DE102008017729A1 - Plant for heat treating sheet glass/other panel-like materials, comprises a roller hearth furnace, a cooling station, a loading station in the form of receiving roller table, and an unloading station in the form of removing roller table - Google Patents

Abstract

The plant comprises a roller hearth furnace (1), a cooling station (2), a loading station (3) in the form of a receiving roller table, and an unloading station (4) in the form of a removing roller table. The furnace is implemented loadably with a combined inlet/outlet furnace door (5) on one side. The cooling station is implemented as heat exchanger, which comprises two roller paths independent from each other for a glass charge. The loading and unloading stations are arranged in the flow path on the side of the heat exchanger turned away from the furnace. The plant comprises a roller hearth furnace (1), a cooling station (2), a loading station (3) in the form of a receiving roller table, and an unloading station (4) in the form of a removing roller table. The furnace is implemented loadably with a combined inlet/outlet furnace door (5) on one side. The cooling station is implemented as heat exchanger, which comprises two roller paths independent from each other for a glass charge. The loading and unloading stations are arranged in the flow path on the side of the heat exchanger turned away from the furnace. A new, entering glass charge and a heat treated, exiting glass charge on the path of the furnace are present in the heat exchanger during a heat exchange phase. A heat transition takes place from the entering glass charge to the exiting glass charge. A pre-load station is arranged between the furnace and the heat exchanger and is implemented as flow station. A post-cooling station is arranged in the flow path between the heat exchanger and the unloading station and in which the entering glass charge is cooled on a handling temperature. The heat exchanger is provided with an air circulation device. The transport devices in the heat exchanger are separated from each other using air flow technology. The air circulation devices lead the air flow transverse to the flow direction at the glass charge. The duration of the heat exchange phase in the heat exchanger coincides with the period of the glass charge in the furnace. The transport device is arranged one above the other or next to each other in the heat exchanger. The heat exchanger or the transport device and the furnace are vertically or horizontally displaceable. The pre-load station is stationarily arranged in the flow path of the glass charge aligned with the unloading station. A second heat exchanger is arranged between the heat exchanger and the unloading station and/or the post-cooling station. At a product final temperature, the glass charge in the furnace is 600-650[deg] C, the temperature absorption of the exiting glass charge is 150-180[deg] C in the first heat exchanger and 100-150[deg] C in the second heat exchanger, and the temperature increase of the entering glass charge is 230-330[deg] C. The air temperature in the heat exchanger is constant on an average value above the final temperature of the entering glass charge and below the final temperature of the exiting glass charge. Each heat exchanger is provided with the air circulation devices such that the energy released during slowing down of the air circulation device is used for propelling the other air circulation device. The heat exchanger comprises a raisable cap on the upper side and/or tiltable valve on the lower side for disposing break glass, a laterally bent partition below the upper transport device and a laterally bent running base wall underneath the lower transport device for collecting and disposing break glass. Independent claims are included for: (1) a furnace for a plant for heat treating sheet glass or other panel-like materials; and (2) heat exchanger for a plant for heat treating sheet glass or other panel-like materials.

Description

The The invention relates to a plant for the heat treatment of Flat glass or other plate-shaped materials with the features of the preamble of claim 1, a furnace for Such a system according to the preamble of claim 25 and a heat exchanger for such a system according to the preamble of claim 27.

Around made of normal flat glass, for example tempered safety glass to let arise, one must memorize the glass plate a state of tension, in which the glass surfaces under compressive stress and the Inside of the glass plate is under tension. By this strong internal stress state breaks such a glass plate when exceeded a limit load in the smallest particles.

Of the desired state of stress of the glass plate is by heating the glass plate and then quenching, for example achieved by blowing with cold air. Quenching thus sets a uniformly heated to a high temperature Glass plate ahead.

The present method relates to the operation of a plant for heat treatment of flat glass in an oven, in particular and typically one Roller hearth furnace in which the glass plate or a group of glass plates one batch to the high temperature (the final product temperature) is heated, starting from then the subsequent Further processing, such as quenching, can be done.

at The teaching of the invention is therefore initially about the heating of flat glass in batch operation from ambient temperature (for example approx. 20 ° C) to the desired temperature (the final product temperature) the flat glass of several hundred ° C, in particular of about 650 ° C. This should be done in as short a time as possible.

The The teaching of the present invention is primarily to the heat treatment of flat glass, ie plate-shaped glass, directed. Basically technically similar problems but also in others with high Temperatures of a heat treatment to be subjected plate-shaped materials to observe. In principle, the doctrine can be The present invention therefore also to methods for heat treatment from other plate-shaped materials where similar Assignments exist, transfer. The terms "flat glass" and "glass batch" are intended So flat glass in the strict sense and other plate-shaped Materials containing similar problems of Heat treatment. "Flat glass" in the The sense of the teaching is therefore also curved or otherwise in three-dimensional Shape brought glass.

Regarding the terms "air", "chamber air" etc. It should be noted that in the present invention in general Any gas or gas mixture can be used. In particular, can the plant works with inert gas instead of air in the narrower sense, So provided in the chamber of the furnace, a protective gas atmosphere be.

Of the Term "furnace" in the context of the present Invention everyone for the heat treatment of flat glass or other plate-shaped materials suitable oven. In particular, it is in this respect a roller hearth furnace, at the glass batch to be treated on a "roller conveyor" as Transport device is located. But there are also other furnace arrangements, in accordance with the teachings of the present invention can be used.

Regarding the term "roller conveyor" is to be noted that it is a transport device on the The glass batch is located at the respective location of the system. Normally, a roller conveyor will be provided with ceramic rollers. It should be noted that it is because of the high Temperature usually act around rollers made of ceramic material but that in principle for the roles all Materials that can be used at the final product temperature in the work properly in each section of the system. A "roller conveyor" as a transport device suits a roller hearth furnace. For other furnace types are others Provide transport facilities, such as net-like transport facilities or transport facilities, which simultaneously represent bending tools for glass to be formed.

