IMPROVEMENTS IN MACHINERY OR APPARATUS FOR MAKING PLUMBERS' TRAPS OR BENDS to be as follows:
Year: 1884

page_text: I WILLIAM HENRY DORMAN of The Old Brewery, Foregate Street, Stafford, in
the County of Stafford, Engineer, do hereby declare the nature of said Invention
for "IMPROVEMENTS IN MACHINERY OR APPARATUS FOR MAKING PLUMBERS'
TRAPS OR BENDS to be as follows:-
"
This Invention relates to the manufacture of plumbers' traps and bends of lead
or other material of the kind described in the Specification of former Letters
Patent dated 20th October A.D. 1875 N° 3646 and is designed to provide improved
apparatus for the manufacture of such traps or bends as hereinafter described.
In the Specification of former Letters Patent dated 19th November A.D. 1875
N° 4026 a machine is described which consists essentially of two hydraulic presses
with lead containing vessels and a pipe-forming die between the same, which
presses and vessels are held together in proper relative positions by screw-threaded
straining bars and nuts.
According to my present Invention I make a machine in which the two presses
are united by tension bars of the construction usual in hydraulic apparatus, but
I support the lead-containing vessels and die by frames carried upon tension-bars
and arranged to be adjusted with relation to the axis of the apparatus by means
of wedges resting against the said tension bars. The working strain upon the said
vessels and die is taken by pillars resting between the vessels and the ends of the
hydraulic cylinders. I also provide wedges between the ends of these pillars and
the vessels to tighten the pillars in their place. I am thus enabled to dispense
entirely with the screw-threaded straining bars and nuts described and shewn in
the aforesaid former Specification N° 4026.
Another part of my Invention consists in providing a loose ring or collar screwed
into the mouth of the die to form the exterior surface of the trap and a loose cap
screwed upon the core to form the interior surface. This loose ring and the cap
are made of rounded form in order to afford support for the lead. as it issues from
the die chiefly to facilitate the making of traps with a curvature of small radius.

page_text: A further part of my Invention consists in applying to the hydraulic cylinders
relief-valves to be actuated at the will of the operator for taking off the pressure
from either cylinder, as required, in order to facilitate the manufacture of traps of
small diameter and of sharp curvature.
Another feature of my Invention consists in providing two additional divisions.
in the die described in the said former Specification N° 3646 for the purpose of
supporting the core against the lateral strain brought upon it in transferring the
pressure from side to side in making bends first in one direction and then in
another:
Dated this 5th dor of Now 1001

page_text: I, WILLIAM HENRY DORMAN, of The Old Brewery, Foregate Street, Stafford, in
the County of Stafford, Engineer do hereby declare the nature of my Invention
for "IMPROVEMENTS IN MACHINERY OR APPARATUS FOR MAKING PLUMBERS'
TRAPS OR BENDS' 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 the manufacture of traps and bends of lead or other
material of the kind described in the Specification of former Letters Patent dated
20th October A.D. 1875, N° 3646, and is designed to provide improved apparatus
for the manufacture of such traps or bends as hereinafter specified.
Machinery for such manufacture is described in the Specification of Letters
Patent dated 19th November A.D. 1875, N° 4026; this machinery consists
essentially of two hydraulic presses or cylinders with lead-containing vessels and a
pipe-forming die between the same; these cylinders and vessels are held together.
in proper relative positions by screw-threaded straining bars and nuts.
According to my present Invention I introduce into such machinery various
improvements whereby I am enabled to avoid the necessity for the employment of
the said screw-threaded bars and nuts and to substitute therefor tension-bars such
as are ordinarily employed in hydraulic presses. And I support the lead-containing
vessels and die by frames carried upon these tension-bars and arranged to be
adjustable relatively to the axis of the cylinders as hereinafter set forth.
I also improve the construction of the die by providing it with a removable or
detachable ring or collar and cap.
Another feature of my Invention consists in providing, in the die described in
the said former Specification N° 3646, means for efficiently supporting the core
against the lateral stresses to which it is subjected in the working of the machine,
and I otherwise improve the said die and parts connected therewith as hereinafter
set forth.
A further part of my Invention consists in the employment of relief-valves to be
actuated at the will of the operator for reducing or taking off the hydraulic
pressure from either cylinder, as required, to facilitate the manufacture of the
traps or bends as hereinafter set forth.
My Invention is illustrated in the accompanying Drawings, in which
Figure 1 is a plan or top view of a machine for the manufacture of plumbers'
traps or bends.
Figure 2 is a side elevation of the same.
Figure 2a is a transverse section on the line x, x, Figure 1.
The remaining Figures, which are drawn to an enlarged scale, are hereinafter
described.
Like letters indicate the same parts throughout the Drawing; a, a, are two
hydraulic cylinders fitted with rams a¹ a¹; b, b are the usual tie-bolts or tension-
bars for supporting the said cylinders against the longitudinal stress to which they
are subjected; the said cylinders being formed with lugs a' and the bolts b with
collars as shewn. Between these two cylinders is placed the holder or receptacle c
for the lead or other material from which the traps or bends are to be manufactured.
In the following description, which refers more particularly to the manufacture
of lead traps, I term this part the lead-holder.
This lead holder is shewn detached in Figures 3 and 4, in longitudinal and
transverse section, and is further illustrated in Figures 5 and 6. It is made in three
parts viz-the central part c¹ in which the die c* is fixed, and the two cylinders c².

