Improvements in Apparatus for Regulating the Seal in and for Drawing off Tar and Liquor from Hydraulic Mains of Gas Works and similar Receivers.
Year: 1891

page_text: Date of Application, 31st Dec., 1891-Accepted, 6th Feb., 1892
COMPLETE SPECIFICATION.
Improvements in Apparatus for Regulating the Seal in and for
Drawing off Tar and Liquor from Hydraulic Mains of Gas Works
and similar Receivers.
I, GEORGE ROBERTSON HISLOP, of the Gas Works, Paisley, in the County
of Renfrew, Engineer and Gas Works Manager, 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 by improved apparatus to afford greater facility
for regulating the seal in and for drawing or conducting away the tar from
hydraulic mains in gas works and from like receivers and also to afford means for
shutting off communication of the main with the discharge pipe without the use of
stop cocks and as shewn in vertical section at Figure 1 in plan at Figure 2 and in
elevation looking from X Figure at Figure 3 of the accompanying drawings the
improved apparatus consists of a vessel A preferably cylindrical in form but which
may be of other shape and which is suspended at one side of the hydraulic main B
by hooks or catches C taking over angle iron bars D bolted to the top of the main
or by other means of suspension.
The vessel A is at its upper end connected by a pipe E to the top of the
hydraulic main for the purpose of equalising the pressure in both and it is also
connected by a pipe or branch E' to the bottom of the main whilst to the lower
part of the vessel a flanged tee shaped pipe F is secured the vertical branch F' of
the pipe passing up through the centre of the vessel to such a height that its upper
end is level or about level with the bottom of the main B as shewn so as to be
capable of emptying or drawing off the whole of the tar and liquid therefrom.
Over the upper end of the branch F' and which is turned true externally a
hollow piston G is fitted the piston being bored out to receive the branch and
render the same tar and water tight.
The upper end of the hollow piston G is closed by a faced flange plate G¹ bolted
to a faced flange on the piston and in the centre of the plate a spindle or lifting
rod H is secured the said rod which is screwed at its upper end passing through a
stuffing box in the cover of the vessel A and thence through a tapped nut J
carried by a saddle or bracket K bolted to the said cover.
The hollow piston G has openings or ports L made near its upper end through
which the tar and liquor flows from the interior of the vessel A into the pipe F and
thence away from the plant the depth of seal in the main B above the bottom of
the dip pipe M being regulated by the height of the undersides or lips of the
openings above the bottom of the pipe M. The spindle H regulating the
position of the piston has a scale marked upon it as at N Figure 3 which in con-
junction with the pointers O secured to or formed on the bracket K indicate the
depth of seal or whether the main is empty which it is when the piston G is
screwed down until the ports L are opposite the upper end of the branch F'.
When the ports L are below the level of the upper end of the branch F1 and the
underside of the cover G is screwed down against the upper edge of the said branch
the hollow piston G is out of action.
The improved apparatus constructed as herein before described thus possesses the
following advantages. First, it provides for accurate adjustment of the depth of
seal above the bottom of the dip pipe M. Second, it enables the hydraulic main
to be flushed or emptied at pleasure and Third by screwing down the hollow
piston until its cover G' bears upon the upper end of the branch F' communi-
cation between the main B and the pipe F is shut off and by removing the flange P
on the end of the pipe access can be had for the purpose of cleaning out the

page_text: same and that without the employment of any stop cocks and without interfering
with the regular working of the main also by removing the cover of the vessel A
and weighting down the piston G access can be had to the interior of the vessel.
The vessel A is furnished with stop cocks a, a, at its lower end for the admission
of steam or hot water when required.
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. As apparatus in conjunction with the hydraulic mains of gas works plant
and analogous mains or pipes a vessel connected to said main and having secured
to its lower end a tee pipe the vertical arm of which extends into the vessel
and has a vertically operating hollow piston fitted tar and water tight to its upper
end said piston having ports communicating between the interior of the vessel
and the vertical branch of the tee pipe and being capable of adjustment to
regulate the depth of seal in and to empty the main and to shut off communi-
cation thereof with the discharge pipe F without the use of stop cocks substantially
as described with reference to the drawings annexed.
2. In apparatus of the class set forth the combination of the vertical stand
pipe F within a vessel communicating with the main and a hollow piston adjustable
vertically on said pipe and having ports therein the said combined piston and pipe
acting to regulate the depth of seal within to empty the main and to shut off com-
munication therewith without the use of stopcocks substantially as described with
reference to the appended drawings.
Dated this Thirtieth day of December 1891.
CRUIKSHANK & FAIRWEATHER,
62, St. Vincent Street, Glasgow, Agents.