JP2003525347A - How to heat treat metal press bolts - Google Patents

Abstract

Heat treating homogenized cooled cast metallic slugs or a rod section made of a lightweight metal alloy comprises: <??>(a) reheating the slugs /rod section for 20 minutes to a required temperature; and <??>(b) subjecting the slugs/rod section to a passive temperature compensation for a maximum of 3 minutes, leading to a temperature uniformity of less than plus or minus 10 K. <??>An Independent claim is also included for a device for heat treating homogenized cooled cast metallic slugs or a rod section made of a lightweight metal alloy comprising a heating device connected to a cooling device.

Description

Detailed Description of the Invention

The present invention relates to a method for heat-treating a bar piece when using a metal press bolt or a hot shear before it is brought into a extrusion press, and an apparatus for carrying out the method.

In the following of the specification, such bolts or rods are also referred to as blocks.

Blocks that have been cast, homogenized and subsequently cooled are subjected to a heat treatment immediately before they are brought into the press, during which they are reheated, subsequently cooled and then pressed into the press. Sent.

Such a method is disclosed, for example, in EP B1-0 302 623. In this case, the press block, which is cast in the usual way and which consists mainly of AlMgSi alloy, is first homogenized and cooled according to the state of the art after the casting process. Prior to pressing, the block is heated to a temperature above the melting temperature of the phases separated during cooling after homogenization and is kept at this temperature until the phases dissolve again. When reheated, the block is up to 20 minutes, 3
Above 50 ° C, after this reheating, the block is rapidly cooled to a pressing temperature below the melting temperature and up to 510 ° C. During this cooling, new separation of phases should be avoided.

In addition to what is almost impossible technically, in a production facility where a high loading is planned, waiting time and then keeping the temperature until all phases are dissolved again Limiting the time to less than 20 minutes causes dissolution of the separated phases,
This method is not suitable for use in heat treatment processes that occur prior to the actual extrusion step using high throughput extrusion.

In other words, it is possible to read from the specification of European Patent No. B1-0 302 62.
In the case of the method according to No. 3, the cooling process to reach the minimum cooling temperature takes up to 20 minutes. Therefore, a process with a course of a few minutes is important, in which the temperature is also due to heat conduction a relatively large distance, i.e. a further visibly large distance in the length direction of the block. Can be compensated. This is also the reason why in the above description only the respective temperature is explained.

However, such a moderately fast cooling is disadvantageous if a temperature profile, which is cooled in the pressing direction by cooling before pressing, a so-called temperature taper, is to be achieved in the block. This is because, even with relatively slow cooling, significant temperature compensation occurs along the length, which makes the production of the desired temperature taper difficult or impossible with controlled cooling. However, such temperature taper is
This is a prerequisite for an advantageous isothermal press.

The main purpose of the method disclosed in EP B1-0 302 623 is to increase the press speed and at the same time improve the quality of the extrudate. To support this advantage, examples are given in the aforementioned documents. In this case, the method according to the state of the art is compared with the method according to EP B1-0 302 623. With regard to the surface texture and with regard to the strength (Festigkeit) values, ie RPO 2, RM and swelling, the distribution of the technical measurements cannot be taken into account and no noticeable positive effect can be confirmed when using this method. This is not surprising, as experience has shown that extremely precise temperature control is very important, especially in the case of extrusion of light metal alloys with high productivity. However, with respect to this temperature regulation, the documents mentioned above do not mention what temperature accuracy is required or how this accuracy should be reached.

Further documents describe the heating of such blocks on the one hand and their cooling on the other hand.

In WO 83/02661 a device for heating press bolts and rods is disclosed. In this case, a burner or hot air jet generated by combustion is applied to the surface of the article. Exhaust gas is collected by an exhaust duct located above the heating area and supplied to the preheating zone by convective heat transfer. Convection heat transfer
It occurs by ejecting a heated article by means of a slit nozzle arranged aside, the gas flow being circulated by means of a ventilator in closed circulation towards the outlet of this slit nozzle. This device is only conditionally suitable for heating with narrow temperature tolerances at high loading rates. This is because the accuracy of the temperature that can be reached by direct application of the flame can be desired even with moderate charges. That is, the possibility of temperature regulation is that the exhaust gas collection duct does not depend on the accumulation of heat, so that the local production of exhaust gas in a particular area of this device always draws exhaust gas in the same way. Be adversely affected by. The disadvantage is also the convection heating, which, in principle, is more uniform than heating with direct flame application, occurs at the beginning of the device, where the material temperature is still low, so that high temperature Accuracy is not particularly important, but at the end of the heating process, where temperature differences can be tolerated only slightly, it is heated only by direct flame application, which is constrained by the method and Make the difference larger. That is,
The device according to WO 83/02661 is inconvenient in the sense of heating accuracy, ie it is constructed in the wrong order.

