Improvements in Gas Retort Lids and in the Materials and Method Employed for Ensuring Gas Tight Joints between the Lids and the Mouthpieces.
Year: 1887

page_text: Improvements in Gas Retort Lids and in the Materials and Method
Employed for Ensuring Gas Tight Joints between the Lids and
the Mouthpieces.
We JOHN GREAVES HAWKINS, of Granville Street, Gas Engineer and JOHN BARTON,
Engineer and Secretary of the Gas Works, both of Peterborough, in the County of
Northampton, 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 has for its object the production of gas rotort lids in such a manner
that they may by the application of the materials and method hereinafter stated
ensure gas tight joints between the said lids and the mouthpieces.
In order that the invention may be easily understood drawings are attached hereto,
Fig. being a plan of the mouthpiece with a lid partly in plan and partly in sectional
plan, Fig. 2 a side elevation of one of the brackets attached to the lid, and Fig. 3 a
side elevation of one of the car's attached to the mouthpiece.
The invention consists in making the lid A of wrought iron, cast iron, malleable
iron, or preferably of steel, with a strengthening rib or ribs B. That part of the lid
near the circumference is made of the shape shown, and in it is formed a dovetailed
groove. The lid is supported by the cross bar through the intervention of brackets CC.
The cross bar is hinged on one side at E to the car F of the mouthpiece, and on the
other side rests on the opposite car G of the mouthpiece H. This ear G is made of
the form shown in Fig. 3. The lower part of it is a lead and rest for the cross bar,
while the upper part which is pivotted at M rises when the cross bar is pushed towards
the mouthpiece and falls immediately on the lid being closed, the catch N preventing
the cross bar from moving outwards until intentionally released by lifting the catch.
The brackets C Care either screwed, rivetted, or otherwise fixed at one end to the lid,
the other end being forked so as to receive the cross bar to which they are fastened
by pins L, one of which passes through a slot hole in each bracket. The ears (
and F are fixed to the ear boxes of the mouthpieces by cotters in the usual way or by
set screws as shown on the drawing. The dovetailed groove J is filled with an elastic
composition made of iron borings, fire clay, lime and some fibrous matter such as

page_text: chopped hay, spun yarn, refuse flax, waste cocoa nut fibre or other similar suitable
material, and formed into a plastic compound by the addition of water. A convenient
way of applying the composition is found to be by twisting the fibrous material into
a sort of loose rope and drawing it through or covering it with the paste or plastic
compound. The covered rope is then rammed into the groove and care is taken that
the groove is completely and tightly filled and its surface slightly projects beyond that
of the lid. Another method of serving the groove is by caulking it with the
composition but the former plan is preferred on account of the elasticity of the
composition being better preserved. With the groove so filled with this composition
the lid is swung so as to bring the composition into contact with the edge of the
mouthpiece, when upon pressure being applied by turning the handle I of the screw K,
or by the action of a cam, a true impression of the edge of the mouthpiece will bo
taken by the composition which on being dried will become and remain an exact
counterpart of the said edge. The result will be a perfect fit between the lid and the
mouthpiece whenever the two surfaces are again brought together, so that a sound
gas tight joint may be thus made and maintained.
Having now particularly described and ascertained the nature of our said
invention, and in what manner the same is to be performed, we declare that what we
claim is,
1. The construction of dovetail-grooved gas retort lids having brackets C, C, and
as herein described and shown on the drawings, and
2. The composition herein before described and applied as herein before directed.
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