DE2163202A1 - Annealing furnace - Google Patents

Description

2153202

PATENT LAWYERS

DIPL-ING. HANS BEGRICH · DIPL-ING. ALFONS WASMEIER

REGENSBURG 3 LESSINGSTRASSE 1 0

Patent attorneys, Anbich · Wasmeier, 8400 Regensburg 3, Postfach 11

To the

German Patent Office

8 Munich 2

_i

Telephone 0941/21986 Bayer. State Bank, Regensburg 507 Postal checking account: Munich 89369 telegrams; Begpatent Regensburg

Your sign Your message from

Please indicate in the answer
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^Day 7 Dec. 1971 B / We

Litton Industries, Inc., 360 North Crescent Drive, Beverly Hills,

California 90213

Annealing furnace.

The invention relates generally to annealing and heat processing furnaces and is useful in conjunction with continuously operating ovens of the type known as vibrating beam cookers, which are used to reheat material, i.e. load or insert material such as steel or others Metal plates, blocks, bars, or the like for hot processing corners can be used, whereby a uniform heating through the load should be obtained without it one to be exposed to an annealing temperature for a longer period of time.

Large metal objects such as bars, plates, blocks

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or the like, which are to be referred to as charging material, have generally been heated in multi-zone pusher furnaces, in which the burners were arranged in the zones and provided for heating from above and below. The material is over butted a frame, which is formed by a network of water-cooled beams or support tubes, which are conventionally are referred to as slide rails. This has not yet proven entirely satisfactory by the Slide rail markings in the metal surfaces of the load as a result of the sliding contact between the load and left behind the water-cooled support rails.

Swing-beam type cookers with a moving frame have also been used to heat large metal objects, in which the load is gradually raised from a fixed part of the frame, by a pull of certain Size was moved forward and then lowered so that it rested on the fixed part of the frame, during the moving part of the frame under the fixed part has been withdrawn in preparation for the next advance. Other Vibrating beam type cookers have also been in use where the load is a short distance through a Set of bars is moved forward, then another set of bars is raised while the first set of bars is retracted and finally back down onto the first set of bars, the cycle moving forward of the load is repeated through the furnace. In ovens of this type, the one containing the movable frame part has it Mechanism made difficult to provide a satisfactory furnace in which a load from below, from the Sides and can be heated from above. As a result, it has become necessary to keep the load for a long time

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Heat in order to obtain an even temperature distribution through the entire load. Efforts, swinging beam-like Providing ovens with appropriate lighting from below, as well as from above and the sides, has to be provided in the construction a suitable support system of suitable strength led to difficulties in securing the load Support and move through the oven while simultaneously applying and distributing heat evenly to all Sides including the underside of the load should be reached.

The previous mobile rack or swing beam furnaces also had difficulties with an effective seal result in the areas where the structural component supporting the frame passes through the lower part or floor of the furnace. Another problem with the known ovens has been to prevent cold air from entering through the exhaust opening and could cause uneven temperatures in the load prior to discharge.

Thus, there was a need for industrial furnaces that would overcome the disadvantages of the known annealing furnaces and heat processing furnaces be avoided and which are able to heat the items to be served so that a uniform temperature distribution is maintained throughout the workpiece without prolonged annealing by the application of heat evenly on all sides of the service items as they are moved through the furnace. In such ovens, the load-carrying systems must be strong enough to handle the relatively long distances or additional To bridge supports between the ends of such systems .

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In general, the invention provides an annealing furnace with a frame which is provided with support systems for the load to be heated, with at least some of the support systems consisting of bridge-shaped components of pipes cooled by a flow medium, and each bridge-shaped component the distance between its end positions bridged. If the annealing furnace has floor or lower walls which determine different and special heat zones, the end positions of the bridge-shaped components can be supported by two mutually adjacent lower walls of the furnace. Each bridge-shaped component expediently consists of a lattice frame of a plurality of tubes which are cooled by a flow medium and which occupy a common, essentially vertical plane. "Lattice frames ¹¹ are to be understood as meaning all open framework frames of structurally interconnected reinforcement elements in which openings are left between the individual elements, which consist of the cooling tubes that form the support systems.

Thus, according to the present invention, there is an annealing furnace with one of stuttering devices for the load to be heated Assembled frame provided, in which at least some of the support devices have the shape of a lattice frame or open frame and each supported at its end points and by a plurality of fluid-cooled Pipes is composed, which form a common, substantially vertical plane. Thus, by the invention An annealing furnace can be created in which at least some of the support devices are made of bridge-shaped components of fluid-cooled Pipes exist, each bridge-shaped component bridges the distance between the end positions of the component and the end positions of two mutually adjacent lower walls

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of the furnace.

According to a further development of the invention, the arrangement is made such that in each lattice frame the fluid-cooled Tubes are bent, a deeper tube at least one higher tube at bending points and between the End points supported. In particular, at least some of the intermediate tubes in turns up and down within the be bent in a common plane and mechanically connect the top tubes to the bottom tubes of a lattice frame.

If the annealing furnace is to be used as a vibrating beam hearth or furnace, it has proven advantageous to use the supporting devices so train that at least some of them in groups to form pairs of transversely adjacent Support systems with jointly bent pipes are summarized, which interconnections between the support devices of a couple. The end positions of a support device are expediently provided by movable carriages with internal channels supported, which for a coolant connection between the tubes of the mutually adjacent support devices care for. In more detail, a movable carriage can provide a common support for the two support devices Pair. With the exception of the support device at the feed and discharge end of the furnace, they also share Support devices which are mutually adjacent in the longitudinal direction through the furnace, a movable carriage, which thus supports at least two end points of special adjacent support devices.

