RU2788398C1 - High-performance steel rod quenching plant, quenching machine and corresponding steel rod quenching method - Google Patents

Abstract

FIELD: metallurgy.

SUBSTANCE: invention relates to a plant for quenching steel rods in a continuous mode, containing a quenching machine and a method for quenching steel rods. The plant contains a loading unit (14) suitable for placing a set of individual rods (P) at a distance from each other, the first processing line (11) containing an austenization furnace (16) for receiving the said set of rods (P) located parallel to each other from the loading unit (14) and for performing the first heat treatment of rods (P), in which the austenization furnace (16) contains means (22) for simultaneous feeding of the said set of rods (P) in the feed direction (D1) with simultaneous rotation of them around its axis, in this case, the rods (P) are oriented in the feed direction (D1), the quenching machine (17) located at the outlet of the austenization furnace (16) to perform cooling with respect to the set of rods (P), while the quenching machine (17) has a base (31) and a cover (32) forming an internal the space (35) in which the mentioned means (22) are located for simultaneous supply of a set of rods (P) with simultaneous rotation of them around their axis, determining the reference plane for the rods (P), and a set of cooling elements (36a, 36b), located respectively above and below the means (22) for feeding the rods and made with the ability to spray the cooling fluid on the passing rods (P), while at least a set of cooling elements (36a) located above the rods (P) is made with the ability to adjust their height relative to the plane of feeding the latter, the transmission unit (13) located behind the quenching machine (17), and a second processing line (12) located behind the transmission unit (13) and having a tempering furnace (19) for quenching a set of rods (P), at the same time, the mentioned means for simultaneous feeding of a set of rods (P) with their simultaneous rotation around their axis contain rollers (22), on the surface (23) of which V-shaped recesses (24) determined by an angle (α) are made, and which are oriented relative to the direction of feeding (D1) at an angle other than 90°, and at the same time, the second processing line (12) has rollers located essentially perpendicular to the axis of the rod feed and having a flat support surface of the rods (P).

EFFECT: creating a high-performance continuous type quenching plant that is not excessively bulky, relatively easy to operate and functional, which uses devices that are easy to maintain, and creating an efficient quenching plant with suitable dimensions, creating a quenching machine that provides uniform processing of steel rods and minimizing deformation of the processed rods.

11 cl, 5 dwg

Description

The field of technology to which the invention belongs

The present invention relates to a high-performance plant for hardening steel rods. In particular, the proposed hardening plant is suitable for performing the hardening treatment of several rods at the same time.

The invention also relates to the furnace and hardening machine used in this plant.

In addition, the invention relates to a quenching method in which the above plant and machine are used.

Prerequisites for the creation of the invention

It is known that in order to improve the mechanical properties of metal products, such as, for example, steel rods, the latter are subjected to quenching and tempering. Hardening consists in the fact that steel rods are subjected to one or more heating cycles followed by rapid cooling.

Hardening provides that the steel is subjected to a process divided into at least three main stages, carried out in the following order: strong heating, rapid cooling, and finally the next heating / cooling stage, respectively carried out using suitable devices, such as, for example, a furnace austenitizing, hardening machine and tempering furnace.

For hardening, known installations are used, which make it possible to process one steel rod or groups of rods at a time.

Hardeners can process the rod in a continuous mode, or in a batch or discontinuous mode, as defined below.

Intermittent or intermittent mode provides that the rod (s) is (are) subjected to all types of processing, remaining in almost the same position during almost the entire processing process, that is, during heating and cooling operations.

One of the disadvantages of installations using this intermittent mode is the uneven processing.

In these installations, the steel rod(s) must be kept immobile during processing, resulting in limited penetration (during the heating phase) or removal (during the cooling phase) of heat when the rod(s) is (are) on an appropriate base.

This disadvantage arises both when processing a single rod, and, even worse, in cases where several steel rods are simultaneously processed to increase productivity.

Such a solution leads to the need to place superimposed and/or placed next to each other rods at a distance from each other, or in contact with each other, at different distances from the components of the installation, which leads to uneven processing both in the rod (in in particular, where it rests on and/or comes into contact with parts of the installation), and between the rods.

Hardening plants are also known which are capable of operating continuously to advance the rod during processing, so that the rod moves from one processing stage to another.

Known continuous tempering plants typically process only one rod at a time.

Therefore, the next rod to be processed can enter the machine only after the previous rod has traveled a certain distance, so that a new rod can be placed without the risk of unwanted contacts between the rods.

Thus, the obvious disadvantage of the continuous plant is the significant limitation of productivity due to the processing of the rods individually.

To increase productivity, only one parameter can be changed, namely, the speed of the rod advancement inside the processing machines.