Of the Term "glass batch" means in the context of teaching the present invention a complete "filling" of Roller kiln, the corresponding complete "filling" of the corresponding to other stations of the plant. That can be one single large glass plate or a group of several smaller ones Be glass plates. For the teaching of the invention it is expedient also a glass batch from a group of glass plates as possible to realize completely in the roller furnace and in the other stations of the plant as full as possible To achieve the arrangement of the glass (typically achieved in several glass plates fill levels from 50% to 80%). The same applies to other plate-shaped materials.

Extensive designs for a plant for the heat treatment of flat glass with a continuous furnace are in the starting point for the teaching forming DE 10 2005 047 434 A1 ,

In the known plant for the heat treatment of flat glass, as in all other previously known systems (for example US-A-4,390,359 ), the flat glass of the incoming glass batch in the oven from ambient temperature, ie about 20 ° C, heated to a temperature above the transformation temperature, ie to a temperature of 600 to 650 ° C. Standard float glass has z. B. a transformation temperature of about 540 ° C and z. B. heated to a final product temperature of about 615 ° C.

The heated glass batch is then pre-stressed in a tempering and cooling station by building up internal stresses. Such is for example from the US-A-4,617,043 known. In the tempering and cooling station, the chamber has about the same inner length as the heat chamber of the roller hearth furnace, the glass batch is first blown with high air flow rate by means of one and the same fan assembly in the initial phase to the quenching with a temperature drop of about 100 ° C below to reach the transformation temperature. Between the interior of the glass and the surface while the required for the bias large temperature differences are present, and since the Wärmedeh voltage greatly changed when passing through the transformation temperature, so creates the desired bias in the glass plate or the glass plates of the glass batch.

To Quenching is slower cooling of the glass batch, by the blower arrangement with lower air flow capacity is driven. During the reciprocation of the glass batch on the roller conveyor in the tempering and cooling station, of the so-called "commuting", is the glass batch cooled down to a handling temperature of about 70 ° C. Then the glass batch from the tempering and cooling station demanded on the unloading station and unloaded there.

Instead of a combined tempering and cooling station is also a pure biasing station operating in the course known to the followed by a separate cooling station.

all aforementioned plants for the heat treatment of flat glass is common that they are very high energy consumption to have. One must first with a lot of energy, So huge electricity costs, the glass batch to a temperature heat above the transformation temperature. Subsequently One must just this glass batch by means of a huge Blower performance and thereby high electricity costs cool again to the handling temperature.

Of the Invention is based on the problem, a plant for heat treatment of flat glass, which are more favorable in terms of energy consumption works as a known plant for the heat treatment of flat glass, even with additional consideration Investment costs.

The previously indicated problem is in a plant for heat treatment of flat glass having the features of the preamble of claim 1 solved by the features of the characterizing part of claim 1.

According to the invention first of all the kiln can be loaded on one side, therefore does not have an inlet oven door at one end and at the other end a spout oven door, but a Combined inlet / outlet oven door on one side. Already With this measure, a significant energy saving reached. The heat losses of the furnace are reduced by about 30%, especially because it lacks the "passage", in an oven with separate inlet and outlet unavoidable is when a glass batch expires from the oven and simultaneously a new glass batch in the oven tapers.

One one-sided feedable oven, in particular roller hearth oven, has one lower throughput than an oven with separate inlet and outlet, because the change times of glass racks can be loaded on one side Oven are larger than the oven with separate Inlet and outlet. One can, if you like, encounter with a second oven in the plant.

The in the running Glascharge available amount of heat is inventively in the cooling station used to heat up a new, incoming glass batch. To According to the invention, the cooling station designed as a heat exchanger. Two from each other independent transport equipment, in particular roller conveyors, one for the heat-treated, expiring glass batch, the other for the new, incoming Glascharge, are in the heat exchanger, so that a heat transfer from the running glass batch on the incoming glass batch takes place.

The The result is a significant reduction in the heating time in the oven. The new, incoming glass batch already has a temperature of several hundred ° C, for example of more than 300 ° C, when she enters the oven. During the heating time for example, about 200 s, so the heating phase, are located two more glass bins in the heat exchanger. In this i. w. just as long heat exchange phase is realized according to the invention Heat transfer through which the expiring glass batch cooled and the incoming Glascharge is heated.

The possible with the system according to the invention Gradual heating of the glass batch reduces the risk of Bowl formation, in which the starting point for The teaching forming prior art as a significant problem has been called.

The Design of a plant according to the invention for heat treatment of flat glass or other plate-shaped materials depends largely on the thickness of the treated Glass batch off. For thicker glass rims, the desired, above explained bias directly in the heat exchanger. These are glass thicknesses of about 8 mm to about 20 mm.

at smaller glass thicknesses suffice the cooling capacity of the heat exchanger do not look to between the glass surface and the interior the glass plate to achieve a sufficient temperature difference. Here, a modification of the invention is recommended Plant through a classic tempering station between the furnace and the heat exchanger, designed as a flow station is. Such a biasing station provides the rapid temperature reduction for the purpose of biasing, so the temperature drop of example about 100 ° C. This leaves the leader station, running glass batch still a temperature of several hundred ° C, for example, more than 500 ° C. With a tempering station you can use the plant for heat treatment of flat glass or other plate-shaped materials for all thicknesses use. Without a tempering station you are on the treatment thicker glass plates, ie with thicknesses of approx. 8 mm and more, limited. Whether you use a tempering station or not So has application-related reasons, which against the additional Capital expenditure must be weighed.

One Heat exchange between the heat-treated, has expired glass batch and the new, tapered glass batch only up to a certain temperature difference thermally Sense. Accordingly, it is recommended that the last cooling step not in the heat exchanger, but in a post-cooling station, between the heat exchanger and the unloading station is arranged. In such a aftercooling station can you then the expiring glass batch conventionally (with ambient air) from about 200 ° C to a reasonable handling temperature from, for example, 70 ° C.

