Search Images Maps Play YouTube News Gmail Drive More »
Sign in
Screen reader users: click this link for accessible mode. Accessible mode has the same essential features but works better with your reader.

Patents

  1. Advanced Patent Search
Publication numberUS693186 A
Publication typeGrant
Publication dateFeb 11, 1902
Filing dateApr 12, 1901
Priority dateApr 12, 1901
Publication numberUS 693186 A, US 693186A, US-A-693186, US693186 A, US693186A
InventorsFred D Sweet
Original AssigneeStirling Company
Export CitationBiBTeX, EndNote, RefMan
External Links: USPTO, USPTO Assignment, Espacenet
Mandrel for shaping hollow or tubular wrought-metal articles.
US 693186 A
Images(1)
Previous page
Next page
Description  (OCR text may contain errors)

, iff /7/ x n y 1 F.,n.- swan. MANDREL FOR vSHAPING HOLLOW 0R TUBULAB WROUGIHT METAL ARTIGLES., Y Appliention v:1mi Apr. 12,1901 (No Model.)

a' of Patented Feb. 11,. 19112.;

IdNr-run dSTATES PATENT OFFICE.l

FRED D. SWEET, OF PITTSBURG, PENNSYLVANIA, ASSIGNOR, BY MESNE AS- SIGNMENTS, TO THE STIRLING COMPANY, OF JERSEY CITY, NEWV JERSEY, A CORPORATION OF NEY JERSEY.

MANDREL For SHAPLNG HOLLOW ORIUBULAR' wRoUeHt-METAL ARTICLES.

srncrFIoATIoN-forming part of Letters Patent No. 693,1 se, dated February 11,1902.

application filed April 12, 1901. serial No. 55,508. (No modela To all whom it 71cm/ 0077/037471.;

Be it known that I, FRED D. SWEET, a resident of Pittsburg, in the county of Allegheny aud'State of Pennsylvania, have invented a new and useful Improvement in Mandrels for Articles; and I do hereby declare the following to be a full, clear, and exact description thereof. l

Myinvention relates to a mandrel for use in shaping hollow or tubular metal articles, such as serpentine boiler-headers and other art-ieles having an irregular shape.

Serpentine boiler-headers and similar articles are made from comparatively heavy metal, andas such articles are irregular in shape considerable difficultyv has been experienced in forming them of wrought-iron or steel. By reason of the thickness of the metal composing such articles it requires heavy pressure to properly shape the same, andfin order to prevent the Acollapse of the tube during the shaping process it is necessary to use an internal support or mandrel for the same. By reason ot the great irregularity in the shape of these articles difficulty has been experienced i-n providing a suitable internal support or mandrel which will offer sufficient resistance to the action of the external forging or pressing dies and which nevertheless is capable of being withdrawn or removed from the vh eader or other article after the same is shaped. Heretofore serpentine headers and similar articles have been made of Wrought metal only by the use of complicated sectional and collapsiblemandrels, which were inserted in the tube andv after the same was shaped were then collapsed and withdrawntherefrom.

It is the object of my invention to provide a mandrel for this purpose which is simple, strong, and comparatively'inexpensive and which can be easily inserted in the tube and withdrawn from the header or other article after the same has been shaped.

To this end it comprises a body or s upport of the proper shape Yto form the desired article and which is composed -of a few simple and easily-assembled sections so constructed that they can be secured together to form a tion of the same.

tion illustratingthermandrel shaped to form 6o .tubular articles of sharper" curve than illus- `trat'ed in Fig. 1. Fig..4 is a transverse secthe same. l

rigid body, which is inserted in the tube and is adapted to have the walls ofv the latter pressed down upon the same to shape the article, and which sections can thereafter be "readily withdrawn from the finished article. 51, Shaping Hollow or TubularVVrought-Metal alongitudinal verticalV section of my yim- VIn the accompanyingdrawings, Figure l is proved mandrel. Fig.y 2 is a transverse sec- Fig.,3 is a longitudinal section of the same. Fig. 5 is a plan view of either the mandrel shown in Fig. l or Fig. 3. Fig. 6 is a longitudinal sectional View of the man- 65 'drel formed in longitudinal sections to permit the application of a diaphragm to the header or other tubular article. Fig. 7 is a Fig. S is a longitudinal vertical section through 7o the shaping-dies, tube, and inclosed mandrel;