Considering that, due to the conductivity of steel, the distance traveled is limited by the time required to complete each stage (both heating and cooling), and considering that it takes longer for rods of larger diameter to complete each individual stage, it is obvious that with a gradual increase in diameter processed rods, the time between the supply of one rod and the next rod also increases.

This disadvantage is exacerbated with an increase in the diameter of the processed rods.

Due to the physical and thermodynamic requirements associated with the conductivity of the metal of which the rod is made (and with its diameter), the speed of advance of the steel rod cannot be excessively increased. It is necessary to ensure that the rod remains in each stage for a certain amount of time to allow heat to penetrate into the depth of the rod and be removed when cooled, which imposes speed limits for the same plant dimensions.

Therefore, increasing the speed of the rod to increase productivity will entail an increase in the size of the installation, which will lead to a loss in processing efficiency and an inevitable increase in costs.

Thus, the known hardening plants do not allow to increase productivity without compromising the quality of processing, or such plants must be complex, expensive and large.

JP 2011184712 describes a rod heating furnace and a cooling device downstream of this furnace. The rods are transported inside the heating furnace and through the cooling device by a roller conveyor. The cooling device can take a working and retracted position.

CN 109295286 describes a hardening plant comprising a primary hardening device and a secondary hardening device.

It is also known that hardening plants provide rapid cooling of the rods with cooling fluid streams.

It is also known that quenching machines with cooling fluid flows use cascaded flow provided in only one direction, such as radial, or with flow from above or below.

It is also known that such hardening machines use streams whose position/delivery distance in relation to the steel rod, as a rule, cannot be changed.

It is also known that hardening machines use orientable or non-orientable and non-focused cooling fluid flows on certain parts of the rod to be cooled.

It is also known that hardening plants can be equipped with hardening machines that perform rapid cooling by immersion in a cooling fluid contained in a tank.

One of the disadvantages of such immersion cooling is that the movement of the rods inside the tank entails inevitable contact between the rods and the support that moves them, which prevents heat dissipation from these areas.

Another disadvantage is that during the immersion phase, the sections of the rods will be in contact with the cooling fluid at different times.

That is, a disadvantage of these known hardening machines is that the contact between the metal and the cooling fluid is not uniform.

Another disadvantage is that in these hardening machines, the cooling fluid contacts the steel rod at different locations and at different times.

Rapid cooling is a critical step in quenching, as applying a cooling fluid to steel rods in a non-uniform manner or not simultaneously over the entire surface of the rod can affect the uniformity of the hardening quality and compromise the quality of the rods themselves.

Finally, one drawback common to both types of known hardening machines is that the hardening causes deformations and/or bends in the steel bars being processed.

Taking into account all the disadvantages described above, we conclude that there is a need in the industry for a hardening plant that would be free from at least one disadvantage of the prior art.

Therefore, one of the objectives of the invention is to provide a high-performance continuous type hardening plant.

Yet another object of the invention is to provide a hardening plant which is not overly bulky and is relatively easy to operate and functional.

Yet another object of the invention is to provide a hardening plant using devices that are easy to maintain.

Yet another object of the invention is to provide an efficient hardening plant that is suitably sized and that manages costs advantageously.

Another object of the invention is to provide a hardening machine that provides uniform processing of steel rods.

Another object of the invention is to provide a hardening machine that minimizes the deformation of the processed rods.

The Applicant has developed, tested and carried out the present invention in order to overcome the shortcomings of the prior art and achieve these and other objects and advantages.

Brief description of the invention

The present invention is formulated and characterized in independent claims. Dependent claims describe other features or variants of the main idea of the invention.

The invention relates to a hardening plant according to claim 1 of the claims, providing continuous operation, having special technical solutions and geometric parameters and equipped with appropriate devices for high-performance simultaneous hardening of a set of steel rods.

The proposed installation for hardening includes the first and second technological lines connected at one end through the transfer unit.

In one of the embodiments of the invention, these two technological lines are essentially parallel, and the direction of supply of the processed material between the first and second lines is changed by 180°.

Alternatively, the second line is substantially aligned with the first line and is its continuation, so that the transmission node performs only a transition from one line to another without changing direction.

Depending on the area and/or logistics of the plant where the plant is installed, the two production lines can also be located at an angle to each other.

The transfer unit ensures the transfer of steel rods from the first production line to the second.

The steel rods to be processed are fed along the plant by means of feeding means arranged in series along two production lines. Such feed means can be, for example, rollers.

According to the invention, in order to increase productivity, rollers are used in the hardening plant, allowing several rods to be simultaneously fed in parallel close to each other.