Around the necessary air circulation in the heat exchanger To achieve it is necessary that the heat exchanger is provided with an air circulation device, for example with appropriately designed fans.

Further preferred embodiments and developments of the invention Appendix are the subject of the further subclaims. These first deal with the arrangement and training the transport facilities, especially the roller conveyors, in the heat exchanger. In particular, it is recommended that the Transport devices in the heat exchanger on top of each other are arranged.

Here There are two competing interpretations. For one thing Provide that the incoming glass batch in the heat exchanger is arranged on the upper transport device. Then you have a natural heat convection from the hot, running glass batch to the still cool, tapered Glass batch. But to a defined heat transfer it is expedient to provide the transport device in the heat exchanger initially air flow technology separate from each other, so a direct heat convention not to provide at all. Rather, the air flow through directed the air circulation device. Then it may be more convenient be, the outgoing glass batch in the heat exchanger on the to run upper transport device. Especially with vertical movable transport device can be so optimize the organization of the movements of the glass rims in the plant.

Technically arrangement is a horizontal mobility of the heat exchanger or its transport facilities.

It may recommend as an alternative, the heat exchanger to keep stationary and to make the oven movable overall. This saves space and thus justifies the additional if necessary Investment. If a pretensioning station is provided, this is in this Case the pretensioning station as the heat exchanger stationary arranged, since they only in the passage way of the expiring glass batch is needed.

In The further subclaims are the temperature conditions differently designed and constructed plants exemplified.

Optimal is the design of the system according to the invention in the region of the heat exchanger when the air circulation device is designed so that the air temperature in the heat exchanger is substantially constant at an average slightly above the final temperature of the incoming glass batch and slightly below the final temperature of the expiring glass batch. Of course, in the beginning, this will be very asymmetric, the mean being widely spaced from the two actual temperatures of the glass bins. During the heat exchange phase, the final temperatures of the two glasses approach each other poke at this mean.

The inventive system can be further optimized by be that the heat exchanger two stages or even multi-level executes. Then the total heat transfer from the expiring glass margins on the incoming glass rims on both or all heat exchangers split. Achieved with it on the one hand, an increase in the throughput of the plant. On the other hand, the energy required for cooling The expiring glass batch significantly reduced, as you the fan power can reduce the air circulation facilities, because you have the Cooling time through two heat exchangers practically doubled. That's because the power consumption a fan with the air velocity in about square rises or, as here, decreases.

exemplary Data for temperatures at different interpretations Systems with two heat exchangers are the subject of another Dependent claims.

From Meaning is an indirect way to save energy, by accumulating at a Luftumwälzeinrichtung Transfer braking energy to another air circulation device can. For larger glass thicknesses must Performance of the air circulation device at the entry of the heat-treated Glass batch throttled into the heat exchanger at short notice become. Are several air circulation devices of several heat exchangers There may be a mutual exchange of energy here.

All in all allows the system of the invention a reduction the heating times almost like a two-chamber system. The danger the bowl formation of the flat glass is similar low as in a two-chamber system.

Of the Energy consumption of the entire invention Plant is much smaller than traditional heat treatment equipment of flat glass.

at An optimally designed system works to save energy three Components together. On the one hand, this is the design of the furnace with only one combined inlet / outlet oven door. Second This is the use of one heat exchanger or two Heat exchangers in series. Third, this is the interpretation in such a way that the after-cooling in the aftercooling station can be done with a much lower fan speed.

Regarding the construction of the heat exchanger with horizontal mobility recommended there is a liftable hood on top, to the transport facilities to make accessible. The underside is recommended for everyone Transport device an openable flap, over the accumulating broken glass is disposed down and out can be.

In accordingly, a construction of the heat exchanger is recommended in vertical orientation with a laterally inclined partition below the upper transport device and a corresponding laterally inclined bottom wall below the lower transport device. The lateral slope can also be after each side be formed outside. Overall serve the partition and the bottom wall for catching and laterally disposing of broken glass. Side flaps make the corresponding areas accessible.

object The invention is not just a plant for heat treatment of flat glass in general, but also a special oven for Such a system with the features of claim 25 and claim if necessary 26th

In corresponding manner, the subject of the invention is also a heat exchanger for a plant for the heat treatment of flat glass with the features of claim 27 and optionally the features of claim 28th

in the The invention will now be described with reference to a merely exemplary embodiments illustrative drawing explained in more detail. At this Explanation will also provide other benefits and specifics of Invention described in detail. In the drawing shows

1 a schematic representation of a system with a heat exchanger and without biasing station and the process there a) to e),

2 a 1 corresponding representation for a system with two heat exchangers and without pretensioning station,

3 a 1 corresponding representation for a system with a heat exchanger and with a biasing station,

4 a 1 corresponding representation with a movable furnace and a fixed heat exchanger,

5 a schematic representation of a horizontally oriented heat exchanger and

6 a schematic representation of a vertically oriented heat exchanger.

The Invention relates, as already detailed in the introduction explains a plant for heat treatment of Flat glass or for the heat treatment of other plate-shaped materials, For example, metal sheets o. The like .. Specifically deals the teaching of the invention with the heat treatment of flat glass. However, the transfer to other application fields can be made accordingly.

1 shows in the embodiment shown there, the system as a whole "in a plan view" and with the transport devices 6 in the heat exchanger 2 side by side. Accordingly, the transport facilities 6 from the respective glass batch 7 mostly covered and only the side of the glass batch 7 assumed area indicated. For reasons of a clear and simple presentation are the Transportein directions 6 only in 1a ). In all other illustrations, they should also be provided accordingly.

Corresponding representations can also be found for the plants according to 2 . 3 . 4 ,

1a ) first shows the schematic structure and the components of such a system.

