densation of the gas and deposition of naphthalene, which in
time may be so great as to cause a stoppage in the pipe. Another
reason why the service should be at a good depth is that the
weight of any heavy road roller or any great load passing along
the road will then be less likely to damage the pipe.
Services are -usually made of wrought iron, and the tubes and
fitting comprising them, such as tees, bends, elbows, sockets, etc.,
should be perfectly cylindrical, with no ribs or flat places, and
internally as smooth as possible. The welding should be scarcely
discernible from the other parts, and the screw should be equally
deep throughout the thread. In laying wrought-iron pipes, the
coupling or socket at the end, which is supplied along with the
pipe, should always be removed and replaced after painting the
thread with white- or red-lead paint. All service pipes, when
laid in the ground, may be protected from the oxidising
influences of the soil, moisture, and air, by being encased in a
V-shaped or Ll-shaped wooden trough, and filled in with hot
pitch and sawdust, to preserve the pipes, and, in fact, make
them last more than double the time that they would if left
unprotected.
The service of iron pipe having been carried through until it
GAS SUPPLY FROM GAS-HOLDER TO METER, 59
has entered the house, a cock should be fixed, and thence a short
piece of iron pipe leading just above the level of the meter and
about a foot away from it. All meters should be fixed in posi-
tions where they will not be subject to rapid changes of tempera-
ture, but the place in which they are kept should not be so warm
as to injure the leather bellows of the dry meters. The meter
should be fixed on a wooden bracket attached to the wall
of a passage inside the house, where it can be easily seen, so
that any defect can be quickly noted and repaired ; it should
never be fixed in an inaccessible position, nor in a small cup-
board with other things, for if a leakage occurred the cupboard
would rapidly fill with a mixture that would instantly explode in
contact with flame. The meter, especially a wet one, should be
carefully put level, and fixed up with sufficient firmness to
prevent shifting of position.
CHAPTER IV.
LAYING GASPIPE IN THE HOUSE.
THE preceding chapters having been devoted to the consideration
of means and methods of supply, it is now convenient to deal
with the means and methods of providing for the consumption of
gas namely, with the materials and operations relating to domestic
gas-fitting. The requirements of the case having been ascer-
tained, and the scheme of service having been carefully planned
and arranged, measure up the lengths of iron piping required,
making due allowance for threaded joints, bends, elbows, or
tees. Bends should always be used where possible, as the quick
alteration in the direction of the flow of the gas in elbows causes
friction, and a consequent loss in the pressure obtained at the
burner end of the piping. Then mark off the length with a piece
of chalk, and fix the barrel in a pipe vice. Bends, elbows,
tees, and other small fittings are shown in Fig. 36. Pipe vices
are usually of the kind illustrated in Fig. 37, p. 63. The next pro-
ceeding is to hang the pipe-cutter on the pipe. The pipe cutter
is a claw-shaped tool, with one or more hard steel cutting discs
on the inside which can be made to screw in and out. A one-
wheel cutter is illustrated by Fig. 38, p. 64 ; a three-wheel cutter by
Fig. 39, p. 64 ; and two patented shapes of three-wheel cutters by
Fig 5. 40 and 41, p. 64. Screw up the handle of the cutter until
the wheel is exactly on the chalk mark, and give the cross-
bar a slight turn so as to make the cutter-wheel enter the
iron a little. Having put some oil where the cut is to be
made, turn the pipe-cutter round the pipe once or twice,
and take another slight turn on the cross-bar, continuing
in this way until the pipe is cut through. A little oil on
the cut assists greatly in the severing of the pipe, and, while
saving the wear and tear on the wheel, also lessens the labour of
turning the apparatus round. Several shallow cuts are much
better than a few deep ones, as the deep cuts cause on the ends
of the pipe a considerable ridge, which must be filed off before
the dies can be used for threading; and as the thread at the end
LAYING GASPIPE IN THE ROUSE.
61
of the pipe has to be made somewhat smaller and tapered, this
ridge is especially objectionable. Having cut the pipes to the
required lengths, it will be necessary to put the threads on them
so that a gas-tight connection may be made with the sockets
(see Fig. 36) which are obtainable ready screwed.
Fixing the pipe as before in the pipe vice, with a few inches
of the end which is to be screwed protruding, pass a file round
a i
REDUCING SOCKET!