[0012] For example, in order to better utilize the hot exhaust gas of a heating zone with a direct flame actuation, a device is disclosed in German OS 26 37 646, in which case the exhaust gas is Before exiting the device through the exhaust pipe, hot exhaust gas is circulated in the convection heating zone, in front of the fast heating section with flame treatment in the article transport direction (Flammenbeauschschlagung), on the article using nozzle radiation. Spray on. The nozzle is a slit nozzle with the longitudinal axis of the nozzle opening extending perpendicular to the article axis located on either side of the article. This device also has the disadvantageous configuration of heating uniformity that there is a convection heating zone before the heating zone of the direct flame treatment.

A further apparatus using convection heating that does not directly flame treat the article is described in German O.
It is known from S 35 09 483 A1, German 34 18 603 C1 and German 195 38 364 C2. In these devices, the gas stream circulated in the convection zone for the purpose of convective heat transfer is heated by means of a heating device, from which heat is transferred onto the article.

All these devices have significant disadvantages. For devices using convection heating without direct flame treatment, it is possible to achieve uniform heating with a sufficiently uniform temperature distribution, but the operating temperature is the temperature that is most useful for a convection system equipped with a hot air ventilator. To limit the heat flow density that can be maximally transferred onto the article surface, and
Therefore, the heating rate is limited. As a result, during alloy exchange during production, which usually also requires changing the final temperature of the article, the relative charge rate (Durchsatzleistung) has the known disadvantage of relatively long article columns. Can be a small or long facility. This makes such a device in production operation inflexible and not suitable for performing methods requiring high precision. A further disadvantage is the relatively high cost and relatively high space requirements, limited by the relatively large length.

A device using heating by direct flame treatment is a light metal alloy heating device,
High furnace temperatures of about 1000 degrees allow very high heating rates, but the temperature distribution in the article is very non-uniform. In particular, when the surface of the article changes, the effect of strong radiation changes, so that satisfactory temperature uniformity cannot be reached even with costly control devices and techniques. If the production process suddenly stops, for example due to a press problem or a tool problem, the heated article often even begins to melt. Moreover, the energy utilization is low and therefore the thermal efficiency and energy requirements related to the loading of the articles are high.

These disadvantages also exist in the case of the device using convection preheating, which is known from German OS 26 37 646. Energy utilization is somewhat better, but is constrained by associating preheating with rapid heating, for example by direct flame treatment. When the flame treatment process works, only exhaust gas is produced, which is why
Temperature control becomes more difficult, and temperature accuracy in the article is poor, especially when production is interrupted, for example when changing tools. Therefore, for example, when the aluminum alloy AlMgSi is heated to a press temperature in the homogenization temperature range and is cooled near the melting temperature and subsequently at a high speed before extrusion to improve productivity and quality, the temperature is uniform. If special needs are made for sex,
It is not possible to use such a device A series of cooling devices are known for carrying out the cooling process. US Patent No. 5,
No. 027,634 discloses a cooling device consisting of at least one cooling ring, by means of which the block is pushed by means of a pressing device during the cooling process. The cooling provided by the cooling device over the length of the block is
It can be affected by variations in the pressing speed. The cooling ring itself comprises a large number of perforations with a relatively small diameter through which water used as cooling fluid is sprayed onto the block. The upper part of the cooling ring is open for the pressing device to pass through. Disadvantages in the case of this device are, among other things, the complicated control of the movement of the blocks and the costly transport mechanism, as well as, in particular, the small cooling nozzles that are prone to and the non-uniform cooling effect throughout, Is restricted by the opening because there is no cooling nozzle in the opening area above the cooling ring for the pressing device to pass through.

The device corresponding to US Pat. No. 5,425,386 attempts to avoid the disadvantage of small perforations in the cooling ring by means of a circle ring slit as nozzle opening. However, complex transport mechanisms and costly block motion control are still needed. Further, since the circle ring as the nozzle opening supplies the cooling fluid from the pre-combustion chamber, the same pressure can be used for the entire size of the nozzle slit. Therefore, there is no possibility to adapt the cooling to the block surface orientation requirements. The cooling process is determined by the vapor film in contact with the block surface, as the temperature of the block surface far exceeds the Leidenfrost temperature during a significant portion of the cooling process. When the block is horizontal, the cutting line extends perpendicular to the surface and the vapor film is different on the underside, the upside and both sides of the rod. Therefore, the step of applying water to achieve uniform cooling must also be able to be adapted to these different conditions.

The apparatus according to US Pat. No. 5,325,694 is used to facilitate handling of the apparatus and to automate the control by constructing a control system that couples the block temperature drop caused by cooling with the block feed rate. Will be tried. However, in this case, the additional required sensor not only costs more, but is also more prone to failure.

US Pat. No. 5,337,768 discloses a further embodiment of the control of such a device, which is similar in principle to US Pat. No. 5,325,694 mentioned above. Has disadvantages.

The present invention aims to create a method for heat-treating a metal press bolt or bar piece before carrying it into extrusion, and to create a device for carrying out the method, which does not exhibit the above-mentioned disadvantages. And In particular, a method and a device is presented which allows very precise heat treatment from reheating and cooling in temperature regulation while being very fast.

