DE2031897A1 - Furnace arrangement - Google Patents

Description

Furnace arrangement

The invention relates to a furnace arrangement below Beb tsgas taking place sintering in sintering boxes. . "all objects, each with a passage jranal for the sintering boxes having a wax expulsion furnace and sintering furnace, which are gas-tight to the outside by means of a YerMndungskanal are connected in series, and further jorting means for conveying the sintered boxes through their channel.

In the production of sintered objects from powdery It is customary to add additives to the powder to facilitate the pressing process, in the material general wax, preferably paraffin, to be added Sintering are driven out of the compact again, otherwise the quality of the sintered object will suffer The expulsion of the wax in the sintering furnace also had adverse effects on the cooking of the sintering boxes in the oven and the heater. Therefore, so-called wax expelling ovens are connected upstream of the sintering oven, in which at suitable temperatures it is generally 300 - 500 ° C amount, the wax is expelled prior to sintering. For the purposes of the present invention, the term “wax stripping oven” here meant o'er furnace, the expulsion Additives from the compact to be sintered to facilitate pressing are used, regardless of whether they are wax or other additives that facilitate pressing

Sintering in the sintering furnace takes place at very high temperatures; which are below the melting point of the powder in question; in the case of iron powder, for example, at approx. _c H5Ö

109883/0774 0AD ORIGINAL

135ο ⁰ O, Lie Sinter boxes are usually made of pure iron · They lose a lot of strength at the high oil temperatures in the sintering furnace, so that they are only pushed through the sintering furnace with relatively low pushing forces to avoid excessive deformation may · In order to reduce these pushing forces to acceptable values, is

it is known to arrange the sintering furnace at an angle, the Sinter boxes through its through-channel at an angle from ~ been pushed through in the leading direction. That Sintering in the sintering furnace takes place to avoid oxidation under protective gas, for example hydrogen, or in a vacuum. The sintering in a vacuum, however, makes complicated and expensive apparatus necessary to operate, so that if possible sinters in a protective gas atmosphere

If the wax expelling furnace is not connected in series with the sintering furnace, the sintering boxes must be cooled after the wax expelling in a protective gas atmosphere before they are removed from the furnace in order to avoid oxidation of the sintered material. In order to avoid the heat losses caused by this cooling and also for reasons of efficient production, it is known to use the wax. Stripping furnace and the sintering furnace by means of a gas-tight connection channel to the outside. To be connected in series · The protective gas then flows through the sintering furnace in countercurrent in the conveying direction of the sintering boxes, then the connection channel and then the Wachsaus ™. kiln. As to work for economic and technical reasons, with low flow rates possible of the protective gas must ₉ bereitet'es here

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Difficulties »to prevent the in the wax stripping oven Wax vapor that has got into the protective gas does not flow into the sintering furnace as quickly as possible, unless it is protective gas is also passed into the transition zone one, which is uneconomical, or one makes the transition gone very long. If you have the two ovens arranged horizontally one behind the other and designed as simple push-through ovens, then must in the latter case the total length of the furnace assembly including the Connection channel are taken for a very long time. In the case of push-through ovens, the resistance to movement then increases of the sinter boxes unsustainable. In order to keep this resistance to movement within limits, it is known to use sinter boxes to be lifted cyclically using the walking beam and moving forward by one step on the walking beam to move and then to put it down again. These walking beam ovens However, they are expensive and have a relatively large consumption of energy and protective gas, with the When the walking beam is moved, the protective gas flows are also technically unfavorable in the sintering furnace can affect. Therefore, those already mentioned, which are inclined to the horizontal, are more favorable Sintering furnace. If you do this (but the wax from r If the driving furnace is arranged on the same axis as the sintering furnace, the risk of the wax vapor penetrating into the sintering furnace is particularly large. There is also the risk that the protective gas will be released when the wax stripping furnace is being charged with sinter boxes from the loading opening to the outside can escape, which can lead to deflagrations or even explosions. To eliminate the latter disadvantage.