According to the invention, at least in the first production line, the rollers have a bearing surface provided with V-shaped recesses suitable for receiving and stabilizing the transported rods.

The rods on which the machine operates may have a diameter of, for example, 15 to 100 mm, although this range should not be considered as a limitation. The V-shaped notches are sized to match the diameter of the bars to be machined.

This shape of the rollers guarantees uniformity of processing, uniformity of metallurgical and mechanical results, prevention of thermal shocks and minimization of cases of deformation of the rods.

The recesses in the rollers are equally spaced and shaped to prevent unwanted vibrations of the rods when they are fed and keep them at the same distance from each other, which guarantees uniform processing.

In addition, the rollers are arranged at such an angle to the feed axis as to cause the rods to rotate along their longitudinal axis as they are fed. In particular, the angle of the rollers relative to the feed direction is different from 90°.

The distance between adjacent rods and their simultaneous rotation makes it possible to ensure that all generatrix surfaces of each of the rods are exposed to the external environment almost uniformly and symmetrically.

An austenitizing furnace is located along the feed line, providing uniform heat radiation along the entire length of the roller and therefore to all the rods located on it, so that even the outermost rods benefit from the characteristics created by the roller itself.

At the outlet of the austenitizing furnace, the rods are quenched by means of a hardening machine, the purpose of which is to drastically reduce the temperature of the rods by means of the cooling fluid flows released by the cooling elements.

If the temperature decrease does not occur evenly throughout the rod, then there is a risk of deformed or poorly hardened rods.

The invention also relates to a hardening machine designed for the proposed installation for hardening steel rods, containing a base and a cover, limiting some internal space.

In this internal space are located the means of supply, which ensure the supply of the rods, while rotating them around its axis. The feed means create a support surface for the rods. In said internal space there are also cooling elements located above and below the supply means and configured to spray the passing rods with a cooling fluid. The rods are moved simultaneously by the feed means in the feed direction in which they lie. The position of the cooling elements located above the rods can be adjusted in height relative to the supply plane.

The distance between the above cooling elements and the rod feeding means can be adjusted to provide a better symmetry of the cooling fluid flows reaching the rods.

In another embodiment, to further optimize the symmetry, the fluid streams are discharged by nozzles, the position of which can be fixed or adjustable, at least in the direction and angle of delivery.

The possibility of such regulation has the additional advantage that, by influencing the arrangement of the nozzles in an appropriate way, it is possible to simultaneously process rods of different diameters.

After the hardening machine, the transfer unit transfers the cooled rods to the second production line. In one of the variants mentioned above, the second line is parallel to the first and has the opposite feed direction.

In one aspect of the invention, the second line has rollers of a different type than those of the first line.

On the second production line, the rollers are located essentially perpendicular to the axis of the rods supply and have a flat surface, which allows, if necessary, to supply a larger number of rods than the rollers of the first line, for example, for transporting rods processed in several cycles and accumulated, for example, in a transfer unit.

In any case, it is also within the scope of the invention to have V-shaped recesses in the second line in the rollers for transporting the rods, as described above with respect to the first production line.

Thus, the invention provides a hardening plant that allows the hardening process to be carried out on a plurality of steel bars simultaneously, and therefore with a productivity increase of a factor essentially equal to the number of bars that can be processed simultaneously, with a guarantee of high quality and uniformity of processing. .

Brief Description of Attached Graphics

These and other aspects, features and advantages of the invention will become apparent from the following description of some of its embodiments, described as non-limiting examples with reference to the accompanying drawings (drawings).

In FIG. 1 is a schematic plan view of a proposed hardening plant.

In FIG. 2 is a transverse perspective view of a roller (and steel rods) for use in the proposed hardening plant.

In FIG. 3a and fig. 3b shows fragments of the roller illustrated in FIG. 2.

In FIG. 4 the proposed hardening machine is shown in cross section.

In FIG. 5 shows in longitudinal section the individual elements of the hardening machine illustrated in FIG. four.

For ease of understanding, the same reference numerals have been used throughout the drawings to refer to identical common elements where possible. It should be clear that the elements and features of one option can be easily included in other options without further explanation.

Detailed description of the invention

The following details various embodiments of the invention, some of which are illustrated in the accompanying drawings. Each example serves the purpose of illustrating the invention and is not intended to be limiting. Features shown or described to the extent that they are part of one embodiment may be adapted or linked to other embodiments to create yet another embodiment. It is clear that all such modifications and variations are included in the scope of the invention.