Since the moving carriages are used as feed support devices for the load to be heated is used is any

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Carriage preferably horizontally movable to and fro via an opening in the horizontal upper part of a lower wall of the Oven arranged, the dimensions are made so that a car has a cover for the opening regardless of his

Location forms. The carriages can be arranged on rollers, which in turn are arranged within the openings. An annealing furnace incorporating some or all of these features can be designed to function as a vibrating beam hearth Driving devices for at least some of the support systems can be operated. Such vibrating beam cookers can continue to have at least one pair of adjacent one behind the other Support devices are provided which can be operated so that the support device of the pair, which closer to the guide end of the furnace is located, executes a forward stroke when lifting during a movement phase in which the mentioned feed support device is lowered in the direction of movement in order not to support any load measured in the direction of movement of the goods through the furnace.

Furthermore, in a further development of the invention, an annealing furnace of the type described is provided which has at least one smoke outlet duct in the full heat zones of the furnace near the discharge opening, which is supposed to collect exhaust gases and which means for generating it of negative pressure within the flue duct, combined with the arrangement of burners, which so are arranged that they fire in the direction of movement of the load and thereby remove the exhaust gases by suction and at the same time substantially prevent cold air from entering the oven through the exhaust port from further entering the oven. Preferably the one or more smoke extraction ducts is or are after

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directed downwards from the discharge opening.

In one embodiment of the invention, the support devices for the load, which are to be generally referred to as "carriers", of a plurality of spaced lower or bottom walls which extend upwardly from the bottom of the furnace. the lower walls delimit a number of lower heat zones. The stove is fired by burners in the walls below and are arranged in the upper walls. A first series of feed beams, i.e. support devices, according to the invention is provided, these beams being supported on the lower walls by carriages which extend in the longitudinal direction Move back and forth on the walls via slots, giving each carriage a transverse seal, i.e. a cover forms for the slot. Furthermore, those carriers that form a second row and are lifting or lifting carriers are on the lower walls arranged vertically to and fro, both rows of supports are operable in cooperation to To convey the load through the furnace in stages.

On the other hand, a first row of such supports, i.e. absein support tube components, can be fixedly arranged on the lower walls the beams of a second row, supported on the lower walls by similar carriages, are both longitudinally as well as arranged movable in the vertical direction, the combined system having a different arrangement for Moving the load forward gradually through the furnace.

In a further embodiment of the invention are a back-fired lower full heat zone and a descending train

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near the discharge end of the oven is provided for the heat point in the direction of movement of the load into the zone and cause hot exhaust gases to heat the load until it is discharged from the furnace.

In a further embodiment of the invention includes a Load-carrying frame a plurality of movable load-carrying devices, each of which is a first and a second section that is interconnected and reciprocable both longitudinally and vertically Direction are arranged in the furnace. The two sections can, although they become one with each other horizontal movement are connected, independent relative

en
perform vertical movement / with reference to each other. The first section includes an upper tubular member and a lower tubular member connected by at least one intermediate tubular member to form a strong, water-cooled beam. The frame also contains fixed supports. The supports, the so-called carriers, are driven so that the movable supports lift and advance the load and gradually convey it through the furnace, and therefore the spacing between the loads is widened, as will be described in detail below. The furnace includes a preheat zone through which the first sections extend and flue ducts connected to the preheat zone below the first sections and hot gases over the top of the still tightly packed loads to the zone below the feed end of the furnace and then back pulls down below the load in order to heat its lower sides.

The invention is shown in the drawing, for example.

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Figure 1 is a schematic vertical longitudinal section through an annealing furnace according to the invention.

FIG. 2 is a partial horizontal section along the line 2-2 of FIG.

FIG. 3 is a cross-section along line 3-3 of FIG.

Figure 4 is a cross-sectional view taken along line 4-4 of Figure 3 showing the adjacent ends of two feed beams.

Figure 5 is a cross-section through the leading end of the furnace of Figure 1 showing the apparatus for moving the feed carriers.

Figure 6 is a vertical longitudinal section through one end of a furnace and shows another embodiment of the furnace according to the present invention.

Figure 7 is a cross-sectional view taken along line 7-7 of Figure 3 showing the adjacent ends of two lift beams.

Figure 8 is a vertical section through a further embodiment form of the invention and shows the adjacent ends of two solid beams resting on top of one lower wall are arranged.

Figure 9 is a cross section through another embodiment according to the invention and shows the adjacent ends of two both longitudinally and vertically Direction of movable beams, which are arranged on a lower wall.

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FIG. 10 is a cross section along the line 10-10 of FIG. 9.

FIG. 11 is a horizontal section through a further embodiment an annealing furnace according to the invention.

FIG. 12 is a vertical longitudinal section through the annealing furnace according to FIG. 11.

Figure 13 is a cross section taken along line 13-13 of the Figure Figure 14 is a cross section taken along line 14-14 of the Figure

FIG. 15 is a front view taken along line 15-15 of FIG.

In Figures 1 to 5 and 7 of the drawings, an annealing furnace is shown in different sectional views, which with a Entry, i.e. feed end 12, and an exit, i.e. discharge end 13 is provided. The oven is divided into a plurality of heating zones by a plurality of suitably spaced divided upper and lower walls 21 and 22, which extend across the furnace over its entire width. the lower walls extend from the top, i.e., upward from the bottom of the furnace, and the upper walls extend downward from up by the stove.

In the embodiment shown in Figure 1, the furnace into upper and lower primary or preheat zones 14 and 15, upper and lower secondary heating zones 16 and 17 and upper and lower Full heat zones 18 and 19, in which the workpiece is exposed to an annealing temperature for a long time, divided. The furnace will by arranged in the walls of the lower transverse walls 22

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Bottom end burners 23 and in the walls of the upper transverse walls 21 arranged upper end burner 24 heated. The bottom and top end burners 23 and 24 are arranged so that the heat in In the direction of the feed end of the furnace. which means in a direction opposite to that in which the load to be heated 2o move through the oven want.

