overlaps the inner end of the
intermediate bush; and at its outer end with a flange. With this arrangement, by
removing the bolts that secure the various parts together and to the stuffing box
and then withdrawing the lining, the intermediate bush and the inner or soft metal
bush will simultaneously be withdrawn.
If the rod be made with an enlargement or swelling, 1 make the hole through the
gland large enough to clear such enlargement and provide a lining of suitable material
such as gun metal made in parts screwed to the gland and adapted at their inner
ends to partly overlap the inner end of the gland, and also to fit the outer end of
the soft metal bush so that on tightening the screws that secure the various parts

page_text: together there will be a tendency to press the inner surface of the soft metal bush
against the rod.
Dated this 30th day of March 1895.
I, CHARLES CHRISTOPHER BRAITHWAITE, of Kirkwick, Harpenden, in the
County of Herts, 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 :-
My invention has reference to a construction of packing readily removable and to
fit existing stuffing boxes, adapted to be acted upon by fluid pressure and designed
to effectually prevent leakage of fluid such as steam where a moving part such as a
piston rod passes through the wall of a vessel such as a cylinder. Around the rod
within the stuffing box I provide a soft metal bush made in two or more parts
portions of which are made sufficiently thin to be caused by the pressure of fluid
which I admit behind them to press against the rod thus maintaining between the
soft metal and the rod practically a fluid tight joint.
Fig. 1 of the accompanying illustrative drawings shows one form of my improved
stuffing box packing in central longitudinal section.
Fig. 2 shows a cross section of the soft metal bush in line X-X of Fig. 1, and
Fig 3 shows in elevation the smaller end of the intermediate bush.
The soft metal bush is in two parts A A' each adapte to extend half round the
rod B and made with their longitudinal edges a a' thickened and faced; and as
will be seen when the two parts are together as shewn the bush has externally the
general form of two truncated cones base to base, one part cone, constituting the
outer end of the bush, having its sides inclined to a less acute angle than the other
-which latter has external recesses 6 6¹ to admit fluid to press the inner surface of
the bush against the rod B. This formation may be varied. Surrounding the
more acutely coned part of the soft metal bush A A' is another or intermediate
bush C of suitable material such as gun metal; it is made at its smaller or inner
end with an inwardly projecting lip that overlaps (or partly so) the inner end of
the soft metal bush A A and is formed with passages c² adapted to conduct fluid
from the interior of the vessel or cylinder to which iny invention is applied to the
recesses of the soft metal bush A A' for the purpose already mentioned the
fluid passing through the passages a² of the soft metal bush into its recesses bb'.
The lining D of the stuffing box surrounds the intermediate bush C and is made at
its inner end with an inwardly projecting lip or shoulder & that partly overlaps the
inner end of the intermediate bush; and at its outer end with a flange d¹. With
this arrangement, by removing the nuts E and then withdrawing the lining D
(which can be done by unscrewing nuts e) the intermediate bush Čand the inner
or soft metal bush A A' will simultaneously be withdrawn.
If the rod B be made with an enlargement or swelling (as at 63) I make the
hole through the gland F large enough (as shewn) to clear such enlargement 63 and
provide a lining G of suitable material such as gun metal made in parts screwed to
the gland and adapted at their inner ends to partly overlap the inner end of the
gland, and also to fit the outer end of the soft metal bush A. A' so that on tightening
the nuts E there will be a tendency to press the inner surface of the soft metal
bush A A¹ against the rod.

page_text: Having now particularly described and ascertained the nature of the said
invention and in what manner the same is to be performed I know it has been
proposed to form a metallic packing ring adapted to be compressed between two
oppositely inclined surfaces with a hollow or a concave recess in that side of the
ring opposite to the working face, and to this feature, considered separately, I lay
no claim, but I declare that what I claim is: :-
1. In a stuffing box packing a soft metal bush divided longitudinally into two or
more parts with recessed outer faces these parts being arranged within the stuffing
box around and so as practically throughout the length of the bush to bear with
their inner faces against the rod to be packed with provision for admitting to the
recesses fluid pressure in such a manner that portions of the bush made sufficiently
thin are caused to press against the rod, thereby maintaining between the bush and
the rod a practically fluid tight joint as set forth.
2. A stuffing box packing comprising a soft metal bush made in parts with
recesses in their outer surfaces and with longitudinal edges thickened and faced, an
intermediate bush surrounding the soft metal bush, and enclosed within the stuffing
box lining and provision for admitting fluid such as steam to the spaces formed by
the recesses in the soft metal bush between its thinner portions and the intermediate
bush so that the soft metal bush may be pressed into close contact at its inner
surface with the surface of the rod for the purpose of thereby making a practically
fluid tight joint substantially in the manner described.
3. The lining D adapted to fit accurately within the stuffing box and made with
an inwardly projecting lip or shoulder and an outwardly projecting flange such that
the lining and the parts enclosed between it and the rod B can be withdrawn by
unscrewing the nuts e as described.
4. My improved stuffing box packing as described and illustrated.
Dated this 17th day of December 1895.
For the Applicant,
W. LLOYD WISE,
46 Lincoln's Inn Fields, London, W.C., Chartered Patent Agent.