Improvements in and connected with the Testing of Drains and in the Apparatus therefor.
Year: 1896

page_text: Date of Application, Ist Dec., 1896
Complete Specification Left, 13th Apr., 1897-Accepted 24th July, 1897
PROVISIONAL SPECIFICATION.
Improvements in and connected with the Testing of Drains and in the
Apparatus therefor.
I, GEORGE LOW of 5 Bothwell Street, Edinburgh, North Britain, Plumber, do
hereby declare the nature of this invention to be as follows:-
This invention relates to improvements in and connected with apparatus for the
efficient testing of drains and has for its object an improved method of generating
smoke, an indicator, which is a device for indicating pressure on drains and all pipes
connected therewith while being tested. The method of generating the smoke
takes the form of a composition, which is composed of the following ingredients:-
75% of hard wood sawdust, 24% of saltpeter, 71% of ground pitch, 5% of rosin,
5% of sulphur, and 5% of cominon salt; the whole of the said ingredients are.
mixed together in a dry state and after being slightly heated are pressed into the
form of a block say 4" in height and 4" in diameter. This is ignited by means of a
fuse attached to the said block, after having been placed in a cast brass case, the
top of which is hermetically closed by means of a large thread.
When thoroughly ignited the composition smoulders and gives off a heavy
brownish yellow dense smoke. The indicator being constructed with hard wood top
and bottom, with pliable leather in between (in construction resembling the bellows
of a wind instrument) and the top when in action rises according to pressure put on
drains; on the top of the said indicator I place a face valve, which, when the seals
of traps being tested (as in the case of a light pressure test) are in danger of being
blown by too much pressure in the pipes, rises and so lets the superfluous pressure
escape.
When a heavy pressure test, on drains is necessary, the top of valve can be
weighted by means of leaden weights which will take a pressure of about 6 lbs. per
sq. inch, to raise the top of indicator to the height of 6 inches. Should the drain
pipes etc. be absolutely tight the pressure in the pipes, will prevent the indicator
from falling, but should there be a leak the indicator will fall according to their size
or number.
According to my invention I provide an air pump which is connected by a "tube
to the bottom of the cast brass case herein before mentioned; from the said tube I
connect another similar tube to which I fix the indicator by means of a lug coupling
to enable it when not in use to be disconnected and so be more conveniently carried.
Near the top of the cast brass case I connect a 14" tube for transmitting smoke
into drains. The whole of the above is contained in a galvanised sheet iron box for
protection say 12" long, 9" high and 8" broad.
The operation of the apparatus is as follows:-
To test a drain, remove the cover and place the charge (viz. the composition) into
the brass case, and light the fuse; when seen that this has taken good hold replace
the cover and commence pumping.
The current of air caused by so doing fans the now smouldering charge and forces
the smoke through the 14" tube hereinbefore mentioned, and thence into the drain
1:1 LL. Glad

page_text: All outlets are now stopped and as the pressure accumulates raises the indicator
hereinbefore described.
Dated this 30th day of November 1896.
JOHNSONS,
115 St. Vincent Street, Glasgow, Petitioner's Agents.
Improvements in and connected with the Testing of Drains and in the
Apparatus therefor.
I, GEORGE Low of 5 Bothwell Street, Edinburgh in the county of Edinburgh
.Plumber, 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 relates to improvements in and connected with apparatus for the
efficient testing of drains; and has for its object, an.improved method of generating
smoke, an indicator which is a device for indicating pressure on drains, and pipes
.connected therewith while being tested. The method of generating the smoke takes
the form of composition, which shall be composed of the following ingredients:-
75% hard wood sawdust, 2% nitrate, 7% ground pitch 5% rosin, 5% sulphur,
5% common salt. The whole of the said ingredients are mixed together in a dry
state and placed in a fire basket, and is ignited by means of a fuse placed at the
bottom of the charge with one end protruding through it as a convenient means of
lighting and is placed in a cast brass case the top of which is hermetically closed by
means of three thumb screws. The indicator is constructed with hard wood, top
and bottom, with threefold waterproof-cloth in between (in construction resembling
the bellows of a wind instrument); and the top when in action rises according to
pressure put upon drains. On the top of the said indicator I place a face valve,
which, when the water seals of traps being tested (as in the case of a light pressure
test) are in danger of being blown by too much pressure in the pipes, rises, and so
lets the superfluous pressure escape.
When a heavy pressure test on drains is necessary the top of valve can be
weighted by means of leaden weights to any pressure desired and has a lift of
5 inches. Should the drain pipes etc. be absolutely tight the pressure in the pipes
will prevent the indicator from falling; but should there be a leak the indicator
will fall according to there size or number. According to my invention I provide
a double action air pump which is connected by a "tube to the bottom of the cast
case herein before mentioned. From the said tube I connect another similar tube,
to which I fix the indicator by means of a coupling. Near the top of the cast case
I connect 1" tube for transmitting smoke into drains. The whole of the above is
contained in a galvanised iron box 14" long 8" high 7" broad.
The operation of the apparatus is as follows:-
To test a drain remove the cover and place the charge in the fire basket which is
afterwards placed in the brass case, then light the fuse. When sure that this has
taken good hold replace the cover and commence pumping. The current caused by
so doing fans the now smouldering charge and forces the smoke through the 1" tube
herein before mentioned, and thence into drain, which is quickly filled. All outlets
are now stopped and as the pressure accumulates, raises the indicator as herein before
described. To enable my invention to be fully understood I will describe the same
by reference to the accompanying drawings in which :-
Fig. 1 is a vertical section through A A on plan Fig. 1. A indicator, B cock with
bye pass C cast brass case to receive composition O double action air pump.
a face

page_text: valve. The dotted line a in C the fire basket and b the air spreader D thumb screws
all as herein before mentioned.
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 :-
1st. In drain testing apparatus a composition for generation smoke with a cast
case adapted to receive same and for the purposes herein before described.
2nd. An indicator for registering pressure and for the purposes herein before
described.
3rd A double action air munn used in drain testing apparatus