This is achieved by the characterizing part of the respective independent claim, and the intended variants of the method and the device are defined by the dependent claims forming a part of the present description.

In the case of extrusion, especially in the case of light metal alloys, in order to achieve high productivity, the entire extrudate is pressed at the highest possible speed, subject to specific and optimum extrusion temperatures. This is very important. To this end, it depends on the shape of the profile and on the tool, i.e. on the degree of deformation, and on the desired pressing speed as high as possible for productivity reasons, i.e. on the deformation efficiency,
Different initial temperatures of the blocks are required. Usually used for light metal alloys,
In the case of direct-acting extrusion, it is further important that at the beginning of the pressing process, the block has a temperature profile that drops towards the pressing direction, the so-called "temperature taper". Known for quite some time from the state of the art, this temperature taper is required to compensate for the increasing collection of mechanical energy from the beginning of the block to the end of the block, which energy is applied during the pressing process. Since it is converted into heat, the pressing process can still proceed isothermally. The more precisely this temperature taper is matched to the respective pressing conditions, the higher the pressing speed is selected and the greater the productivity.

According to the invention, the bolt or rod, ie the block, is first heated as quickly as possible to the highest possible pressing temperature depending on the respective material, after which the temperature in the block is It has a very small temperature tolerance and is evenly distributed. Usually, for example, in light metal alloys, the temperature tolerance is less than ± 10K,
For example, ± 5K for a block diameter of 250 mm to 300 mm.

After this heating, it is advantageous, especially in the case of high-volume extrusion operations, to cool the block in the fast cooling device with water as quickly as possible. As a result, after this fast cooling and temperature compensation, as a result of the block material-dependent heat transfer, blocks with the desired narrow tolerances for their respective press tools, and thus their respective profile morphologies, are for productivity reasons. It has a respective desired initial temperature on the tool-facing side of the block, which is optimum for the desired pressing speed as high as possible, and a respective optimum distribution of this temperature over the length of the block. Usually, for the fastest possible cooling, after about 30 seconds of effective cooling time, the time for temperature compensation, which is usually somewhat longer than the effective cooling time, mainly due to heat conduction occurring on the cross section of the block. Continues. After rapid cooling, the block is sent to extrusion and pressed. The transport time required for this is taken into account when determining the time for temperature compensation as a result of heat transfer.

The method according to the invention, contrary to the state of the art, uses the provision of blocks exactly with the respective required temperature or temperature distribution and this with the required slight temperature tolerances. It is possible to do it.

When pressing light metal alloys that are difficult to press, for example alloys with numbers 7xxx and 2xxx, this is usually done by indirect extrusion to eliminate the effect of friction on the receiving wall. Is used, and the advantage is that the block is
To have a certain higher temperature than the pressing temperature distributed as evenly as possible in the other blocks. Again, in addition to a uniform temperature distribution, it is also possible to obtain a local temperature difference over the length of the block, since, for example, relatively high temperatures can only be generated at the beginning of the block. Is easily possible using.

A further advantage of the method according to the invention is that it is suitable for pressing operations with a very high productivity. That is, if the cooling time and the temperature compensation are longer than the press continuation, the so-called block continuation time, the two cooling devices can operate in parallel, independent of the block continuation time of each block, and both The individual required cooling time and compensation time may be empirically known, even if the time fragments total longer than the block continuous time.

The unintentional interruption of the pressing operation, the consequence of which is the higher load, the higher the productivity of the extrusion, the method according to the invention being a decisive advantage over the state of the art. Have. That is, according to the present invention, during the first part of the heating process using convection heating, rapid heating is combined in the final part by direct flame treatment. In the case of this convection heating, the proper selection of the gas temperature makes it possible to eliminate the overheating of the respective material, even if the press is interrupted and consequently the transport of the block is stopped. As soon as the press is working again, a block with exactly the correct press temperature is available.

The main advantages according to the invention are that, according to the invention, according to the prior art known state of the art,
A rapid heating device with direct flame treatment is achieved by being combined with convection additional heating, where temperature compensation also occurs. This solution reduces the required cost somewhat because of the lower cost of a typical burner compared to a recuperative burner which can be used particularly advantageously. However, the main advantage of this simple solution is that this solution simply mounts at least one convection heating zone on the existing rapid heating equipment of direct flame treatment for the implementation of the method according to the invention.
It is suitable for additional equipment.

The main advantage with regard to production costs is that the consumption of gas is very low compared to the equipment according to the state of the art, which consumption is low for the preheating of the combustion air. This is achieved by the advantageous use of a burner with an integrated exhaust gas recuperator. Alongside this cost advantage, the use of a recuperative burner with integrated combustion air preheating is also controllable, as combustion air preheating and burner operation are clearly interconnected. Very advantageous. In the case of installations according to the state of the art, on the other hand, the exhaust gases of all burners are collected and taken off on one side, usually at the beginning of the flame treatment zone, to preheat the combustion air. Is supplied to the central heat exchanger. The central exhaust gas suction causes a longitudinal flow in the furnace which adversely affects the temperature control attitude of the individual zones. If, on removal of the block, the exit door of the heating device is opened, even cold air can enter the furnace in the continuous operation of exhaust gas suction,
This again adversely affects the temperature distribution and temperature control in the material column.
In the case of the method according to the invention and the heating device according to the invention, due to the operation of the recuperative burner with the exhaust gas duct, only when the respective burner is also actually switched on, finally the combustion gas in which the exhaust gas is produced is produced. It is achieved that the same or about the same amount is aspirated.