As shown in Figure 3 with respect to the bottom burners, the bottom and top end burners 23 and 24 are in bulkheads spaced along across the width of the oven to provide even heat both above and below the load 2O to be provided over the entire width of the furnace. In Figure 1, the upper full heat zone 18, the longer time is exposed to an annealing temperature, heated by a plurality of conventional burners 25, which are located on the cover of the Zone and send the heat down into the zone. If desired, this upper zone 18 can also be heated by end burners.

During the furnace of the present invention utilizing the lower and upper end burners 23 and 24 and the top burners 25 works satisfactorily in the full heat zone, side burners can also be added. By providence of burners in each zone, the temperature can be regulated individually in each zone as desired. The burners can be from common design and use either hot or cold air.

The furnace is provided with an exhaust manifold 26 (Figure 1) at its feed end 12 for removing exhaust gases from the furnace. The exhaust collector 26 is with a chimney through a smoke duct connected in a conventional manner. The smoke outlet duct

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can with a gas preheater to utilize the smoke exhaust gases be equipped to preheat the combustion air. In modification · to this, the smoke exhaust gases can be in any other used appropriately or simply released into the atmosphere.

A load 20 or workpiece to be heated is fed through the furnace from the feed end 20 in the longitudinal direction the discharge end 13 is moved forward by a movable frame, which consists of a plurality of feed beams in the form of an open or lattice frame 32 and lifting beams is made in the form of an open or lattice frame 33, each of which is formed from water-cooled pipes.

As shown in Figures 1, 3, 4 and 7, each feed beam 32 includes an upper tubular member or tube 34, where a like upper tubular member or tube is part of a fixed, i.e. fixed, support 3J? forms. The top Tubes 34 run straight their entire length and provide support for the load in the furnace. Either of the two Types of beam has a lower tubular member or tube

35, a first intermediate tubular member or tube

36, a second intermediate tubular member or tube 37 and a third intermediate member or tube ö8. Each upper tube 34 is provided with a plurality of mutually spaced support buttons or rails 39 for supporting the Provided in the furnace to be heated charging material, as can be seen from FIGS. 3, 4 and 7. These support buttons can made of chrome-nickel alloy material which are welded to the top of the tubes. All pipes are together at spaced apart locations to form a rigid, load bearing support system, referred to herein as

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Beams, connected by great length. The lowest pipe section 35 - * each beam is generally V-shaped, lowering it in the middle than at either end. All pipes are with covered with a suitable insulating material.

The intermediate tube 36 of each beam extends from one end down to the tube 35 and then up to the Pipe 34, then runs in a sharp turn between the lower pipe 35 and the upper pipe 34 over the entire length of the And connects the upper and lower tubes together at a fixed distance. The intermediate tube 37 of each carrier goes from one end of the beam (Figure 1) and connects the intermediate tube 36 and the upper tube 34 at intervals on one Part of the lengths of tubes 34 and 36. Likewise, on the opposite side of the beam, tube 38 extends from that one end to different locations between pipe 34 and pipe and connects the two pipes over part of their lengths. if When the beam 32 is a single beam, the ends of the tubes 37 and 38 are joined together to form a continuous track for the flow of cooling water from one end to the other. When two feed carriers 32 are connected to each other and together one Form a fixed unit forming pair, as shown in Figures 2 and 3, traverse and extend the Pipes 37 and 38 between the two beams of the pair and firmly connect the upper parts of the two beams together. Consequently Each beam forms a rigid, open frame, also called a lattice frame, which considerably reduces the use of ' Heat on all parts of the load, especially including the use of bottom burners 23, their function is not impaired by the support systems for the load.

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As shown in Figure 7, the lift beams 33 have the same general design of tubing as the feed beams 32 except that the ends of the upper tube 34 on each lift bracket extend outwardly at the top and then curve back downwards into the support component, as described in more detail below is.

In the embodiments of the invention according to Figures 1 to the end beam is a single lifting beam while the rest are borrowed Inter-end carriers in pairs of interconnected feed carriers 32 and alternating with pairs of lifting beams 33 connected together are combined, as shown in FIG. Thus, the feed carriers have 32 and lifting beams 33 alternately spaced in pairs across the width of the furnace, i.e. in an interdigitated form.

Each pair of feed beams 32 of the movable frame are movably supported for reciprocating longitudinal movement on each bottom wall 22 by a carriage or support section 41 made of suitable refractory material. As shown in Figures 3 and 4, each carriage 41 is provided in its lower part with a tubular frame 42 which extends around the lower outer edges of the carriage and also across the width in the center of the carriage. The individual tubes of each girder are connected to the frame 42 not only for rigid support of the girder end, but also to serve to supply water or another cooling liquid to the tubes of the girders. Water is supplied to the frame 42 by suitable connecting means.

It can be seen from FIGS. 3 and 4 that each carriage 41

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is movably supported on the lower walls 22 by means of rollers 43 which are fastened to horizontal rails 51 Bearings are arranged, which in turn are supported by fixed columns 52.

Each carriage 41 operates longitudinally over a slot-shaped opening 44 cut into the refractory cover on the upper side of the transverse wall 22 of the lower zone. The carriage 41 is large enough to cover the edges of each opening 44 and to provide a relatively tight fitting, transverse, horizontal cover for the opening which prevents filings from falling into the apparatus and structure below the top of the bulkhead 22, as well as preventing heat from escaping from the oven through the opening. In addition, the sealing effect achieved by the cover car reduces the amount of cold air entering the interior of the oven through openings 44 in the walls. As shown also in Figure 4, each carriage 41 is longer than the length of each slit-shaped opening 44, and allows a reciprocating longitudinal movement of the carriage in the longitudinal direction of the O £ ert.s the opening _f without exposing any part. Each opening 44 is provided with a water-cooled tubular frame 45 around its upper edges.