page_text: from which the lead is forced by rams hereinafter described through the said
central part and die.
The hydraulic cylinders a are supplied with water by suitable pipes and regulating
valves; d is the main pipe extending from the force-pumps to the stop-valve e and
thence to the regulator f. This regulator consists of two valves f¹f worked
preferably by a three-armed lever f³ so arranged that by means of the handle f
the operator can close either of the said valves at will and thereby regulate the
water pressure in the cylinders a, a, as required. From the regulator f the pipes g, g
extend to the outer ends of the cylinders to which they are connected at g¹, g.
These pipes are provided with stop-valves h, whereby the water may be shut off
from either cylinder to allow one to be, used independently of the other if desired.
The said pipes are also provided with other valves i, i which by branches ¹ com-
municate with the pipe for returning the water to the pumps in the usual manner.
These valves allow the water to escape from tlre cylinders at the completion of the
forward stroke or movement of the rams. In hydraulic presses where the cylinders
are horizontal and especially in working with lead, it is necessary that some
provision should be made for moving back the rams after the forward stroke or
movement thereof. I therefore construct the rams a¹ with pistons a* and admit
water into the annular space around the ram within each cylinder to act on the
forward side of the piston and thereby force the ram back. For this purpose I
connect the pipes to the main pipe d'at d' and to the cylinder covers at k².
for governing each cylinder independently this pipe is provided with inlet
stop-valves, and outlet valves m are connected to the waste-pipe by branches m¹.
The cylindrical parts c² of the lead-holder are bolted by their lugs c³ to strong
frame-plates n which are recessed at n* to fit upon the aforesaid tension-bars or
tie-bolts ; wedges or packing pieces n' are employed to permit the said frame-
plate to be adjusted to set the lead-holder truly in the axis or centre line of the
hydraulic cylinders.
And
In Figure 7 one of the said frame-plates is shewn in elevation in connection with
the tie-bolts and other parts.
The die-piece c¹ is made with projections at which enter corresponding recesses
or cavities in the parts c², so that, when the three parts c², c¹, c² are placed in
juxtaposition, they mutually support each other, and the entire lead-holder is
securely held and supported by means of the frame-plates n upon the tie-rods b.
It is, however, not sufficient to provide for sustaining the lead-holder in its axial
position and against lateral displacement only. It is necessary to provide also
against its endwise displacement, for, although the forces due to the hydraulic
pressure in the two cylinders act on the lead-holder in the same line in opposite
directions and therefore to some extent balance each other, yet in causing the lead
pipe (as it issues from the die) to bend alternately in opposite directions, the effect
of the force on the two lead-rams is varied so that the pressure preponderates on
first one and then the other end of the lead-holder. Therefore to prevent the
endwise displacement of the lead-holder. I employ the pillars o arranged between
the said frame-plates and the two hydraulic cylinders u. I prefer to employ three
of these pillars o for each end of the lead holder as shewn. These pillars at one
end (or at both ends) of the lead-holder are fitted with wedges o' to assist in bracing
the whole structure tightly.
I have found in practice that it is necessary, in order to prevent the lead from
forcing its way through the joints at c, to first wedge up the pillars o as tightly as
possible when the parts are cold, so that the pressure caused by the expansion of
the lead-holder when heated will act to keep the said joints tight.
The die-piece e has its nose or die proper made of a ring c and cap c7; I prefer
to have the ring c screwed into the die-holder c¹ and the cap c screwed upon the
core-pin or rod e8, so that the said ring and cap may be readily removed and
replaced when worn or injured, without sacrificing the entire die-piece. Moreover,
when it is desired to make slight differences in the size of the pipe or in the
thicknesses of the metal, the ring or cap or both may be changed without removing.

