DE2356003C3 - Method and device for heating or annealing strand-like material - Google Patents

Description

The invention relates to a method for heating and / or annealing strand-like material, such as Wires, strands, ropes, rods, tapes or the like, hereinafter referred to as Wire referred to, preferably of aluminum wires, as described in the generic term of claim 1 and a device for performing the method.

The technology today is more and more using aluminum wires instead of the previous copper wires to use. When pulling such wires in a wire drawing machine stay in reinforced Dimensions of deposits on the wire back, which essentially consist of drawing agent residues and material abrasion (Tinsel) exist. Due to the particularly strong tendency of aluminum to oxidize, In addition, very resistant and high-resistance oxide layers are present. These deposits and Oxide layers are also characterized by uneven distribution over the wire surface the end.

In the conventional resistance annealing process, the wire is used for the purpose of transmitting electricity guided by contact rollers. This type of power supply is not possible with aluminum wire because it is the residues adhering to the wire deposit on the running surface of the contact discs and after a short time Prevent current transfer due to their insulating effect.

A previous cleaning of the wire (chemically, mechanically or the like) is ruled out because Due to the desired high working speed, the representation dur among other things is required Treatment times is not possible.

By taking appropriate measures, it is possible to keep these deposits continuously during operation To remove from the contact disk running surface, there is also the further disadvantage that due to the fluctuating contact resistance between the wire in the contact roll due to the impurities and oxide layers adhering to the wire surface, sparks form. Such spark formation damages the surface of the wire and, due to the erosion effect, material is removed from the surface the contact roller, which makes it unusable after an extremely short running time.

Attempts have therefore been made to resistively heat a wire, the electrical one To supply electricity with the help of electrolytes. With such a power supply no spark formation can occur appear. However, it turns out that in the prior art devices Power supply and thus the annealing temperature cannot be kept constant enough, which is the case with Glowing of aluminum wires especially because of the steep course of the temperature-expansion curve makes unpleasant noticeable; d. H. The smallest temperature fluctuations in the annealing zone lead to considerable Differences in the elongation at break of the wire. You therefore get different and uncontrollable ones Annealing results that show up, for example, as different strength, elongation and electrical Make the conductivity values of the wire noticeable.

In a known device, the wire is inserted from above into the electrolyte container and led out upwards again. The wire is deflected in each of the electrolyte containers instead of. With this device, the temperature cannot be sufficiently precisely at the desired limits be held, as caused by the deflection, the surface of the electrolyte fluids to form waves tends, as a result of which the length of the annealing path is changed in an uncontrollable manner. As a result fluctuations in the annealing temperature of the wire. Also, the liquid takes in the Containers, whereby the liquid level drops. As a result, the annealing path is lengthened, which is also noticeable in a change in temperature. Ultimately, however, it also finds its way through in the container the deflection of the wire requires no clean contact, which leads to fluctuations in the current transfer leads, which in turn affects the temperature in an uncontrollable manner.

The invention is based on the object of specifying a method in which the annealing temperature of the wire can be kept within narrow limits, so that aluminum wires in particular are annealed can.

This object is achieved according to the invention by the characterizing feature of claim 1. The fact that the wire at least in the annealing zone vertically or in an oblique direction from the first Contact container exits running upwards and running downwards into the second contact container occurs and an overflow is provided, a precisely defined one is in both containers towards the heating section Maintain fluid levels. This training therefore ensures an exactly constant annealing path length between the containers in contrast to the known devices mentioned.

The fact that the wire also runs through the electrolyte container without deflection does not exist either the risk of waves forming on the electrolyte surface. In addition, this measure creates a good contact between wire and electrolyte is achieved.

In the arrangement according to the invention, the electrolyte tends to counteract due to the force of gravity the direction of movement of the wire when it exits the first electrical container to run back into it, so that only a small amount of electrolyte adheres to the wire itself, which means that it heats up much less has the consequence.

In addition, it has been found that the electrolyte adhering to the wire has a very strong influence on the Keeping the annealing temperature constant. During the heating of the wire, the adhering Electrolyte will be evaporated. Apart from the fact that for this reason an increased heating power is required is. this fact leads to considerable fluctuations in the wire temperature; this in particular when the amount of electrolyte adhering to the wire is not constant. This in turn is always the case, because of vibrations of the wire, due to the different surface structure of the wire and the like, more, more or less electrolyte is entrained from the contact container.