According to Figure 7, each lifting beam has as mentioned above is also a plurality of individual tubes which come together at their ends and are firmly connected by a sleeve 46 are. The ends of the tubes of each lifting beam as well as the sleeve 46 extend through an alloy sleeve 47 in a further opening 48 in the lower transverse wall

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The sleeve 47 extends over the surface of the lower transverse wall 22 in a cover 49 which over the tubes of the Carrier lies. The cover 49 and sleeve 47 act as a seal to prevent filaments from entering the lower frame fall. A bearing 50 attached to the tubes of each lifting beam 33 under the tubular sleeve 46 is rigid with a bearing Frame 53 connected, which is made of interconnected rails, which in the longitudinal direction the furnace length and across the width under the lower zone transverse walls. The frame 53 is through described below Means for lifting the carrier 33 by reciprocating the Sleeve 46 is movable within sleeve 47 in each lower transverse wall 22. The ends of the tubes of each lifting beam 33 are connected to water supply means or another suitable cooling medium.

As can be seen from Figure 3, the frame 53 ^ is strong and wide flange pillars 54 and tubular side pillars 55 supported. The pillars 52 are at the bottom of the stove, as shown in Pigur 3 and can be crossed out to ensure lateral stability of the furnace structure. The wide flange columns 54 form the main vertical support members for the frame 53, which the lifting beam 33 is actuated. The tubular side columns 55 are held in place by suitable guides or bearings 56, which are attached to the columns 52 and only allow movement in the vertical direction.

Both movable columns 54 and 55 are fixed to their lower ones

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Ends arranged on lifting rails 61, which are pilot at a distance on the inside on each side of the lower transverse walls 22 _ώ see and extending across the furnace, as in the ^x '""' - Figures 3 and 4 is illustrated. Each lifting rail 61 is supported on rollers 62 which are arranged on angle levers 63. The bell cranks are connected by a tie rod 64 attached to a pivot arm 65 which in turn is connected to corresponding power operated drive means such as hydraulic cylinders 66. Hydraulic cylinders 66 are provided on each lower wall and provide lifting force along the length of the furnace. The cylinders may be actuated by a common pump and synchronized by known means to allow an even lifting along the length of the furnace. While a hydraulic drive system is shown in the drawing, it will be understood that suitable mechanical drive means such as eccentrics and crank arms driven by suitable motors can also be used.

The feed beams 32 can be accessed from the discharge end of the furnace from, as shown in Figures 1 and 5, are driven by hydraulic cylinders 67, each directly with the bottom of a carriage 41 is connected to the discharge end of each feed beam by suitable bearings 68. Everyone a plurality of such cylinders can be driven and synchronized by a common pump in order to achieve simultaneous, to achieve even back and forth movement in the longitudinal direction of the furnace of all feed carriers.

The floor-fired area of the furnace is divided into zones of equal length by the transverse walls, as shown in FIG is. This makes it possible that the individual carrier so

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be made so that a beam section spans each zone, thereby allowing greater uniformity of parts for easier maintenance and repair.

The furnace can be fitted with side observation doors, 'which are arranged below the lifting height of the feed carriers. This arrangement allows the furnace to operate under positive pressure is operated below the Materxalabstützlinie and close to zero to slight negative pressure on the transverse seal, which is effected by the carriage on top of an opening in each wall. These near atmospheric pressures at this one Height reduces the amount of air around the carriage seal is infiltrated without applying excessive pressure to the observation door.

During operation of the embodiment of the invention according to FIGS. 1-5 and 7, a charge 20 to be heated or the load 20 to be heated is transferred to the movable frame at the entrance 12 of the furnace by appropriate means. When the furnace with the operation begins and the movable frame forming feed and lift bars begin to move, there is the lifting support 33 in a lower position mil W, the feed is supported only by the feed carrier 32, which in a retracted position are located. When a work cycle is started, the feed carriers move forward a certain distance and stop, whereupon the lift carriers are raised and the load well removed from the feed carriers. The feed carriers then throw retracted into their original position. Then the lift beams are moved down to lower the load back onto the infeed beams, and the cycle is repeated more times, thereby moving the load lengthways

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move through the oven in one intermittent motion.
During the operation of the furnace, the load is
through the furnace in one to the flow of the heated gases through
moves the furnace forward in the opposite direction. The hot exhaust gases move to the inlet end 12 of the furnace and escape through the exhaust manifold 26.

The lifting beams 33 operate continuously at a constant rate
Frequency with a perpendicular shift, which is the same
is distributed above and below the height of the feed beam. With this method, the points of support contact between the load and the lifting and feed carriers are changed and thereby each support point of the load
the direct furnace heating exposed for half the time in which the load is in the furnace. This is a great advantage in that it lowers and even often completely eliminates any temperature differences between the points at which the load and the rest of the load are supported. Thus, all of the heat is transferred essentially evenly to all surfaces of the fabric. The use of support systems in the form of beams according to the invention as load support members in the furnace even improves the transition from to a great extent
Heat on all surfaces of the load as the carriers
Form an open grid frame below the load, which means better exposure to the heat.

When operating the furnace of the present invention for reheating for example a steel plate, a typical temperature for the upper and lower primary zones would be 1,370 ° C,

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a typical temperature for the upper and lower secondary Zone would be 1,315 C, while a typical temperature for the upper and lower full heat zones would be 1300 ° C. One Load on load would normally pass through the furnace at a speed of 10 to 21 meters per hour.