Visible is first left oven 1 , which is designed for processing flat glass in particular and typically as a roller hearth furnace. Other furnace types can be used in a similar way.

Right next to the oven 1 there is a cooling station 2 in the oven 1 cooled to the right hot glass is cooled in a controlled manner. To the right of the cooling station 2 there is a loading station 3 , Is it the stove? 1 around a roller hearth furnace 1 That's the right design of the loading station 3 a task tray. On the far right outside there is an unloading station 4 , designed here in a preferred manner as Entladerollgang.

In 1a ) indicates that the furnace 1 one-sided feedable with a combined inlet / outlet oven door 5 is executed. Furthermore, it is indicated that the cooling station as a heat exchanger 2 is executed. For this purpose, the heat exchanger 2 at least two, in the illustrated embodiment exactly two independent transport means 6 for each one glass batch 7 on. According to a preferred teaching of the invention is in the transport device 6 , in adaptation to a roller hearth furnace as oven 1 to a roller conveyor. Such a roller conveyor is known from the cited in the introduction of the prior art. Such transport facilities 6 is also in the oven 1 and in the other stations 3 . 4 . 8th . 9 ,

Already in the introduction to the description of the definition of the term "glass batch" is explained may be referred to here.

Both the loading station 3 as well as the unloading station 4 is in the passage way on the stove 1 opposite side of the heat exchanger 2 arranged. A new, tapered glass batch 7 is on her way from right to left to the stove 1 during a heat exchange phase simultaneously with a heat treated, from left to right out of the oven 1 expiring glass batch 7 in the heat exchanger 2 , During this heat exchange phase, a heat transfer takes place from the glass batch running to the right 7 on the glass batch running to the left 7 ,

1 identifies the individual glass bins 7 based on the merely exemplary temperatures specified therein, which are realistic for a typical float glass.

1 shows a system with a heat exchanger 2 but without a tempering station. Such a system is, as has been explained in the introduction, primarily for thicker glasses, so glass bins 7 with a thickness of about 8 mm and more, especially suitable.

3 shows a corresponding attachment like 1 , but additionally with a separate tempering station 8th , The pretensioning station 8th is between the oven 1 and the heat exchanger 2 arranged and executed as a flow station. The only in 3 drawn pretensioning station 8th Performs in passing through the glass batch 7 that from the oven 1 with high temperature, a rapid drop in temperature for the purpose of preloading. It generates a temperature drop of, for example, about 100 ° C. However, this is done with continuous glass batch 7 , so that there is no room for a heat exchanger function here. A plant with a tempering station 8th is especially for glass bins 7 lesser thickness, ie, for example, from about 3 mm to about 7 mm, particularly suitable. For such thin glasses you get in a normal heat exchanger 2 the necessary temperature difference between the surface and the inside of the glass batch 7 not out.

In a system according to the invention there are in principle essentially two movement speeds of the transport devices 6 , First, there is a slow movement speed for the so-called "commuting" within the furnace 1 and the other stations. This speed of "commuting" is regularly at 0.01 m / s to 0.1 m / s. Second, there is the speed of movement of the glass batch 7 when changing from one station to another station. This "transfer speed" also applies to the passage through the pretensioning station 8th , It is usually 0.25 m / s to 0.5 m / s.

1a ) shows another special feature of the system shown in the form of a Nachkühlstation 9 between the heat exchanger 2 and the unloading station 4 , An expiring glass batch 7 persists, at least during the heat exchange phase in the aftercooling station 9 and is cooled therein from a residual temperature to a lower handling temperature, for example a temperature of about 70 ° C. For the reasons already explained in the general part of the description, a further heat exchange is no longer worthwhile at this low temperature level. Here is a classic air flow cooling of the glass batch 7 with ambient air.

In 1a ) is on the left a glass batch 7 in the oven 1 at the end of the heating period from approx. 60 s to approx. 400 s (depending on the glass thickness) and has reached a product final temperature of 615 ° C in the example case. So that glass batch 7 Now turn right into the heat exchanger 2 can run, is the heat exchanger 2 has been moved so that a transport device 6 for the reception of the glass batch 7 from the oven 1 free is. At the loading station 3 (Feed tray) is still a glass batch to be treated 7 with ambient temperature of 20 ° C. In the aftercooling station 9 is just from the transport facility 6 of the heat exchanger 2 running to the right a glass batch 7 arrived, which still has its starting temperature of about 320 ° C. In the unloading station 4 (Picking tray) is a finished glass batch 7 to handling temperature of about 70 ° C, which can be discharged accordingly here.

1b ) shows the transfer process of the product at the final temperature of about 615 ° C glass batch 7 from the oven 1 on the free transport device 6 of the heat exchanger 2 , During this transfer process, the cooling process in the post-cooling station 9 already started. There is the already pre-stressed glass batch 7 now cooled from the temperature of about 320C ° to the handling temperature of about 70 ° C.

In the transition from 1b ) on 1c ) is the heat exchanger 2 has been moved laterally.

In 1c ) is just the transfer process of preheated Glascharge 7 from the heat exchanger 2 with a temperature of about 300 ° C in the oven 1 and the new, tapered glass batch 7 from the loading station 3 in the just there becoming vacant transport device 6 of the heat exchanger 2 , Also during this transfer process, the cooling of the tempered glass batch 7 in the aftercooling station 9 further.

1d ) demonstrates the heating phase which coincides with the heat exchange phase. In the oven 1 becomes the glass batch in it 7 during the heating phase from about 300 ° C to about 615 ° C heated. At the same time in the heat exchanger 2 the heat exchange between the heat-treated, expiring glass batch 7 on the one transport device 6 and the new, tapered glass batch 7 on the other, adjacent transport facility 6 carried out.