and Fig. 9 is a vertical transverse J:section of In the drawings Ihave shown my invention 'applied in the formation of serpentine boiler- 75 headers, and the mandrel comprises the body "l, havingsubstantially fiat andparallel side faces 2 and 'sinuous or corrugated top and bottom faces 3. This mandrel is adapted to be inserted in a rectangular tube 4, which 8o hastii'st been properlyA heated and, together with the same, is placed in the dies 5, whereby the tube is pressed down upon the mandrel to conform to the shape thereof, after which the said mandrel is removed. The dies 5 comprise a lower stationary die G, havinga 'sinuous working face 7v,jand an upper movable `die8, which is provided with a similar sinuous workingfaice -9,;.said upper die being moved, preferably, by means. of a hydraulic 9o cylinder (not shown) or by means of a cam, eccentric, or any other suitable mechanism. Formed integrally therewith or suitably secured tothe bottom die 6 is the plain-faced stationary side die 10, and opposite this is a plain-faced movable side die ll, ythe same being moved, preferably,'by meansV of a hydraulic cylinder or other equivalent mechanism, as above stated, although it may be moved by wedges or similar devices. In the Ioo operation of these dies the mandrel inclosed in the heated tube is placed on the bed-die 6, and the side die 11 is moved up to confine the same between said die 11 and the die 10, after which the die S is brought down to press the walls of the tube down into the depressions or corrugations on the upper and lower faces of the mandrel 1. In this operation it is necessary that the metal in the side walls of the tube between the points 12 and 13 be upset into the metal between the points 13 and 14, or, in other words, that the height of the side walls of the tube be reduced an amount equal to the distance between the points 12 and 13. In order to secure a proper upsetting of this metal and leave the side walls smooth and of uniform thickness, it is preferable that t-he side die 11 be at first brought but lightly against the side of the tube 4, and after the top die 8 has been brought down to upset the side walls of the tube the side die 11 is pressed firmly against the said tube, thereby smoothening out any bulges or unevenness in the side walls of the tube, and it may even be found desirable in carrying out the invention that the dies 8 and 11 be given alternate slight inward and outward movements in order to secure the proper shaping and upsetting of the side walls of the tube.l For this reason it is preferable that the side die 11 be moved by a hydraulic cylinder or equivalent mechanism, as above stated.

The invention so far described is not my own, but is the invention of James P. Sueddon, as described and claimed in applications, Serial Nos. 55,541 and 55,5t3, filed April 12, 1901.

My invention relates to the specific form of mandrel which is to be used with the dies 5 and in the manner above stated and will now be described.

My mandrel 1 comprises a series of blocks or sections 15 15 15" dac., all of which are similar and comprise the main body of the mandrel and two end blocks or sections 16 and 17, all of these blocks or sections being provided, preferably, with an opening or hole 18 passing therethrough, which when the blocks are assembled aline with each other to receive the tie-rod 19, the same being provided on one end with a head 20 and is screwthreaded at its opposite end to receive the nut 21, by means of which tie-rod and nut the said blocks are locked immovably together to form a rigid body. Itis obvious that in place of the tie-rod 19 and nut 21 various other means may be used to lock the blocks or sections together, and that my invention is not limited in this particular;

Each of the blocks 15 15a 15b, the., is of a general triangular shape having two iiat faces 22 and the third face being formed with the convex-curved portion 23 and the concavecurved portions 24 24. The end blocks 16 and 17 are so shaped that they will tit against the ends of the blocks 15 15rl 15", the., and

complete the mandrel, said end blocks 'being provided with straight outer faces, as at 25, to provide suitable seats for the head 20 and nut 21, as will be readily apparent.