Another embodiment of the furnace according to the present invention The invention is shown in Figure 6, which has an additional full heat zone or zone in which the load is longer Time of an annealing temperature is included. In the The embodiment according to FIG. 6 is a primary preheating zone 18A provided above the lower transverse wall 22 in front of the upper preheat zone 18. The primary preheat zone ISA is made up of a top wall 71 which extends downward from the cover of the oven.

In the arrangement according to FIG. 6, the lower preheating zone 19 is heated in a direction which is the opposite of that in comparison to FIG the other lower zones, which arrangement is described by the noting that they are opposed by end boards 72 is fired because the hot gas flow in the same direction and is directed generally parallel to the path of the load through the furnace. Both the primary upper preheat zone 18A and cLe upper preheat 18 are heated by burners 25 which are arranged in the cover of the furnace. The order the primary upper preheat zone 18A is selected so that the exhaust gas from that zone is discharged into the upper secondary zone 18 from where it extends in the direction of the feed end 12 (Figure 1) of the furnace moves. Exhaust gas from the upper full heat zone 18 is discharged along the smoke exhaust duct or exhaust gas from the lower full heat zone 19 in a smoke exhaust gas duct 73, which

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is arranged near the discharge end 13 of the furnace.

The smoke exhaust duct 73 is operated at negative pressure, around a flow of heated flue gases from the full heat zones 18 and 19 near the discharge end of the furnace across the to cause the front edge of the load passing through. It should be noted that the ends of the beams are at the discharge end of the furnace extend outwards, i.e. beyond the smoke exhaust duct 73. The flue causes also that cold air, which could seep in through the discharge end, is drawn in before it is drawn in with the heated air through the The furnace comes into contact with the load. The exhaust gases can from the smoke exhaust duct 73 through a special chimney be discharged. A plurality of exhaust ducts or cascading flues 73 can be arranged across the width of the furnace in such a way be made that the drive cylinder 67 (Figure 5) for the feed carriers are arranged between the smoke exhaust ducts can be. The smoke exhaust ducts 73 are between the discharge end 13 of the furnace and the lower full heat zone 19 in a height below that of the carrier which forms the movable frame.

The purpose of heating the lower preheat zone from the rear and venting gas at the exhaust end of the furnace by means of smoke exhaust ducts 73 consists in the cold air, which would normally enter through the furnace exit door 13, directly down into the smoke ducts and out of the Eat while hot gases flow continuously over the load. This ensures that the load in the The furnace is completely surrounded by hot gas until it is discharged.

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Another embodiment of the invention is shown in the figures

9 and 10 shown. The furnace is similar in design to the embodiments of Figures 1-7 with the exception that the Frame is made of insulated solid, i.e. fixed supports alternating with insulated beams, which then must be movable both in the longitudinal direction and in the vertical direction in the Ofer, in order to allow the load to pass through it step by step « to be able to promote. The fixed support can be a carrier, which is in the manner of a feed carrier 32 with the exception is made that the carrier is fixedly arranged at its ends on the lower wall in the manner shown in FIG is. As a modification to this, the fixed support can consist of individual, tubular members or tubes 81 (FIG. 10), which are supported by vertical support tubes (82) extending from the bottom of the furnace and from the bottom walls in the The spaced-apart points extend along the entire length of the furnace, the latter fixed support is similar in structure to that, as they are used in the existing pusher ovens.

FIG. 10 shows the fixed, water-cooled support tubes 81 alternating with pairs of interconnected, water-cooled ones Carriers 83 which are movable in the longitudinal direction and vertically. The carriers 83 are the Anhel3e ™ in their construction Carriers 33 of the embodiment described are the same. As in fig-

10, two beams 83 are connected to each other by intermediate pipes 38 connected, which are there to form a rigid unit between. The ends of each pair of beams 83 extends through a heat resistant covered carriage 41, which in the longitudinal direction in and above the opening 44 in each lower wall 22 similar to that described above in connection with the embodiment

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according to Figure 1 to 7 described movable is-t.

The ends of the individual tubes of each carrier 83 are rigidly connected to one another by a sleeve 46 which extends perpendicularly through an alloy sleeve 47 is movable which extends through and over the top of the carriage 41. One attached to the pipes Cover 49 forms a seal with the sleeve 47, • to prevent filaments and other contaminants from entering the part of the furnace below can fall.

The tubes of each carrier 83 extend through the carriage 41 downwards and are connected by a bearing 50 to another frame 84 which forms the base frame of the trolley. frame 84 is mounted on rollers 43 for a longitudinal movement of the furnace, which are arranged on a bearing 53 by suitable bearings, which is vertically movable by a lifting device similar to that used in connection with the embodiments according to Figure 1 to 7 is described. The supports 83 are thus for independent vertical movement through the sleeves 47 ia the carriage 41 as well as arranged for longitudinal movement through the furnace.

Each carriage 41 is of sufficient width and length and extends over the sides and ends of the opening 44 and forms one horizontal transverse cover for opening during longitudinal movement of the carriage. The carriage 41 is supported by rails 85 (Figure 10) supported by a lower leg which rests on rollers 86 which are fastened to a wall 22 by suitable bearings Rail is supported. The upper part of the carriage 41 is secured to the rail 87 against vertical movement Arms 88 held in place and extends over the lower

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Legs of the rail 85 shown in Figure 10 to form a guide unit therewith. Here carrier 83 are in the Moved longitudinally by cylinders which are attached to the pan frame at the discharge end and to the frame structure 84 are connected at the end in a manner corresponding to the embodiments of Figures 1-7.

