US1601559A - Process and blank for the manufacture of middle rings of pipe couplings - Google Patents

Description

Sept. 28, 19260 J. CLARK PROCESS AND BLANK FOR THE MANUFACTURE OF MIDDLE RINGS OF PIPE COUPLINGS Filed July 19. 1924 Mount OJKM,

Patented Sept. 28, l926.

UNITED STATES PATENT OFFICE.

JAMES CLARK, 0F BRADFORD, PENNSYLVANIA, ASSIGNOR TO S. R. DRESSER MANU- FACTURING COMPANY, OF BRADFORD, PENNSYLVANIA, A CORPORATION OF PENNSYLVANIA.

PROCESS AND BLANK FOR THE MANUFACTURE OF MIDDLE RINGS OF PIPE COUPLINGS.

Application filed July 19, 1924. Serial No. 727,039.

My invention consists in the novel fea tures hereinafter described, reference being had to the accompanying drawing, which illustrates one embodiment of the invention selected by me for purposes of illustration, and the said invention is fully disclosed in the following-description and claims.

The object of my invention is to produce what is known as a wrought metal middle ring or coupling sleeve, of a rubber packed pipe coupling of the type illustrated in the United States Letters Patent granted to S. R. Dresser, No. 884,371, dated April 14, 1908, and which is used'in association with annular packing rings of rubber or other compressible material, and clamping rings, the latter being connected by clamping bolts to compress the packing engaging portions of the middle ring, and between such portions and theexterior walls of the pipe sections to be connected. These middle rings are provided centrally of their length and on their interior with an inwardly'projecting centering stop or rib located substantially centrally of the length of the ring and the end portions of the ring are provided with packing engaging portions usually formed by outwardly flared end portions of the ring. The usual method for the commercial production of these rings consists in rolling a skelp of wrought metal substantially like that illustrated in United States Letters Patent to George H. White, No. 922,990, dated May 25th, 1909, consisting of a flat bar having a longitudinally extending centrally located rib on one face and having its lateral edges inclined so that they converge toward the beaded or ribbed face of the bar. Sections of this skelp or bar of the required length to form blanks for invidual rings are cut 03 from the main bar and after being heated to cherry heat, are rolled or bent into ring form and the ends of the blank are united by welding. The ring so formed is then heated to cherry red, throughout, and subjected to the action of flaring devices which flare the marginal portions of the ring outwardly, so as to provide packing engaging portions to receive the usual packing ring. These rings are made in various sizes and it is necessary that they should be standardized to within allowable limits of variations as to their interior diameter in order that they may fit over the meeting ends of two adjacent pipe sections, to be united, with the least possible clearance consistent with due allowance for the slight irregularities in the exterior surface of the pipe sections with which they are used. It is customary, therefore, to subject these rings after the flaring operation to. the simultaneous action of internal and external dies under. hydraulic pressure, for the purpose of standardizing them as to sizeor internal diameter. It is found in practice that the rings vary considerably after the bending and flaring operations, on account of the variation in the stretch lengthwise of the metal blank, and the final step of standardization, has the effect of stretching the rings if they are-too small, or compressing them if they are too large, so as to bring them to standard size. This process is entirely satisfactory for the rings up to very considerable sizes in which the variation in the stretch of the blank is not too great to be corrected by the standardizing dies,

and for which there is a sufliciently large demand to make it commercially practicable to install the necessary standardizing dies without unduly increasing the cost of pro duction. In the manufacture of rings of this kind in exceptionally large sizes, for example, three feet in diameter and up wards, the variations in the stretch would be so great that it is doubtful if they could be corrected by the standardizing dies, and moreover, it would be prohibitive to make the necessary die equipment to standardize these rings. It is found in practice that the variations in the stretching of the blank due to the rolling operation is from one half to one and a half inches in the diameter of the ring, while the allowable limit of va.