NIPPLE
UNION ROUND ELBOW TEE ELBOW CROSS
SHORT PIECE
LONG SCREW
SPRING T&^ BEND
. oG. Tubes and Fittings.
the edges of the end to remove the burr caused by the cutter, and
continue the filing until the portion of the pipe to be threaded is
of even diameter.
The following table shows the dimensions of Whitworth's
standard gas threads, with particulars of the diameters at the
top and bottom. These threads are always used for gas and
water pipes. The vulgar fractions in the third and fifth columns
of the table are not exact, being to the nearest ^in. only.
PRACTICAL GAS-FITTING.
DIAMETER OF PIPES IX INCHES.
Internal.
External.
At Bottom of Thread.
THREADS
PER
INCH.
i
3825 '336 28
i
518 M '451
19
g
'6563 H
'589 i
19
825
11
734
J ,
14
1
9022
5 7
IT*
811
iir
14
I
1-041
1*
949
64
14
i
1-189
ITF
1'097
14
1
1-309
1
1192
I- 5 -
11
It
1-492
H b
1-375
If"
11
H
1'65
114
1-533
11
11
1-745
if
1-628
1 L
11
it
1-882
IF*
1-705
11
H
2*022
2gL
1-965
ill
11
if
2-16
2/Y
2-042
11
i|
2-245
24;
2-128
2g
11
2
2-347
li
2-23
2j
11
at
2-467
^3T
2-351
2||
11
2j
2587
2 fi
2-47
11
2|
2-794
24i
2'678
9A
11
24
3
3
2*882
0.52
^ A 4.
11
at
3-124
31 :
3-009 3"
Jl
2 L |
3-247
3|
3-13 3J
11
21
3-367
3f
3-251 3i
11
3
3-485
3- 1
3-368 3|
11
31
3'698
3M
3581 3
11
31
3-912
2ia
3'795 3^1
11
3f
4-125
4| 2 4-008 4"'
11
4 4-34 4H 4-223 4}
11
Three kinds of stocks and dies are in use for screwing the
pipes. Those that are most commonly employed are the
straight stocks and dies, as shown in Fig. 42, p. 65. These can be
made to perform all the operations of which the others are
capable. The taper die-stocks (Fig. 43, p. 65) are quicker to
work, for they give a full thread at one threading, and, unlike the
straight dies, these have guides which keep them square when
starting the screwing of the pipe. This is a great advantage, as
connections on which the threads have not been properly and
LAYING GASPIPE IN THE HOUSE.
63
squarely made are very unsightly. Again, with the taper
dies the two halves of the dies are tightened together before
commencing the screwing, whereas with the straight dies the
two halves have to be opened sufficiently to allow the pipe to
enter between, and, when straight, must be screwed up gradually
as the thread is being made on the pipe.
If the thread is not exactly straight at the start, the remainder
of the work will be thrown still further out. To avoid this mishap
place the pipe vice on the edge of the bench, and fix a pipe in it,
screwing down the vice so that the pipe is at right angles with
the face edge of the bench ; then the stocks and the dies can be
held horizontally, and it can be easily seen whether they are
parallel with the edge of the bench.
PRACTICAL GAS-FITTING.
Fig. 38. One - wheel Pipe - cutler
Fig 1 . 39. Three- wheel Pipe-cutter
Figs. 40 and 41. Improved Three
wheel Pipe-cutters.
LAYING GAS PIPE IX THE HOUSE.
65
br.
Having inserted the pipe
end between the two halves
of the dies so that the end
of the pipe is about flush
with the face of the dies,
screw up with the hand the
handle of the stock as tight
as it will go, and then, in-
serting a short bar into the
hole in the handle, give it
about an eighth of a turn
more ; this will cause the
dies to s'ightly enter the
iron. Next thoroughly oil
the dies and the pipe to be
cut, and take a steady turn
or so with the stocks so as
to start the threading, when
the dies may be tightened
slightly more. In this oper-
ation, as in cutting pipes,
avoid deep cuts, which tend
to wear out the dies, whilst
the thread cut is not nearly
so clean ; and care must be
taken that there is always
a good supply of oil at the
cutting point. It is desirable
to give the thread a slightly
taper shape, and this is done
by slightly and gradually
tightening the dies as the
stocks are worked off the
thread. In turning round
the stocks take half a turn
and then go back, say one-
eighth of a turn, so as to clear
the dies and allow the cut-
tings of metal to get into
the grooves made in the
dies, and thence to fall out.