In addition to this advantage in control technology, there is an advantage in improving heat conduction. Recuperative burners are thus operated at very high flame outflow rates. This creates strong washing radiation around the block, further improving convective heat transfer without the use of special flow drives. In addition to this, the hot exhaust gas present in the heating device is also circulated along with the inductive effect of the high-impact burner radiation, which again improves the convective heat transfer.

Furthermore, in the case of the method according to the invention using a recuperative burner for heating, the recuperation is also such that under the correspondingly high furnace temperature, it works in a so-called phlox mode with flameless oxidation. May use a formula burner. Flameless oxidation means that the flame is invisible in the burner between the gas, the exhaust and the combustion air, such that there is some oxidation that gives off thermal energy in the burner radiation. This is a decisive advantage for equalizing the heat transfer on the block surface.

The recuperative burner described above is, in part, also suitable for phlox operation, as described in DE 34 22 221 4, EP 0 463 218 B1, EP 0 685 683 B1. And German Patent No. 195 41 922 C2
No.

Finally, the use of a recuperative burner according to the invention reduces the required installation length compared to installations of the same capacity corresponding to the state of the art. The reason for this is that the preheating zone, which is required in the case of installations corresponding to the state of the art, is omitted in order to reheat at least part of the exhaust gas heating. With greater capacity, this relatively short construction length not only means saving space, but also because the block pillars included in the equipment are shorter and simplify the operation of the equipment with different alloys, the process It is also advantageous in terms of engineering.

In summary, the method according to the invention has the following advantages, namely in terms of heating: The heating process is divided into high-speed heating by direct flame treatment only in the front part of the heating device and fast heating in which convective heat transfer takes place at the end of the heating device. Hereby, the high heating rate in the case of direct flame treatment is combined with the uniform heating without the risk of local overheating in the case of convection heating. 2. Possibility of retrofitting existing flame heating equipment for direct flame treatment by mounting at least one convection zone at the end of the existing heating equipment. 3. Use of an integrated recuperative burner with fresh air for preheating. This improves the control response of the heating device and also significantly reduces fuel consumption. Equipment length is reduced by omitting the preheating zone. 4. Possibility of using burners for operation with flameless oxidation, and thereby homogenization of heat transfer when directly applying burner radiation.

The cooling method according to the invention and the device for carrying out this method have further advantages. That is, instead of passing the block longitudinally through the cooling ring as in the state of the art, the front of the block is clamped and carried entirely into a fixed cooling device. Cooling is carried out using individual nozzles, which are precisely defined during the cooling process and which are associated with the block and which are arranged in a fixed annular shape. The desired cooling effect required to reach the required temperature or temperature distribution is achieved by the operation of this individual nozzle arranged in a ring with different presses and / or different start times. The cost of control and operation is essentially less than that of a device corresponding to the state of the art of the prior art, and moreover in terms of the temperature and the temperature distribution to be reached than with known devices and methods. Is also high.

The invention is explained in more detail below with the aid of examples in connection with the accompanying exemplary drawings.

The method according to the invention is illustrated by FIG. FIG. 1 schematically shows the temperature change of one block with respect to the time from the start of heating to the time of carrying into the press. First, the block operates directly in the example of FIG. 1 with a recuperative burner or a recuperative phlox burner for direct flame treatment, so that it is the highest in the area of the device where there is no preheating area for exhaust gas cooling. Receives high speed heating for 20 minutes. The heating is performed in at least one zone by a relatively low excess temperature (U
end with (ebertemperature). Here, temperature compensation occurs for up to 3 minutes. Then, it is carried into the cooling equipment. After an effective cooling time of up to 30 seconds, the block ends the temperature compensation time. During the final part of this compensation time, the block is brought into the press and then has a temperature difference between the end of the block and the start of the block in an isothermal press.

FIG. 2 diagrammatically shows how the individual coupling machines for carrying out the method according to the invention are arranged. The press is indicated schematically by the reference numbers 2 and 3. Reference numeral 2 designates a receiver, in which the block 1 is pressed and pressed by the press stamp 3 during the extrusion process. In the case of an extruded profile or a tool with multiple ejections, the profile (not shown) is directed to the outlet side 12 of the press. The block 1 is mounted on the presses 2, 3 using the block unloader 4 shown only schematically.