The evaporation of the electrolyte also causes electrolyte residues to bake on the wire surface fixed, the in the second contact bath an uneven current transfer and thus uneven Have annealing temperatures result.

About the temperature fluctuations in the wire mentioned above and the resulting effects To avoid this, it is necessary to keep the liquid adhering to the wire on the cold wire as far as possible to be removed before entering the actual temperature phase, which is the second part of the annealing zone, got.

This is achieved according to the invention by the following measures, each for itself or but can also be used together:

1. It is behind the first contact bath of a heating section a scraper is provided.

2. A blow-off nozzle is provided behind the first contact bath of a heating section.

3. There is a pulley for the wire behind the first contact bath of a heating section a collecting device provided. Using the centrifugal effect, the Liquid adhering to the wire is thrown off as it passes over the pulley and caught by the gutter.

The collecting ring is arranged around the revolving rollers or designed in such a way that it throws the thrown off Liquid drains away at its lowest point via a reflux. In the passages of the Sleeves are inserted through the ring, which protrude into the inner groove of the collecting rings, so that the electrolyte accumulating in the groove does not run through the wire passage openings can, but only flows off through the return.

Throwing off the liquid with the help of centrifugal force is of general importance. Such a one Measure can be provided wherever liquid is to be removed from the wire, that is for example, also behind the second contact container or behind a subsequent flushing section and the like.

To easily insert the wire around the pulley, the catch ring can be split, for example be designed to be hinged.

The invention is also not intended to address the abovementioned options for removing the electrolyte be bound by the wire in terms of the order specified.

The vertical or inclined arrangement of the electrolyte container has the further advantage that it sags of the wire in the electrolyte container is avoided. This brings a number of advantages with himself. This in particular avoids chafing of the wire at the entry and exit points the electrolyte container can be open towards the annealing section, so that there is no friction here. Further > The uneven current transfer from the electrodes to the wire becomes uneven when the wire is sagging Wire, due to the different distance from the top and bottom of the wire to the electrodes, avoided. The electrodes can be circular

ι »have cross-section, and the wire runs in the Axis of each electrode. Finally, when compared to a sagging wire, the frictional resistance becomes of the wire in the electrolyte and finally a fluttering of the wire as it passes through

i "· avoided by the electrolyte container.

In addition, the vertical arrangement is chosen to avoid deposits of residues and other parts dissolved in the electrolyte in the contact container, and here primarily on the electrodes,

- <· to be excluded. Apart from the fact that when the contact container is soiled, a repeated Cleaning is required, such sludge deposits lead to uneven current transfer and thus to temperature changes in the wire. at

- '■> the horizontal belonging to the state of the art Arrangement of the container, the deposits collect in the lower part of the container and cover them • here the electrode. As a result, the current transfer from the electrode to the wire with increasing AbIa-

iii is getting worse and worse, and it arises over the Cross-section of the contact bath and thus of the wire an uneven current distribution.

With the vertical arrangement of the contact container according to the invention, these back-

j'i do not stand on the electrodes. you will be rather, continuously with the down through the einzw. Outlet opening outflowing electrolyte carried out of the container.

In order to also have such storage areas in the lower part of the container

- Restrictions are to be avoided in a further development of the invention, the lower outlet openings are conical.

Under the named aspects, the exact vertical arrangement of the containers and the wire

4 ". Tes the best possible solution. An inclined arrangement however, the container and the wire could be provided to prevent the electrolyte liquid constantly escaping from the lower container openings through which the wire is

, (I ability drips onto pulleys and the like and this brakes and sticks, which leads to a wire break, especially with extremely thin wires can.