Before describing the embodiments of the invention, it should be clarified that the present description is not limited in its application to the details of the construction and arrangement of components, as described below with reference to the drawings. The present description may provide other embodiments and may be obtained or performed in various other ways. It should also be clarified that the phraseology and terminology used here is for description only and should not be considered as limiting. The invention relates to a hardening plant, indicated as a whole by 10, capable of continuous operation with a set of steel rods P, see FIG. 1 and FIG. 2.

The following description and the accompanying drawings refer to a hardening plant that allows simultaneous processing of several (in the variant illustrated in Fig. 2, 12) steel rods with a diameter of 15 to 100 mm. It should be clear that, without departing from the scope of the invention, options are possible that allow the simultaneous processing of a different number of rods, as well as rods of different diameters.

In FIG. 1 is a plan view of a hardening plant 10 having two production lines, a first line 11 and a second line 12, which are substantially parallel to each other and have opposite feed directions D1 and D2.

The output end of the first line 11 with respect to the direction of supply is connected to the input end of the second line 12 through the transfer unit 13.

Variants (not shown) are possible in which the first line 11 and the second line 12 are aligned with the supply line or oriented at any angle to each other in accordance with the logistics of the plant and/or due to operational requirements. In this case, the transmission node 13 will be limited to the connection area between the two lines.

The first line 11 includes the first furnace 16, or austenitization furnace, and the hardening machine 17, and steel rods P are fed into its input end through the loading unit 14.

The second line 12 includes a tempering furnace 19 and an unloading unit 20 for unloading the steel bars P.

The first and second lines 11, 12 are provided with a series of rollers oriented transversely to the feed direction D1 and D2 respectively, configured to simultaneously move the plurality of steel bars P along the hardening machine 10.

Rollers can be installed along almost the entire length of lines 11, 12.

The rollers can be arranged more or less close to each other, depending on the requirements.

According to the results of tests carried out by the Applicant by way of example, and not by way of limitation of the scope of the invention, the hardening plant described here can reach a capacity of, for example, from about 3 t/h in the case of steel bars P with a diameter of 50 mm to about 6 t/h in the case of rods P with a diameter of 100 mm.

It is clear that these values are purely indicative and can vary significantly depending on the type of installation and individual production needs, on the number of simultaneously processed rods (it can be increased or reduced), their diameter and on other design parameters of the installation.

The first line 11 of the hardening machine 10 is provided with rollers 22 (see Fig. 2), which have on one surface 23 a plurality of recesses 24, essentially perpendicular to the Z axis of the roller 22, made in the shape of the letter V with an angle α, and ribs 26, wherein each of the recesses 24 is adapted to accommodate a steel rod P. The rollers 22 are an example of a means for simultaneously moving the rods P in the feed direction D1 or D2. In some embodiments, the number of recesses 24 on one roller 22 may be from 6 to 18, preferably from 8 to 16, more preferably from 10 to 14, depending on the number of rods P that must be processed simultaneously, and is compatible with the structural dimensions of the furnaces 16, 19 and hardening machine 17. The roller 22 may have a length measured between the two outermost ribs 26, for example from 1400 to 2000 mm, more preferably from 1600 to 1800 mm. Advantageously, furnace 16 and/or furnace 19 and/or hardening machine 17 are sized to match the length of rollers 22.

Advantageously, recesses 24 are identical and equidistant from each other. The recesses 24 are sized to accommodate a particular range of rod sizes, for example by changing the angle α. Therefore, the height of the ribs 26 will also be changed in order to prevent involuntary and unwanted accidental contacts between the rods P located in adjacent recesses 24.

Some variants provide that the angle α is from 100° to 130°, preferably from 110° to 120°.

In one embodiment of the roller 22 (see Fig. 3a and Fig. 3b), the angle α is approximately 115° and allows steel bars P with a diameter of 15 mm to 100 mm to be stably placed while maintaining them properly and preferably separated from each other for ensure uniform processing and prevent even accidental contact between them.

As can be seen in FIG. 1, the production line 11 may have a number of rollers 22 as shown in FIG. 2, essentially parallel to each other and having a longitudinal axis, at an angle to the feed direction D1 of the steel bars P.

This angle causes the rods P to rotate around the longitudinal axis simultaneously with their feed along line 11.

The hardening plant 10 includes a loading unit 14 that interacts with the input end of the first line 11 and is configured to receive batches of steel rods P to be hardened and correctly send them to the start of processing on the first line 11.

In particular, in the loading unit 14, the rods are spread out, separated and aligned with each other, so that they can be placed one in each recess 24.

In some embodiments, the loading unit 14 can simultaneously load on the rollers 22 the number of rods P, equal to the number of recesses 24.

The loading unit 14 can be configured to introduce one or more rods P into the first line 11, preferably the number of rods P equal to the number of recesses in 24 rollers 22.

