DE1627490A1 - Method of making arches - Google Patents

Description

Method for animal production of bows The invention relates to a method for the production of elbows from pipes or hollow bodies by compressing several n ".e: vzLrm-ter cut-offs on the inside of the doge.

-It is ° äekanrit (German patent specification 921.01J), carrot in sections: to be heated in the inside of the doq and by applying force; the-; warmed inside bow section to: -ittzuc £ 1e_n ..- The manufacturer of: bows after deal Verfuhren Requires- demaerkstück correspondingly complex devices for 3r-eu @ -, ung the external application of force: -Ss- iz, -L; It is also customary to align workpieces by creating locally limited arwe.rmunjSchruriipfspanriun =; memory of the jerkstlick. The shrinkage stresses are generated as a result of itaüchuhg by prevented,: j @ rmedehnung and unfinished uuslühlen Lassen-The task of the invention is to develop a process, with which Bö, # .; en kill. desolate. Hollow bodies dimensionally accurate, are made kötüieni; where a äandfüllun @; or Bie-e- Matrices and the tube or riohlkörper become superfluous can be bent without external force: A pipe bend is: manufactured according to the invention so that the pipe in sections on the inside of the pipe bend internal tension forces compressed in axial tiuhtüng where the internal tension forces by "Iärmedehnurit, local- limited places can be generated. First an i "Lohrbögeninneriabschnitt er # .jrärint. Ipatiiiüli @ ä- Forces of the not warmed up ear section are effective Against thermal expansion. The first dive occurs when the -aerstoff of the inner section by 2rw = * noise so pla- has become stic, .that the forces of tension exist, lira to compress it (prevented thermal expansion of the: inlien abscritai-ttes). Then the pipe bend outer section is explained,.: Öhei the "; lerstoff des: pipe bend inner section through; iaxirü. @ el tu; = remains plastic. Due to the S-noise expansion of the internal counterforces are also generated, which the counteract dehnunö. These opposing forces can zjer die Thermal expansion of the outer section- not prevented de- - Inner section is still plastic and this en two-ba.3ii: < is compressed (unhindered., ärmedehnunc, desu @ ertaL. @@. @ _iii t tes). After compressing the inside of the ear curve twice, the Teiiipera-turaüs similar to the section. rierbeig @ ührt, -And the cooling can take place without any appreciable ipai: i.uti @ ..- forces occur. An immersion of the ilbsenrlltte-s in tangential direction does not occur,; feil in this clearing - my prevented stretching occurs, since the cross-section of the ooires orlbody is not rigid, but leathery. ; @: @ durc: r.:, the inasshatige. @ undercut form is guaranteed. The =; oj, elte @tuuchvorgang the _j-onrbo-eninneriseite - ,: ird -üb cl @. @ Itt: this is repeated until the pipe bend is dead: @. L @ a clit e @> ria. rn; iunv has achieved.

For @@. Jz ° i @@ ui`ües -üogeniruzeriabsch £ _ittes und des -oöenau =: enab.chr@it tes - Aze-tj leri-Oxerstoffflarsmen or Tri.dv-iztion; _; rme are suitable, V. ; eil dgmit the places can be locally limited; r @@; e @@@ == rrt. One: even better nb_ `r @ li2; uz. # Her inget @ .rgenössii Dtellen .lr @ ä with üleicllzetiger hi irlu - @ - L of the n = not to be heated ncs cut achieved.

So that the = :, tauehkrwf-Le, which arise from: arm stretching, itself : on the:; warmed over: itt part. evenly. verti - l.eli, become the Aiwärmstellei advantageous in, -rhom: with-similar two-surface shape, their diagonals in tube-axial -1c = ztu, iist, warmed- As a result-: -will the L% aß the "noisy edehlun.- in pipe-axial - 'clearing, distributed over the, iige- ~ = r @ rtezi ürcircumferential part, _ different: - The The difference in:.,. Rmedehiiun size extension is thus approximated in relation p-le.-ch to deinb :: - L @ id from an imaginary central bend, plane, through the jehwerachse des uohres -exordenDie ratio - .; 1 @@% r @ cl @ c: _. @ r-u @@ t- der t @, rrnerdehrlurl: 1Ln also through tiie The steepness of the temperature gradient between the warmed and the unheated part of the ear section can be influenced.

