Improvements in Malleable Pipes and their Mode of Manufacture.
Year: 1888

page_text: Date of Application, 11th Sept., 1888
Complete Specification Left, 8th June, 1889-Accepted, 13th July, 1889
PROVISIONAL SPECIFICATION.
Improvements in Malleable Pipes and their Mode of Manufacture.
GEORGE HERBERT LLOYD Engineer Spring Hill Birmingham, do hereby declare the
nature of this invention to be as follows:-
In manufacturing plate and sheet iron and steel metal pipes for the conduit of
water gases,&c. it is generally necessary in pipes of large diameter that the pipe is
built up of many short pieces, these short pieces being connected by some form of
lap or butt-jointed riveted joint or by welding or lock-jointing but all these processes
are expensive. My invention consists in providing a better method of joining these
short pieces together than has hitherto been used, by expanding one piece into the
other and corrugating them, thus forming a stiff, firm and tight corrugated joint. If
a separate socket and spigot is used, the pieces carrying respectively the socket and
spigot can be expanded and corrugated into the socket and spigot. Thus if the longi-
tudinal seams are welded a complete pipe is formed with corrugated expanded joints
and (unless it was desired in special cases to put in an occasional rivet in the circum-
ferential joint for extra security) without the necessity of using any rivets whatever.
The pipe is made as follows:-The separate pieces are made in a usual manner with
longitudinal joints formed by welding, some sort of rivetting or other manner and
the one piece is forced for the required distance into the next piece, either by
shrinking on or forcing in and is then subjected to the action of a corrugating and
expanding press, by preference a hydraulic press acting from the inside of the tube.
The press may be conveniently carried on an arm with a certain amount of spring
such as would be the copper pipe which carries the water to the press and both the
head of the ram and the back of the Cylinder must be armed with a corrugating and
expanding tool and the whole pipe being carried between the jaws of a perfectly stiff
and unyielding machine-head in which are fixed tools to correspond with the corru-
gating tool on the inside of the tube, at each stroke of the press a portion of the tube
is corrugated on opposite sides when the press closes again the springing arm again
carries it so that the tube moves freely around it. If the tube be of sufficient diameter
to admit of a holder up of such size as to be absolutely rigid, the above process can
be done in an ordinary riveting machine or other press; the press then being outside
the tube and the corrugation then being made at one place on the tube at a time
only.
For a certain thickness of plate or sheet it might be more convenient to first corru-
gate the one piece before putting the second piece into it and afterwards expanding
the inner tube into the corrugations of the outer tube in the manner previously
described. If this latter process be adopted it is convenient to insert in the corruga-
tion of the outer tube lead or soft metal sheet or wire or other material which when
afterwards squeezed in corrugating the inside tube assists in making the joint tight.
Two corrugations running parallel round the joint make the joint in light pipes more
rigid than one only.
G. HERBERT LLOYD.
COMPLETE SPECIFICATION.
Improvements in Malleable Pipes and their Mode of Manufacture.
I, GEORGE HERBERT LLOYD, of Spring Hill, Birmingham, in the County of Warwick,
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:-
. In manufacturing plate and sheet iron or steel metal pipes for the conduit of water,
'gases, &c., it is generally necessary in pipes of large diameter for the pipe to be built