When operating the embodiments according to FIGS. 9 and 10 the working cycle is started with the load 20 resting on the fixed supports 81 and the frame pairs and the carrier pairs 83 lowered and towards the discharge end to be arranged. The beams 83 are then extended lengthways towards the feed end of the furnace moves until they reach a certain position. At this time, the carriers 83 are raised up to remove the load lift off the fixed supports 81 and then move them longitudinally towards the discharge end, until they have reached their outermost forward position. The carriers 83 are then returned to deposit the goods to be sent on the fixed supports 81 and continue in their starting position lowered in preparation for the next work cycle. In this way, every load or batch is passed through the furnace moved from the feed end to the discharge end.

Another embodiment of the invention is shown in Figure 8, which shows an annealing furnace in which the frame consists of a plurality of solid supports attached at their ends for example, the lower transverse walls 22 are supported by appropriate supports, as it is with reference to the imple mentation forms of Figures 1 to 7 has been described. These carriers shown in Fig. Are made of a plurality of isolated,

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tubular members, ie tubes, as in the feed beams 32 of the embodiment form according to FIG EADERSHIP 1 to 7 described ^{rigidly> r} connected to each other. In the embodiment according to FIG. 8, however, the individual tubes of each carrier are supported at their ends by the heat-resistant upper part of the lower partition wall 22 and go through this. The tubes are rigidly connected to a steel structural framework 92 within the lower wall. The ends of the tubes of each beam 91 are conventionally connected to a source of water or other cooling liquid. The upper tube 34 of each carrier 91 is provided with a solid wear bar 93 of suitable material for supporting the load. The furnace shown in Figure 8 is operated as a pusher furnace in which the load is placed on the upper tubes 34 of the carrier 91 and pushed through the furnace in a known manner.

Another embodiment of the present invention is shown in FIG Figures 11 to 15 shown. The furnace according to this execution form is with an infeed end wall 110 and an outfeed end wall 111 provided. The furnace is of the type which conventional means for feeding billets into the furnace at the feed end through a feed opening 121 in the furnace side. Jn In the same way, the bars or the other load through a discharge opening 123 removed in the oven side by conventional means in a known manner.

In Figure 12, the oven is divided into a plurality of upper heating zones. The heating zone 112 near the feed end wall IiO des Oven is a primary, i.e. preheating, zone. After the preheating zone 112, a first heating zone 113 is present, which between a upwardly leading cover part 114 of the top of the furnace and a downwardly directed cover part, which is a wall 115

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forms at the other end. A second one, protruding downwards top wall 116 divides the remainder of the furnace into a second heating zone 117 and a final zone 118 in which the charge is exposed to an annealing temperature for a prolonged period. The oven is at least in the last preheat zone 118 and the first

and second heating zones by a plurality of roof burners 119 heated. Although it is not essential for the stove to operate, roof burners can also be used if desired can be used in the preheat zone 112. The stove is on the side Observation doors 122 provided, which in the side walls of the furnace are arranged approximately at the level of the furnace frame.

The frame is formed by a plurality of alternating fixed and movable supports which work so that the load is moved gradually through the furnace. The solid supports in the preheating zone 112, which are partially Extending into the first heating zone 113 at the feed end of the furnace are a plurality of spaced-apart slide tubes

125 (Figures 11 and 14) formed, which by suitable casting

126 are supported, which, as shown in Figure 14, are arranged on the heat-resistant support pier walls 127 made of brick. The castings 126 distribute the load from the slide tubes evenly across the top of the walls 127. If desired, solid slide tubes 128 can be attached to the tops of the slide tubes 125, for example by welding _; ^{to support} the load in the oven. The slide tubes 125 and support pier walls 127 extend from the feeder; end of the furnace partially into the first heating zone 113.

Starting from approximately the end of the sliding tubes 125, the stationary supports are made of solid, heat-resistant material formed, as by the reference numeral 130 in FIGS

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is displayed. The supports 130 made of heat-resistant Material extend from the center in the first heating zone 113 to the exhaust wall 111 of the furnace.

The movable systems of the frame, which support the load, have a first and a second section which are connected to one another. As shown in FIGS. 11 and 12, the first section of each movable support system consists of a carrier 131 which is made similar to the feed carriers described in connection with the embodiment according to FIGS. Thus, each support 131 is from an upper tubular member or tube 132, a lower tubular member or tube 133 _s, a first tubular intermediate member or tube 134 which winds between the tubes 132 and 133 and is fixedly connected thereto, a second tubular intermediate member or tube 135, which is located between one end of the tubes 134 and 132, and is formed a third intermediate tubular member or tube 136, ^ slches between the other ends of the Drill 134 and is 132 »the tubes 135 and 136 are tubular by four © intermediate ¹ = · Links or pipes 137 connected, as shown in FIG. The individual tubes are firmly connected to one another at intervals along their entire length to form a water-cooled, load-carrying carrier. The pipes are covered with insulating material to reduce heat losses. The tubes of each carrier 131 are connected to water or other cooling liquid supply means.

The individual tubes forming the carrier 131 are connected to one another outside the feed end wall Ho of the furnace by a sleeve 138 firmly connected. The carrier is supported outside the feed end of the furnace by a lifting device 139,

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which is described in detail below. The ends all of the supports are outside the feed end of the furnace connected to one another and stabilized in a horizontal plane by bolts or tie rods 129.