riation is of an inch in pipes, for example, of four feet in diameter. In the manufacture of these large size rings, there fore, it has been the practice to cutthe blank a little longer than necessary, bend the blank, into ring form, weld the ends together, in any desired manner, heat the entire ring to cherry red, and subject it to the flaring devices to flare the end portions, ,with the result that a ring of proper form is produced which is considerably larger than the standard size. The ring is then carefully calipered around its internal periphery and the exact length for-the finished ring is 'measured and marked. The short section of excess length is then cut out, by making two cuts through the ring wall, the ends are brought together, and again welded over a mandrel of the proper size, which is of necessity collapsible, so that it may be Withdrawn from the ring after the final welding operation. This results in the production of a ring of the required size, but involves the cutting out of a section of the ring, and a second welding operation, and a waste of material, all of which add to the expense of production.

According to my present invention, I form a skelp or bar of a predetermined cross section, which will, when bent cold into ring form, produce the exact desired form of the finished ring. This bar or skelp can be formed by rolling at the rolling mills, by means of suitable rollers, or it can be formed by rerolling the skelp of the type illustrated in patent No. 922990 before referred to. A

section of this skelp of the exact length required to produce a ring of the desired size,

. is cut ofi from the special skelp bar, and is then bent cold into ring form so as to bring its meeting ends together. The ring is then welded, preferably by an electric welding apparatus, forming a bead weld upon a collapsible mandrel having its exterior diameter of the exact standard size desired for the internal diameter of the ring, thereby completing the ring by a single welding op eration, and dispensing with the flaring operation, and also with the necessity for outtingout a section of the ring and rewelding the ring which is required in the present methods of production. is removed from the collapsible mandrel and is of exactly the desired internal diameter within allowable limits of variation, and may thus be made more cheaply than the rings produced by the older methods, and of any desired standard size. My invention also embraces certaindetails of construction and operation hereinafter more fully set forth and claimed in the claims forming part of this specification.

Referring to the drawing which forms part of this specification Fig. 1 is a perspective view of a portion of a wrought metal skelp or bar from which the individual ring blanks are cut, one of such blanks being indicated in dotted lines;

Fig. 2 is an enlarged cross-section of the skelp or bar shown in Fig. 1;

Fig. 3 represents the ring blank bent into ring form and placed in engagement with a collapsible mandrel, illustrated conventionally, with its meeting ends abutted and unitedby welding; and

Fig. 4 is a view, partly in section, and partly in elevation, of a rubber packed pipe The finished ring coupling in which one of the finished rings is shown in operative relation with the packing rings, clamping rings and clamping bolts, and the connected pipe sections.

In carrying out my invention, I first preas indicated at 1, and is provided on one face with a projecting longitudinal bead. At equal distances on each side of the bead, 2, the skelp, which is of substantially uniform thickness is given a slight obtuse angular bend or deflection toward the beaded face of the skelp, as indicated at the dotted lines, 3, 3, and producing the angular portions, 4,

4, on opposite sides of the longitudinal center. The skelp is then given an angular bend, as indicated at the dotted lines, 5, 5, a short distance outside of the adjacent bend, indicated by thedotted lines, 3, 3, and from the bends, 5, 5, the skelp extends laterally in a horizontal direction, that is to say, parallel to the plane of the central portion, but

slightly out of alignment therewith, forming the flat portions, 6, 6. A short distance back from the marginal edges of the skelp, the skelp or plate is given a longitudinal bend, indicated at 7, 7, backwardly, or in a direction away from the beaded face producing the angular portion, 8, 8, having the beveled faces, 8 8, respectively. These beveled faces terminate in curved edge portions, 9, 9, which are connected to the opposite or unbeaded face of the skelp, by flat portions, 10, 10, parallel to the plane of the central portions, but disposed slightly out of alignment therewith, as clearly indicated in Fig. 2, in which continuations of the planes of the opposite faces of the central portions, 1, are indicated by the dotted lines,.