According to the invention is between the electrolyte

> -, containers in the annealing section, as already stated, a pulley is provided. Such a wire deflection is generally rejected because of the Wire along the annealing path is particularly sensitive. However, it has been found that such an

Mi steering role then except for the reasons already mentioned It is even advantageous if it is arranged in such a way that the deflection in the first part of the annealing section, at best immediately after the first contact point, takes place and the roller is driven. In the

b => over the course of the annealing section, the wire is its starting temperature is heated to the maximum temperature, whereby it reaches the maximum temperature immediately before entering the second contact bath

achieved. A driven pulley in the first part of the annealing section therefore has no negative effects on the wire, as it is in this area, due to the low temperature present here, is still insensitive. But it has the advantage that the wire, resulting from the wrap-around friction on the reel, completely relieved, enters the critical second part of the annealing section, where the wire, due to the high temperature present here, only extremely low mechanical loads are applied can. That means all resistors acting on the wire in front of the annealing section, such as, for example Frictional resistance in the first contact bath is compensated for by this pulley. At the In the absence of a driven roller, these forces must pass through one behind the annealing section arranged take-off roller, a winding device or the like over the in the second part of the annealing line extremely sensitive wire can be applied. However, this has to stretch the wire Consequence with the resulting negative effects, such as loss of elongation, strength increases and the like.

This does not occur with the device according to the invention.

It can also be advantageous to drive the other pulleys of the device. Through this the resistances acting on the wire are gradually compensated and thus the Tensile stresses in the wire kept low, which in addition to the annealing zone in a special way also in the Already annealed wire is of the utmost importance to avoid stretching.

This drive of pulleys and the resulting relief of the wire is particularly important Low strength and great softness wires, such as aluminum wire, are of the utmost importance.

In addition, such roles, as already stated, can be used to the Throwing off any liquid adhering to the wire.

The electrolyte container and / or the deflection roller can be designed to be adjustable in height in order to achieve the To be able to adjust the length of the resistance path. This allows the device in a simple manner different materials, cross-sections of the annealing material and requirements regarding the annealing result, be adjusted.

In order to simplify the introduction of the wire into the container, a further embodiment of the invention provided to make this foldable. It has proven to be particularly useful to have two nested to provide mutually rotatable tubes around the container axis, which along a Surface line each have a slot. To insert the wire, the slots are turned over one another. After inserting the pipes, they are twisted against each other to ensure a seal.

Another step in promoting the solution of the object according to the invention consists in means and To take measures to ensure that the wire is always supplied with electrical power necessary to keep the temperature constant. So it is inevitable, for example, that the conductivity of the electrolyte during operation changed, due to impurities carried over by the wire and deposited in the electrolyte, through chemical processes (e.g. electrolysis), through changes in concentration (for example through evaporation and drag-out), through temperature changes in the electrolyte and the like.

These phenomena are the task of the invention, namely keeping the constant Power supply and thus the annealing temperature of the wire.

For the advantageous embodiment of the invention, the following additional measures are provided in this regard:

1. Cleaning the electrolyte to keep the conductivity constant.

2. Keeping the electrolyte temperature constant in order to keep the conductivity constant.

3. Continuous or at intervals measuring the conductivity of the electrolyte for the purpose of Initiation of countermeasures in the event of deviations from the target value.

4. Electrical current control to keep the current supply to the glowing wire constant when the conductivity of the electrolyte and / or the wire changes.

The measures according to points 1 and 2 can be advantageously implemented in the circulation circuit of the Include electrolytes.

The measures according to points 1 to 4 can be taken individually and / or in part and / or together be applied.

In addition to electrical current regulation, it can also be advantageous to have electrical voltage regulation provide for voltage fluctuations and temperature fluctuations resulting therefrom to compensate.

For the same purpose, an electrical power or temperature control can also be used for the glowing wire may be provided.

In a further embodiment of the invention it is provided to use an electrolyte that is equal to

i exerts a pickling effect on the wire and it Pickled bright, so to speak, which also has a positive effect on the current transfer. If you use one Alternating current, then one becomes according to the frequency of the alternating current and depending on the

, applied electrolyte notice a pulsating pickling and / or oxidizing on the wire. Using a direct current it can be achieved that the wire depending on the electrolyte and Polarity in the individual contact containers either

ι is pickled or anodic oxidation takes place.

In principle, different electrolytes can be used in the containers. Further can be provided, the strand-like material between

to let the containers run through a protective atmosphere in order to react with the ambient air impede.