In 1d ) is indicated the heating of the incoming glass batch 7 from about 20 ° C to about 300 ° C during the heat exchange phase and the corresponding cooling of the running glass batch 7 from about 615 ° C to about 320 ° C. In 1d ) can be seen further that during this phase, a new glass batch 7 on the loading station 3 is placed. Meanwhile, the glass batch is at the handling temperature 7 from the unloading station 4 taken. Furthermore, also the cooling of the glass batch goes 7 in the aftercooling station 9 further.

While the handover operations of 1b ) and 1c ) here last about 10 s, the duration depends on the heating / heat exchange phase according to 1d ) from the circumstances, in particular from the glass thickness. The period may be between about 60 s and about 400 s for uncoated glass, and for coated glass up to about 900 s.

At the end of the heating / heat exchange phase is another transfer process, the in 1e ) and again takes about 10 s. In this, the heat exchanger 2 first move slightly laterally and then cooled to about 320 ° C glass batch 7 from the heat exchanger 2 to the right into the aftercooling station 9 shifted, while at the same time the glass batch contained therein 7 , now cooled to handling temperature of about 70 ° C, in the unloading station 4 (ie on the removal gate) is moved. This will make this transport device 6 in the heat exchanger 2 free again. The heat exchanger 2 can now be moved laterally in another (transfer process of a few seconds, so that the position of 1a ) is achieved. At this time, the glass batch has 7 in the oven 1 reaches its final product temperature of approx. 615 ° C.

The system described above, with its design is optimal for glass bins 7 greater thickness, in particular a thickness of about 8 mm to about 20 mm. Compared to a conventional system with egg In a classic oven, the energy requirement is about 25% to 30% lower. The production capacity is about 20% higher, as the heating time in the oven 1 due to the preheating of the glass batch 7 in the heat exchanger 2 is correspondingly lower. The investment costs are similar to those of a conventional system without energy recovery.

In the 1 shown and in their course by means of 1a ) to 1e ) explained plant is for glass bins 7 less thickness, in particular a thickness of less than 8 mm, hardly usable, because the cooling in the heat exchanger 2 not going fast enough to get the necessary temperature difference for tempering the glass batch 7 to create. A modification of the operation of the heat exchanger 2 For example, by mixing cold ambient air, simultaneously affects the efficiency of the heat exchanger 2 and is therefore only a stopgap. For glass bins 7 lesser thickness, for example, a thickness of less than 8 mm, it is recommended to use a system according to 3 into which a tempering station 8th to the shock-like cooling of the glass batch 7 is integrated. This system will be explained later in detail.

As already stated in the general part of the description, it is recommended that the heat exchanger 2 with an air circulation device 10 is provided. Such is in the detailed representations before zugter heat exchanger 2 in 5 and 6 to find. These heat exchangers 2 will be explained later in more detail.

For a controlled and targeted heat exchange between the glass bins 7 in the heat exchanger 2 It is recommended that the transport facilities 6 in the heat exchanger 2 are separated by air flow technology and the air circulation device 10 the air flow in a certain direction, preferably transversely to the direction of passage at the glass rims 7 passes. This will be explained later in detail.

As previously explained in detail, the duration of the heat exchange phase in the heat exchanger 2 approximately equal to the residence time of a glass batch 7 in the oven 1 ,

The representation in 1 . 2 and 3 is chosen so that the heat exchanger 2 total horizontally across the direction of passage of the glass bins 7 is movable. This is one or the other transport device 6 in the heat exchanger 2 with the transport device 6 in the oven 1 aligned. 5 shows an embodiment of a thus constructed heat exchanger 2 , which will be explained in detail later.

4 showed one 1 corresponding representation of a system with a heat exchanger and without biasing station, in which, however, the heat exchanger 2 is fixed and remains stationary. The lateral relative movement is achieved here in that the furnace 1 total is transverse to the direction of passage horizontally movable. This is the transport device 6 in the oven 1 optionally with one or the other transport device 6 in the heat exchanger 2 aligned. The representation in 4 it can be seen that the space required for this system is less than in the embodiment according to 1 with the movable heat exchanger 2 , The increased effort with the procedures of the furnace 1 may be overcompensated under certain conditions by the smaller footprint of the so constructed plant.

The constructions are basically also with vertical mobility of the heat exchanger 2 , the transport facilities 6 in the heat exchanger 2 or the oven 1 realizable. 6 shows a variant of a heat exchanger 2 in which the transport facilities 6 vertically above each other.

Is with 4 the oven 1 opposite the stationary heat exchanger 2 movable, so it is recommended in the presence of a biasing station 8th in that the pretensioning station 8th like the heat exchanger 2 is arranged stationary, in the passage path of the expiring glass batch 7 aligned with the unloading station 4 ,

For the construction of a system according to 1 So with a heat exchanger 2 and without biasing station, it is recommended that at a final product temperature of the glass batch 7 in the oven 1 of several hundred ° C, in particular from 600 ° C to 650 ° C, the temperature recording of the expiring Glascharge 7 in the heat exchanger 2 more than 200 ° C, in particular about 250 ° C to 350 ° C, and the temperature increase of the incoming glass batch 7 in the heat exchanger 2 more than 200 ° C, in particular about 230 ° C to 330 ° C, is. Specifically, for the embodiment, the temperature decrease of the expiring glass batch 7 about 295 ° C, while the temperature increase of the incoming glass batch 7 is about 280 ° C. Interestingly, it is such that the air temperature in the heat exchanger 2 essentially constant at a mean value slightly above the final temperature of the incoming glass batch 7 and slightly below the final temperature of the expiring glass batch 7 lies. In the illustrated embodiment, the air temperature is in the heat exchanger 2 therefore at about 310 ° C.

At the in 3 illustrated embodiment of a system with a heat exchanger 2 and a stationary bias station 8th is the process according to 3a ) to 3e ) very similar to 1 , The toughening station 8th however, works as a flow station, which leaves the oven 1 draining and into the heat exchanger 2 incoming glass batch 7 shockingly cooled by a little more than 100 ° C. This system is especially for thin glasses, so glass rims 7 with a thickness of about 3 mm to about 8 mm particularly suitable.