page_text: or changing the die-piece. The surfaces of the ring and cap are curved or rounded
to correspond with the curvature of the bend so as in some degree to support the
pipe as it issues from the die.
It will be seen that the core-pin c³ fills up the central portion of the chamber
in the die-piece leaving an annular space around it within the said chamber for
the passage of the lead. This annular space below the point co is divided by the
ribs or projections into two parts in which the streams of lead from the two ends
of the lead-holder are forced up to the die, being allowed to mingle or combine
only just before they reach the said die or nose. The said core-pin is turned.
carefully to fit the die-piece at c¹¹ and is secured by a screw nut as shewn or by
other suitable means.
I have found in practice that it is very important to have a very solid or firm
support for the core-pin c³, the said core-pin being subjected to severe lateral
stresses as the preponderance of pressure in working changes from one side to the
other side of the same.
In the machines described in the said former Specification N° 4026, the core-pin
is supported by ribs or projections arranged at right angles to the line of stress, but
the support afforded by this construction is very inadequate. I therefore construct
the die-piece c¹ with two supplementary ribs or projections c¹³ placed directly in
the line of action of such stresses, and thereby afford the most effectual support for
the core-pin against the same.
Figure 6 illustrates a modified construction whereby I am enabled to dispense
with the supplementary ribs or projections c¹³. For this purpose I form the
projections c so that they extend into longitudinal grooves in the core-pin.
It is obvious that, in making small lead bends wherein the cross-sectional area of
the metal is inconsiderable, a very slight movement of the lead-ram on either side
of the die will suffice to expel therefrom a considerable length of pipe. It is,
therefore, essential that the lead-rams should be so completely under control that
either of them will move or cease to move in immediate response to the will of the
operator in charge of the machine.
In using the machines constructed according to the said former Specification, the
aforesaid regulator has been relied on for controlling the movements of the two
streams of lead, that is to say, for alternately increasing and diminishing the
volume of lead issuing from the two halves of the die.
But I have experienced great difficulty with this apparatus in making small traps
with a sufficiently short or quick bend or curvature. I have, however, discovered
that this difficulty has been caused by the elastic resistance of the parts of the
apparatus to the very severe stresses to which they are subjected in working, that
is to say, the great pressure exerted by the hydraulic cylinders causes the parts of
the machine subjected to such pressure to spring or yield elastically under the
pressure, so that, when the regulator closes the passage to one cylinder and so cuts
off the supply of water to the same for the purpose of diminishing or stopping the
supply of lead to the corresponding side or half of the die, the elastic resistance and
consequent reaction of the strained parts against the stress is sufficient to cause the
ram (which to produce the desired result should at once become inoperative) to
continue its pressure on the lead so that the stream issuing from the said half of
the die is diminished too slowly to enable a short bend to be produced.
To obviate this difficulty I adopt a method of regulation whereby I effect the
immediate reduction of hydraulic pressure in the cylinders by means of relief-valves.
And I have shewn in the Drawings a convenient mode of carrying this part of my
Invention into effect for this purpose.
P, P are relief-valves arranged in connection with the working ends of the
cylinders a. These valves are provided with handles or hand-wheels p¹ arranged
in such a position that the attendant or operator in charge of the machine can
conveniently manipulate them and the regulator, that is to say, after stopping the
inlet of water to either of the cylinders a, he can open the corresponding relief-
valve and thereby immediately reduce the pressure upon the lead in the

page_text: corresponding half of, the lead-holder. Therefore, by properly manipulating these
valves, he can so regulate the two streams of lead issuing from the die as to give
any desired curvature to the traps or bends being formed thereby.
If it should be desired to dispense with the special relief-valves P, I may utilize
the valves i for this purpose.
Having thus fully described my said Invention and the manner of performing
the same I wish it understood that I claim
For the manufacture of lead or other traps or bends by hydraulic pressure
applied in opposite directions so as to force two streams of lead or other fnaterial
together and through a pipe-forming die.
C
First. The machine or apparatus in which the various improvements hereinbefore
described are incorporated and are combined with the cylinders and the other
ordinary parts of such machines; substantially as, and for the purposes, specified.
Second. The improvements relating to the supporting and staying of the lead-
holder and die in the proper position relatively to the cylinders by means of the
frame-plates mounted with a capability of adjustment on the tie-bolts or tension-
bars, and the pillars arranged in combination with the said cylinders and
frame-plates, and tightened between the same by wedges, substantially as, and for
the purpose, specified.
Third. The improvements relating to the construction of the die with a
removable ring and cap, or with either of these parts, substantially as, and for the
purpose, specified.
Fourth. The improved construction of the die-piece whereby I provide for
sustaining or supporting the core-pin against the lateral stresses due to the
variations or alternations of pressure on the two sides of the said core-pin,
substantially as, and for the purpose, set forth,
Fifth. The method of regulation for the purpose specified consisting in reducing
or letting off the hydraulic pressure on the rams in addition to controlling the
admission of the water to the same.
Sixth. The improvements consisting in the combination, with the aforesaid
cylinders and regulator, of the relief valves p to operate as, and for the purpose,
specified.
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7001