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It is known »to arrange such a furnace arrangement as a whole tiltable in order to be able to bring this furnace arrangement into a horizontal position during loading and unloading. Such an arrangement is only conceivable in relatively small systems · In addition, the wax can still get into the sintering furnace where ea? has a sooting and carburizing effect on the material to be sintered and the heating device "

Another difficulty is that the goods in the sintering boxes are in general must not be exposed to vibrations, as otherwise it would lead to the welding of adjacent ones in the sintering furnace Siriter items may come o

It is therefore an object of the invention to create a furnace arrangement of the type mentioned at the outset in which the aforementioned fencing parts of the known furnace arrangement are avoided in a structurally simple and operationally reliable manner and which, in particular, manages with particularly low operating costs Sintering in the sintering furnace enables »a low consumption of protective gas & at which, furthermore, the sintered material in the sintering boxes is not exposed to any vibrations or changes in position» which can lead to welding in the sintering furnace, in which furthermore the vapors produced in the Wöehsaustreibofen due to the expulsion of the wax are not in can reach the sintering furnace, and which also has other advantages

To solve this problem, the invention provides for a furnace arrangement of the type mentioned at the outset,

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that the passage channel of the wax expelling furnace in the conveying direction of the sintering boxes diagonally upwards and the passage channel of the sintering furnace in the conveying direction of the sintering boxes is directed obliquely downwards in a manner known per se, and that

the canal system is one of the sloping upwards Conveying direction in the obliquely downward conveying direction leading channel curvature that of the Sinter boxes without tipping over in an inclined position opposite to that assumed during the upward movement Sloping position is traversed. .

With this arrangement, the two ovens can be as simple Push-through ovens which communicate with one another via the connecting channel without the There is a risk that the wax vapor produced in the wax stripping oven will enter the. Sintering furnace can get, since he is with the commonly used Scftutzeaeen heavier than that Protective gas is and so strives to sink down and therefore also with very low flow velocities of the protective gas due to the inclined upward direction in the conveying direction The passage channel tends to move in the direction of the flow of the protective gas, i.e. in the direction of the entrance of the Drive out wax fens to flow and in this way completely with the protective gas, which is preferably hydrogen gas can be, is carried away »The connecting channel can are kept very short, which means that the furnace arrangement, even with a large capacity, a small overall size may have·

It is particularly favorable if the

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Is U-shaped.

Due to the short length of the connecting channel that can be achieved the heat losses are also reduced.

The curvature of the channel also reduces the pushing forces required on the sinter boxes for pushing them through the furnaces} since the sinter boxes are arranged in several straight lines angled into one another ₉ whereby Jefie can "be moved" by a pushing device.

In the case of the furnace arrangement according to the invention, it can therefore be provided with particular advantage that the channel system has slideways. sui which the sintering cases by means of thrusters _s are slidable so that no moving! conveyor belts required

Preferably vorg @ s © feea ₃ is that the line passing through the duct system Förderwegs- © xitlang the sintering boxes waadeÄü in Bodenhoh® the sintering boxes is flat, "you will Siaterkistea. <ä © as ₉ although through the wax = - egg stripper obliquely upwards Mndnrch nnü. anirch den-Sinterofen "diagonally © partly because of this are promoted cliiscii di © KanalkruaaiBsssig ^ iadisrch

so from the oblique

atifwäzrba fattening ducks in fii © selrlg © "forward leading Hiehteng i & @ 2? fitet, · that they do not change ite? e Bctelglage, so that they keiaea jerky · Q®f @ lg @ ad @ n Sipp" w © gungen soaetigea Ersehfittss'isagea ami itoea ISrderweg aus · = "setat are _f by ti © 41 © Gafate .von Besehädigungea der