In the illustrated embodiment, it is provided that at a product end temperature of the glass batch 7 in the oven 1 of several hundred ° C, in particular from 600 ° C to 650 ° C, the temperature decrease of the outgoing Glascharge 7 in the heat exchanger 2 more than 100 ° C, in particular about 150 ° C to 250 ° C, and the temperature increase of the incoming glass batch 7 in the heat exchanger 2 is about the same. In detail, there is a shock-like cooling in the tempering station 8th from about 615 ° C to about 490 ° C. In the heat exchanger 7 results in a decrease in temperature of the expiring glass batch 7 from about 490 ° C to about 280 ° C, ie about 210 ° C, while the increase in temperature about 240 ° C, namely from 20 ° C to about 260 ° C, is. The mean air temperature in the heat exchanger 2 here is about 270 ° C.

While the in 3b ) and 3c ) run in each case in about 10 s, extends the heat exchange phase or the heating phase above the above indicated, dependent on the glass thickness period ( 3d )). Again, it runs in the aftercooling station 9 during the transfer processes according to 3b ) and 3c ) and the heating phase acc. 3d ) cooling the outgoing glass batch 7 to handling temperature.

In the 3 shown plant is particularly suitable for low glass thickness, but basically for all glass thicknesses. The energy saving is about 30% compared to a conventional system. The production output is about 15% higher, as the heating time in the oven 1 correspondingly lower than in a conventional system. Since this system is also designed and suitable for low glass thicknesses, the air circulation device must 10 in the heat exchanger 2 be built more sophisticated. Glass frames with a smaller glass thickness require a blowing perpendicular to the surface. An injection parallel to the surface of the glass batch 7 would thinner glasses on the transport device 6 move.

As has already been stated in the general part of the description, one can further improve the energy savings in the system according to the invention, but with higher investment costs, that between the heat exchanger 2 and the unloading station 4 or the aftercooling station 9 at least a second heat exchanger 11 is arranged, that during the heat exchange phase in the second heat exchanger 11 at the same time a tapered glass batch 7 and an expiring glass batch 7 and that the total heat transfer from the expiring glass bins 7 on the incoming glass rims 7 on both heat exchangers 2 . 11 is divided.

For the in 2 shown system with two heat exchangers and without biasing station is provided in the illustrated embodiment, that at a product end temperature of the glass batch 7 in the oven 1 of several hundred ° C, in particular from 600 ° C to 650 ° C, the temperature decrease of the outgoing Glascharge 7 in the first heat exchanger 2 about 180 ° C to 240 ° C, and in the second heat exchanger 11 is about 160 ° C to 220 ° C and the temperature increase of the respective incoming glass batch 7 is about the same.

The process at the in 2 shown plant is similar to the expiration at 1 illustrated plant. The displacement movements of the two heat exchangers 2 . 11 occur synchronously or substantially synchronously, so that the transfer processes according to 2 B ) and 2c ) such as 2e ) also run substantially synchronously. For the transfer processes acc. 2 B ) 2c ) and 2e ) are each about 10 s provided. Again, the longest phase is the heating / heat exchange phase.

Taking into account the comments on the embodiments according to 1 and 3 are the temperature data for the embodiment of 2 self-evident. The air temperature in the first heat exchanger 2 is on average about 410 ° C, the air temperature in the second heat exchanger 11 at about 210 ° C.

The arrows in 2d ) indicate how the glass bins 7 in the loading station 3 put on and in the unloading station 4 be removed.

In the 2 shown system is optimal for larger glass thicknesses from about 8 mm. Compared to a conventional system, the energy consumption is reduced by about 50% and at the same time the production capacity is increased by about 30%. Moreover, the comments on the system of the embodiment of 1 , Not shown is a variant of in 2 illustrated plant, in which a biasing station similar to the embodiment in 3 is provided. There then applies for the Vorspannstation about what, even at 3 has been explained.

For the two heat exchangers applies with biasing station that at a final product temperature of the glass batch 7 in the oven 1 of several hundred ° C, especially from 600 ° C to 650 ° C, the tempera Acceptance of the expiring glass batch in the first heat exchanger 2 about 150 ° C to 180 ° C, and in the second heat exchanger 1 is about 100 ° C to 150 ° C and the temperature increase of the respective incoming glass batch 7 is about the same.

For systems with two heat exchangers 2 . 11 the total energy consumption for the cooling process is significantly reduced by the fact that the cooling capacity per heat exchanger halved and the cooling time is doubled. Due to the nonlinear dependence of the power consumption of the air circulation 10 the heat exchanger 2 . 11 This results in disproportionate energy savings.

As has already been explained in the general part of the description, the cooling performance when entering a hot glass batch 7 in the heat exchanger 2 be throttled for a short time. Because two heat exchangers 2 . 11 are provided, it can be provided that the Luftumwälzeinrichtungen 10 the two heat exchangers 2 . 11 electrically-control technology and electrical-performance technology are connected to each other, so that when braking the air circulation device 10 of the first heat exchanger 2 released energy for accelerating or further driving the air circulation device 10 of the second heat exchanger 11 is usable.

In the 5 and 6 are now two examples of a "two-lane" heat exchanger 2 shown in detail below.

The in 5 illustrated heat exchanger 2 has two juxtaposed transport facilities 6 in the form of roller conveyors. This heat exchanger 2 is therefore intended and suitable for the horizontal design of the system. The roller conveyors are each powered by their own drive motors 12 driven. Indicated by arrows is in 5 the air flow through the indicated air circulation device 10 is produced. The air circulation device 10 has a fan 13 and a drive motor 14 for driving the fan 13 on. By appropriate baffles 15 is the Luftströ tion in the heat exchanger 2 so steered that they are here transversely to the direction of passage at the glass bins 7 passes. This has the application advantages described above.

