AN IMPROVED METHOD OF TAPPING MAINS UNDER PRESSURE AND APPARATUS THEREFOR
Year: 1885

page_text: I, OSWALD BROWN, of 27 Great George Street, in the City of Westminster,
Civil Engineer, do hereby declare the nature of said invention for " AN IMPROVED
METHOD OF TAPPING MAINS UNDER PRESSURE AND APPARATUS THEREFOR" to be
as follows:-
:-
According to one method commonly in use for tapping mains under pressure, the
cock, after having been screwed into the main, has its plug horizontal and is not
readily accessible for the purpose of controlling the supply. Further, the size of
the hole bored in the main is frequently considerably smaller than that of the
service pipe to be connected.
Other methods involve the use of apparatus of a cumbersome character and
imperfectly adapted for use with high pressure.
My invention is designed to overcome these defects; and in applying the same
I proceed as follows:-
Beneath the pipe to be tapped I pass a U-shaped piece, which may be of cast
metal and ribbed both internally and externally. The two upper ends of the
U-shaped piece are suitably formed for engaging with the ends of a stiff cross-bar.
The cross-bar is provided centrally with a boss through which the stem of an
apparatus, hereinafter described, passes. The lower end of this stem is screw-
threaded externally and furnished with a nut; this nut being located between the
cross-bar and the top of the pipe. The lower extremity of the stem may be coned,
so as to fit a conical recess bored in the surface of the pipe; or the joint may be
made with the aid of a washer.
The recess is, by preference, cut before the cross-bar is applied. On tightening
the nut against the under side of the cross-bar, the end of the stem is forced into
the recess prepared for its reception in the upper side of the pipe; the cross-bar
being at the same time forced upwards against the engaging ends of the U-shaped
piece, the nut thus securing the three parts alluded to firmly in position and
making a tight joint between the pipe and the stem. The apparatus of which the
stem forms part consists of a vertical chamber provided with a valve seating,
which, by preference, I arrange horizontally and above which a horizontal branch
communicates. In this branch a valve is arranged in such a manner that it may

page_text: be projected forward and forced against the seating; or it may be retracted within
the branch. This valve is intended for temporary use during the operation of
applying the permanent valve, and may be subsequently removed; the service pipe
being ultimately attached to the horizontal branch. To the upper part of the
vertical chamber before referred to is temporarily applied a drill-chamber, having
at its upper part a stuffing-box through which passes a drill, and having at its side
a small, outlet branch-pipe and cock for the purpose of permitting a stream of
water to pass upwards through the drill-chamber during the process of drilling;
the metal borings being thereby discharged instead of passing into the main.
After the hole has been drilled, the drill is withdrawn to a sufficient height to
permit of the temporary valve in the branch being pushed forward and secured
upon the seating. The drill with its chamber are then removed and the permanent
valve with its stem and stuffing-box substituted in their place. The temporary
valve is then again retracted within the horizontal branch, whereupon the per-
manent valve is lowered upon the seat vacated by the temporary valve. The
latter is then removed and the service-pipe attached to the horizontal branch.
Instead of applying. a nut beneath the cross-bar to the stem of the valve
apparatus, the said stem may be screw-threaded through the cross-bar. Where
the method of construction first described is employed, the stem of the valve
apparatus and the hole through which it passes in the cross-bar are so shaped that
the former will not rotate in the latter upon the nut being turned.
It will be perceived from the foregoing description that, upon the completion of
the operations, the stem of the permanent valve is vertical and may be conveniently
worked by means of a box-spanner passed downwards through a surface-box, and
without disturbing the road itself. The initial direction of the service-pipe is,
bowever, horizontal.
Where the metal forming the substance of the main is of adequate thickness to
permit of a sufficient length of screw-thread being formed without piercing the
metal, it will be obvious that my improved connection with vertical valve spindle
and horizontal service outlet, may be attached without employing a clip, strap, or
U-shaped piece with cross-bar, as herein described.
ALL