wy. It will be understood that the various bends indicated in Fig. 2,. extend longitudinally of the skelp or bar. The flat faces of the sections, 6, 6, indicated at 6, 6*, will form the interior walls of the pipe aperture at each end of the finished ring, as indicatedin Fig. 4, and it will be noted that the metal at each side of these pipe apertures, to wit, the portions, 4, 4 and 8, 8, extend in a direction away from the pipe in the finished ring,so that the central portion of the skelp .or bar has its inner face out of alignment with the faces, 6, 6 and this provides in the finished ring a certain amount of space or clearance, indicated at 11, in Fig. 4, which permits a slight angular movement of the pipe ends within the coupling sleeve, or middle ring, while the faces, 8*, will provide a conical packing recess to receive the packing rings of the couplings. As a result of this construction, to standardize these rings it is only necessary to bring the inner faces. 6?, 6 of the opposite pipe engaging portions of the rings to standard size as slight variations in other portions of the ring will not affect the operativeness thereof, while too great clearance at the opposite pipeiengaging portions would be very objectionable in that it vwould permit the packing to squeeze in too far, and if the diameter of the pipe engaging portions was too small, the pipe could not be inserted in the ring. Bymaking the skelp in the form shown and described, therefore,

I reduce the portions which have to be standv ardized to a narrow band representing the inner surfaces, 6, of the portions, 6, 6.

After forming the skelp or bar in the form previously described a section of this bar is cut off, as indicated by the dotted line 2 in Fig 1, to produce a blank of the length required to produce a ring of the desired diameter. This can be readily calculated,

1 and this blank or skelp section is thenbent,

preferably by cold-bending operation without heating, to bring it into ring form with its ends abutting, and with the head, 2, on the inside, as shown in Fig. 3. The ring is 1 then placed upon a collapsible mandrel 12, such as indicated in Fig. 3, having its exterior so shaped as to conform to the inner peripheral surface of the finished ring and to accommodate the central rib or bead, 2, and the abutting ends of the ring are welded, preferably by electric welding upon an electric welding machine, in any usual or desired manner, and while the ring is in contact with the mandrel, so that when the ring is formed, it will be of the desired standard size. Any desired form of collapsible mandrel can be employed. In Fig. 3 I have shown, more or lessdiagrammatically, a form of mandrel comprising an annularportion formed in segments, as indicated in the drawing, and forming anlannulus' havinga conical inner surface, thesegments being held in proper position by means of a conical plug, 12. This particular form of mandrel is known and need not be more. particularly described, and as'before stated, any other form of collapsible mandrel which can be withdrawn fromthe interior of the ring may be employed. After the welding operation' the mandrel willbe collapsed and withdrawn, in any desired or usual manner.

As only a small portion of the ring on either side of the weld is heated, and as the ring is preferably bent cold, there is little or no scale formed, and there is no considerable variation in the stretch of the metal of different rings. It is found in practice that rings can be made in this manner and brought to standard size within allowable 6 limits of variation which will always exist under any method of commercial manufacture of such articles.

In Fig. 4 I have shown the completed ring in association with a pair of packing rings 13, clamping rings 14, connected by bolts 15, and applied*to the meeting end portions of pipe sections,- indicated at 16-16, the adj acent end portions of which are held separated by the bead. 2, now formed into an annular centering stop on the inner face of the ring. It will be observed that the inner faces 6 of the portions 6 of the skelpprovide the pipe engaging portions at each end of the ring, as before stated, while the central portions 1 produce a cylindrical portion of slightly larger diameter, and thus enable the pipe ends to be accommodated without requiring them to be in absolute axial alinement as the clearance 11 permits slight angular positions ofthe pipe sections with respect to each other. The beveled portions 8 of the sections 8 of the skelp, in the finished ring produce the packing engaging recesses into which conical portions of the packing rings. extend, and it will be noted that the exterior faces 10 at each end of the ring form annular faces parallel to the axis of the ring over which the flange members 14; 5 v

.formed without the center rib, and the rings may be formed without centering stops if desired. Where the blank is rolled without the center rib on one face, if it is desired to provide the rings made therefrom with a centering stop, this may be accomplished by welding one or more projections in line with the longitudinal center of the blank, upon the blank before bending it into ring form,

or thefinished ring may be provided with centering stops by welding thereinone, two or more projections on the inner face of the ring.