Accessible is the heat exchanger 2 according to 5 in that it has a liftable hood on the upper side 16 having. By pointing upward arrows are indicated lifting spindles 17 with whose help the hood 16 can be lifted vertically.

5 is further characterized by a special construction, which serves the disposal of broken glass. For every transport device 6 is an openable, namely swing down here flap 18 intended. Is there a break on one of the transport facilities 6 , so you can dispose of the cullet in this way simple and convenient.

The in 5 illustrated heat exchanger 2 leads on the left transport 6 hot glass, so the expiring glass batch 7 and on the right hand transport 6 cool glass, so the incoming glass batch 7 ,

6 shows the basic principle of a heat exchanger 2 in which the two transport facilities 6 are arranged vertically above one another. Also here you will find the transport facilities 6 each with a drive motor 12 , Here is also the fan 13 indicated. However, the connection here via external lines 19 , In the upper level of the heat exchanger 2 is the expiring, hot glass batch 7 while in the lower section of the heat exchanger 2 the tapered, yet to be heated glass batch 7 located.

Im in 6 illustrated embodiment is the air circulation device 10 in the heat exchanger 2 more complex than per se known blow box with orthogonal flow of glass bins 7 executed.

With regard to the disposal of broken glass is provided here that the heat exchanger 2 below the upper transport device 6 a laterally inclined partition 20 and below the lower conveyor 6 a laterally inclined bottom wall 21 for collecting and disposing of broken glass. One sees by means of 6 in that left flaps are located on the left 22 the access to the broken glass, which is on the partition 20 or the bottom wall 21 slide down to the left, open.

4 and 5 each show embodiments of horizontally movable or vertically movable heat exchanger 2 which are not restrictive. Of course, there are many other possibilities for the design of these heat exchangers. The illustrated heat exchangers 2 are in the rest as stationary heat exchangers i. V. m. a movable oven 1 used.

Arrangementally, a horizontal arrangement of the parallel juxtaposed transport devices 6 of the heat exchanger 2 especially useful. Thin glasses in a glass batch 7 may be due to a parallel flow on the transport device 6 shifted laterally. For thin glasses one uses therefore rather the in 6 illustrated classical blowing by means of a blow box construction.

Constructive solutions of air circulation devices of 5 and 6 are mutually also in the other transport facilities 6 used.

QUOTES INCLUDE IN THE DESCRIPTION

This list The documents listed by the applicant have been automated generated and is solely for better information recorded by the reader. The list is not part of the German Patent or utility model application. The DPMA takes over no liability for any errors or omissions.

Cited patent literature

• DE 102005047434 A1 [0011]
• US 4390359A [0012]
• - US 4617043 A [0013]

Claims (28)