Objects located in the sintering boxes or the Risk of welding of neighboring objects in the sintering furnace could be caused »Preferred ίεφ here provided that the conveying means are designed so that they pass the sintering boxes through the channel system under B&B old their spatial longitudinal orientation demand rotation-free · The sinter boxes then keep the same inclined position free of vibrations during their entire conveying path through the channel system at without being rotated * It goes without saying that this although it is particularly advantageous that the invention also applies to designs of this channel system and types the promotion of the sinter boxes extends, which do not fully correspond to this ideal case, since they are still opposite the furnace arrangements according to the state of the art (technology considerable Advantages in terms of the protective gas guidance, the dissipation of the wax mist, the simple, operationally reliable Type of construction, the transport of the sintered boxes and other properties offers, if within certain limits, changes in the inclination or rotations or swiveling of the sintering boxes are permitted, provided they do not lead to such vibrations or changes in position by the objects lying next to each other are welded together in the sintering furnace «.

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Due to the fact that there is no risk of wax vapor binding into the branch of the duct containing the sintering furnace, the clear cross-sections of the connecting channel can also be made so large that the Sinter boxes with the inevitable thermal and mechanical deformations, even among the most unfavorable Under certain circumstances, there is no tendency to jam on the walls of the connecting duct

The consumption of protective gas is also significantly reduced · It was shown that, for example, with a Inert gas consumption of the order of magnitude of 100 l / h with a furnace arrangement according to the invention is average Big comes by

You diagonally upward arrangement of the den Wachustreibofen having channel branch also has the important advantage that the protective gas due to its thermal or other buoyancy does not endeavor from the one located at the lower end of this branch of the canal To escape opening when this is temporarily opened to insert a sinter box. This is important for the explosion safety of the furnace arrangement and reduced also the need for protective gas.

In order to prevent penetration of the wax vapor through the protective gas easier and better than before, can according to the invention in a furnace arrangement of the type mentioned at the outset also be provided that between the in a known manner in the conveying direction of the sinter boxes obliquely downwards directed, the sintering furnace having canal branch and the canal branch of the wax stripping furnace Channel system, a channel bend is interposed, which is one of the channel branch having the wax expulsion furnace angled branching canal -

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branch having its longitudinal axis at least approximately located in a vertical plane · ·

In this design of the channel system it can be provided in some cases that the sintering furnace The branch of the channel is directed obliquely downwards or horizontally in the conveying direction of the sintering boxes

in particular the furnace arrangement according to the invention is for dxe use

created by protective gases, the specific weight of which is smaller than the specific gravity of the wax vapors produced in the wax stripping oven. However, it is conceivable that the invention Furnace arrangement, if necessary with suitable modification of those preventing the passage of wax vapors Channel curvature can also be used for protective gases whose specific weight is greater than the specific weight of the wax vapors is.

Further features of the invention are in the following Description, the subclaims and the drawing described or shown, it being understood that the invention can be realized in numerous other embodiments

Show in the drawing

1 shows a first example of an embodiment according to the invention Furnace arrangement in a schematic diagram, all for understanding parts not important to the invention are omitted,

FIG. 2 shows a variant of the furnace arrangement according to FIG. 1 in likewise schematic, graphical view,

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lig · 5 to 5 diagrams of the conveying routes of others furnace arrangements according to the invention

The furnace arrangement shown in Fig. 1 is on a horizontal floor 10, whereby to illustrate the inclination of this furnace arrangement height-adjustable © support feet 11 are drawn, but in their Stell® in reality of course, one that supports the furnace arrangement over its entire length and is preferably adjustable in its inclination Frame steps · ·

