US1084881A - Press for making pipes. - Google Patents

Description

' F. GAHLEN. PRESS Fos, MAKlNQ ms. l APPLIATION FILED NOV.6,1912. LSLSB wk @R Panented Jan. 20, 1914 uf Sill "Il 1 the prt-Ss; under the Strain of the work orA "narra" Vr firireia 'FRANZ GAHLELT. OF DUISBURG, GERMANY.

PRESS FOR MAKING PIPES.

Application tiled November 6, 1912.

Specification of Lettera Patent.

Patented Jam 20,1914.

senza No. 729,877.

lio it. known thatl l, ltnxxz (ianLuN, engi* i neer, a Subject ot the llmperur olj (iet-many,

matrix. lNitli auch prennes it was hitherto,

not always poasible to produce pipes with evenly thick wallS; a large portion of the pressed pipes` had to be scrapped, iin-roaming the enst'. of manu'laet'ure. 'l `he rason 'for this trouble lay in the taet', that the mandrel would asaume an eccentric position in the bore oit theI matrix, Such eeeentric position being eanSed by the expansion ot the parteI oit' the intluenee of the heat., by warping ot' the mandrel and like reasons. As the mandrel 'ill maintain the position imparted to it by the presa plunger, as it is cloaely tilted into the Esame, either .fixed or axially displaeeable, il t obvious that the pipe pressed will have a wall o t` uneven thielv'ness.

The present invention relates: to a pren-s, by which the ailorementioned trouble will he avoided. The characteristic `fatture ot' this prees f -onseieta` in the mandrel being arranged So that it can l#wingin the plunger in any direction. ln eonssetpienee ot the mandrel.Q taxing thus able Ato yield in all directions. it will be able to vl'ollow the tendeney of the material to alwaya adjuat the mandrel eoneentrirally. This tendency is a result o'l` the, tolowing; eireumstainea: When the mandrel moves into an eeeentrie position, a higher epetfitie 'loree will be required to it'oree the material through the narrower portion ot the openingl on the one side, than is re quired to l'oree the material through the opposite wider side ot the openingv ln eon setpienee oi'A sueh ('lili'erenee ln the speeilie Atorre required the mandrel will be urged to 'ward the axis oi the matrix until the speeilie `l'oree the Same all around, that until the mandrel is exactly (lo-axial with the matrix.

'My invention further ronaiats in rigidly guidingr the mandrel during the pert'orating ope ation and until its end is properly loated in the die Orasning, and then releasing the mandrel so that itis 'lree to yield, as above deaeribed. By preventing `further axial or longitudinal nnivement, oli the mandrel aliter itsl end has extended into the di'c, a further Yfatture ol advantage is attained in that no considerable length oi the mandrel is retained within the termed' pipe, and there is, upon withdrawal ot the nnt'ndrel, no likelihood of injury to either.

ln the aeeompanyiinr dra wiegeI Figure 1 illustrates a mandrel in an eccentric posar tion with renpeetI to the matrix, due to warping, ete., where the mandrel is rigidly Secured to the plunger an in most known devlees.' Figa. 9. and 3 are longitudil'ial views, partly in section, ot a` prees, in which the ingot is perforated b y the nn'indrel before the pres-Sing operation proper eonnneneed. Fig'. 3tillust Iates in longitudinal section a modified lorm ot' the invention.

l'n sueh drawings, n. is the mandrel, b iS the matrix, (l iS the ram` with an exchangeable preise plate all, c in the reeeivin" and is the ingrot; g in a eronahead which can be longitmlinally moved toward the press plunger l1, an l in which the mandrel fr is Secured at its rear end.

The operation ol sueh a prees is aa follows: After the ina-ot has been introduced into the, reeeiver, the ram n'. is advanced together with the mandrel until the perforatf iner of the ingrat; is eompleted and the prees pla te rl" almost. `tran-liesl the ingrot. This inoment is rhown in Fig. Q. During auch per- `foratien the pressure ot the auxiliary cylinder 'i provided in the plunger z, arts'onthe cronishead .f/ and thereby on the mandrel (i. The latter is: eentered in a short guide la at the trout end ot the ram il. 'l'llilgiiitie is ot a little larger diameter than the' front end ot the mandrel determining' the Size of the pipe to be pressed. ope ation is eommenetal. the erosshead g iS seeured in known manner b v .means oi" tlie rods Z, so that the mandrel will not partielpate in the it'urther travel of the ram (I. The ram d will no\v ad vanre. alone, telescope over the mandrel and the guide will leave the tliii'ker part, o'l the mandrel. S'o that during the following pressing operation it can Ylollow tbel atm-ementioned tendency of the material to more the mandrel tann'entrieally to the matrix. ln order that the mandrel letore the presing i side of the press disk d1.

should oppose this tendency as little as pos` sible, it is secured at its rear end in the crosshead g s0 that it can oscillate therein.