The heating is carried out in the feed direction 9, first by a direct flame treatment in the front of the heating device 7, and subsequently in two convective zones 8a and 8b which are illustratively connected back and forth, The last convection region 8b in the feed direction 9 is then operated at a low gas temperature. The blocks arrive from the heating device 7 to the transverse transport 5. The direction of movement is
It is indicated by the arrow 10. The block is conveyed from the transverse transport 5 into the cooling installation 6a or the cooling installation 6b, in which case it moves in the direction of the movement arrow 11a or 11b. As mentioned above, it is preferred to have multiple cooling installations if the installation operates at high productivity and short block continuous times.

The article 1 comprises pillars (in the figure simply indicated for reasons of simplification) made up of individual bolts or rods that have already been sucked in the longitudinal direction, on the conveying device, For example, as shown in FIG. 3, the device feeds a roller track. In the case of undriven rollers, they are conveyed out of the device via a stroke device. Another possibility, not shown, is that the articles 1 are conveyed through the apparatus by means of lifting rods or conveying chains. Driven rollers or other transport possibilities known from the state of the art can also be used.

The first part of the device mainly consists of the area of flame treatment. In FIG.
For example, two areas 7a, 7b for flame treatment are illustrated. In front of the zone 7 for the first flame treatment in the transport direction, there is an inlet area 13 and behind the zone 7b for the second (last) flame treatment, there is a separation zone 14. In the separation zone 14, two convection zones 8
The first convection zone 8a of a, 8b is connected and the last convection zone 8b in the transport direction mainly for temperature compensation forms the end of the device. In the areas 7a, 7b of flame treatment, the article 1 is heated by the flame produced using the burner nozzle 15. At that time, a large part of the heat is transmitted through the radiation from the surrounding furnace space to the article 1.
Be transmitted to. In the inlet section 13 and the separation section 14, the exhaust gas is collected in the burner and led out of the device from the exhaust gas duct 16.

Each of the convection zones 8a, 8b has a flow system, the flow system being at least 1
Two ventilators 17, at least one burner 22 for heating the hot air, and nozzles 18 arranged on both sides of the article for blowing and for convective heat transfer
including. The nozzle 18 is ejected from the ventilator 17 via a flow path system 19,
(See FIG. 3).

As is apparent from the flow chart corresponding to FIG. 4, the exhaust gas is guided through the heat converter 21 used to preheat the combustion air for the gas burner. In the convection sections 8a, 8b, the recuperative burner 2 for heating according to the purpose.
2, the exhaust gas cooled here by the preheating of the combustion air exits along the exhaust gas pipe of the burner.

A particularly advantageous embodiment of the flame treatment zone is shown schematically in FIG. The heating is performed with a reduced number of recuperative burners 22 compared to the flame treatment zone shown in FIG.
Done by. Therefore, in this embodiment, the external heat exchanger 21 for preheating the combustion air is omitted. Furthermore, the recuperative burner used was
When the corresponding furnace space temperature is reached, it is advantageously implemented as a fast burner and / or as a fast flox burner that automatically switches from the normal combustion mode to the flox mode.

As shown by the schematic flow arrow 23 in FIG. 5, the fast burner radiation utilizes the Coanda effect to impinge the article to be heated on a relatively large surface when the burner nozzle is advantageously formed. . The axis of the burner in the case of phlox operation, and thus the flame radiation 24 or the burner radiation, can also be tilted almost vertically to improve the flow impinging on the article surface. In order to improve the exposure of the burner radiation 24 to the article, it is also possible to influence it by the mouth of a nozzle made of a highly heat-resistant article such as silicon carbide. FIG. 6 is an advantageous example of such a possible high speed burner nozzle. FIG. 6a shows a burner nozzle, which transforms round burner radiation into flat radiation. FIG. 6b shows a burner nozzle in which the flat radiation has a passage in the center and both partial radiations are correspondingly stronger than in the case of FIG. 6a. FIG. 6c shows a burner nozzle with a “dog bone” -like jetting cross section, FIG.
d shows the cross section of the burner nozzle with the burner jets diverted from vertical. Figure 6e shows
Shown are a plurality (three in the figure) of burner nozzles performing individual jets, where the burner jets blow the article surface in different directions. In this way, 300 kW
With heat flow densities of / m 2, relatively large parts of the block surface can be reached.

A great advantage of the rapid heating device comes from the schematic temperature change of the central part and the surface of the article 1 shown in FIG. In the flame treatment zone where two zones F1 and F2 are envisaged in the example of FIG. 7, the furnace temperature is very high, as is the case with conventional flame treatment zones according to the state of the art. However, since these areas are now attached to the starting end of the device, there is no risk of overheating, and the extension of the article temperature curve for the various points of the article, shown schematically in FIG. In both convection zones K1 and K2 that follow, the temperature is not important as it can be compensated. In the second zone K2, the gas temperature (in-furnace temperature) is finally within the desired final article temperature range. This makes it impossible to overheat the article in the event of an unscheduled press stop and also in the case of interruption of the article transport in the device constrained thereby.

An advantageous embodiment of the cooling device for carrying out the cooling of the blocks corresponding to the heat treatment method according to the invention is explained with reference to FIGS.

