US2278293A

US2278293A - Forging apparatus

Info

Publication number: US2278293A
Application number: US388841A
Authority: US
Inventors: William J Watson
Original assignee: Individual
Current assignee: Individual
Priority date: 1941-04-16
Filing date: 1941-04-16
Publication date: 1942-03-31
Anticipated expiration: 1959-03-31

Description

March 31, 1942. w J w s 2,278,293

FORGING APPARATUS Filed April 16, 1941 2 Sheets-Sheet l ATTORNEYS March 31, 1942. w, J w so' 2,278,293

FORGING APPARATUS Filed April 16, 1941 2 Sheets-Sheet 2 'INVENTOR ATTORNEY S Patented Mar. 31, 1942 UNITED STATEfi PATENT OFFICE FORGING APPARATUS William J. Watson, Dunkirk, N. Y.

Application April 16, 1941, Serial No. 388,841

2 Claims.

made from a metal billet of square cross section by repeatedly heating the same and subjecting it to the swaging operation of co-operating dies until a blank was produced having an enlarged central part and two reduced stems projecting lengthwise from opposite sides of this enlargement. Thereafter this enlargement was severed crosswise midway of its length and thereby forming two mandrels each of which consisted of an enlarged head having a flat top and a reduced stem projecting from the underside of the head.

This method of manufacturing these mandrels is slow and expensive and as a considerable number are used for expanding pipes the cost of doing this work is unduly high.

It is the object of this invention to provide a forging apparatus whereby these mandrels can be made quickly and easily at low cost, which apparatus is of simple and durable construction and easily operable without requiring great skill.

In the accompanying drawings:

Fig. l is a perspective view of a mandrel made by the use of the forging apparatus embodying this invention.

Fig. 2 is a similar view of a blank which has been prepared from a billet and to be completed into a mandrel by the use of the present forging apparatus.

Fig. 3 is a vertical longitudinal section of one form of this invention showing the parts in the position which they occupy after the operation of forging a head on the stem of a mandrel has been completed.

Figs. 4 and 5 are horizontal sections taken on the correspondingly numbered lines in Fig. 2.

Fig. 6 is a section similar to Fig. 1, but showing the spacing member omitted and the parts in the position which they occupy after the die sections have been released from the completed mandrel.

Fig. 7 is an exploded view showing the finished mandrel in elevation and the several die sections in vertical sections and spaced from the mandrel and from each other.

Fig. 8 is a perspective view of one of the die sections which receives the stem of the mandrel.

Fig. 9 is a vertical section similar to Fig. 3 but showing a one piece die for forming the head on the stem of the mandrel.

Fig. 10 is a top plan view of the apparatus shown in Fig. 9. I

Fig. 11 is a perspective view of a one piece head forming die made with vertical sides instead of inclined sides, as shown in Fig. 9.

In the following description similar reference characters indicate like parts .in the; several figures of the drawings.

The blanks or work pieces which are operated on by the present forging apparatus for converting the same into tube or pipe expanding mandrels may be prepared in any suitable manner but I preferably by hammering a metal billet so that it is round in cross section and of uniform diameter throughout its length, as shown at 20 in Fig. 2, and provided with flattransverse faces 2 l, 22 at its opposite ends, as shown in the same figure.

After being operated upon by the present forging apparatus this blank is converted into a mandrel which is somewhat shorter than the blank and forms a relatively reduced stem or body 23 which is of the same diameter throughout its length and provided with a flat transverse face 24 at its lower end, and an enlarged head 25 at the upper end of the stem, which head preferably has a flat transverse top face 26, a narrow cylindrical face 21 on the rim or upper part of its periphery, and a comparatively long downwardly tapering face 23 on the lower part of its periphery.

The forging apparatus whereby blanks of the character shown in Fig. 2 are converted into mandrels of theshape shown in Fig. 1, and which embodies the present invention is constructed as follows:

Referring to Figs. 1-8, the numeral 29 represents an anvil, or other support for the lower end of the blank and the underside of the forging apparatus and 30 a hammer which is adapted to engage with the upper end of the blank and possibly with an adjacent upper part of the forging apparatus during the operation of converting a blank into a mandrel. If desired this anvil and hammer may constitute the bed and ram of a hydraulic or other press.

The numeral 3| represents two gripping or clamping die sections or jaws arranged on opposite sides of the vertical axis of the forging apparatus and which are provided respectively on their inner opposing sides with semi-cylindrical grooves 32 extending vertically the full height of these die sections and adapted to engage with opposite sides of the periphery of the intermediate part of the blank and leaving the lower and upper end portions exposed below and above the clamping die sections.

011 the outer sides of the clamping die sections opposite the grooves 32 the same are provided respectively with wedging faces 32 which are inclined so that the wedging faces of the two clamping die sections 3| converge downwardly. The lateral sides 34 of the clamping die sections are preferably similarly inclined.

The numeral 35 represents a holder or frame which preferably has the form of an upright tube which is rectangular in horizontal section and adapted to receive within the lower part of its vertical opening the two clamping die sections or jaws 3|. The inner faces or walls 36 of the holder opposite the inclined outer sides 33 of the clamping die section 3| are correspondingly inclined and engage therewith, as shown in Fig. 3, and the walls or faces 37 of the holder 35 are inclined the same as the lateral sides 34 of the clamping die sections 3| and engage therewith.

During the operation of forging a blank from the shape, shown in Fig. 2, into the shape of a mandrel shown in Fig. 1, the holder is supported at a distance from the anvil 29 by. interposing a spacer 38, preferably having the form of a rectangular frame, between the top of the anvil and the underside of the holder, and thereby permit the lower ends of the clamping die sections to project below the lower end of the holder, as shown in Fig. 3, during the forging operation.