6ti PRACTICAL GAS-FITTIN.G.
It is better to tighten up the dies at different parts of the
thread and at different parts of the turns, so that the deeper
cutting in of the thread shall not commence always in the same
place. The error indicated is one which the gas-fitter is very apt
to commit, as he usually places the short lever in the same place
each time he uses it, and consequently stops at the nearest points
of the turn to this place when he again wishes to tighten up the
dies. When the thread is considered to be cut sufficiently deep
to allow a socket to fit on it, the dies must be either run off by
turning the stock round, or else the handle must be loosened,
when the dies can be opened out. It is well to have a socket or
tee of the right size ready at hand to test the size of the thread,
the said pipe having about six to eight threads on it, thus
ensuring a really good joint. One of the great advantages of the
taper dies is that the threads are certain to be cut down to the
proper size at the first operation, so that the stocks have never to
be placed again upon the thread, as is the case with the straight
dies. Straight dies, however, must sometimes be put on the
thread again, to reduce the diameter of the thread, and then
great care must be taken that they are put into the old threads,
or new threads will be cut on the old ones, and consequently
the whole thread ruined. To avoid such a disaster, proceed .as
described on p. 63 for first putting on the stocks, by holding them
parallel to the edge of the bench.
The third method of screwing pipes is that by means of a
screwing machine ; this is usually made with adjustable dies,
which not only effect a considerable saying in time, but ensure
much better and much more even work than either of the two
methods already described. Unfortunately the machine is not
very portable, but in a workshop where sufficient pipe- screwing
is done to justify the purchase of the machine, it is most valu-
able, as, during periods of slackness odd portions of piping can
by its means be screwed and made into nipples, short pieces, or
connectors ; in fact, in some shops it is usual to keep a boy
constantly employed on such work.
The screwing machine shown in Fig. 44 needs but little
explanation. The pipe is fixed in the vice and tightened by the
screw shown at the top of the figure ; the end of the pipe is
then brought close to the dies by means of the arms at the
side, which actuate a pinion that gears fnto a rack on the
under-side of the vice. When the pipe has entered the dies,
LAYING (J AS PIPE IN THE HOUSE. 67
which are tapered, and should be set to the exact size of the
thread required, the handle that gears with the disc containing
the dies is turned, the dies cutting their way gradually into the
pipe until the thread is completely formed, whilst the pipe is
drawn gradually into the dies. A large number of these
machines are also fitted with a cutter, which can be used for
dividing the pipes into the lengths required. Some of these
machines are so arranged that there is no backing off the dies
when the thread is finished ; all that is necessary being to open
out the dies and run the pipe vice back.
Fig. 44. Screwing Machine.
The joints in the iron pipes are usually made by threading
externally the ends of the pipes and fixing sleeves or collars, or
sockets as they are usually termed, on these ends, the sockets
being threaded internally to suit the thread on the pipes ; and
for ordinary purposes this joint will be all that is required. But
there are occasions as, for instance, when two outlets are
required somewhat close together when some other means will
be desired, and then the common method is to put in what is
called a nipple, which is nothing more than a H in. length of
pipe, threaded externally from end to end (see Fig. 36, p. 61).
This, having been painted, is screwed half-way into one of the
tees, and then the other is screwed on to the remaining half, a
38 PRACTICAL GAS-FITTING.
few strands of yarn being twisted round the joint before it is
screwed up tight. This is by no means the only way in which
the nipple is useful, but will serve as an example of the ordinary
method of employing it.
There are several kinds of pipe tongs in common use, but
Fig. 45 shows the one generally employed. Some are made with
a screw so as to suit several sizes of pipes ; a parrot-bill pipe
wrench is shown by Fig. 46. The professional gas-fitter will
require a complete set of pipe tongs, and when purchasing these,
care should be taken to see that they are of good quality and
strongly made, otherwise they will be in frequent need of
straightening.