The block 1 is surrounded by a group of individual nozzles 25, which are arranged annularly around the block in the lengthwise direction of the block 1 by means of a section 26 adapted for jetting of the nozzles. At that time, the nozzle 25 of the nozzle group is connected to the supply pipe 27.
Are connected to each other by. A cooling fluid is supplied to the supply pipe 27 from a supply pipe 28 of the nozzle group. Water is used as the cooling fluid, and this water is further purified, if necessary, such as demineralization. Between the main supply pipe 29 provided with a pump (not shown) and the nozzle group 28,
There is a fastener 30 and a pressure control valve 31 operated by the controller, which can be adjusted by the controller or manually. A water tank 32 is present in the lower part of the block 1, and a pump (not shown) uses a suction pipe 33 from the water tank.
The cooling fluid is fed back to the supply pipe 29 via the. Corresponding to the conventional state of the art, this circulation additionally incorporates a filter unit and a return cooler to carry away the heat taken from the block by the cooling fluid. If the aquarium can be installed at the lower part of the cooling device with a corresponding height difference, a downcomer pipe can also be used instead of the reverse feed pump.

For supplying to the injection nozzle 25, a pressure accumulator such as an elevated water tank may be used instead of the pump.

The block 1 is fixed on both end face sides by the clip holder 34, FIG.
reference. The clip holder 34 is similar to a screw fastener and is composed of a fixed portion 34a and a movable portion 34b, and the movable portion is pulled by the fixed portion by, for example, a cylinder 35. Hydraulic and hydraulic cylinders can be used. Further, the clip holder 34 is manufactured so that the nose 34 prevents the block from falling. A linear guide 36 is used to guide the movable portion 34b of the clip holder 34. This linear guide is fixedly connected to the guide rail 37 and can be pushed and moved by the guide roll 38 in the length direction of the block. This movement enables the loading and unloading of the blocks received with the clip holder from the loading and unloading position 39. This movement is also carried out using the cylinder 45 like the clip, hydraulically or hydraulically, or by another linear end force, for example by chain conduction, a spindle or a rack of gears.

The blocks are sent by the transverse process device 40 to the loading and unloading positions 39, which carry the block 1 into the open clip holder 34. The clip holder 34 can be used to sandwich blocks of different lengths. At that time, since the tool side of the block is always in contact with the fixed clip holder 34a, the classification between the temperature profile and the block is clear. In FIG. 9, the possibility of pinching blocks of different lengths is indicated by the dashed position 34b of the movable clip holder.

The injection area of the device is enclosed by a housing 41, which can be easily removed. The housing has a loading side and an unloading side.
For example, it has a door such as a lift door 42. It is advantageous to generate a negative pressure in the housing, for example by using a ventilator with corresponding dimensions, by directing the exhaust air from the housing to the outside, for example on the roof. This ensures that moisture and steam are prevented from reaching the cooling device installation space and thus the operating area of the press. The entire device is supported by a profile steel pedestal 43, which can be installed on a flat floor.

It is also possible to use holders as are known from block brush machine blocks, which are different from the block holders described.

The angle division 44 of the individual nozzle 25 is aligned with the jetting surface of the nozzle. Usually 4
An angle of 5 degrees is sufficient. This division angle allows the linear guide 36 to be constructed without problems, without compromising the nozzle ejection surface on the block surface.

The nozzle groups can be individually actuated using fasteners operated by the controller. The attached control valve 31 makes it possible to individually set a desired nozzle pressure for each nozzle group. The setting of the control valve 31 and the operation of the fastener 30 are performed using process control according to the purpose. In the cooling process, the block 1 must be entirely cooled and have a "temperature taper", for the cooling process,
First, all nozzle groups are switched on at the same time. After a sufficient time interval for the entire cooling process, the nozzle groups starting on the tool side of the block are switched off one after another, so the time of the entire cooling process is from the start end of the block (tool side) to the block end (press stamp side). Increase towards. The larger the time difference between the switch-off of the nozzle group at the start end and the end of the block, the larger the temperature difference over the length of the block, and the more obvious the “temperature taper”.

The clip holder 34 used for the block 1 and gripping on the end face of the block according to the invention ensures that the cooling fluid is applied to the block surface without being impaired by any foundation. The clip holder also protects the ends of the block, so that the heat flow in the block 1 flows almost radially at the ends, and the temperature distribution brought about by the cooling is not disturbed at the end faces by the end effect. To be affected. The heat transfer on a flat surface is above the Leidenfrost temperature in the range of film evaporation and depends mainly only on the density of the water hit, so that a cooling fluid, here water, above the stable Leidenfrost temperature is Uniform application ensures uniform cooling in the target area of the block surface temperature. Cooling effects with different orientations of the block columns (horizontal for cooling from above along the block surface, vertically on both sides, and horizontally from below along the underside of the block) ) Can be compensated in the use of the individual nozzles according to the invention by correspondingly selected, differently sized injection nozzles, preferably by the same type of injection nozzles.

