Improvements in or relating to Quadruple Expansion Steam Engines, and in Valves Applicable to Triple or Quadruple Expansion or other Engines.
Year: 1888

page_text: Date of Application, 4th Sept., 1888
Complete Specification Left, 4th June, 1889-Accepted, 13th July, 1889
PROVISIONAL SPECIFICATION.
Improvements in or relating to Quadruple Expansion Steam Engines,
and in Valves Applicable to Triple or Quadruple Expansion or
other Engines.
I, THOMAS MUDD, of the Central Engine Works, West Hartlepool, in the County
of Durham, Engineer, do hereby declare the nature of this invention to be as
follows:-
The invention relates to quadruple expansion steam engines.
I place the first cylinder in the centre at the top, the second cylinder immediately
beneath the first, and the third and fourth at the respective sides of the second.
The first cylinder may either be close down to, and form the cover for, the second
cylinder, or may be raised to allow of a pair of ordinary glands.
The arrangements for economising steam in the second, third, and fourth cylinders
are the same as in my well-known triple expansion engines, namely, there is a steam
jacket round the second cylinder, which jacket radiates heat into steam of lower
temperature both from its inner and outer surfaces; that is, the inner surface radiates
into the second cylinder, preventing loss of heat therefrom, and the outer surface
radiates into the low pressure steam chest or-receiver which is carried round the
jacket for that purpose, thus preventing condensation therein. The third cylinder is
arranged to exhaust by two pipes or passages (one each side) so as to throw the
steam exhausting therefrom against the two sides of the jacket, and cause it to traverse
round same on its way to the low pressure valve.
A simple arrangement by which the valve ends or bearing parts are practically solid,
and are yet capable of being adjusted to a larger diameter so as to follow up any
wear that takes place, is as follows:-
I make the bearing parts or ends of the valve loose from the valve body, and at one
point in the periphery of these ends, I make a pair of internal flanges which can be
bolted together by bolts or otherwise secured one to the other. When the flanges are
bolted solidly together, the valve end is turned in the lathe to the size required, and
is set to work in the engine, thus securely bolted, so that when at work, it is in
reality solid and inexpansible, being quite without springs or packing rings of any
kind. For this reason the steam has no power to cause the valve to press upon the
surfaces of the chamber in which it works, the power required to drive it being thus
a minimum, and very much less than when rings and springs are used.
When the valve has become slack in its chamber through wear, the flanges can be
released from each other and a thin liner inserted. between them the full width of the
flange, and the bolts put in again. By this means the valve ends or bearing parts
can be enlarged at will to a great degree of nicety in diameter, and still retain their
character of solidity in inexpansibility whilst working in the engine.
They may be single ported, double ported, and so forth at will.
The valve of the first cylinder may be either a common slide valve or a piston
valve. When the latter, I may make it as described in my Patent No. 12825 of 1886
or as described herein.

page_text: COMPLETE SPECIFICATION.
Improvements in or relating to Quadruple Expansion Steam Engines,
and in Valves Applicable to Triple or Quadruple Expansion or
other Engines.
I, THOMAS MUDD, of the Central Engine Works, West Hartlepool, in the County
of Durham, Engineer, do hereby declare the nature of this invention and in what
nanner the same is to be performed, to be particularly described and ascertained
in and by the following statement:-
This invention relates to quadruple expansion steam engines, and to valves applicable
for triple or quadruple expansion or other engines,
The object of the first portion of the invention is to so arrange the engine (more
especially the cylinders) that a great economy in steam is secured, and this arrange-
ment of the cylinders offers special advantages in transforming triple expansion into
quadruple expansion engines without much disturbance of existing parts.
Referring to the drawings
Figure 1 is a side elevation of those portions of a quadruple expansion engine which
are sufficient to explain this part of my invention.
Figure 2 is a horizontal section of Figure 1.
Figure 3 is a vertical section through one of my improved piston valves.
Figure 4 is a plan of same.
Referring first more especially to Figures 1 and 2 :-
1 place the first cylinder A in the centre at the top, the second cylinder B
immediately beneath the first, and the third C and fourth D one on each side of
the second.
The first cylinder A may either be close down to, and form the cover for, the
second cylinder B, as shown in the drawings, or it may be raised to allow of a pair
of ordinary glands being placed around the piston rod. It will be understood that
the piston rod passes between the cylinders A and B, and is connected to the pistons
in each in such a manner as to reciprocate with them.
The arrangements for economising steam in the second, third, and fourth cylinders
are the same as in my well known triple expansion engines, namely, there is a steam
jacket B round the second cylinder B, which is supplied with steam, preferably
from the boiler direct. This jacket radiates heat into steam of lower temperature
both from its inner and outer surfaces; that is, the inner surface radiates into the
said second cylinder B, preventing loss of heat therefrom, and the outer surface
radiates into the low pressure steam chest or receiver B³, which is carried round the
jacket for that purpose, thus preventing condensation therein. The third cylinder C
is arranged to exhaust by two pipes or passages C (one each side) so as to throw the
steam exhausting therefrom against the two sides of the jacket, and cause it to
traverse round same on its way to the low pressure valve as hereinafter described.
The exhaust high pressure steam passes from the valve chamber a by a pipe a', into
the steam chest 6 of the second cylinder B, and thence into the said cylinder B. The
exhaust ports of this cylinder B open into steam passages 61, and from these the
steam passes through the valve chamber c into the third cylinder C. The exhaust
steam from the cylinder C on its way to the low pressure cylinder passes by two
pipes into a chamber B2 which, as aforesaid, surrounds the steam jacket B¹ of the
second cylinder -B. After being further heated by means of the radiation from the
outer wall B of the steam jacket, the low pressure steam passes through the valve
chamber d into the low pressure cylinder D, and thence to the exhaust. In the
drawing, the arrows will serve to illustrate the course of the steam.
With an arrangement of cylinders such as described above, a triple expansion can
easily be converted into a quadruple expansion engine, or vice versa.
The valve of the first cylinder may be either a common slide valve or a piston
valve. When the latter, I may make it as described in my Patent No. 12359 of 1885,
or as described hereunder.

page_text: 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. In a quadruple expansion engine the arrangement of the high pressure cylinder
above the second cylinder with the third and fourth cylinders at each side of the
second cylinder, the bottom of the high pressure cylinder either forming the top
of the said second cylinder or being separated from the same, substantially as
described.
2. In a quadruple expansion engine having its first cylinder set upon the top of the
second cylinder, the arrangement, substantially as described and shown, for passing
the steam from the said first cylinder to the said second cylinder.
Dated this 3rd day of June 1889.
WM. P. THOMPSON & Co.,
Of 6, Lord Street, Liverpool, Patent Agents for the Applicant.