It is also to beunderstood that the entire welding operation need not be performed while the ring is on the mandrel, as I may and I usually prefer to weld the meeting edges of the ring for short spaces. separated from each other, While the ring is so held. This is called tacking and is sufficient to hold the diameter or standard size of the ring correct. After such tacking the ring may be removed from the mandrel and passed on to other welders for finishing without the mandrel, by electric welding or otherwise, and preferably without reheating the entire ring.

What I claim and desire to secure by Letters Patent is j 1. The herein described process of forming standardized rings for pipe couplings, which consists in forming a blank of the required length when cold, to form a ring of the required standard size when its ends are ring form and bringing the ends together,

supporting the bent blank While cold on a standardized mandrel and bringing portions of the blank adjacent to the meeting edges them together in situ on the mandrel without materially heating the other portions of the blank.

2. The herein described process of forming a standardized middle ring, for rubber packed pipe couplings having a. centering stop, and an outwardly flared portion forming packing recesses, which consists in preparing a blank of wrought metal of the required length when cold, to form the ring of required standard size when its ends are brought together, the said blank being provided with centrally located projecting portions projecting from one face and disposed along a line extending longitudinally of and centrally of said face, said blank being also provided at each of its longitudinal edges with flared portions adapted to form the packing recesses when the blank is bent, bending the blank into ring form and bring- 'ing its ends together, supporting the bent blank while cold on a collapsible mandrel of standardized size, with its meeting ends inpos'ition to be Welded together and bringingp'ortions only of the. blank adjacent to said meeting edges to welding temperature and welding them together in situ on said standardized mandrel without materially heating the other portions of the blank.

3. The herein described process of forming a standardized middle ring for rubber packed pipe couplings having a centering stop and flared end portions forming pack- 1 ing recesses, which consists ir forming a 'blank of Wrought metal of a iength when cold to form a ring of the required standard size when its ends are brought together, said blank being provided with a centrally located longitudinal rib projecting from one face and longitudinally flanged edge portions adapted to foi'm'packing recesses when the blank is bent, bending the blank while cold into ring form and bringing the ends together, supporting the bent blank while cold on a collapsible mandrel with the end portions in position to be welded together, andbringing portions only of the blank adjacent to its meeting edges to welding temperature and Weldinu them together in situ on said standardized mandrel without mabrought together, bending the blank into only to welding temperature and welding terially heating the other portions of the blank, collapsing the mandrel and removing it from the ring.

4. The herein described process of forming a standardized fniddle ring for rubber packed pipe couplings, having a centering stop and flared end portions forming packing recesses, which consists in forming a blank of wrought metal of a length when cold to form a ring of the required standard size when its ends are brought together, said blank being provided with a centrally located longitudinal rib projecting from one face and longitudinally flanged edge portions adaptedto form packing recesses when the blank is bent, bending the blank while cold into ring form and bringing the ends together, supporting the bent blank while cold on a collapsible mandrel with the end portions in position to be welded together, bringing portions only of the blank adjacent to its meeting edges and at separated points longitudinally thereof to welding temperature and welding them together in situ on said standardized mandrel without materially heating the ot her portions of the blank, collapsing the mandrel and removing it from the ring, and completing the weld ing of the meeting edges of the blank.