Plant for the heat treatment of flat glass or other plate-shaped materials with a furnace ( 1 ), in particular in the form of a roller hearth furnace, a cooling station ( 2 ), a loading station ( 3 ), preferably in the form of a take-up wheel, and an unloading station ( 4 ), preferably in the form of a take-off wheel, characterized in that the furnace ( 1 ) one-sided feedable with a combined inlet / outlet oven door ( 5 ) is carried out that the cooling station as a heat exchanger ( 2 ) is carried out that the heat exchanger ( 2 ) at least two independent transport facilities ( 6 ), in particular roller conveyors, for each one glass batch ( 7 ) that both the loading station ( 3 ) as well as the unloading station ( 4 ) in the passageway on the furnace ( 1 ) facing away from the heat exchanger ( 2 ) are arranged and that a new, incoming glass batch ( 7 ) on the way to the stove ( 1 ) and a heat-treated, expiring glass batch ( 7 ) on the way from the stove ( 1 ) during a heat exchange phase simultaneously in the heat exchanger ( 2 ) and a heat transfer from the running glass batch ( 7 ) on the incoming glass batch ( 7 ) he follows. Plant according to claim 1, characterized in that between the furnace ( 1 ) and the heat exchanger ( 2 ) a biasing station ( 8th ) arranged and designed as a flow station. Plant according to claim 1 or 2, characterized in that in the passageway between the heat exchanger ( 2 ) and the unloading station ( 4 ) a post-cooling station ( 9 ), in which an outgoing glass batch ( 7 ) is maintained at least during the heat exchange phase and cooled to a handling temperature. Plant according to one of claims 1 to 3, characterized in that the heat exchanger ( 2 ) with an air circulation device ( 10 ) is provided. Installation according to claim 4, characterized in that the transport devices ( 6 ) in the heat exchanger ( 2 ) are separated from each other by air flow and the air circulation device ( 10 ) the air flow in a certain direction, preferably transversely to the direction of passage at the glass rims ( 7 ) passes. Installation according to one of claims 1 to 5, characterized in that the duration of the heat exchange phase in the heat exchanger ( 2 ) with the residence time of a glass batch ( 7 ) in the oven ( 2 ) is approximately the same. Installation according to one of claims 1 to 5, characterized in that the transport devices ( 6 ) in the heat exchanger ( 2 ) are arranged one above the other and that, preferably, the incoming glass batch ( 7 ) in the heat exchanger ( 2 ) on the upper transport device ( 6 ) is arranged. Installation according to one of claims 1 to 5, characterized in that the transport devices ( 6 ) in the heat exchanger ( 2 ) are arranged side by side. Plant according to one of claims 1 to 8, characterized in that the heat exchanger ( 2 ) or the transport facilities ( 6 ) in the heat exchanger ( 2 ) are moved transversely to the direction of passage, that optionally one or the other transport device ( 6 ) with the transport device ( 6 ) of the furnace ( 1 ) or the transport device ( 6 ) of the pretensioning station ( 8th ) is aligned. Plant according to claim 9, characterized in that the heat exchanger ( 2 ) or the transport facilities ( 6 ) in the heat exchanger ( 2 ) are vertically movable. Plant according to claim 9, characterized in that the heat exchanger ( 2 ) or the transport facilities ( 6 ) in the heat exchanger ( 2 ) are horizontally movable. Plant according to one of claims 1 to 8, characterized in that the furnace ( 1 ) is movable transversely to the direction of passage in such a way that the transport device ( 6 ) in the oven ( 1 ) optionally with one or the other transport device ( 6 ) of the heat exchanger ( 2 ) is aligned. Plant according to claim 12, characterized in that the furnace ( 1 ) is vertically or, preferably, horizontally movable. Plant according to claim 12 or 13, characterized in that the pretensioning station ( 8th ) like the heat exchanger ( 2 ) is arranged stationary, in the passage path of the running glass batch ( 7 ) aligned with the unloading station ( 4 ). Plant according to one of Claims 1 to 14, without prestressing station, characterized in that, at a final product temperature, the glass batch ( 7 ) in the oven ( 1 ) of several hundred ° C, in particular from 600 ° C to 650 ° C, the temperature of the outgoing Glascharge ( 7 ) in the heat exchanger ( 2 ) more than 200 ° C, in particular about 250 ° C to 350 ° C, and the temperature increase of the incoming glass batch ( 7 ) in the heat exchanger ( 2 ) more than 200 ° C, in particular about 230 ° C to 330 ° C, is. Plant according to claim 2 and optionally one of claims 3 to 14, characterized in that at a final product temperature of the glass batch ( 7 ) in the oven ( 1 ) of several hundred ° C, in particular from 600 ° C to 650 ° C, the temperature decrease of the outgoing Glascharge ( 7 ) in the heat exchanger ( 2 ) more than 100 ° C, in particular about 150 ° C to 250 ° C, and the temperature increase of the incoming glass batch ( 7 ) in the heat exchanger ( 2 ) is about the same. Plant according to one of claims 1 to 16, characterized in that the air temperature in the heat exchanger ( 2 ) is substantially constant at an average value slightly above the final temperature of the incoming glass batch ( 7 ) and slightly below the final temperature of the running glass batch ( 7 ) lies. Installation according to one of claims 1 to 17, characterized in that between the heat exchanger ( 2 ) and the unloading station ( 4 ) or the aftercooling station ( 9 ) at least one second heat exchanger ( 11 ) is arranged, that during the heat exchange phase in the second heat exchanger ( 11 ) at the same time an incoming glass batch ( 7 ) and an expiring glass batch ( 7 ) and that the total heat transfer from the expiring glass bins ( 7 ) on the incoming glass margins ( 7 ) on both heat exchangers ( 2 . 11 ) is divided. Plant according to claim 18, without prestressing station, characterized in that at a final product temperature of the glass batch ( 7 ) in the oven ( 1 ) of several hundred ° C, in particular from 600 ° C to 650 ° C, the temperature decrease of the outgoing Glascharge ( 7 ) in the first heat exchanger ( 2 ) about 180 ° C to 240 ° C, and in the second heat exchanger ( 11 ) is about 160 ° C to 220 ° C and the temperature increase of the respective incoming glass batch ( 7 ) is about the same. Plant according to claims 2 and 18, characterized in that at a final product temperature of the glass batch ( 7 ) in the oven ( 1 ) of several hundred ° C, in particular from 600 ° C to 650 ° C, the temperature decrease of the outgoing Glascharge in the first heat exchanger ( 2 ) about 150 ° C to 180 ° C, and in the second heat exchanger ( 1 ) is about 100 ° C to 150 ° C and the temperature increase of the respective incoming glass batch ( 7 ) is about the same. Plant according to one of claims 18 to 20, characterized in that the air temperature in the respective heat exchanger ( 2 ) is substantially constant at a mean value slightly above the final temperature of the respective incoming glass batch ( 7 ) and slightly below the final temperature of the respective running glass batch ( 7 ) lies. Plant according to one of claims 18 to 21, characterized in that each heat exchanger ( 2 ) with an air circulation device ( 10 ) and that the air circulation means ( 10 ) are connected to one another in terms of electrical control technology and electrical performance in such a way that when braking an air circulation device ( 10 ) released energy for driving the other air circulation device ( 10 ) is usable. Installation according to claims 5 and 8 and optionally one of the further claims, characterized in that the heat exchanger ( 2 ) on the upper side a liftable hood ( 16 ) and / or underside of each transport device ( 6 ) an openable, preferably swing down flap ( 18 ) for disposing of broken glass. Plant according to claims 5 and 7 and optionally one of the further claims, characterized in that the heat exchanger ( 2 ) below the upper transport device ( 6 ) a laterally inclined partition ( 20 ) and below the lower transport device ( 6 ) a laterally inclined bottom wall ( 21 ) for collecting and disposing of broken glass. Furnace for a plant for the heat treatment of flat glass or other plate-shaped materials, in particular roller hearth furnace, preferably for a plant according to one of claims 1 to 24, characterized in that the furnace ( 1 ) one-sided feedable with a combined inlet / outlet oven door ( 5 ) is executed. Oven according to claim 25, characterized in that the furnace ( 1 ) in total so transversely to the direction of movement of the glass batch in the oven ( 1 ), in particular vertically or horizontally, is movable, so that the transport device ( 6 ) in the oven ( 1 ) with different transport facilities ( 6 ) of an adjacent heat exchanger ( 2 ) is alignable. Heat exchanger for a plant for the heat treatment of flat glass or other plate-shaped materials, in particular for a plant according to one of claims 1 to 24, characterized in that the heat exchanger ( 2 ) at least two independent transport facilities ( 6 ), in particular roller conveyors, for each one glass batch ( 7 ) in such a way that at the same time two glass bins ( 7 ) in the heat exchanger ( 2 ) and a heat transfer from the one Gla batch ( 7 ) to the other glass batch ( 7 ). Heat exchanger according to claim 27, characterized by, the features of the characterizing part of one or more of claims 4, 5, 7-11, 23, 24.