Furthermore, it was found that when the hot wire enters the contact fluid in the

) a glow occurs near the electrolyte surface, which leads to extremely strong fluctuations in the power transmission to the wire and thus to temperature fluctuations leads in the wire.

Keeping the heating-up constant in this regard

i temperature is achieved at the point of entry of the hot wire in the electrolyte in a concentrated manner electrolyte is supplied, and end the electrode below the entry point

(Jet. This will prevent the appearance of the glow at this point.

It is particularly advantageous if the electrolyte fed in here has a significantly lower temperature has than the wire temperature at this point, and if a faster electrolyte throughput in this range is pictured.

This is achieved in the simplest possible way that the supply of the electrolyte in the contact containers takes place in the immediate vicinity of the point of entry of the hot wire. In a special embodiment is the actual contact container on the entry side of the hot wire an additional short electrolyte path upstream, which is led into the contact container. This additional electrolyte line can for example consist of a tube to which electrolyte is fed separately. For this Tube can be selected with a small cross-section in order to achieve the fastest possible flow of electrolyte to reach.

In a modified configuration or as a supplement, a correspondingly designed pressure spray nozzle can be used are provided, the exiting beam runs in the direction of the wire and in the second The contact bath of the annealing section ends. This nozzle can also be designed so that the intensity of the pressure jet and thus the throughput is adjustable.

In the same way, gaseous substances, for example compressed air or a reducing gas can be used.

The electrolyte supply to the actual contact container can take place independently; however, it can also the upper electrolyte overflow and / or the lower electrolyte outlet of the upstream cooling device can be used to feed the contact tank.

The electrolyte fed in here can have the same temperature as that of the actual contact bath supplied; however, it can also have a different temperature.

The above-described keeping the electrolyte temperature constant can also be provided to the To keep the quenching effect on the hot wire constant or to keep the temperature curve of the wire in To influence depending on the electrolyte temperature.

The measures described can also be used with electrolytes. which environmentally friendly are.

The device is advantageously used for heating or annealing strand-like material in connection with an upstream drawing machine, such as a wire drawing machine and a downstream extruder and / or winder.

Exemplary embodiments of the invention are shown in the drawing. It shows

Fig. 1 is a view of the device for annealing a wire, partially in section,

FIG. 2 shows a modified detail of FIG. 1,

Fig. 3 is a section along the line III-III of Fig. 1,

Fig. 4 is a section along the line IV-IV of Fig. 1,

FIG. 5 shows a modified detail of FIG. 1,

6 shows a modified detail of FIG. 1,

FIG. 7 shows a modified detail of FIG. 1.

The wire 1 emerging from a wire drawing machine, not shown, is passed through a pulley 2 is steered in the vertical direction and enters an electrolyte container 4 through an opening 3. He passes through this container 4 and is fed to a second electrolyte container 6 by a pulley 5. The wire emerges from the container 6 through a lower opening 7 and leaves the device via a roller 8. The rollers 2, 5 and 8 are driven to move the wire in particular along the annealing section between the containers 4 and 6 to relieve.

The electrolyte containers 4 and 6 are, as has not been shown in detail, adjustable in height. Likewise the roller 5 and also the rollers 2 and 8 can be height-adjustable to the length of the annealing section between bins 4 and 6. In each container, as shown for container 4, Electrodes 9 are provided, which are connected to a power source 10. The electrodes 9 can also form the electrolyte container at the same time.

An electrolyte is continuously supplied to the electrolyte container 4 via a connection 11. This occurs over the upper edge 12 of the container 4 and is caught in an overflow 13 to then to flow through a pipe 14 into a storage container. The draining electrolyte is again over the Pipe 11 is pumped into the container 4. Means can be provided in this circuit for cooling and / or cleaning and / or measuring or monitoring the properties of the electrolyte, such as concentration, Conductivity, pH and the like.

A corresponding arrangement has been made for the container 6.

Since it can hardly be avoided that 3 drops of electrolyte emerge through the opening, there is another Drain 15 provided.

Due to the overflows of the two containers, the length of the annealing path is precisely defined because the Electrolyte surfaces 12 are always aligned horizontally and can be regulated so that they are in their level does not fluctuate.