Fig. 3 shows'the press at a given moment during the pressing operation.

At the front end of the ram- (Z, between the ram. and .the press disk Z1 a ring m may be provided, Which is radially movable with the mandrel, .and will prevent the material from entering between the ram and. the mandrel.l In place ofr such ring,'a ring n` may be provided for the same purpose, outy Fig. 4, the mandrel will participate in the Whole travel of the ram d. In this case .the crosshead g and then auxiliary cylinder z' are dispensable. The mandrel is secured to the ram only,in`such a manner, that it Will be held -coaxially to the ram during the perforating operati-on,

In the form shown i and, ean"'oscillate during the pressing operation?.l ,At-its rear end the mandrel is cen- ,c .tere "in the ram, and at its front end in a short guide la, the sami as 4shown in l Figs. 2 and 3.0 During the perforatingope'ration the mandrel'will be held in its position by until its end extends into the die-opening,

means fcrvpreventing further forward longitudinal movement ofthe mandrel, means for rigidly guiding said mandrel during' the perforating movement and subsequently releasing it, means for' forcing the metal through the die and around the mandrel,

and means permitting the mandrel -to automatically center itself in the die.

2. .A press for producing tubes, comprising a metal receptacle, a die, a self-centering mandrel, means for lforcing said mandrel through said receptacle to perforate the metal and until its end extends'into the die-opening, means for rigidly guiding said mandrel during the perforating movement and subsequently releasing it, and means for forcing the metal through the die and around the released self-centering mandrel.

3. A press for producing tubes, comprising a metal receptacle, a die, an oscillatable mandrel, a crosshcad to which said mandrel. is connected by a universal joint, means for forcing and for guiding said mandrel through the said receptacle until -its end extends into the die-opening] means for preventing further forward longitudinal movement of the mandrel, means for freeing the mandrel from said guiding-means, thereby permitting the mandrel to oscillate, and

means for forcing the -metal through the die` vmeans for further moving said plunger to force the metal through the die.

5. A press for producing tubes, comprisin a metal receptacle, an annular die, a ho low plunger, a crosshead having a mandrel connected thereto by a universal joint, said mandrel extending throughthe opening in the plunger, the Wal-l of said openingbeing contracted at its lower end to form a guiding-surface for an enlarged portion of said plunger, means for moving said plunger and mandrel together until theend of the mandrel has entered the die-opening, means ,for preventing further movement of the mandrel, and means for further moving said plunger to force the metal through the die and around the mandrel.

6. A press for producing tubes, comprising a metal receptacle having an annular die, a self-centering mandrel, means for moving said mandrel through the receptacle to perforate the metal and enter the die, a plunger 'surrounding said mandrel adapted to-press the metal through said die,

said mandrel projecting loosely through the end of the plunger, and a slidable .metalretaining ring on the face of said plunger and around said mandrel.

7. A press for producing-tubes, comprising a metal-receptacle having an annular die, an' oscillatable mandrel,means for moving said mandrel through said receptacle to perforate the metal, a plunger surrounding said mandrel adapted to press the metal through said die when the forward end of the` mandrelfhas reached said die, means for rigidlyy maintaining said mandrel centrallyof said receptacle during the perforating step, means for releasing said mandrel to permit it-'to oscillate Whe-n said plunger is operated, and a metal-retaining ring iitting around said mandrel and slidably en-.

gaging the face of said plunger.

8. A press for producing tubes, compris- .ing the, perforating step and subsetnently to releasq said mandrel from its rigi position, Saul mandrel projecting loosely throughthe end of saidplungeiyand free tn nscillzxte thm-vin during tln-` inizwinxf :Li'ter Y its release from wniil rigid punition.

ln testimony wlmi-col I ullix my Awignntlnu in ,plcsenccnt' two witnesses.

l FRANZ (lillllllilN. Witnesses:

lli-:LEN Nwnn, ALBERT NUFER.

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