FIG. 10 shows typical cooling curves for various measuring positions in one block. The locations of the measurement positions 1 to 12 are revealed in the diagram in the figure. The reference number written along the curve is associated with the temperature measurement number. After about 18 seconds of cooling time, and after about 60 seconds of compensation time following cooling time, the desired about 10K / 10
A "temperature taper" of 0 mm occurs and the temperature is also compensated up to about 20K across the block cross section. This temperature compensation elapses until the start of the press and lasts for the time of about 25 minutes required for block movement and positioning, so that the desired cooling and the desired "temperature taper" during the pressing process. Exists with sufficient and reproducible accuracy. The cooling provided by the cooling device according to the invention serves in particular for increasing the press speed and thus for the production quantity, so that a block duration of 60 seconds and shorter can be achieved. Thus, by operating a plurality of the described cooling devices in parallel, more time is available for the desired temperature compensation across the block cross-section despite the short block duration. This is important for such a short block duration.

If the cooling time varies over the block length, the cooling according to the invention in a fixed state takes advantage of the known physical properties of the temperature compensation process, which compensates the distance between points of the same temperature difference. Slowly, i.e. in the radial direction, essentially faster than the axial direction.

[Brief description of drawings]

FIG. 1 is a diagram showing a temperature fluctuation from the start of high-speed heating to the time when one block is brought into a press through high-speed cooling.

FIG. 2 is a diagram showing the configuration of an individual connecting machine for carrying out a heat treatment according to the invention.

FIG. 3 is a schematic view of an apparatus according to the invention for carrying out a fast superheat, including a cross-sectional view of the parts of the apparatus arranged in front and back, in direct flame treatment according to the state of the art. Heating is performed.

FIG. 4 is a flow chart of the schematically shown equipment in FIG. 3 for performing rapid heating.

FIG. 5 shows another embodiment according to the invention of the area of the flame treatment device which is direct by the use of a recuperative burner.

[Figure 6]   FIG. 6 is a diagram of an advantageous nozzle configuration for a fast recuperative burner.

FIG. 7 is a diagram representing typical temperature changes in individual parts of a heating device and in an article heated by the device.

[Figure 8]   FIG. 8 is a schematic sectional view of a high speed cooling device.

[Figure 9]   FIG. 9 is a schematic simplified side view of the high-speed cooling device.

FIG. 10 is a diagram including a typical cooling curve of the measurement points displayed in the diagram in the cooling end block.

[Procedure for Amendment] Submission for translation of Article 34 Amendment of Patent Cooperation Treaty

[Submission date] October 24, 2001 (2001.10.24)

[Procedure Amendment 1]

[Document name to be corrected] Drawing

[Correction target item name] Figure 9

[Correction method] Change

[Contents of correction]

[Figure 9]

─────────────────────────────────────────────────── ─── Continued front page    (81) Designated countries EP (AT, BE, CH, CY, DE, DK, ES, FI, FR, GB, GR, IE, I T, LU, MC, NL, PT, SE), OA (BF, BJ , CF, CG, CI, CM, GA, GN, GW, ML, MR, NE, SN, TD, TG), AP (GH, GM, K E, LS, MW, MZ, SD, SL, SZ, TZ, UG , ZW), EA (AM, AZ, BY, KG, KZ, MD, RU, TJ, TM), AE, AG, AL, AM, AT, AU, AZ, BA, BB, BG, BR, BY, BZ, C A, CH, CN, CR, CU, CZ, DK, DM, DZ , EE, ES, FI, GB, GD, GE, GH, GM, HR, HU, ID, IL, IN, IS, JP, KE, K G, KP, KR, KZ, LC, LK, LR, LS, LT , LU, LV, MA, MD, MG, MK, MN, MW, MX, MZ, NO, NZ, PL, PT, RO, RU, S D, SE, SG, SI, SK, SL, TJ, TM, TR , TT, TZ, UA, UG, US, UZ, VN, YU, ZA, ZW F-term (reference) 3K017 DC03                 4K034 AA01 AA18 BA03 BA08 CA03                       DA06 DB02 DB03 DB04 EA12                       FA01 FA05                 4K050 AA02 BA03 CA13 CD02                 4K063 AA05 BA03 CA06 DA14 DA28                       EA06

Claims (16)