This furnace arrangement has a wax expelling furnace 12 and a sintering furnace 13, which can be of the usual type and whose passageways are inclined at equal angles of preferably 15 ° to the horizontal and are arranged parallel to one another. A coaxial feed channel 14 is connected upstream of the wax expulsion furnace 12, the inlet opening of which can be closed in a gas-tight manner by a SJir 15, whereby a piston rod © of a Koltoea cylinder unit 16 forming a pusher is guided in an opening of the door and can be pushed into the inside of the channel, in the straight, ascending channel branch 1? located borrow from rechteckfSrmigen sintering boxes 19 from! Bisen after introduction of a new sinter box around the Läng® a sinter box to move upwards "ZNR ■ simplify the presentation are just a few Sint © rkä represented most of simultaneously present in the Kanelsyetem * In with rising channel branch 17 and the descending branch 18 is j® © iae Eeihe.von with iiiren eetaalea

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Front sides of adjoining sinter boxes Xn the horizontal channel branch 20 can be a row of sinter boxes adjoining one another on their long sides, or it can also be used to only push the sinter boxes through in a single pushing process from the point of curvature 33 to the point of curvature y \ - . In some cases, the channel branch 20 can advantageously also be so wide that two or more sintering boxes, which are in contact with one another with their narrow end faces, are pushed through it at the same time can·

In a side wall of the feed channel is in the Near its inlet opening a drill 21 arranged for the discharge of protective gas, which when the stay Sinter boxes in the wax expulsion furnace at temperatures of 300 - 500 ° C from the objects in them expelled wax vapor Depending on the temperature as a gas or Aerosol. As a result of the inclined arrangement of the channel branch 1? this wax vapor flows, the heavier than the protective gas, in the protective gas in its flow direction, which here leads obliquely downwards, from the Wax removal oven 12. ί

The exit of the wax expelling furnace 12 is gas-tight to the outside of the sintering furnace 13 via a Connecting channel 22 communicatingly connected, which has a U-shaped channel curvature, this channel curvature

12 -

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two branch 20 connected by the straight channel has right-angled, sharp-edged Krünnaungsstellen 33 and 34. The two longitudinal legs of the connecting channel 22 forming channel areas 24 and 25 are on the same axis with the ovens 12 adjacent to them, The bottom of the channel branch 20 is level with the floors of the two channel branches 17 and 18 · The height and width the clear cross-sections of the channel areas 24 and 25 are somewhat .... ^., ■ * ■,., Greater than the height and Width of the front side of the individual sinter box 19 · The height and width of the clear cross-section of the channel area On the other hand, 20 is something. greater than the length and height of the long side walls of the individual sinter box.

The outlet of the sintering furnace 13 is followed by a discharge channel 26, which has a water-cooled area 27, so that the sinter boxes coming out of the sintering furnace at extremely high temperatures are cooled down to almost room temperature before they leave the discharge channel, so that when the sinter boxes are removed from the through a door closable outlet opening of the discharge channel 26 to prevent oxidation of the sintered objects.

In the one. Side wall of the discharge channel 26 in, the A supply pipe 30 for protective gas is arranged near its outlet opening. In a known manner, further Supply lines for protective gas may be provided which, if necessary, are temporarily charged with protective gas only when a sinter box is removed

09883/01? k BAD ORIGINAL

c-13

The penetration of air into the discharge duct 26 is even better prevented. The discharge channel 26 is coaxial with the sintering furnace 13. The outlet and the input of the supply and discharge channel for the sinter boxes are arranged in this invention according to the invention at a relatively small distance from each other at the same height, whereby the loading with sinter boxes and the removal of the sinter boxes through the operator is facilitated. Also this furnace arrangement has required addition to their other advantages © inen minimal space ^.

This furnace arrangement is preferred for sintering made of metallic powder with the addition of wax (paraffin) pressed standard parts provided, but can they are also advantageous for other sintered objects, for example for sintered objects made of ceramic powder » be used.

To move the sintered compacts & sten through the channel system through a total of three formed as a cylinder-piston units thrusters 16 j 51 m £ 5, VO # ge ~ see their piston rods through stuffing boxes or * · through same into the interior of the channel system for incrementally moving the sinter boxes intervene »Bfce free ends of the piston rods can be provided with widened heads»

It goes without saying that instead of the cylinder Solbeu units shown euoh other Fördenattal je naoli Srf orderais can be provided, bepw, drivable Zahasbangan, manually operable push eyes, or dergleiohan.