5. The herein described process of forming a standardized middle ring for rubber packed pipe couplings, having a centering stop and flared end portions forming packing recesses, which consists in forming a blank of wrought metal of a length when 100 cold to form a ring of the required standard size when. its ends are brought together, said blank being provided with a centrally located longitudinal rib projecting from one face and longitudinally flanged edge por- 1 tions adapted to form packing recesses when the blank is bent, bending the blank while cold into ring form and bringing the ends together, supporting the bent blank while cold on a collapsible mandrel with the end 110 portions in position to be welded together, bringing portions only of the blank adjacent to its meeting edges and at separated points longitudinally thereof, to welding temperature and welding them together 115 without materially heating the other portionsof the blank. collapsing the mandrel and removing it from the ring and completing the welding of the ring by bringing only the portions thereof adjacent to the meeting 120 edgesof the blank to welding temperature and welding them together in situ on said standardized mandrel, without at any time materially heating the other portions of the blank.

6. The herein described process of forming a standardized middle ring for rubber packed pipe couplings, having a centering stop and end packing recesses,- which consists in forming a blank of Wrought metal of 130 a length, when cold, to form a ring of the required standard size, said blank having centrally located projecting portions disposed along a line extending centrally and longitudinally of one face thereof, and having on each side of said central longitudinal portions narrow longitudinal portions having their inner faces parallel to the general plane of the blank, but deflected out of alineoperation into ring form with said central projecting portions and said narrow longitudinal portions on the inner side of the ring, sup porting the bent blanks while cold on a collapsible standardized mandrel, having standardizing exterior faces to engage the inner faces of saidnarrow longitudinal portions of the blank, and bringing the meeting ends of the blank into welding relation, bringing portions only of the blank adjacent to said meeting edges to welding temperature and welding them together in situ on said standardized mandrel without materially heating the other portions of the blank, to form a standardized pipe engaging portion at each end of the ring between the central projections and the flanged portions thereof.

7. The herein described blank for a middle ring for pipe couplings consisting of a bar of wrought metal of the desired length to forin the ring, said bar having flat longitudinal central portions, and being provided on each side of said central portion with longitudinally extending narrow portions parallel with the central portions, but deflected out of alinement therewith in a direction toward one face of the blank and connected with the central portions by angularly disposed portions, the longitudinal marginal portions of theblank being bent in the op posite direction from said narrow longitudinally disposed portions, and forming a beveled portion at each longitudinal edge of thebla 8. The herein described blank for a middle ring for pipe couplings consisting of a bar.

of wrought metal of the desired length to form the ring, said bar having flat longitudinal central portions, and being provided on each side of said central portion with longitudinally extending narrow portions paral' lel with the central portions, but deflected out of alinement therewith in a direction toward one face of the blank and connected with the central portionsby angularly disposed portions, the longitudinal marginal portions of the blank being bent in the opposite direction from said narrow longitudinally disposed portions, and forming a beveled portion at each longitudinal edge of the blank, the opposite face of the blank being substantially parallel to the first-mentioned face except at the marginal portions thereof, where it is provided with longitudinal faces parallel with the flat central portions, but deflected out of alignment therewith in a direction away from the first-mentioned face.

9. The herein described blank for amiddle ring for pipe couplings consisting of a bar of wrought metal of the desired length to form the ring, said bar having flat longitudinal central portions, a centrally located longitudinal. rib projecting from one face thereof and being provided on each side of said central portion with longitudinally extending narrow portions parallel with the central portions, but deflected out of alinement therewith in a direction toward the ribbed face of the blank and connected with the central portions by angularly disposed portions, the longitudinal marginal portions of the blank being bent in the opposite direction from said narrow longitudinally disposed portions, and forming a beveled portion at each longitudinal edge of the blank, the face of the blank which is not provided with the rib being substantially parallel to the ribbed face except at the marginal por-- tions thereof, where it is provided with longitudinal faces parallel with the flat central portions, but deflected out of alinement therewith in a direction away from the ribbed face.

In testimony whereof I afiix my signature.

JAMES CLARK.

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