Loading can be carried out with both moving and fixed rollers 22.

Preferably, steel rods of approximately the same diameter are loaded. However, cases are not ruled out when simultaneously processed rods P have different diameters.

The steel bars P loaded onto the line 11 are moved from the loading station 14 to the entrance to the furnace 16 where they are taken inside to be heated.

The speed of rotation of the rollers 22 that enter the furnace 16 can be adjusted depending on the required processing time to be observed, for example, depending on the diameter of the steel bars P, the length of the furnace, the temperature inside the furnace 16, based on the design criteria used for the first phases of the hardening process.

At the outlet of the furnace 16, a hardening machine 17, described in detail below, is provided, causing the temperature of the steel bars P to drop sharply at the outlet of the furnace 16 by supplying cooling fluid streams directed to the bars.

The rods P exit through a movable closing baffle which can be closed again when the rods have passed to prevent ambient air from entering the furnace 16 itself.

The exit speed of the rods P is controlled by changing the speed of rotation of the rollers 22, at least the last section of them in the furnace 16, thereby reducing possible temperature imbalances between the two ends of the rod P caused by an excessively long exit time, which makes it possible to improve the hardening process.

The rods P are fed until they reach the output end of the first line 11, entering the transmission node 13.

The transfer unit 13 moves the rods P perpendicular to the direction of movement of the line 11 towards the line 12.

Unlike line 11, line 12 can be provided with a series of rollers with a flat bearing surface for rods P and is designed to move more rods P at the same time, for example 24. In addition, these rollers can be placed not at an oblique angle to the direction of the rods, but perpendicular. Basically, the rollers of the line 12 do not have recesses 24, but have a single bearing surface for the various rods P.

This solution is particularly advantageous during the subsequent tempering process inside the furnace 19, since the rods P are arranged in one layer, increasing the linear weight of the load, thereby increasing the productivity of the furnace.

From the end of the first line 11, the rods P move to a tempering furnace 19 where they undergo a tempering process. Due to the cross-roller feeding structure, the furnace 19 can advantageously be made compact.

In other embodiments, the second production line 12 may contain rollers 22, the execution of which is the same as on the first production line 11.

In other embodiments, the second line 12 may be suitably equipped with a walking beam or Archimedes screw tempering furnace 19 .

After the tempering furnace 19, the steel bars P are sent to an unloading station 20 where, at the end of the process, they can be temporarily stored and/or removed for later use.

The unloading station 20 can be located in close proximity to the loading station 14 and, therefore, be located on the same area, for example, in the building in which the installation 10 for hardening is located. With this solution, it is possible to simplify the operations of the incoming and outgoing transport of the rods P, as well as to reduce the need for personnel.

Next, the proposed hardening machine 17 for cooling the steel bars P at the outlet of the furnace 16 will be described.

In order to understand the advantages provided by the use of hardening machine 17, it is important to consider that, as can be seen in FIG. 3a and fig. 3b, rods P of different diameters have a lower generatrix which remains at a substantially constant distance from the imaginary plane below them, and an upper generatrix which changes its distance from the imaginary plane above.

This aspect is particularly important during cooling by means of fluid streams directed towards the rods P, since known hardening machines are not able to match the height of the fluid stream with the diameter of the rods to be cooled.

As a result, the cooling of the rods can be uneven and/or asymmetric, since the diameter of the rods P can be different, i.e., the cooling fluid can reach more or less extended parts of the rod only partially and/or not at all, which causes their undesirable deformations.

On the other hand, the hardening machine 17 has structural characteristics to ensure very uniform cooling of the steel bars P and at the same time high productivity.

In FIG. 4 and FIG. 5 shows the sections of the hardening machine 17, designed for the needs of the installation 10.

The hardening machine 17 includes a base 31 and a cover 32 forming an interior space 35 in which the rods P supply means and a plurality of cooling elements 36a, 36b located respectively above and below them and configured to spray a cooling fluid onto the steel rods P are placed.

The hardening machine 17 has feed means for simultaneously feeding the rods P, for example, in the feed direction D1. Such feed means may be rollers 22 placed in said inner space 35.

The hardening machine 17 also has means 38 and 39 for height adjustment of at least a plurality of cooling elements 36a located above the rods P.

The rollers 22 provided in the hardening machine 17 have the same characteristics as the rollers in the first furnace 16, i.e. they are recessed to accommodate the individual rods P and are located at an angle other than 90° with respect to the feed direction D1 to ensure rotation of the rods P around its axis when they are fed.

In the considered embodiment, the hardening machine is divided into six sections, but this feature is not limiting. Each section can be adjusted independently of the other sections in terms of flow and pressure of the cooling fluid.