page_text: An Improved Method of Tapping Mains under Pressure and
Apparatus therefor.
I, OSWALD BROWN, of 27 Great George Street, in the City of Westminster, Civil
Engineer, 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 :-
According to one method commonly in use for tapping mains under pressure, the
cock after having been secured into the main has its plug horizontal and is not
readily accessible for the purpose of controlling the supply. Further, the size of
the hole bored in the main is frequently considerably smaller than that of the
service pipe to be connected. Other methods involve the use of apparatus of a
cumbersome character and imperfectly adapted for use with high pressure.
My invention is designed to overcome these defects; and in applying the same
I proceed as hereinafter described, reference being had to the accompanying
drawings representative of three different stages in the process of tapping mains
under pressure and connecting the service pipe according to my improved method.
In Figure 1 is shewn apparatus applied to the main for the purpose of enabling
a hole to be drilled in the same whilst under pressure; in Figure 2 is shewn means
for temporarily closing the outlet from the main through the hole newly drilled
whilst the drill is being removed and the permanent valve installed in its working
position; and in Figure 3 the permanent valve is shewn closed and the service-pipe
attached, the temporary valve having been removed. Similar letters of reference
indicate corresponding parts in all the figures with the exception of the strap for
encircling the main and securing the connection thereto, an alternative design of
appliance for performing this function being represented in Figure 3..
Beneath the main a to be tapped, I pass a U-shaped piece b which may be of
cast metal, or, as shewn in Figures 1 and 2 it may consist of a thin strip of
malleable metal. Where the pipe is of considerable diameter the upwardly
projecting arms may incline inwards, as shewn in Figure 2. The extremities of
the arms are hook-shaped or otherwise suitably formed for engaging with the ends
of a stiff cross-bar e; through which passes centrally the stem d¹ of the permanent
valve-chamber d. The lower portion of the stem d¹ is screw-threaded externally
and furnished with a nut e located between the cross-bar c and the main a and
operating when tightened against the under side of the cross-bar to force the stem
end wise against the main. The lower extremity of the stem may be coned' and
a corresponding conical recess formed for its reception in the surface of the metal
of which the main is composed, this recess being by preference cut before the
cross-bar is applied. Instead of a conical joint, the stem may be flat-ended and
bear upon a washer, as shewn in the illustrations. The operation of tightening
the nut e forces the cross-bar c upwards against the engaging ends of the U-shaped
piece or strap b, and the stem d downwards upon the main a; the nut thus
securing the three parts alluded to firmly in position relatively to one another and
effecting a tight joint between the main a and the valve-chamber d.

page_text: The portion of the stem d'embraced by the cross-bar c is provided with a
feather & engaging in a feather-way formed in the cross-bar; or this portion of the
stem, as also the hole in the cross-bar, may be of elliptical or polygonal form for the
purpose of preventing the valve-chamber d turning with the nut e.
The valve-chamber d, of which the stem d' herein before described forms part, is
provided with a valve-seating d³, preferably horizontal, above which a lateral
branch communicates. The valve-chamber d is further provided at its upper
part with a branch d³ opposite to and concentric with the stem . To the
branch d' is fitted a drill-chamber f furnished with a blow-out cock g and provided
with a stuffing-box f¹ through which a drill h passes. The operation of the parts
is as follows: The drill h after having passed through the wall of the main a is
withdrawn clear. of the stem d¹; and, the branch d being closed, the blow-out
cock g is opened, thereby permitting a stream of water to flow upwards through
the valve and drill-chambers d and fand to escape through the said cock, the metal
borings being conveyed away with the water. I prefer however to keep the cock g
open during the process of drilling, the upward leakage of water preventing the
borings passing into the main.
The hole in the main having been drilled, the point of the drill h withdrawn into
the drill-chamber f and the valve-chamber d washed out as described, a ball-valve i
and wedge-shaped piece j, previously located in the branch d' of the valve-.
chamber d, are projected forward and arrivo above the valve-seating d³. This
operation is effected by means of mechanism mounted in a casing k, temporarily
attached to the branch of the valve-chamber; said mechanism consisting of a
valve-attachment engaging with the ball-valve i by means of a collared shank i¹
formed on the latter. The wedge-shaped piece j is provided with an extension and
a tail-piece through which a screw-spindle m works, the spindle being furnished
with an operating thumb-nut m¹ and a collar m² bearing against the body of the
valve-attachment and taking the back thrust of the screw-spindle m whilst
forcing the wedge-shaped piece j forward and the valve i down upon its seat d³.
The outer extremity of the valve-attachment is provided with a crutch-handle l
whereby the whole mechanism is moved longitudinally within the casing / and the
valve brought over the seating d³, or withdrawn therefrom and within the
branch d*.
The mode of operating the mechanism last described is as follows:--The position
of the parts being as represented in Figure 1 but the point of the drill h withdrawn
within the drill-chamber f, the spindle m, valve-attachment 1, valve i and wedge-
shaped piece jare pushed forward by means of the handle , the valve i arriving
above the seating d³. By means of the handle m¹ the spindle m is thereupon
rotated, and the wedge-shaped piece j moved forward until it arrives above and in
contact with the top of the valve i; the wedge acting to force the valve firmly
down upon the seating d³, thus closing the outlet from the main. Figure 2 shows
the position of the parts. at this stage.
The drill-chamber and drill h (Figure 1) may now be removed and the
permanent valve n (Figure 2) substituted; the latter being mounted in a body o
adapted for attachment to the branch d³ of the valve-chamber d. In Figure 2 the
permanent valve is shewn installed in position, ready for being lowered upon its
seating when the latter has been vacated by the temporary valvo i.
The wedge-shaped piece j is next retracted and the temporary valve i withdrawn
within the branch d'. The. valve n, by means of its screwed spindle n', is there-
upon shut down upon the seating ³, assuming the position represented in
Figure 3. The outlet from the main being now closed, the mechanism shewn in
Figure 2 as attached to the branch d may be removed and the service-pipe p
(Figure 3) attached in its place; the main being now tapped, connected and in
condition for ordinary working.
Instead of applying a nut beneath the cross-bar to the stem of the valve
Such a
apparatus, the said stem may be screw-threaded through the cross-bar.
modification is shewn in Figure 3, where c may be regarded as the cross-bar

