An Improvement in the Stuffing-boxes for Piston-rods and Valve- rods of Steam Engines.
Year: 1889

page_text: Date of Application, 30th Mar., 1889
Complete Specification Left, 29th Nov., 1889-Accepted, 28th Dec., 1889
PROVISIONAL SPECIFICATION.
An Improvement in the Stuffing-boxes for Piston-rods and Valve-
rods of Steam Engines.
We, ROBERT MARSHALL and EDWARD FITZGERALD, both of No. 121 Fenchurch
Street, in the City of London, Engineers, do hereby declare the nature of this inven-
tion to be as follows:-
-
Our invention relates to the stuffing boxes for the piston rods and slide or valve
rods of high-pressure steam engines in which metallic packing is used. The high-
pressure steam in penetrating into such stuffing boxes behind the metallic packing,
presses the latter with such force against the piston rod or slide rod as to cause the
packing to wear away very rapidly, such pressure being far greater than is required
for maintaining a steam tight contact between the packing and rod.
According to our invention we prevent such wear by connecting tho stuffing box
by means of a pipe or channel with some part of the engine in which the steam is at
a lower pressure than that in the high pressure cylinder, such for instance as the
valve casing of a cylinder working at a lower pressure, or with such cylinder itself, in
the case of compound or multiple expansion engines, or we arrange the pipe to
communicate with the condenser. By the above described means not only is the
metallic packing relieved of the excessive pressure, inasmuch as the pressure in the
stuffing box will be reduced to that existing in the low pressure valve casing or
cylinder, but also, the steam or water of condensation passing from the stuffing box is
saved, which is of importance in marine and other engines working with a limited
water supply.
A non-return or relief valve or cock may be provided on the said communicating
pipe, so arranged that the communication stopped thereby at such times when
the pressure in the stuffing box does not exceed that in the vessel with which it
communicates.
TLLL 00h L...
1. 1990
ABEL & IMRAY,
Agents for the Applicants.
COMPLETE SPECIFICATION.
An Improvement in the Stuffing-boxes for Piston-rods and Valve-
rods of Steam Engines.
We, ROBERT MARSHALL and EDWARD FITZGERALD both of No. 121, Fenchurch
Street. in the City of London, Engineers 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 :-
Our invention relates to the stuffing boxes for the piston rods and slide or
valve rods of high pressure steam engines in which metallic packing is used.
The high pressure steam in penetrating into such stuffing boxes behind the metallic
packing, presses the latter with such force against the piston rod or slide rod as to
cause the packing to wear away very rapidly, such pressure being far greater than
is required for maintaining a steam tight contact between the packing and rod.
According to our invention we prevent such wear by connecting the stuffing box
by means of a pipe or channel with some part of the engine in which the steam is at
a lower pressure than that in the high pressure cylinder, such for instance as the
valve casing of a cylinder working at a lower pressure, or with such cylinder itself,
in the case of compound or multiple expansion engines, or we arrange the pipe to
communicate with the condenser.

page_text: By the above described means not only is the metallic packing relieved of the
excessive pressure, inasmuch as the pressure in the stuffing box will be reduced to
that existing in the low pressure valve casing or cylinder, but also, the steam or water
of condensation passing from the stuffing box is saved, which is of importance in
marine and other engines working with a limited water supply.
A non-return or relief valve or cock may be provided on the said communicating
pipe, so arranged that the communication is stopped thereby at such times when the
pressure in the stuffing box does not exceed that in the vessel with which it com-
municates. The above described arrangement is obviously not intended to apply to
those constructions of metallic packings so designed that the high pressure steam
shall press the rings against the piston or valve rod with which it communicates.
Having now particularly described and ascertained the nature of this inven-
tion and in what manner the same is to be performed we declare. that what we
claim is :-
Connecting the stuffing boxes of a high pressure steam cylinder or slide or valve
chest by a pipe or channel with the slide casing of a cylinder working at a lower
pressure, or with the low pressure cylinder itself or with a condenser, substantially
as and for the purpose described.
Dated this 29th day of November 1889.
ABEL & IMRAY,
Agents for the Applicants.