In order that the blocks 15 15l 15", tbc., may be removed from the shaped serpentine header or other article, it is necessary that the faces 22 of said blocks should beara certain definite relation to the curved portions 23 2i thereof, as will now be explained. rllhe concave portions 21 of the blocks are struck about the points a a a2, dre., as centers, and the convex portions 23 of said blocks are struck about the points b h h2, the., as centers, and the said blocks are divided at the middle of the convex portions 21, as at 26. The points c c' c2 c3, dac., represent the points where the convex curves 23 merge into the concave curves 24:,and if through these points lines be drawn which are at right angles to both the radii 'a c and b c, such as the lines c d, c d', c2 d', c3 d2, c4 cl2, the., these lines will be tangential to both the curves 23 and 24:. The side faces 22 of the blocks are formed parallel to these tangential lines just specified. For instance, in block 15 the side face d e is parallel to the tangent c' d', and the face (lf e' of said block is parallel to the tangent c d ot' the same block, or, what is equivalent thereto, is a projection of the tangent c2 d of the block 15. By following this principle of construction the said blocks can be readily removed from the finished header or other article, it being impossible for the same to become bound therein. For instance, after the shaping of the header on the mandrel the tie rod 19 is removed, and after the blocks 16 and 15c are removed it will be apparent that the block 15 can be moved in a straight line in the direction of the arrow 26, and inasmuch as the face d. e' of said block is parallel to the tangent c d it will `be impossible for the block to be bound by the curved side walls of the header or other article. This principle of construction will hold good no matter what the shape or curvature or degree of curvature on the sinuous faces of the mandrel may be. In Fig. 3 the curves on the faces of the mandrel are shown much sharper; but it will be readily observed that the blocks nevertheless cannot become bound in the tube. In order, however, to facilitate the removal of the blocks, the apices of said blocks are removed, as shown at 27.

The corrugations 23 24C on the faces of the mandrel are shown as extending obliqu ely or at an angle across said faces, and the meeting lines 26 of the blocks will extend at the same angle as shown in Fig. 5. This is to adapt the mandrel to form headers for boilers having inclined water-tubes; but in case the header is to be used for a boiler having horizontal water-tubes the corrugations 23 2t and meeting lines 26 of the blocks will extend straight across the faces of the mandrel. The principle of constructing these blocks, however, will remain unchanged.

IOC

IIO

In certain forms of boiler-headers-as, for instance, in the Niclausse boiler-it is necessary to provide the same with a longitudinal diaphragm, and this may be done by forming the mandrel in two longitudinal sections,plac ing the shaped diaphragm between the same, inserting the mandrel-sections with the interposed diaphragm in the squared or rectangular tube,and then by means of the dies shown pressing the Walls of said tube down upon the mandrel, thereby shaping the header and also pressing the said walls firmly against the edges of the shaped diaphragm, and inasmuch as the latter is preferably formed slightly wider than the mandrel the edges thereof will become embedded in the Walls of the tube and be held firmly in place. This method is the invention of James P. Sneddon,as described and claimed in his application, Serial No. 55,542, iiled April 12, 1901, and I do not, of course, claim the same; but in Figs. 6 and 7 I have shown my specific form of mandrel adapted for carrying out this process. As shown, the mandrel is formed in two sections 28 28, each of which is formed of blocks constructed and assembled as shown in Figs. 1 and 3 and united by means of tie-rods and nuts, as in said figures. The diaphragm-29, Which'has been cut to proper shape and which is jogged or stepped, as shown at 30, in order to provide the faces 3l, which will be at right angles to the inclined Water-tubes of the boilers, is placed between the ksections 28 of the mandrel, and the latter are united, as by means of the links 32, which links are provided with openings at their opposite ends for receiving the tie-rods 19, by means of -which the sections 28 are secured together and prevented from endwise displacement. This man' 'said blocks can be-drawn out of the header.

The mandrel shown and described presents a perfectly rigidsupport to the thrust of the forging or shaping dies, and consequently insures the header or other article being properly formed on the same,there being no possibility that the article can collapse at one or more-points. At the same time this mandrel is so constructed that it is impossible for the sections thereof to become bound in the header or other article; but the same can be readily removed therefrom and can again bequickly and easily assembled and used in the formation of other headers.

While l have shown my mandrel applied in the formation of serpentine boiler-headers, I

Wish it understood that the invention is not limited thereto, but that the same can be applied in the formation of'other tubular metal larticles or shapes which are provided With at same comprising a body composed of a series of transverse sections and means for immovably securing said'sections together to form a rigid body, said mandrel being adapted to be inserted in the tube and have thelatter pressed thereupon and to be then removed therefrom. l

2. A mandrel'for usein shaping Wroughtmetal headers or other tubular articles, the same comprising a body provided with a curved or sinuons face and composed of aseries of sections and means for immovablysecuring said sections together to forma rigid body, said mandrel being adapted to beinserted in the tube and have the latter pressed thereupon and lto be then removed therefrom.