109883/0774 BATH _{0R | QINA1} ;

The removal of the individual sintering boxes 19 from the outlet of the discharge channel 26 can be expedient done manually. When a sinter "

box has been removed, the thrust device 32 can then be operated hydraulically or pneumatically are, as a result of such actuation by advancing their piston rod an im Area of the corner 34 of the connecting channel 22 is located Sinter box by one., Corresponding to its length

into the channel branch 18 /, which then moves the other sintering boxes in this channel branch with it.After the piston rod has been moved back, a new sintering box can be moved into the vacated gap at position © 34 by means of the pusher device 31, the piston rod of which follows - their "actuation of the sintering box located at the point of curvature 53 of the connecting channel, 2 ~ 2 - in a work cycle or ~

with in ü & m Kanalsswäig "'

'- daÖ in the IMemjagsstelle gelaagf / aa der KrümmTOgsstelle Sinterfttest' according to the piston rod of the & Aiisgaagslage can the. die 'iea wrangeiiend- ia

eia aeue ^ sinter box eiae the ßi? öBe one

"to be operated" - '

14 by hand "

-dbende distance '

"here the gesaurfee 'Beihe' te? in." tea channel ^ weig '-. I ψ- -

in the

10 9883/077

_{0RjG! NAL 1NS} pbcted

This conveying process, carried out in several work steps then repeats itself from time to time, the length of time between two such shifting sequences as is taken that the dwell times of the sintering boxes required for sintering and expelling wax in the Ovens can be achieved

The connecting channel 22 is thermally insulated so that the lowest possible heat losses occur *

During operation, protective gas is continuously passed through the feed pipe 30 into the. Diverting channel 26 introduced and flows slowly in countercurrent to the conveying direction the sinter boxes 19 through the discharge channel 26, the sintering furnace 13 ", the connecting channel 22, the wax expelling furnace 12 and the supply channel 14 and leaves this channel system through the discharge pipe 21

The output can hit the furnace arrangement shown of the discharge channel 26. and the inlet of the feed channel for taking out or loading the sintering boxes open without the risk of larger shielding gas clouds escaping and air entering. Even it is completely ruled out that wax » steam can pass through the connecting channel 22 into the sintering furnace.

The entire conveying route of the Sinterkästea. 19 until the output of the JLbleit = "channel from the entrance of Zufahrungskanales 14 26 extends in a plane © _$ se that the Siaterkästen

f öggea / ö ?? *.

BATH ORIGINAL

after inserting it into the feed channel · » the inclined position taken unchanged on its entire way through the canal system and as a result of the shifting processes described, too are not rotated and are not exposed to vibrations or jerky movements «That Sintered material can therefore not shift, so that there is a risk of welding of neighboring sintered objects is avoided in the sintering furnace.

All these advantages are structurally particularly simple and operationally reliable with little space requirement the furnace arrangement and low inert gas and energy consumption.

In the furnace assembly of Figure 2, all of the parts are the parts of the pig. 1 correspond with the same reference numerals provided, which are provided with a prime to distinguish them from the reference numerals of FIG. 1.

This furnace arrangement according to FIG. 2 differs of the furnace arrangement according to FIG. 1 essentially in that the axial directions of the through channels of the Sintering furnace 13 * and the wax stripping furnace 12 'at right angles arranged to each other and correspondingly the connection channel 22 * is formed at right angles. The as Support for the sintering boxes serving bottom of the entrance of the feed channel 14 'to the exit of the Ableitkanales 26 'leading, right-angled channel system is also flat, so that the means of the two as

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, Cylinder-piston units designed thrust devices 16 'and 32' can be pushed through step by step Sinter boxes do not change their inclination and are not rotated. This is achieved by that the right-angled point of curvature 34 · 'des Connection channel 22 'with respect to the openings of the discharge and the drainage channel located at the level of the base 10' Feed channel is higher, which is indicated in the drawing by drawing a vertical support 11 '» In reality, instead of this support, the furnace arrangement is of course in the appropriate position holding frame provided.