The containers 4 and 6 are circular in cross section, and the electrodes 9 surround the wire annular, d. H. this is always the same distance from the electrodes, so that a uniform current transfer takes place in the electrolyte containers 4 and 6 to the wire passing through.

According to FIG. 2, the wire 1 is guided through a container 24 which is arranged at an angle. The liquid emerging from the inlet opening 23 drips off in the direction of arrow 25 and can do not reach the roller 2 and this may stick or slow down. A corresponding arrangement can be provided for the second electrolyte container. The container 24 can in its other Training correspond to the container 4.

As can be seen from Fig. 3, the electrolyte containers consist of two mutually twisted Tubes 30 and 31, whereby the tube 31 can be designed as an electrode and the tubes 30 and 31 longitudinally ι a surface line each have a slot 32 and 33. Be used to insert the wire into the container the tubes twisted so far that the slots 32 and 33 are superimposed. After inserting the wire the tubes 30 and 31, for example, in the position of FIG. 3 twisted in the over the slots no Liquid can escape.

The electrolyte containers 4 and 6 taper off at their lower ends 33 and 34. Get in the electrolyte

Any sludge or the like located there is in this way with the electrolyte through the openings 3 and 7 carried out of the containers and cannot settle in them.

Above the electrolyte container 4, a scraper 35 is initially provided, which adheres to the wire Strips off electrolyte fluid. In addition, a blow-off nozzle 36 is provided behind the scraper 35, which can be formed, for example, according to FIG. 7, when air is pressed into the opening 37.

Remaining liquid particles are removed from the wire due to centrifugal force when it overflows the Deflection roller 5 thrown off. So that these liquid particles do not rewire the wire in the actual Annealing zone, d. H. meet above the electrolyte container 6, there is a collecting ring 38 around the roller 5 placed (see. Also Fig. 4). The liquid particles collect here in a channel 39 and run downwards and via a drain 40 back into the storage container. So that no liquid running down through the wire inlet and outlet openings 41 and

42 can escape, pipes are in these openings

43 and 44 arranged, which grip with their upper part through the ring 38, so that the running in the ring Liquid must pass the tubes 43 and 44.

To protect the wire in the annealing section from atomized electrolyte and / or to create a protective atmosphere in order to build up the wire, between the roller 5 and the container 6, for example, a tube 60 be arranged through which the wire runs.

Once the wire has passed the annealing section, it enters the electrolyte container 6. When entering The electrolyte shows a glow in the immediate vicinity of the wire in the liquid surface. It has been found that this lighting up strongly falsifies the current transfer.

In order to prevent the lighting up, according to FIG. 5, an additional pipe 51 opens into the electrolyte container 6, through which the wire 1 enters the container 6. In the pipe 51 is a valve 52 and a pipe connection 53 electrolyte is constantly pressed into the actual container 6. The tube 51 has a relatively small one Cross-section in order to obtain a high flow velocity of the electrolyte and thus a good cooling effect.

At 54 the electrolyte exits the container 6 again to be re-cooled and via the tube 53 in the container to be pumped.

Because of the small cross-section of the tube 51, there is sometimes insufficient electrolyte in the container 6 are fed.

According to FIG. 6, a further connection 55 is therefore provided, via which additional electrolyte into the container 6 is pumped.

Instead of the tube 51, a nozzle according to FIG. 7 can also be provided. In the axis of the nozzle will be the wire 1 is inserted into the container 6. An electrolyte can be pressed through the openings 37, which comes out with a violent jet from the nozzle opening 46! occurs and deep into the liquid arranged in the container 6 penetrates.