The second section of each movable support system includes a movable, refractory rail 141. Each Heat-resistant rail is provided at its inner end with a slot 142 (Figure 11}, which extends from the top extends through to the underside of the rail. As can best be seen from Figures 11 and 14, the interior is End of each carrier 131 arranged so that it is in a corresponding slot 142 but freely in the vertical direction movably protrudes. It can be seen from Figure 12 that the inner ends of tubes 132 and 136 of each beam 131 is received by a vertical guide 143 / which is arranged on a rail 144, which is the heat-resistant Rail 141 is supported. The vertical guide 143 allows the carrier 131 to independently move in a vertical direction with respect to one another to move on the refractory rail while holding the carrier and rail together for mutual longitudinal movement, i.e. to move as a single unit in the longitudinal direction of the furnace. Since there is no relative longitudinal movement between the carrier 131 and the heat-resistant rail 141 is present, the slot 142 in the rail can be designed so that that it forms a tight fit around the end of the carrier.

Each support 131 is at one end outside the feed end of the furnace from deaa elevator 139 and at its other End supported by a lifting device 140 as shown in Figure. As Figure 15 shows from which particular

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the lifting device 139 can be seen, each of the lifting devices 139 and 140 has an upper roller 146, which is supported by suitable fastening arms 147, which are arranged on a frame 148 which extends across the width of the furnace. The frame 148 is spaced supported by a plurality of rollers and bell crank-like devices 149 which are fastened in a connecting rod 150 are, which in turn by appropriate power-operated drive means such as a hydraulic Zy.linder 151 is operated. Thus, by means of two lifting devices all carriers 131 driven simultaneously in the vertical direction.

As can be seen from Fig. 12, the rails 144 supporting the heat-resistant rails 141 are on a plurality of Rollers and bell crank-like devices 153 are arranged, each of which is attached to a connecting rod 154, which in turn is actuated by corresponding, power-operated drive means such as hydraulic cylinders 155 will. A plurality of hydraulic cylinders and jacks are provided, each of which is under a heat-resistant one Rail 141 is arranged across the width of the furnace and in associated motion for lifting all heat resistant Rails are driven at the same time. In addition, during an operating phase of the movable support system, the Lifting device for the heat-resistant rails assigned lifting devices for the carrier, so that the heat-resistant Rails and carriers are raised simultaneously at the same speed in a manner described in detail below can be.

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Each refractory rail 141 and associated support unit 131 is driven longitudinally through the furnace by suitable powered drive means such as hydraulic Cylinder 156 is moved, which is attached to the bottom of the furnace by support means arranged and with the associated rail 144

underneath a heat-resistant rail 141 by a swing arm device 157 according to Figure 12 connected /; All hydraulic Cylinders 156 / associated with each other around all of the heat-resistant rails 141 and beams 131 at the same time in the longitudinal direction of the oven. Conventional waterproofing seals 158 are on the inner end of each refractory rail and placed near the inner end of each beam to prevent that heat can escape from the oven and cold air can enter the oven.

In Figure 11, alloy buffer castings 161 are embedded in refractory wall 110 at the feed end of the furnace just above the rack to prevent the incoming load from hitting the wall. In addition, hydraulic cylinders 162 in the same end wall 110 are straight. disposed above the rack, to push the feed material at the feed end forward to all batches of the loading schickungsgutes W tightly against one another to provide that the first section of the movable chamber load-bearing system of the frame over the length of the sliding tubes 125 or the carrier form.

As shown in Figures 12 and 13, the inner bottom end of the preheat zone 112 is with descending flue gas channels 165 provided, which are operated with negative pressure, daiaii the heated gases from the top of the preheat zone move horizontally across the top of the tightly packed feed

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Move batches towards the feed end of the furnace, then down into the space between the feed end wall of the furnace and the end of the packed feed batches and then horizontally below the bottom of the batches for heating their lower sides. The open, i.e. lattice frame of the movable Carrier 131 greatly facilitates the flow of heated gases around and below the load. on in this way, the loading batches are heated on both the top and the bottom and thus an undesirable one Temperature difference between the top and bottom of the batches eliminated what is usually a throw which results in batches. In addition, the heated gases are used more efficiently in that the cold charge batches heat from the combustion gases both at the top as well as take off at the bottom. The exhaust gases from the descending flue gas outlet 165 can be removed from the furnace by appropriate means Food to be carried away.

Operation of this embodiment of the invention processes billets on the order of 10 seconds by 12.5 cm, although of course other types and sizes of charge batches can be heated in the furnace. Initially there are. the heat-resistant rails 141 and the supports 131 generally their lower position in the direction of the discharge end wall A ₁ IG. A pack of 4 to 6 10 by 10 cm billets is then fed through the feed opening 121 into the side of the furnace so that they are carried by the slide tubes 125. The hydraulic cylinders 162 then push the billets of the pack forwardly around all of the billets in the furnace along the length of the slide tubes 125 and carriers 131, leaving a space between the infeed end wall 110 of the furnace and the end of the tightly packed billets. The rails and supports are then moved 20 cm in the longitudinal direction towards the feed end of the furnace and then come to a rest position. At this point will be

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the rails and girders are raised together at the same time, thus removing all of the loading batches in the furnace from the stationary ones Supports, i.e. sliding tubes 125 of the frame. The loaded rails and beams then move towards the discharge end of the furnace by reaching a horizontal displacement of Io cm and then stand still. Then they stay refractory rails 141 in a raised position while the carriers are lowered to accommodate the loading batches of the The preheating zone in turn comes to rest on the stationary supports, namely the slide tubes 125 or supports 130 when they are moved forward enough. In this position, the heat-resistant rails and the lowered ones move Carriers then an additional 10 cm in the direction of the discharge end of the furnace and come to a standstill again. The heat-resistant Rails are then also lowered to accommodate the loading batches lower back onto the fixed supports of the frame and return to their original lowered position, whereupon the working cycle is repeated.