This furnace arrangement has compared to the arrangement according to Pig. 1 the disadvantage of a somewhat larger space requirement and also the disadvantage that the sinter boxes constantly on one side of the receiving and leading canal issue. Otherwise, the advantages are practically the same as in the Pig arrangement. 1 scored.

The width and height of the channel cross-sections of the ascending and descending channel branches 17 'and 18' are of the same size in this exemplary embodiment, which makes the use of square sintered boxes necessary. If, on the other hand, rectangular sintering boxes, for example as in Fig. 1, are to be used, then either the clear cross-section of the ascending or descending canal branch must have a clear width that is slightly greater than the length of the sintering boxes for the rotation-free conveyance of the sintering boxes , because these sinter boxes are then in one of these

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Channel branches displaced transversely to their longitudinal direction by the associated poking device 16 or 52 ' whereas they are shifted lengthways in the other branch of the canal «

The operation of this arrangement corresponds to the furnace according to Fig. 1, with the difference that only two thrusters for alternately, gradual displacement of the W-sensitive Sinterkastenrsihen in the channel branches 17 'and 18' loading are required.

As can be seen from Fig. 2, you can make the inclinations of the longitudinal axes of the ascending channel branch 17 'and of the descending channel branch 18' to the horizontal plane of different sizes in this embodiment while maintaining the flat conveying path by moving them around the longitudinal axis -the other channel branch swiveled up or down * If necessary, adjusting means for adjusting the inclination of at least one channel branch can be provided in order to be able _{to adjust them to particularly favorable values from case to case c}

'Wenn'der Kanalsswaig 17 ^δ nearly or full tBodlg is placed horizontally, Waefcsianspf came in $ @ n sintering furnace get "what is very disadvantageous * If ®S jecloch. With the use of higher flow rates a @ e Sohutagases or introducing bus at al lohen Ootatssgaees in the terbination channel 22 »succeeds, as a result, the canal branch 17 ^{9 can} also be placed horizontally, with the further advantage the flat Fttrderwegee of Kanäleyeteras una of obliquely downward gerioateten Sintarofen-Burohgangskanals before ~ is. In this case, 1st u @ v exerts edition OCE sintering * ·

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Inner honing serving boxes, this channel sw e ige s 17 ¹ inclined transversely to its length obliquely to the horizontal, namely at the same angle as the longitudinal axis of the channel branch ta ¹ having the sintering furnace 13 *.

.Tn Pig. 3 is another one that is advantageous in many cases Furnace arrangement based on their through their channel system leading conveying path explained schematically. The vmtere straight branch 40 of the conveying path is to Horizontal plane 41, which runs perpendicular to the image plane, | inclined. In this preferred embodiment, this branch has the wax stripping oven and its Fb'vderriohtung then runs obliquely in the direction of the arrow upwards. Sound at the end of this branch 40 leads to the right Angled obliquely upwards a short, straight branch 42, in volehem the sinter boxes without changing their inclination rjLtteIs not shown funding, for example niner piston-cylinder unit, upwards to the top dts branching off at right angles, sloping downwards Branches 43 Tjefördert, where they are then by means of a second conveying device in an obliquely downward direction through which in this example the sintering furnace ends Branch 43 will be promoted to Hindu. The branches 40 " and 43 are parallel to each other, so that the sintering boxes are inclined so that they do not rotate over the entire conveying path maintained. This furnace arrangement thus corresponds to the furnace arrangement according to FIG. 1 if it is pivoted by 90 ° about the longitudinal axis of one of its channel branches 17 or 18 « Through the ascending branch 42, the penetration of wax vapor into the sintering furnace itself is prevented then prevented when the branch 40 is directed horizontally or obliquely downwards in the conveying direction. However, this has

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the disadvantage that the inclined position of the sintered boxes changes on their conveying path. by © "bon are to pass through the bottom, the inclination of the Wachsaustrelbofen having branch unless large enough lst _s a penetration of Wachsdaiapf in -abwärts leading branch that sum results in the sintering furnace having branch to avoid. Such an arrangement tonn for thermal convection of the Sohutsgas ^ B can be particularly favorable .