page_text: up of many short pieces; these short pieces being connected by some form of lap-
or butt-jointed rivetted, joint, or by welding or lock-jointing. All such processes
are, however, expensive. My invention relates to a better method of joining these
short pieces together than has hitherto been used; such method consisting in expanding
one piece into the other and corrugating them, so as to form a stiff, firm and tight
joint shaped as an annular corrugation. If it be desired that the pipe when built up.
should terminate in a spigot and socket ends, a socket may be separately formed and
attached to the main portion of the pipe by means of an expanded and corrugated
joint of the type before referred to, whilst the opposite extremity of the main
pipe may be formed as a spigot adapted for entering and being secured in such a
socket.
Assuming the longitudinal seams to be welded, a complete pipe is accordingly
- formed having corrugated expanded joints and (unless it be desired in special cases to
put an occasional rivet in the joints for extra security) without the use of any rivets
whatever.
In the accompanying drawings, Fig. 1 represents in vertical section a pipe composed
of several pieces of pipe united together according to my improved method; Fig. 2
being a similar view shewing a pipe to which a separate socket has been attached by
means of a corrugated joint. Fig. 3 is a view drawn to an enlarged scale illustrating
in section the construction of the improved joint; Fig. 4 being a similar view repre-
senting a longer joint specially adapted for use in the manufacture of pipes of light
metal. Fig. 5 is a diagrammatic view shewing, partly in side elevation and partly in
section, the corrugating and expanding apparatus employed in making the joints;
Fig. 6 being a corresponding erid elevation.
A pipe constructed in accordance with this invention is made in the following way:
The separate pieces a of the pipe A are produced in the usual manner with longitudinal
joints formed by welding, rivetting or otherwise. One piece is then inserted for the
required distance into the next piece, a tight joint being produced either by shrinking
on the latter or by forcing the one piece into the other. The parts overlapping at
the joint are then subjected to the action of a corrugating and expanding press
acting from the inside of the tube. A hydraulic press adapted for the purpose is
shewn at B, the same being conveniently carried by an arm b which may be solid or
tubular and slightly, flexible in character. In Fig. 5, the tube b₁ serves to convey
water for forcing out the ram; water being forced through the tube b² into the annular
space surrounding the ram for the purpose of causing it to recede in order to allow
the press to be turned or the tube to be removed. The head of the ram C and the
back of the cylinder (are respectively armed with corrugating and expanding
tools c and c¹ the pipe being carried between the jaws of a rigid machine-head D,
in which are fixed tools or shaping blocks to correspond with the forming tool or
corrugating surfaces enclosed within the pipe. At each stroke of the press, opposite
portions of the pipe are expanded and corrugated as the result of the pressure exerted
upon the interior and exterior surfaces. The press, when again closed, is so carried
by the yielding arm that the pipe may be freely moved. If the tube be of sufficient
diameter to admit a rigid supporting arm; the above-described process can be carried
out in an ordinary rivetting machine or press; the press being, under such circum-
stances, outside the tube, and the corrugating effect taking place at only one point
at a time.
With plates or sheets of a certain thickness, it is sometimes more convenient to
corrugate the outer piece before inserting the inner piece; the latter being subse-
quently expanded so as to occupy the corrugation formed in the outer piece in. the
manner herein before described. When this process of manufacture is employed it is
convenient to insert in the corrugation of the outer tube sheet lead or other soft metal
or wire or other material which, after being squeezed in the process of corrugating
the inner piece of tube, assists in making the joint tight. Two corrugations running
round the joint parallel with each other, as in. Fig. 4, make the joint more rigid than
when one corrugation only, as in Fig. 3, is employed; such construction being
especially suitable for pipes made of thin metal,
"

page_text: In Fig. 2, a socket a* is represented as being attached to the end-piece a¹ of the
tube A by means of a corrugated joint of the kind previously referred to.
Having now particularly described and ascertained the nature of this inven
tion and in what manner the same is to be performed, I claim :-
1. The manufacture of malleable metal pipes made up of short lengths jointed
together with lapped joints formed with one or more circumferential corrugations
substantially as herein described.
2. In the manufacture of malleable metal pipes made up of short lengths fastened
together with circumferentially-corrugated joints, the employment of a hydraulic press
carried by an arm extending into the pipe and acting in conjunction with shaping
blocks applied externally substantially as and for the purpose set forth.
3. In the manufacture of malleable metal pipes made up of short lengths fastened
together with circumferentially-corrugated joints, the employment of a hydraulic press
applied externally and acting in conjunction with forming tools carried by an arm
extending into the pipe, substantially as and for the purpose set forth..
Dated thin 8th day if Luna 1000
G. G. M. HARDINGHAM,
191, Fleet Street, London, E.C., Agent for the Applicant.
G. G. M. HARDINGHAM,
191, Fleet Street, London, E.C., Agent for the Applicant.