[Claims] 1. When a cast, homogenized and subsequently cooled metal press bolt or a hot shear is used to heat treat a rod piece, preferably of a light metal alloy, immediately before it is brought into the press. A) the step of reheating the press bolt / the rod piece (1), and b) the step of cooling the reheated press bolt / the rod piece (1). D) the press bolt / bar piece (1) is reheated to the required temperature for a diameter of 200 mm for up to 20 minutes, and ) The reheated press bolt / bar piece (1) is subjected to passive temperature compensation for up to 3 minutes, f) for a diameter of 200 mm leading to a temperature uniformity of less than ± 10 K And the way. 2. A heat-treated metal press bolt, which is cast, homogenized and subsequently cooled, or, if used, a hot shear, for heat-treating a bar piece, preferably of a light metal alloy, just before it is brought into the press. A) the step of reheating the press bolt / the rod piece (1), and b) the step of cooling the reheated press bolt / the rod piece (1). And c) feeding the press machine, and d) the reheated press bolt / bar piece (1) has a diameter of 200 mm,
Undergoing rapid cooling using a water jet nozzle (25) such that a temperature of at least 150 K below the press temperature is produced on the surface of the press bolt / bar (1) within a nozzle jet time of up to 30 seconds, e ) A method, characterized in that the desired temperature distribution in the press bolt / bar (1) occurs over the cross section and in length after a temperature compensation time which is longer than the nozzle injection time. 3. The press bolt / bar piece (1) is heated to the most optimum temperature for the respective alloy and relative to this temperature, based on the requirements of the pressing process. At a very low pressing temperature, the heating is followed by the rapid cooling, in particular from the most optimal temperature for the respective alloy to the relatively low pressing temperature required for the pressing step. If a so-called temperature taper is produced when cooled, the press bolt / bar piece (
Press bolt / according to claim 1 or 2, characterized in that 1) is cooled to have the desired relatively low pressing temperature after an effective cooling time and the subsequent temperature compensation. A method for heat treating a rod (1). 4. A method for heat-treating a press bolt / rod (1), comprising heating in a first part (7) by a flame of a gas burner touching a surface and in a second part (8). The heating by forced convection using hot air nozzle spraying onto the surface of the article is performed, and the lower part (8b) at the end of the heating when viewed in the article transport direction is mainly used for temperature compensation in the article due to forced convection. , A method characterized in that it is operated at an upper temperature slightly lower than the final temperature. 5. A method for heat-treating a press bolt / bar piece (1), wherein the rapid cooling is performed immediately after the rapid heating step using individual water jet nozzles (25), the axis of which is fastened. Is directed radially with respect to a horizontal article axis, wherein the individual or groups of nozzles can be operated at different pressures and / or different switch-on times. 6. Deionized water is used as the cooling fluid,
The method according to any one of claims 1 to 5. 7. A cast and homogenized metal press bolt or, when using a hot shear, a device for heat-treating a rod piece, preferably made of a light metal alloy, immediately before it is carried into the press device. A) a heating device (7, 8), b) a cooling device, and c) the heating device includes a first portion (7) for heating by a flame of a gas burner touching the surface, and an article surface. A second portion (8) for performing heating by forced convection using a hot air nozzle jet blown onto the d), and d) when viewed in the article transport direction, the final lower region (8b) of heating is A device which is used for temperature compensation in an article and which is operated at a temperature slightly below the final temperature. 8. When using cast and homogenized metal press bolts or hot shears, a device for heat-treating a rod piece, preferably made of a light metal alloy, immediately before being brought into the press. A) a cooling device is used for fast cooling of the reheated press bolt / bar piece (1) with individual water jet nozzles (25), and b) individual water jet nozzles. The axis of is oriented radially with respect to the horizontal article axis,
Device, characterized in that the individual nozzles in group c) can be operated at different pressures and / or different switch-on times. 9. A cast and homogenized metal press bolt, or, if hot shear is used, a device for heat treating a rod piece, preferably of a light metal alloy, immediately before being brought into the press. A) the burner used is a recuperative burner, in which recuperators for preheating the combustion air are each individually integrated with the respective burner, An apparatus, comprising a thermal burner, b) burner radiation is expelled from a burner nozzle at high speed, in particular characterized in that at least some of the recuperative burners can be operated in a flock mode. 10. The nozzle of the recuperative burner (22) has a nozzle opening made of a highly heat-resistant material, which makes it possible to modify the cross section of the burner radiation (24), in particular: The nozzle of the recuperative burner (22) is connected to the burner radiation (24
) And / or the mouth of the nozzle divides the burner radiation (24) into at least two individual radiations, respectively. Equipment. 11. The press bolt or the rod piece (1) is in a fixed position in a high speed cooling device during a cooling process, the high speed cooling device comprising an annular arrangement of individual nozzles (25), In particular, the group of nozzles is formed by nozzles each arranged in an annular nozzle, and / or the nozzles have different sizes depending on the orientation of the bolt towards the jacket surface. , Claims 7 to 1
The apparatus according to any one of 0. 12. The bolt clamps an end surface of the bolt during the cooling step.
Fixed by a clip holder (34) that can be adjusted to different bolt lengths,
Device according to any one of claims 7 to 11, characterized in that, in particular, on the underside of the bolt, it has a nose (34c) for additionally fixing the bolt by means of the distal end of the instrument. . 13. Device according to claim 12, characterized in that for the clip device (34) a loading and unloading position is present in front of the cooling device. 14. The cooling times for the individual nozzle groups are different, and in particular:
8. The cooling time is followed by a time for the temperature compensation.
The device according to any one of claims 1 to 13. 15. The device according to claim 7, wherein at least two of said cooling devices are operated in parallel when the bolt continuous time is short. 16. The device according to claim 7, wherein a cooling fluid is supplied from a pressure accumulator to the nozzle of the high speed cooling device.