In Pig 4 and 5 there are two further examples of execution inventive furnace arrangements echeiaatiseh based on the represented by the conveying path leading through their canal system »

You embodiment according to Pig. 4 differs from that according to Pig * 3 in that branch 40 of Flg. 3 is pivoted about the Mngsaohee of the branch by 180 ° into the position designated by 40 ". The other branches 42 and 43 and the horizontal" plane 41 are provided with the same reference numbers as in FIG. 3, since they have the same relative position to each other as in Fig. 3 have. The advantage of this arrangement according to FIG. 4 is that the sintering boxes can also be displaced in branch 40 'with particularly low forces, so that the displacement can also be carried out manually by means of a push rod or the like without particularly exertion of force. The one expelled in the wax

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forced wax vapor flows when its specific gravity is greater than the specific weight of the protective gas, not to the entrance of the branch 40 ', but to the Krüpaungsstelle 45 of the conveyor route. He is then of higher learning exposed as if he were to the entrance of the conveyor path 40 ' would flow. The wax vapor is in this pail in the Proximity of the point of curvature 45 from the canal system is expedient discharged together with protective gas. In this arrangement, protective gas can optionally be used both in the vicinity of the Exit of branch 43 as well as in the vicinity of the Branches 40 'are introduced into the channel system, with the entire protective gas then in the trouble of the point of curvature 45 is derived from the channel system together with the wax vapor.

As a result of the right-angled parts of curvature 45 wülü 46 and the resulting parallelism of the branches 40 'and 43, the inclined position of the sintered boxes remains unchanged over the entire conveying path and they also need not be rotated.

In the "variant of FIG. 4" shown in Hg. 5, the branch 40 ^{1 ·. Of the conveying path of the channel system, which has the wax expulsion furnace 12 f} *, and the branch 43 of this conveying path, which has the sintering furnace 13 ", are also on the same axis here - with the sintering boxes both Run through branches 40 »· and 43 in an obliquely downward direction. In order to "avoid the penetration of wax vapor into the sintering furnace 13", a channel-shaped channel curvature with branches 50, 51 and 52 is provided in the channel connecting the two furnaces. All points of curvature 54, 55, 56 and 57 of this

.- ■■. ·. - 22 ~

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EanalsyeteiES ei α wrc Ii © fs

Bie carrion ice cream piles naefe iea Pig · 4 mna 5 asked

towards the AusfatarungeHet

ien feekfeeiX ,, escape into the Zvieig © ■ ferielses Man Tersi © fet therefore 1 Ms 3

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Claims (1)