The screwing in of the nipple is sometimes a matter of
difficulty, especially when the nipple, or the tee, or the elbow,
has become slightly rusty. The common method of screwing is
to fit the nipple into the proper dies, clamping them tight on the
Fig. 45. Pipe Tongs.
half that will be left outside the first tee, thus holding the nipple
securely without the threads. But the time taken in getting the
proper dies into the stocks and screwing them up again into the
nipple is considerable, and consequently an impatient or careless
workman is liable at times to use his tongs on the thread, which
may be ruined thereby. The thread is slightly injured even
when the stocks and dies are used, as the cutting edge of
the die is sure to enter the metal to a greater or less degree,
according to the amount of pressure applied to the lever
for tightening the dies round the nipple. A comparatively
new appliance, called the Ashley nipple-holder, obviates all
these defects. Sockets of different sizes are provided, into
which one half of the nipple is screwed ; when it is sufficiently in,
a plunger is forced into contact with the edge of the nipple, and
the teeth on the plunger enter into the metal where they can
do no damage, but at the same time they prevent the nipple
turning and ensure its entry into' whatever socket is ready
for it.
LAYING GASPIPE IN THE HOUSE. 00
The connector is a joint of very great use, and should be
employed far more frequently than it is, especially where
extensions or alterations are at all likely. The connector costs
rather more than the socket, but is of great value when
from any cause piping has to be taken up. The few pence
expended on its purchase will be repaid the first time a leak
occurs or that the piping has to be cut to fix a connection
for, say, a gas stove or an extra light. As pointed out
on p. t>6, with reference to the screwing machine any short
pieces which may remain from the cuttings in the shop can
quickly be made into connectors, which are simply short pieces
of pipe externally threaded at both ends, but with the thread at
one or both ends cut sufficiently far to allow the ordinary socket
and a back nut to be screwed wholly on to the piece of pipe.
The great advantage of the connector is that by its use certain
Fig. 46. Pipe Wrench.
lengths of pipe can be screwed up together, and bends and tees
fitted on and connections led from them, and these can afterwards
be joined together by means of the connector. This advantage
is best appreciated when the gas-fitter is working in close
quarters or in awkward corners.
The pipes having been cut and joined up at the far ends to
the fitting or supply, a connector is chosen of the exact length
to go into the space between the two pieces of pipe, and the 1 ack
nut and socket are screwed right up on the connector, the other
end of which is then screwed in the ordinary manner into the
socket of one of the pipes ; and then the end of the other pipe is
brought exactly opposite the free end of the pipe. When this is
on tight, the back nut is brought close up to the socket, and
after a few strands of yarn have been wrapped between, is
screwed up quite tight against the socket, thus effectually
preventing any escape of gas, which would otherwise take place
owing to the socket being somewhat loose on the pipe forming
the connector. Paint made as described on p. 57 is required
on the connector as well as on all other joints in iron piping.
70 PRACTICAL GAS-FITTING.
The chief points to be observed in the manipulation of iron
tubing having now been dealt with, it will be convenient, before
treating of special fittings, to describe the use of composition (or,
as it is usually called, compo.) pipe, which is made from an
alloy of tin, lead, and antimony, the proportions varying greatly.
In making the pipe, the alloy is placed in a reservoir or con-
tainer over the piston of a hydraulic press, so arranged that it can
be heated by an annular fireplace. The reservoir is filled with
molten alloy by a spout through an aperture in the top ; when the
reservoir is full the spout is taken away and the orifice closed
tightly by an iron plug kept in position by an iron key. A steel
die fitted at the tpp has in it a hole of the size of the outside of
the compo. pipe, and this regulates its external diameter, the
internal diameter of the pipe being determined by a mandrel,
which passes directly through the centre and is moved upwards
Fig. 47. Method of Jointing- Compo. Pipe.
by the rising piston, the semi-fluid metal being at the same time
forced through the die. The metal cools down as it is forced
away from the foot of the mandrel and cone, until at a certain
distance it becomes sufficiently cool and hard to be coiled round
a drum.
In the first place, it is desirable to describe the usual method
of connecting the compo. pipe to the end of the iron tubing.
The end of the iron tubing having been screwed in the usual
way, a union, made of brass, is fitted to it ; these unions are of
two kinds, the barrel union and the cap and lining union. The
barrel union consists of a sleeve of brass tubing, with an internal
or socket thread suitable for screwing on to the end of the pipe,
and a short outside or spigot thread at the other end of the
sleeve, on which screws a hollow nut which serves to draw up a
second sleeve of brass, which is usually tinned. The hole at the
LAYING GASPIPE IN THE HOUtiE. 71
top end of the nut is smaller than that where the thread is, and
this prevents the collar on the second sleeve from passing
through, a gas-tight joint being made by means of a ring of
leather between the collar and the nut.