Lid 32 is movable relative to base 31 by means of a lifting element 34, which allows cap 32 to be detached from base 31 and returned to its place, bringing the hardening machine 17 to the open or closed state, respectively.

The closed state is the state adopted for the core hardening process, and the open state is especially beneficial for the maintenance of internal components.

The base 31 contains bearings 33 located opposite each other and aligned in the longitudinal and transverse directions; these bearings 33 are designed to accommodate the two ends of the shaft 25 of the rollers 22.

Means for adjusting the height of the cooling elements 36a may be located on the cover 32, for example. one of their ends was partially located in the inner space 35.

The jacks 38 may be arranged in two substantially parallel lines which may extend at least partially along the longitudinal extension of the lid 32.

Jacks 38 can also be aligned with each other along the transverse axis of the cover 32.

Under the cover 32, a casing 40 is fixed at the ends of the jacks 38 located in the inner space 35.

Attached to and below the shroud 40 are cooling elements 36a substantially parallel to the plane of the roller 22 below.

By actuating the jacks 38, it is possible to adjust the height of the cooling elements 36a with respect to the transmission plane of the steel bars P below, depending, for example, on the diameter of the bars to be cooled at that moment.

In some embodiments, the cooling elements 36a have a stroke that can be between 80 and 90°mm.

The cooling elements 36b are connected to a base 31 located on a plane below the plane of the roller 22 and substantially parallel to it.

The cooling elements 36a, 36b comprise a series of nozzles 42 located along their longitudinal axis and configured to spray a cooling fluid onto the rods P.

In some embodiments, water or mixtures with varying concentrations of polymer or natural and/or mineral oil, or other suitable means, are used as the cooling fluid.

The amount of cooling fluid can be adjusted depending on, for example, the diameter of the steel bars P being processed and/or the height of the nozzles 42 and/or other parameters.

Hardening machine 17 may be equipped with fluid supply and/or purification and recycling facilities (not shown) and/or associated with such facilities suitable to meet the needs for which machine 17 is made.

Nozzles 42 are orientable, that is, capable of spraying cooling fluid at an angle of 20° to 45°, preferably 25° to 40°, more preferably 25° to 35° (see FIG. 5) to horizontal plane rollers. In order to change the feed angle even while moving the rods P under or above the nozzles 42, the latter can be provided with a motor.

Advantageously, the nozzles 42 are oriented in the feed direction of the rods P.

The number of nozzles 42 is preferably equal to the number of recesses 24, but may be more or less.

In some embodiments, the nozzles 42 are equidistant from each other.

The cooling elements 36a, 36b may be staggered so that the angle between them is 30° to 90°, preferably 40° to 80°, more preferably 55° to 65°.

In preferred embodiments, the cooling elements 36a are oriented perpendicularly or at the desired angle to the rollers 22 below.

The cooling elements 36a, 36b may have a length along the longitudinal axis of the hardening machine 17 from 3 to 8 m, preferably from 3 to 7 m, more preferably from 4.5 to 5.5 m.

The cooling elements 36a, 36b are spaced 300 mm to 800 mm apart, preferably 400 mm to 700 mm, more preferably 450 mm to 550 mm apart.

In some embodiments, it is provided that the cooling elements 36a, 36b are preferably, but not necessarily, equidistant from each other.

The number of cooling elements 36a, 36b may be 4 to 24, preferably 6 to 20, more preferably 8 to 16, even more preferably 10 to 14.

By positioning the nozzles 42 both above and below the delivery plane defined by the rollers 22, by allowing the nozzles 42 to be oriented and directed as desired, with the ability to finely adjust the flow and pressure of the cooling fluid in a differentiated manner between sections, and by using rollers 22, which allow the rods 22 to rotate as they are fed, the following is achieved: optimal processing uniformity, reduced environmental impact due to the possibility of eliminating polymers for most steels, as well as easy adaptation of parameters to different processing conditions.

Thus, with the help of the invention, it is possible to maintain the surfaces of the treated rods P at the same distance from the spray mouths of the upper and lower nozzles 42 provided in the hardening machine 17.

The rods P to be machined can have different diameters, for example, you can sequentially process rods with a diameter of 15 mm, rods with a diameter of 30 mm, then rods with a diameter of 50 mm, then again with rods with a diameter of 30 mm, and so on.

In this situation, although the lower generatrix of each of the rods P passing through the installation 10 is always in the same position relative to the point of injection of the cooling fluid, that is, from the mouths of the lower nozzles 42, the upper generatrix, since the rods P are supported from below by the rollers 22 , will tend to approach the mouths of the upper nozzles 42.

