Improvements in Packing for Hydraulic, Steam, and other Machinery.
Year: 1895

page_text: Date of Application, 26th Aug., 1895
Complete Specification Left, 26th May, 1896-Accepted, 4th July, 1896
PROVISIONAL SPECIFICATION.
Improvements in Packing for Hydraulic, Steam, and other
Machinery.
I, PERCY HULBURD, of the Firm of Hulburd Brothers & Co. of 150, Leadenhall
Street, in the City of London, Engineering Supply Contractors, do hereby declare
the nature of this invention to be as follows :-
:-
This invention relates to improvements in composite metallic packing for
hydraulic, steam and other machinery.
In composite metallic packing as heretofore generally manufactured it has been
found that the soft metal does not, with high pressures, form a tight joint against
the walls of the stuffing-box, unless forced against them with such a pressure as to
prevent its subsequent extraction, and it has also been found that with certain
classes of machinery a fibrous core is liable not only to act as a corrosive but also
to be washed or blown away into delicate parts of the machine.
The object of this invention is to provide a metallic packing which shall be free
from the above named objections.
In inanufacturing my improved composite metallic packing I employ a bush or
ring of soft metal advantageously formed in halves and compressed between
inclined surfaces formed by the usual back-bush and stuffing-gland respectively,
two flat brass rings being sprung or otherwise fixed on to the said soft metal bush
or ring at its points of contact with the gland and back-bush, in such a way that
when the soft metal is compressed by the action of the gland screws it will bear
upon the rod and the brass rings will bear upon the walls of the stuffing box.
In practice I find it advantageous to form each of the brass rings with a flange
on one edge in such a manner that the inner circumference of the flange shall fit
tight in a recess in the soft metal bush, the larger circumference of the ring tightly
embracing the larger periphery of the soft metal bush. In order that the rings
may tightly grip the two halves of the soft bush, they are advantageously split or
sawn through on one side so that they can be sprung on to the two halves of the
bush.
The ends of the bush are coned off to an angle, the brass rings being also turned
to an angle to form a continuation of this cone; the cone of the brass ring should
be made as large as possible having regard to the fact that the inner diameter
must be large enough to slide over the enlarged end of the piston-rod. The object:
of this is, to give as large a bearing surface as possible of the brass ring against the
cones of the back-bush and gland, as well as to give sufficient strength at the larger
periphery of the bush to prevent the pressure of the gland and back-bush
acting unequally on the brass ring and tearing the soft metal and causing a
leakage.
1
1005

page_text: Improvements in Packing for Hydraulic, Steam, and other
Machinery.
I, PERCY HULBURD, of the Firm of Hulburd Brothers & Co., of 150, Leaden-
hall Street, in the City of London, Engineering Supply Contractors, 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:-
This invention relates to improvements in composite metallic or metallic packing
for hydraulic, steam and other machinery.
In composite metallic packing as heretofore generally manufactured it has been
found that the soft metal does not, with high pressures, form a tight joint against
the walls of the stuffing-box, unless forced against them with such a pressure as
to prevent its subsequent easy extraction, and it has also been found that with
certain classes of machinery a fibrous core is liable not only to act as a corrosive
but also to be washed or blown away into delicate parts of the machine.
The object of this invention is to provide a metallic packing which shall be free
from the above named objections.
In manufacturing my improved composite metallic packing I employ a bush or
ring of soft metal advantageously formed in balves and compressed be reen
inclined surfaces formed by the usual back-bush and stuffing gland respectively,
two flat brass rings being sprung or otherwise fixed on to the said soft meta! bush
or ring at its points of contact with the gland and back-bush, in such a way that
when the soft metal is compressed by the action of the gland-screws it will bear
upon the rod and the brass rings will bear upon the walls of the stuffing-box,
forming a lining between them and the soft metal bush.
In practice I find it advantageous to form each of the brass rings with a flange on
one edge in such a manner that the inner circumference of the flange shall fit tight
in a recess in the soft metal bush, the larger circumference of the ring tightly
embracing the larger periphery of the soft metal bush. In order that the rings
may tightly grip the two halves of the soft bush, they may be advantageously
split or sawn through on one side so that they can be sprung on to the halves of
the bush.
The ends of the bush are coned off to an angle, the brass rings being also turned
to an angle to form a continuation of this cone; the cone of the brass ring should
be made as large as possible having regard to the fact that the inner diameter must
be large enough to slide over the enlarged end of the piston-rod. The object of
this is to give as large a bearing surface as possible of the brass ring against the
cones of the back-bush and gland, as well as to give sufficient strength at the
larger periphery of the bush to prevent the pressure of the gland and back-bush
acting unequally on the brass ring and tearing the soft metal and causing a leakage.
To enable my invention to be fully understood I will describe the same by
reference to the accompanying drawing, in which :-
Figure 1 is a end view of my improved packing:
Figure 2 is a longitudinal section of the same:
Figure 3 is a section similar to Figure 2 but shewing the metal rings removed;
and,
Figure 4 is a section of one of such rings detached:
Figure 5 is a longitudinal section shewing the application of my improved
packing to a stuffing-box.
a is the metal packing, and b, b are the metal rings which I place around the
said packing at the points which come into contact with the walls of the stuffing-
box, the said rings being advantageously split as at a¹ and provided with flauges c

page_text: which enter corresponding rebates or recesses in the packing. The outer faces d
of such flanges are shaped as shewn to correspond with the inclination of the ends
of the packing, so that they will fit against the cone ends of the backbush and
gland.
Having now particularly described and ascertained the nature of my said inven-
tion and in what manner the same is to be performed, I declare that what I
claim is :-
1. The combination with metallic or composite metallic packing of metal rings,
substantially as, and for the purpose, described.
2. The manufacture and use of metallic or composite metallic packing having
metal rings applied thereto, substantially in the manner hereinbefore described
and illustrated in the accompanying drawing, for the purpose specified.
Dated the 26th day of May 1896.
G. F. REDFERN & Co.,
4, South Street, Finsbury, London, Agents for the Applicant.