Claims 1 «Furnace arrangement for sintering objects in sinter boxes under protective gas, with a wax expulsion furnace and sintering furnace each having a passage channel for the sinter boxes, which are connected in series by means of an externally gas-tight connection channel, and the further conveying means for conveying the sinter boxes through their channel system has »characterized in that the passage channel of the wax outlet driving furnace (12; 12 ') in the conveying direction of the sinter boxes • (19) obliquely upwards and the passage channel of the sintering furnace (13j 13') in the conveying direction of the sinter boxes in ... / '. is directed obliquely downward in a manner known per se, and that the duct system has a duct curvature (22; 22 ') leading from the obliquely upward conveying direction into the obliquely downward conveying direction _t which is assumed by the sintering boxes without tipping over into one of the upward movement Ifird wanders through the opposite inclination. - ■ -, 2ο furnace arrangement according to claim 1, characterized in that that the conveying path running through the channel system, ti along which the sinter boxes move, is level at floor level of the sinter boxes. -24- 10988 3/07 7 «- 24 - 3. Furnace arrangement for sintering under protective gas of objects located in sintered boxes, each with a passage channel for the sintered boxes Wax expelling furnace and sintering furnace connected in series by means of a connecting duct that is gas-tight to the outside are included and the further S'örd®mittel sum promote the sinter boxes by their Kanalsyst © ra, in particular according to claim 1, characterized in that between that in a known manner in the Föräerrichtung the silage box, which is directed downwards at an incline and has the sintering furnace, and the canal branch (43), which is the wax stripping furnace having channel branch (40; 40'ι 40 **) of the channel » systems an eanal curvature sw is changes is included., which one of the anal branch having the wax expulsion furnace has angular branching channel branch "(42; 50), its The longitudinal axis lies at least approximately in a vertical plane, 4 * furnace arrangement according to one of the preceding claims, characterized in that all existing Krürara- » place ($ 33.34 54 ', 45.46; 54-57) of the duct system at right angles are. Oven arrangement according to claim 3 or 4, characterized in that the channel branch (40 «j 40 ¹¹ ) having the wax stripping oven is directed obliquely downwards in the conveying direction of the sintered boxes. 6. Furnace arrangement according to one of claims 3 to 5, characterized marked that oils xengeaohee of the the wax stripping oven having channel branch (4O? 4O '| 4O ") Channel branch (42 ^ 0) is directed upwards. 109883AO774 c-7 -.- ■■ - 7. Furnace arrangement according to one of the preceding claims, characterized in that the channel curvature is U-shaped is (Pig / 1, 3, 5). 8 «furnace arrangement according to claim 1 or 2, characterized in that that the misshapen eanal curvature two through a straight channel branch (20) has connected right-angled bends (33, 34) and the Mngsachse this channel branch (20) is directed horizontally, 9. Oven arrangement according to claim 1 or 2, characterized in that the channel curvature (22 ·.) A single one having right-angled Krüanaunesteile (34 "). 10.Ofea arrangement according to claim 9 "characterized in that the longitudinal axis of the ^{channel branch having the wax expulsion furnace (12 9} ) is roughly horizontal" 11 · Furnace arrangement according to one of claims 1 Ms 9, characterized characterized in that the inclinations of the through channels of the Waohsaustreibofens (12) and the sintering furnace (13) are equal to the horizontal. * " I2.0fen arrangement according to claim 11, characterized in that that the Waohsaustreibofen (12) and the sintering furnace (13) are arranged parallel to each other. (Fig. 1). 13. Furnace arrangement according to claim 11, characterized in that that the wax expulsion furnace and the sintering furnace are arranged in parallel one above the other (3? ig. 3). 10 9883/0774 14öOfenattoriainag aaeh buckets d®r
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(12; 12 *) © la ZiifUbrungskanal (14f14 ^B ") vosgesobaltat a Ableittanal (26; 26 ⁽ ) aaebgssclialt © ^ is - tor the for the Slttt © r & ä @ t © a waä © im © XüitalBom® 16 »OfeiiaiioriTaung naoh- Aasprueh 14 oä®r 15 ₉ saiohnet that the ZufttteungslaaBl Rat _e of Ibleitkanal gleiobaohsig with the lwrehga®g§teaiil 'of naobgesobalteten Tongasehaltet% © - © as Ot ₀ thereby g © ^ enn @ © iohfiet on her teflnilictea 16 ¹ , 32 «) ao trained siaä _? that it flows Simtarkäeten through äas Samalaystea under Beitetelt ■ ite®r räuüliehea, 109883/0774 19, furnace arrangement according to one of the preceding claims, characterized in that the inlet for the protective gas near the exit of the sewer system and the The outlet for the protective gas is arranged near the entrance of this channel system (Fig. 1,2). 109883/0774