3. A mandrel for use in shaping Wroughtmetal headers or other tubular articles, the same comprising a body provided with oblique transverse corrugations and ycomposed of a series of sections, and means for immovably securiu g said sectionstogether to form a rigid body, said mandrelbeing adapted tov beinserted in the tube and have the latter pressed thereupon and to be then removed therefrom.

4. A mandrel for use in shaping Wroughtmetal headers or other tubular articles, the same comprising a body having a curved or sinuous face, said body being composed ofa series of sections the meeting faces of which are parallel to the tangents to the points where the concave curves merge into the convex curves, and means for securingsaid sections together.

5. A mandrel for use in shaping Wroughtmetal headers or other tubular articles, the

of a series'of sections the meeting facesof I IvoV whichare parallelto the tangents to the points Y where'the concave curves of the body merge into the convex curves,and means for se-` curing'said sections together.

6. A mandrel for use in shaping wroughtmetal headers or other tubular articles, the same comprising a serpentine body provided with oblique corrugations and composed of a series of sections the meeting faces lof which are parallel to the tangents to the points Where the concave curves of the'body merge into the convex curves, and means for securing said sections together.

7. A block for a sectional mandrelfor use in shaping Wrought-metalheaders or other tubular bodies, the same being vof substantially rectangular shape and having one side formed on concave and convex meeting curves, and two straight sides which are parallel to the tangents drawn through the meeting-points of the convex and concave curves on the firstnamed side.

8. A block for a sectional mandrel for use in shaping wrought-metal headers or other tubnlar articles, the same having dat parallel side faces and being substantially rectangular in shape, and having one side formed on concave and convex meeting curves, and two straight sides which are parallel to the tangents drawn through the meeting-points of the convex and concave curves on the rst side, and which are oblique or atan angle to the parallel side faces of said block.

9. A block for a sectional mandrel for use in shaping wrought-metal headers or other tubular articles, the same being of substantially rectangular shape and having one side formed on concave and convex meeting curves, and two straight sides which are parallel to the tangents drawn through the meeting-points from the tube.

11. A mandrelfor use in shaping wroughtmetal headers or other tubular articles, the same comprising a body having a curved or sinuous face, said body being composed of a where the concave curves merge into the convex curves, and a tie-rod passing through said sections for removably securing the same together.

13. A mandrel for use in shaping wroughtmetal headers or other tubular articles, the same comprising a body composed ot' a series of transverse sections provided with alining openings, and a tie-rod passing through said openings for rigidly securing said sections together.

14:. A mandrel for use in shaping wroughtmetal headers or other tubular articles provided with a diaphragm, the same comprising two longitudinal sections each composed of a series of blocks, means for immovably securing said blocks together, and means for uniting said longitudinal sections at their ends.

15. A mandrel for use in shaping wroughtmetal headers or other tubular articles provided With a diaphragm, the same comprising two longitudinal sections provided with transverse corrugations, each section composed of a series of blocks, means for immovably securing said blocks together, and means for uniting said longitudinal sections at their ends.

16. A mandrel for use in shaping wroughtmetal headers or other tubular articles provided with a diaphragm, the same comprising two longitudinal sections, each having a curved or sinuous face and composed of a series of blocks the meeting faces of which are parallel to the tangents to the points where the concave curves merge into the convex curves, means for securing said blocks together, and means for uniting said longitudinal sections at their ends.

17. A mandrel for use in shaping wroughtmetal headers or other tubular articles having a diaphragm, the same comprising two longitudinal sections of serpentine form, said sections being composed of a series of blocks the meeting faces of which are parallel to the tangents to the points Where the concave curves of the body merge into the convex curves, means for im movabl y securing said blocks together, and means for uniting said longitudinal sections at their ends.

In testimony whereof I, the said FRED D. SWEET, have hereunto set my hand.

FRED D. S WEET.

Witnesses:

ROBERT C. TOTTEN, RoBT. D. ToTTEN.

IOU

IOS

Referenced by
Citing PatentFiling datePublication dateApplicantTitle
US2431851 *Sep 11, 1943Dec 2, 1947Boeing Aircraft CoMandrel and method for flattening metal tubes
US4378689 *Jan 2, 1981Apr 5, 1983W. Eckold AgCore for a pipe that is to be bent
US5500995 *Nov 5, 1993Mar 26, 1996Istituto Nazionale Di Fisica NucleareMethod of producing radiofrequency resonating cavities of the weldless type
Classifications
Cooperative ClassificationB21D1/06