Since some metals and their alloys have very high temperatures for compression must be achieved, is a protection give the atmospheric oxygen through Inert gas is often advantageous.

There are no devices for the production of arches according to the method for the generation of large bending forces still wit shapes (matrices) or sand fillings the inherent disadvantages for the accuracy of the uncut: In the manufacture of braces with short legs, they are otherwise omitted when bending Legs necessary for pipes to transfer the bending force. This allows the Pipe end processing is carried out on four-wire pipes that have not yet been bent, and there is no waste, which is the case with workpieces with large dimensions and costly Materials has a beneficial effect. In order to use the process to protect the @, IJerkstoffes To be carried out under protective gas, the necessary devices are not expensive. After all, the process is not tied to a workshop.

The procedure and its implementation are exemplified on the basis of the drawing explained. -With 1 is a. cylindrical hollow body (e.g. 13. a thick-walled pipe) -described, the one in the direction of arrow-A by compressing the inside of the arch 2 in several inner sections 3-er'Lolgensoll. The diving will take place at different times Place the inside of the arch and repeat it often until the desired Curvature of the arch is achieved.

The double: shrub movement: of the inner section 3 is described, which takes place in section 4 of the hollow body 1. : When heating the inner section -3 this part expands. of the hollow body - due to the peculiarities of the material Thermal expansion in tangential direction can reduce thermal expansion without significant Resistance- take place and are not compressed in this direction.

In the axial direction, the thermal expansion encounters the resistance of the rigid one. not worn 'hollow body section, that of the larger. Rope of the Quersuhnttes is formed, un-ü generated counter-forces. The opposing forces initially only form internal stresses in the hollow body. which act against the direction of the arrow -k. 1. With increasing heating of the inner section 3, the thermal expansion increases, but the tension forces - frame, since the material softens as a result of the further heating. The internal counterforces generated are now sufficient to compress the material of the inner section 3 in the axial direction. The heating of the outer section 5 that now begins has the consequence that this section is axially extended. : a further compression of the inner section 3 in the axial direction caused. It is necessary, however, that the cross-section of the hollow body 1, which lies in the mid-plane between the outer section 5 and the inner section 3, does not assume an excessively high temperature and that: the temperature of the outer section 5, and thus its four-formability, is below the Temperature of the inner section 3 runs.

The localized points 3 and 5 should be approximately diamond-shaped Surface shape 6 and 7 are heated, so that the thermal expansion of the heated areas - CD roughly relates to its: Distance from an imaginary plane through the center of gravity 8 are. This prevents tension forces from being inside the warmed up Places 3 and>, act against each other: For the same reason, the temperature gradient must between the warmed-up places 3 - and 5 - to the unheated part of the section 4 must also be observed.

The next compression of the inside sheet 2 can be in a cold section 4 'of the hollow body.

Claims (5)

p a t`e n t a: n s p r; l c h e 1. rlerzahr en for the production of Bends made of tubes or "cylindrical hollow bodies by upsetting in-axial r-ichtün, - z several heated sections on the arch-tooth side, characterized by that the upsetting forces are external tension forces that are localized by thermal expansion limited places (3, 5) are generated. 2. Implementation of the method next claim. 1, thereby g eker_nzeiehiret, - that first - an inner arch section (3) until the replacement des; Merkstoffes -this sections are warmed up, then a corresponding one 3agenäußenabs.chnitt: (5) - Erwö, rint is and finally the corresponding section (4) cools down. Implementation of the method according to the claims. 1- and Z, thereby marked: that. the double upsetting process according to claim 2 in several sections (4: ') repeated . 4. Implementation of the method-according to claim 2, characterized in that the inner arc sections (3) -bzw. - Doge outcrops (5) by flame or inductor devices known per se. 5. Implementation of the method according to claim 2, characterized in that parts not to be heated of the section. (4) during the warm-up time of the inner arch section (3) and the outer arch section (5) are cooled: 6: - implementation of the method according to claims 4 and 5, - thereby marked, -that the locally limited .--.-places. (3-9--5) roughly rhombic Surface shape (6, -7,) are heated with the -axial direction of the surface diagonal. ?. Implementation of the method according to claims 2 to 5, characterized in that that the sections (4,: 4 ') -during the implementation of the process by an inert gas to be appreciated. -,