When the work cycle is completed, the bars are on the Heat-resistant rails 141 in the heating and preheating zones advanced 20 cm while those supported by the beams 131 Ingot to the point where the beams enter the end of the slots 142 at the end of the refractory rails 141, have only moved forward 10 cm. Thus become at the junction between the beams 131 and the ends of the refractory rails 141, the closely packed adjacent ones Bars separated by the independent lowering movement of the beams and then 10 cm by continuing the 10 cm forward movement of the heat-resistant rails 141 as shown in FIG. 12 is removed. This 2: 1 stroke ratio has the consequence

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that the billets run through the furnace at speeds such that they take approximately 43% of the total time, both at the Spend upper as well as the lower part in the preheating zone 112 during heating, which takes up only 27% of the furnace length.

As the ingots travel from the beams 131 to the refractory rails 141, they continue through the furnace the horizontal and vertical movement of the refractory rails 141 moves until it reaches that of the discharge end wall 111 The next area of the furnace can be reached from where the ingots are then fed through a side unloading door using conventional devices 123 can be removed.

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Claims (17)

L / p 7260 -34- December 7, 1971 B / We patent claims 1. Annealing furnace with a frame composed of support devices for the load to be heated, characterized in that at least some of the support devices consist of bridge-shaped components (32, 33) of fluid-cooled tubes (34, 35, 36, 37, 38), and each bridge-shaped component (32, 33) spans the space between its terminals. 2. Annealing furnace according to claim 1, characterized in that the end points of the bridge-shaped components (32, 33) by two mutually adjacent lower walls (22) of the furnace are supported. 3. Annealing furnace according to claim 1 or 2, characterized in that each bridge-shaped component (32, 33) consists of a lattice frame of a plurality of fluid-cooled tubes (34, 35, 36, 37, 38), which occupy a common, essentially vertical plane. 4. Annealing furnace with one of the supporting devices for the one to be heated Load existing frame, characterized in that at least some of the support devices have the shape of a lattice frame (32, 33), and each supported at its end points and made up of a plurality of fluid-cooled pipes (34, 35, 36, 37, 38), which occupy a common substantially vertical plane. 209836/0669 L / p 7260 -35- Dec. 7, 1971 B / We 5. Annealing furnace according to claim 4, characterized in that at least some of the support systems consist of bridge-like Components of fluid-cooled pipes (34, 35, 36, 37, 38), each bridge-shaped component has the space between the end points of the component bridged, and the end points of two mutually adjacent lower transverse walls (22) of the furnace are supported. 6. Annealing furnace according to one of claims 3-5, characterized in that in each lattice frame (32, 33) the flow λ medium-cooled tubes (34, 35, 36, 37, 38) are bent and a lower tube is at least one higher located pipe is supported at bends and between the end points. 7. Annealing furnace according to one of claims 4-6, characterized by intermediate tubes (36), which spiral-like upwards and downwards are bent below within the common plane and the uppermost tubes (34) with the lowermost tubes (35) of a lattice frame Connect (32, 33). 8. Annealing furnace according to one of the preceding claims, characterized in that at least some of the support systems grouped to form pairs of in the transverse direction f neighboring support devices are summarized, which are provided with jointly bent tubes (37, 38), which interconnections between the support devices of a Form pair (Figure 2). 9. Annealing furnace according to one of the preceding claims, characterized in that the end points of the support device (32, 209836/0669 L / p 7260 -36- Dec. 7th 71 B / We 33) are supported by movable carriages (31) which are provided with internal channels which a cooling liquid connection form between the tubes of the mutually adjacent support devices. 10. Annealing furnace according to claim 8 and 9, characterized in that a movable carriage (41) forms a common support for the two support devices of a pair. 11. Annealing furnace according to claim 9 or Io, characterized in that that, with the exception of the support device at the feed and discharge end (12, 13) of the furnace, support devices (32), which run mutually adjacent in the longitudinal direction through the furnace, a movable carriage (41) have, which supports at least two end points of different adjacent support devices (32). 12. Annealing furnace according to claim 9, 10 or 11, characterized in that each carriage (41) can be moved back and forth horizontally an opening (44) is arranged in the horizontal upper part of a lower intermediate wall (22) of the furnace, and the Dimensions are such that a carriage (41) forms a cover for the opening (44) regardless of its location. 13. Annealing furnace according to claim 12, characterized in that the carriages (41) are arranged on rollers (43), which in turn are arranged within the openings (44). 14. Annealing furnace according to one of the preceding claims, characterized in that it is a vibrating beam furnace due to the Drive devices for at least some of the support devices 209836/0669 L / p 7260 -37- Dec. 7th 71 B / We directions (32) is operable. 15. Annealing furnace according to one of the preceding claims, which works as a vibrating beam hearth, characterized in that that at least one pair of support devices (131 and 141, Figure 12) adjacent one another can be driven in this way is that the support device (141) of the pair, which is closer to the discharge end of the furnace, one Performs forward movement stroke when it is raised to support the load (20), and during a Movement phase in which the previous forward moving support device (131) in the direction of movement is lowered, no load (20) is supported measured in the direction of movement of the load through the 0 fen. Eat. Annealing furnace, in particular heating furnace according to one of the preceding Claims, characterized by the combination of (A) at least one smoke exhaust duct (73) in the full heat zones (18, 19) of the furnace near the discharge opening (13) for collecting exhaust gases in connection with means for generating of negative pressure within the smoke exhaust duct (73) with (B) burners (72), which are mounted so that they are in fire in the direction of movement of the load, and thereby remove the exhaust gases by suction and at the same time prevent them, that cold air entering the furnace through the discharge opening (13) from further penetration into the Oven (Figure 6) is prevented. 17. Annealing furnace according to claim 16, characterized in that the smoke extraction duct or ducts (73) are directed downwards from the discharge opening (13) . 209836/0669 3? Blank page