page_text: formed with a boss c¹ through which the stem or shank of the cock screws, its
extremity seating in a recess formed in the outer surface of the main a The
U-shaped piece passing beneath the main is in this example constructed in two-
parts 6 bolted togother; the means for connecting the upper ends of these to
the cross-bar or top member of the encircling appliance also consisting of bolts.
It will bo perceived from the foregoing description of the manner in which my
invention is carried out that, upon the completion of the operations, the stem of
the permanent valve is vertical and capable of being conveniently worked by
means of a box-spanner passed downwards through a surface-box and without
disturbing the surface of the road. The initial direction of the service-pipe is
however horizontal, as usually deemed preferable.
Where the metal forming the substance of the main is of adequate thickness to
permit of a sufficient length of screw-thread being forined for the reception of the
tapping apparatus before piercing the metal, it will be obvious that my improved
connection with vertical valve-spindle and horizontal service-outlet, as also my
improved method of and means for drilling and connecting such mains, may be
applied without employing a clip, strap or U-shaped piece with cross-bar such as
hereinbefore described.
The clip b cross-bar c and nut e may also be employed for securing other forins
of connections to mains.
Having thus particularly described and ascertained the nature of this invention
and in what manner the same is to be performed, I declare that what I claim is
First. The improved method of tapping mains under pressure substantially as
herein described, such method consisting in securing the permanent valve-chamber
to the main by means of an encircling clip, passing a drill through the said
chamber and through the metal of the main, partially withdrawing the drill and
applying a temporary valve to the permanent valve-scating, removing the drill
and substituting the permanent valve, withdrawing the temporary valve and
applying the permanent valve in its place; removing the temporary valve from
the delivery branch and connecting the service-pipe in its stead.
Second. The improved apparatus substantially as described for tapping mains
under pressure, comprising the permanent valve-chamber with seating, beneath
which is a hollow stem for connection with the main and above which are top and
side branches, the former concentric with the stem for the reception of the drill-
chamber and subsequently for the permanent valve, and the latter for the insertion
of a temporary valve and application thereof to the main valve-seating and
subsequently for connection with the service-pipe.
Third. In apparatus for tapping mains under pressure, the use of a temporary
valve introduced to the main valve-chamber through the service-branch and
provided with means for securing same upon the main valve-seating during the
removal of the drill and the installation of the permanent valve in place thereof
and for subsequent application to the same valve seating, substantially as
described.
Fourth. As means for operating a temporary valve between the service-branch
and the valve-chamber and securing same upon the main valve-seating, the
combination with the valve i of the valve attachment wedge-shaped piece j and
screw-spindle m, these parts being capable of longitudinal movement through
the service-branch d', the wedge-shaped piece j having a further longitudinal
movement imparted to it by the spindle m, arranged and operating substantially
as set forth.
Fifth. For communicating between mains tapped under pressure and service-
pipes, the improved connection, substantially as herein described and having the
valve-spindle arranged vertically and the service-outlet horizontally.
Sixth. The improved clip or device for securing connections to mains, consisting
of a U-shaped piece or strap such as b engaged with the ends of a cross-bar c
through which the screwed stem or shauk of the connection passes and beneath

page_text: which a nut is applied to the said shank, the nut operating to secure the clip upon
the main and to make a tight joint between the latter and the connection,
substantially as described with reference to Figures 1 and 2.
Seventh. The modified construction of clip, substantially as described with
reference to Figure 3, and in which the stem of the connection is screwed through
the upper member of the clip, and, abutting against the main, effects results such
as specified in the last preceding claim.