For this purpose 3 sheets of drawings

Claims (1)

Patent claims: 1. Process for heating and / or annealing strand-like material, such as wires, strands, Ropes, rods, bands or the like, preferably made of aluminum wires, in which the Wire is heated by resistance and the current is heated with the help of electrolytes arranged in containers is fed to the wire and in which the wire is in a vertical or approximately vertical direction or obliquely running upwards from the first contact container and after Deflection in a vertical or approximately vertical or inclined direction in the second Contact container occurs, characterized in that the wire without influencing how Deflection, through the electrolyte container in a vertical position or approximately vertical direction with the help of provided floor openings and deflecting the wire between the electrolyte containers with the aid of at least one Deflection roller takes place that electrolyte fluid is constantly refilled in the container and the Liquid flows off via an overflow, and that the electrolyte liquids in the containers are constant be circulated. 2. Device for performing the method according to claim 1, characterized in that that seen in the running direction of the wire at least behind the first container (4) a liquid scraper and / or a fan or the like is provided. 3. Device for performing the method according to claim 1, characterized in that that the electrodes (9) arranged in the containers have a circular cross-section and the wire runs approximately in the axis of each electrode (9). 4. Apparatus for performing the method according to claim 1, characterized in that that the at least one deflection roller between the contact containers in the first part of the annealing section is arranged. 5. Apparatus according to claim 4, characterized in that around the deflection roller (5) a A collecting ring (38) is provided for the thrown off liquid. 6. Device according to. Claim 5, characterized in that the collecting ring (38) in the lower Part has a drain (40) and that means are provided that a return of the collected Prevent liquid through the openings for the strand-like material. 7. Apparatus according to claim 6, characterized in that at the passage points for the string-like material are arranged in the collecting tube, which extends so far into the liquid-carrying Reach into the channel of the collecting ring so that its upper edge is higher than the liquid level in this gutter. 8. Apparatus according to claim 4, characterized in that the Umlenkrollc (5) is a driven one Role is. 9. Apparatus according to claim 4, characterized in that at least one of the contact container (4, 6) and / or the pulley are adjustable in height. 10. Device for carrying out the method according to claim 1, characterized in that the containers are designed to be hinged open. 11. The device according to claim 1, marked-ί is characterized by two nested to the Container axis mutually rotatable tubes (30, 31), which along a surface line each one Have slot (32, 33). 12. Apparatus for performing the procedural (i rens according to claim 1, characterized by a Measuring and regulating device for keeping the current supply to the wire constant. 13. Apparatus for performing the method according to claim 1, characterized by a 1) Measuring and control device for keeping constant the wire temperature along the annealing section. 14. Apparatus for performing the method according to claim 1, characterized by a Measuring and control device for keeping the temperature of the electrolyte constant. 15. Apparatus for performing the method according to claim 1, characterized by a the conductivity of the electrolyte measuring device, which the supply of electrical lines 2) power to the annealing section and / or the power supply regulates. 16. The method according to claim I, characterized in that that an electrolyte of high electrical conductivity is used. in 17. Apparatus for carrying out the method according to claim 1, characterized in that in the circulation circuit of the electrolyte liquids a cleaning device is provided. 17. The method according to claim 1, characterized in that the wire is in the electrolyte baths is pickled. 19. The method according to claim 1, characterized in that an alternating current is used will. 4 (i 20. The method according to claim 1, characterized by using a direct current and by having at least one contact point is switched so that the electrolyte pickles the strand-like material bright. .τ, 21. The method according to claim 1, characterized in that that different electrolytes are used in the containers (4, 6). 22. The method according to claim 1, characterized in that the strand-like material in the open Vi part of the annealing section after the deflection of one Protective jacket, for example a pipe, is surrounded. 23. The method according to claim 1, characterized in that the strand-like material between , -, the containers run in a protective atmosphere. 24. The method according to claim 1, characterized by the use of environmentally friendly Electrolytes, e.g. B. an electrolyte that reacts neutrally to the outside. _w , 25. Apparatus for carrying out the method according to claim 1, characterized in that the second contact bath (6) of the heating path is preceded by an electrolyte path without an electrode. , ν-, 26. Device according to claim 25, characterized characterized in that the upstream electrolyte line consists of a protruding into the container (6) Tube (51) of relatively small cross-section exists, to which electrolyte is continuously supplied. 27. The device according to claim 25, characterized by one in the running direction of the wire nozzle (46) spraying onto the wire intrittsstelle in the second container (6). 28. The device according to claim 25, characterized in that the electrolyte in the second contact container (6) upstream route is cooled, or that this route continuously cooled electrolyte is supplied and / or that a faster throughput of the electrolyte in this area takes place. 29. Device for performing the method according to claim 1, characterized in that that the electrolyte container are conical at the bottom.