This situation is very dangerous in itself, since it can cause distorting effects on the rods caused by uneven cooling, but it is solved by the present invention, providing appropriate measures.

By appropriately driving the engine 39 and the jacks 38, the upper part of the structure can be moved vertically, which supports the respective coolant distribution manifolds or cooling elements 36a provided with nozzles 42.

Thus, the invention guarantees the vertical movement of said upper part of the hardening machine 17, keeping the same upper part absolutely coplanar with the lower part where the cooling elements 36b and the corresponding nozzles 42 are located, in order to always guarantee an ideal distribution of uniform cooling both above and below. In this way, a potential distorting effect is prevented and eliminated.

The invention, which should provide uniform cooling of the "carpet" of rods P, fed and rotated simultaneously, as well as automatic actions to maintain the symmetry of the spray on the surfaces of the rods, also provides a distribution of cooling collectors, that is, cooling elements 36a and 36b, designed to complete and correct cooling surfaces.

The cooling elements 36a are also movable in the vertical direction, therefore, in accordance with the above-described coplanar lifting of the upper spray surface, the nozzles 42 also optimize the supply of the cooling fluid.

As can be seen in FIG. 4 and FIG. 5 and as described above, the nozzles 42 of the cooling elements 36a are oriented so as to create spray cones that effectively and evenly spray the cooling fluid onto the rods P without overlap or collision between them and without excessive distances between them. Orientation angles of the nozzles 42 relative to the horizontal plane defined by the rollers 22 may be from 20° to 45°, preferably from 25° to 40°, more preferably from 25° to 35°.

This hardening machine 17 also proves to be extremely advantageous compared to known hardening machines consisting of one or more "rings", each of which serves to cool a single rod with atomizers directed radially and/or tangentially to it.

Rings with atomizer located radially to the rod, have the disadvantage that the condition for their effective operation is frequent replacement; if the shank diameter varies greatly, the hardening ring must be replaced with another one more suitable for the new shank geometry.

Rings with atomizer tangential to the rod are more adaptable to changes in the geometry of the rod, but have the disadvantage that significant amounts of mechanics are required to control the orientation of the atomizers, which must remain tangent to the surface of the rod when its diameter changes, so this last type of ring, although particularly effective in the case of a single rod or in the absence of performance requirements, it is not well suited for high-performance "multi-rod" solutions.

The proposed hardening machine 17 overcomes both concepts: the special attention paid to the symmetry of the cooling system in the invention contributes to the solution of the problem of producing a hardened product without any changes in the layout of the machine, except that the opening of the machine is controlled automatically by the general control of the production line, which, knowing the diameter of the rods entering the machine allows you to set it to open.

фазы работы установки, используемые при необходимости оптимизировать систему закалки, адаптируя ее к фактически обрабатываемым стержням.This continuity of operation guarantees a significant yield, since the invention virtually eliminates the usual

phases of plant operation, used when necessary to optimize the hardening system, adapting it to the actual processed rods.

The movable cover 32 allows the machine to be fully opened for periodic maintenance or other purposes.

In the proposed hardening machine 17, one has to deal with the problem of a large variation in the diameter of the rods and an almost infinite range of qualities of the steel from which they are made, so it is also possible to use more than one type of cooling fluid or hardening medium and more than one state of different equilibrium in search of fast or less fast hardening.

The concentration of the cooling fluid may be different in different zones of the hardening machine 17, or it may be constant in different zones of the machine. Therefore, the dynamics of the cooling fluid in the invention can be divided into zones using manifolds or cooling elements in a certain area of the machine.

The possibility of using different quenching fluids makes it possible to adapt the quenching machine 17 to different qualities of steel from which the bars P to be quenched are made. A quenching medium such as water that is suitable for a certain type of steel may not be suitable for other steels and may cause cracking or other phenomena. Therefore, the proposed machine can use various types of cooling medium, from water, the temperature of which can be controlled at the inlet, to an infinite number of gradations of a water-polymer mixture or even a cooling oil or other medium.

The rod feed rate was then made adjustable to allow the simultaneous rotation speed of the rods to be increased or decreased under the platform of cooling elements and nozzles.

The proposed hardening plant and hardening machine are designed to improve metallurgical results, which can be adjusted according to requirements.

It is understood that the tempering apparatus, the tempering machine and the tempering method described above may be modified and/or details or steps may be added without departing from the scope and scope of the present invention.

It will also be understood that although the invention has been described with reference to some specific examples, a person skilled in the art will certainly be able to obtain many other equivalent forms of hardening machine, hardening machine and hardening process having the features set forth in the claims and therefore everything that is covered by its scope.