The numeral 39 represents two sections of a forming die which receives the upper part of the blank and is provided with a cavity or face into which the adjacent part of the blank is driven by the hammer so as to upset this part of the blank length and produce an enlargement thereon which forms the head of the mandrel. The forming die sections engage each other on a diametrical line passing through the longitudinal axis of the same and their opposing inner sides are provided with die faces consisting of two lower recesses 4!! which together produce a small throat forming die face which has a diameter corresponding to the diameter of the combined grooves 32 in the clamping die sections 3|, two intermediate recesses 4| flaring upwardly from the lower recesses 46 and together producing a conical head forming die cavity, and two upper recesses 42 arranged at the upper end of the flaring intermediate recesses 4| and together forming a cylindrical rim die face which corresponds in diameter to the diameter of the upper end of the conical body die cavity. This sectional forming die rests on the upper end of the lower clamping die sections 3| which project with their lower parts into the upper part of the tubular holder during operation of forging a head on a blank to produce a mandrel. Spreading of the head forming die sections 39 is prevented during the forging operation by a retaining frame 43 which is preferably of rectangular form and surrounds the upper part of the head forming die sections, and rests on the upper end of the main tubular holder 35. The outer sides 44 of the head forming die sections opposite the inner forming faces thereof are inclined and converge downwardly and engage with the correspondingly inclined adjacent inner sides 45 of the retaining frame 43 and the inclined inner sides 36 of the tubular holder 35, as shown in Fig. 3, and theopposite lateral sides 43 of the head forming die sections are also preferably inclined and engage with the opposing inner sides 47 of the retaining frame.

For the purpose of holding the sections 33 .of the clamping die against lengthwise displacement one relative to another transverse dowels 49 are employed which are seated at their opposite ends in the openings in the opposing sides of these die sections, and for the same reason transverse dowels 50 are seated at their opposite ends in openings in the opposing sides of the head forming die sections 39.

For convenience in transporting the tubular holder and the parts mounted thereon the same is provided on its opposite sides with perforated brackets 48 adapted to receive a transporting fork or the like.

In the operation of forging a mandrel by this apparatus the several members are first loosely assembled in substantially the position shown in Fig. 3 with a blank of the character shown in Fig. 2 placed vertically in openings formed between the clamping die sections 3| and the forming die sections 39 with the lower end of the blank resting on the anvil and the upper end of the same projecting above the head forming die sections. ward blows or strokes are delivered by the hammer or ram 30 against the upper end of the blank so that the latter is upset or mushroomed sufiiciently to fill the die cavity between the die sections 39 and form the enlarged head 25 on the upper end of the stem 23 which latter is held upright between the clamping die sections and the lower parts of the forming die sections and prevented from moving downwardly by the anvil 29, as shown in Fig. 3.

While the head is being formed on the upper end of the blank a downward pressure is exerted against the forming die sections which causes the same to bind in the retaining frame 43 and the holder 35 and a downward pressure is also exerted against the clamping die sections 3| which 7 die sections are released from the holder and retaining frame a suflicient extent to release the completed mandrel, as shown in Fig. 6. The downward pressure may be applied to the retaining frame and holder by any suitable means, for example by a vertically movable hollow ram or hammer 5|, as shown in Fig. 6.

During the operation of forging'the head on the stem of the mandrel the die sections are held rigidly in their operative position by the holder and retaining frame and thus insure perfectly formed mandrels.

By making the forming die sections separate from the clamping die sections the cost of the apparatus may be materially reduced and still maintain its durability inasmuch as this permits the forming die sections which are subject to severe usage to be made of durable high cost steel while the clamping die sections which are not subject to great wear may be made of metal which is strong but less costly.

While in this position one or more doWn' If desired the head forming die may be made in one piece, as shown at 52 in Figs. 9, l0 and 11 in which construction however the head forming die is liable to stick on the stem of the finished mandrel and necessitate one or more blows for driving the same out of the one piece head forming die. Otherwise the construction shown in Figs. 9, 10 and 11 is like that shown in Figs. 3-8 and is operated in the same manner for producing mandrels of the character described.

I claim as my invention:

1. An apparatus for forging mandrels having a slender stem and an enlarged head at the upper end of the stem from a blank which is of uniform shape throughout its length, said apparatus comprising a lower pair of opposed clamping die sections provided on their inner sides with faces adapted to grip the lower part of the blank, an upper pair of opposed forming die sections provided on their inner sides with faces adapted to form the head on the blank, a lower holder enclosing said clamping die sections and having wedging engagement with the outer sides of the clamping die sections, an upper retainer enclosing said forming die sections and having wedging engagement with the outer sides thereof and a spacer adapted to be interposed between the.

underside of the holder and an anvil for supporting the holder at a distance from the anvil and permitting the lower die sections to project below the holder while the blank is arranged between the upper and lower pair of die sections and the lower end of the blank is resting on the anvil while theupper end ofthe same is engaged by a hammer for producing a head thereon.

2. An apparatus for forging mandrels having a slender stem and an enlarged head at the upper end of the stem from a blank which is of uniform shape throughout its length, said apparatus comprising a lower pair of opposed clamping die sections provided on their inner sides with faces adapted to grip the lower part of the blank, an upper die provided on its inner side with a face adapted to form the head on the blank, a lower holder enclosing said clamping die sections and having wedging engagement with the outer sides of the clamping die sections, an upper retainer enclosing said forming die and having wedging engagement with the outer side thereof, a spacer adapted to be interposed between the underside of the holder and an anvil for supporting the holder at a distance from the anvil and permitting the lower die sections to project below the holder while the blank is arranged between the upper die and the lower pair of die sections and the lower end of the blank is resting on the anvil while the upper end of the same is engaged by a hammer for producing a head thereon,

WILLIAM J. WATSON.