The cap and lining union is similar, except that in this the
nut screws directly on to the iron piping and the first-mentioned
sleeve is not required. It having been ascertained that the union
will fit the iron tubing, the union should be removed, and re-
tinned so that the solder may quickly join to the metal ; the
tinning done by the makers is rarely sufficient to ensure a
good gas-tight joint. In re-tinning with a soldering-bit, the sleeve
is held on its side by a pair of pliers or pincers, and the sleeve
having been well powdered with resin, a hot soldering-bit is
passed round it until the solder has run all over the part that
will afterwards be required to be joined to the compo. pipe,
Fig-. 48. Shave-hook.
plenty of solder being kept on the bit. When the re-tinning is
done by means of a blowpipe, the solder is made to flow round
the sleeve in the same manner, a spear of flame being directed on
to the solder and on to the part to be tinned. By this means a
smooth and at the same time thin layer of solder is run over the
sleeve, which will quickly make a joint with the solder used
when the joint itself is being made. The methods of using both
soldering-bit and blowpipe are described in detail below.
Joints between compo. and lead pipe, or between two pieces
of compo., or between either of these pipes and brass piping, can
be made in either of the two ways just described that is, with a
well-tinned soldering-bit or with the blowpipe. In joining two
pieces of compo. pipe of equal size, it is usual to turn the one end
of the compo. pipe until it points directly upwards, then, with a
plumber's top(B,Fig. 47), usually made of boxwood, the endis opened
by lightly tapping the top with a hammer, or simply by twisting
the top, keeping a pressure downwards on the pipe, taking care to
hold the compo. pipe just below the part being opened out (as at A,
72 PRACTICAL GAS -FITTING.
Fig. 47). The pipe should be made sufficiently large at the end
to just allow the end of the other piece to be inserted in it.
Then the opened end should be cleaned with a scraper (Fig. 48,
p. 71), or with a penknife. The scraper, which is really a plumber's
shave-hook, is also of use in cutting off the length of pipe required
from the coil. Having cleaned the inside of the opened end, cut
off the top edge cleanly, and carefully clean and scrape the end
that is to be inserted for about in. up, scraping off more near the
end, so that it is slightly bevelled (c, Fig. 47, p. 71). Put it into
the opened end, and, holding one piece in each hand, force them
tightly together until they hold of themselves. A little powdered
resin and oil, mixed, is put into the joint to act as a flux. This
mixture is prepared by melting resin in a ladle over a fire and
adding any common oil to it, and well mixing, taking care that
it does not become too thick. If a blowpipe be used and this
is certainly the quickest method the solder required is specially
prepared, and is known as blowpipe solder. If a spirit blowpipe
is not available, an ordinary mouth blowpipe, also some rushes
soaked in tallow, or an ordinary tallow candle, may be employed.
The rushes or candle are held in the left hand, the mouthpiece of
the blowpipe is placed in the mouth, and a strip of solder is held
in the right hand. Blowpipe solder is made in thin sticks, so as
to be more readily heate'd and bent close to the point at which it
may be required. Such blowpipe solder should consist of two
parts of pure tin to one part of lead, while ordinary solder seldom
contains more tin than lead, and plumbing solder contains only
1 part tin to 2 parts of lead. A simple test for the quality of
solder is to bend the stick close to the ear, when, if the solder be
good that is to say, if it contains a fair proportion of tin a
distinct crackling will be heard ; whereas a common solder will
bend without any noise at all. Having bent the solder so that
it will easily get into the joint, light the tallowed rushes, and
hold them a short distance from the solder ; with the blowpipe
blow a clear and steady blast, and so cause a small spear of flame
to stand out from the remainder. This spear will be of an intense
heat, owing to the excess of oxygen supplied. The point of the
blowpipe is kept about in. from the flame, which must be
directed on to the joint in process of making, the solder at the
same time being held against the joint until it begins to melt.
Hold the extreme end of the stick of solder in the spear of flame,
and dip it, when heated, into powdered resin until a small
LAYING GASPIPE I.V THE HOUSE. 73
quantity adheres to it. Now hold this resined end of the solder
close to the compo. pipe at the joint, and with the blowpipe and
rushes send a spear of flame upon it and the joint ; this will melt
the solder, and at the same time heat the compo. pipe sufficiently