In the following claims, the sole purpose of parenthesized references is to facilitate reading and should not be construed as limiting the scope of protection given by particular claims.

Claims (21)

1. Installation (10) for hardening steel rods in continuous mode, containing - loading unit (14), suitable for placing a set of individual rods (P) at a distance from each other; - the first production line (11) containing an austenitization furnace (16) for receiving said set of rods (P), located parallel to each other, from the loading unit (14) and for performing the first heat treatment of the rods (P), in which the austenitization furnace (16 ) contains means (22) for simultaneous feeding of said set of rods (P) in the feeding direction (D1) with their simultaneous rotation around its axis, while the rods (P) are oriented in the feeding direction (D1), - hardening machine (17) located at the outlet of the austenitizing furnace (16) to perform cooling in relation to the set of rods (P), while the hardening machine (17) has a base (31) and a cover (32) forming an internal space (35 ), in which the mentioned means (22) are located for the simultaneous supply of a set of rods (P) with their simultaneous rotation around its axis, defining a reference plane for the rods (P), and a set of cooling elements (36a, 36b) located respectively above and below means (22) for feeding the rods and made with the ability to spray a cooling fluid on the passing rods (P), while at least a set of cooling elements (36a) located above the rods (P) is made with the ability to adjust their height relative to the plane submission of the latter - a transmission unit (13) located behind the hardening machine (17), and - the second production line (12) located behind the transfer unit (13) and having a tempering furnace (19) for hardening the set of rods (P), while the said means for simultaneously supplying the set of rods (P) with their simultaneous rotation around its axis contain rollers (22), on the surface (23) of which recesses (24) are made in a V-shape, determined by the angle (α), and which are oriented relative to the feed direction (D1) at an angle other than 90°, and at the same time the second technological line (12) has rollers arranged substantially perpendicular to the axis of the rods and having a flat bearing surface of the rods (P). 2. Installation according to claim 1, characterized in that the second line (12) is parallel to the first line (11), while its feed direction (D2) of the rods (P) is opposite to the feed direction (D1) of the first line (11). 3. Installation according to claim 1, characterized in that the second line (12) is aligned or at an angle to the first line (11). 4. Installation according to claim 1, characterized in that the number of recesses (24) provided for each roller (22) is from 6 to 18, preferably from 8 to 16, more preferably from 10 to 14. 5. Installation according to claim. 1, characterized in that the angle (α) is from 100° to 130°, preferably from 110° to 120°. 6. Hardening machine (17) for installation for hardening steel rods (P) according to claim 1, containing a base (31) and a cover (32) forming an inner space (35), characterized in that in the inner space (35) are means (22) for simultaneous supply of a plurality of rods (P) with their simultaneous rotation around its axis, while the supply means (22) determine the reference plane for the rods (P), and cooling elements (36a, 36b) located respectively above and below feed means (22) and configured to spray a cooling fluid onto the passing rods (P), while the rods (P) are able to simultaneously move the feed means (22) in the feed direction (D1), along which the rods (P) lie , and at the same time, at least the cooling elements (36a) located above the rods (P) are made with the possibility of adjusting them in height relative to their plane of delivery. 7. Hardening machine according to claim 6, characterized in that the cooling elements (36a, 36b) comprise nozzles (42) configured to spray cooling fluid onto the rods (P). 8. The hardening machine according to claim 7, characterized in that the nozzles (42) are configured to be oriented at an angle to the horizontal plane, determined by the feed means (22), from 20° to 45°, preferably from 25° to 40°, more preferably from 25° to 35°. 9. Hardening machine according to any one of paragraphs. 7 or 8, characterized in that the nozzles (42) are oriented in the feed direction of the steel rods (P). 10. Hardening machine according to any one of paragraphs. 6-9, characterized in that the mobility of the cover (32) relative to the base (31) is provided by means of a lifting element (34) to selectively bring the hardening machine (17) into an open or closed state. 11. The method of hardening steel rods (P) using the installation according to any one of paragraphs. 1-5 and using a hardening machine according to any one of paragraphs. 6-10, in which the following steps are performed: - place a set of individual rods (P) at a distance from each other, - introduce this set of rods (P) into the austenitization furnace (16), feeding them while rotating them around their axis, - at the exit from the austenitizing furnace (16), the set of rods (P) is rapidly cooled in the hardening machine (17) when the set of rods (P) is supplied with their simultaneous rotation around its axis, while said rapid cooling provides for the supply of cooling fluid from above , and from below these rods (P), - move said set of rods to the tempering furnace (19) to perform hardening treatment of these rods (P), - unload the hardened rods from the tempering furnace (19).

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