Improvements in Seats for Steam Pressure Valves.
Year: 1894

page_text: Date of Application, 27th Apr., 1894-
Complete Specification Left. 28th Jan.. 1895-Accepted. 2nd Mar. 1895
PROVISIONAL SPECIFICATION.
Improvements in Seats for Steam Pressure Valves.
I, ALEXANDER TURNBULL, of the Firm of A. Turnbull & Co., Engineers,
Bishopbriggs, in the County of Lanark, do hereby declare the nature of this
invention to be as follows:-
This invention is a development of that described in the Specification of Letters
Patent granted to me No. 6298 of 1893, and it has for its objects to provide a
supplementary seating for valve seats secured in steam chests or casings in the
manner described in said Specification or by studs and nuts or like means, and also
to provide a valve seat in steam chests or casings which shall be kept steam tight
by its own expansion and contraction.
As a supplementary seating for valve seats I fit in a groove formed in the metal
of the steam chest or casing directly under the lower edge or annular base of the
removable or fixed valve seat a ring of gun metal, brass or like material upon the
upper face of which the lower edge of the valve seat bears to form a steam tight
joint and prevent the passage of steam around the seat should it become loose by
repeated expansion and contraction. Or in lieu of the valve seat and supplementary
seating I fit within the steam chest or casing a valve seat having on its upper side
a bearing face for the valve and a ring or flange on its lower side fitting into a
groove formed in the metal of the steam chest or casing, said ring bearing tightly
against one side or other of the groove according as it expands or contracts under
variations of temperature.
Dated this 26th day of April 1894.
CRUIKSHANK & FAIRWEATHER,
62, St. Vincent Street, Glasgow, Agents.
I, ALEXANDER TURNBULL, of the Firm of A. Turnbull & Co., Engineers,
Bishopbriggs, in the County of Lanark, 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 is a development of that described in the Specification of Letters
Patent granted to me No. 6298 of 1893, and it has for its objects to provide a
supplementary seating for valve seats secured in steam chests or casings in the
manner described in said Specification or by studs and nuts or like means, and also.
to provide a valve seat in steam chests or casings which shall be kept steam tight
by its own expansion and contraction due to variations of temperature.
The invention is illustrated in vertical section of a steam pressure valve at
Figure and under a modification in part vertical section of a valve seat at
Figure 2.
As a supplementary seating for valve seats 1 fit in a groove a formed in the
metal of the steam chest or casing A directly under the lower edge or annular base

page_text: of the removable or fixed valve seat B a ring C of gun metal, brass or like material
upon the upper face of which the lower edge of the valve seat B bears to form a
steam tight joint and prevent the passage of steam around the seat B should it
become loose by repeated expansion and contraction. Or in lieu of the valve seat
and supplementary seating I fit within the steam chest or casing a valve seat D as
shown at Figure 2 having on its upper side a bearing face d for the valve and a
ring or flange d' on its lower side closely fitting into a groove a formed in the
metal of the steam chest or casing A, said ring bearing tightly against one side
or other of the groove a according as it expands or contracts under variations of
temperature.
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. A steam pressure valve provided with a loosely fitting seat and a supplementary
rigidly fixed seating substantially as described with reference to Figure 1 of the
annexed drawings.
2. In a steam pressure valve a seat having on its upper side a bearing face for
the valve and on its lower side a ring or flange tightly fitting in a groove in the
steam chest or casing substantially as described with reference to Figure 2 of the
annexed drawings.
Dated this 26th day of January 1895.
WALLACE FAIRWEATHER;
Chartered Patent Agent,
62, St. Vincent Street, Glasgow, Agent for the Applicant.