EP1352710A2

EP1352710A2 - Motor driven rotary variable speed mechanical system for cleaning wire rods and metal wires

Info

Publication number: EP1352710A2
Application number: EP03004477A
Authority: EP
Inventors: Ferruccio Bellina
Original assignee: TECNOSIDER Srl
Current assignee: TECNOSIDER Srl
Priority date: 2002-04-08
Filing date: 2003-02-27
Publication date: 2003-10-15
Anticipated expiration: 2023-02-27
Also published as: ITMI20020737A1; DE60319173D1; EP1352710A3; ITMI20020737A0; ATE386612T1; EP1352710B1

Abstract

A mechanical system for cleaning wire rods and metal wires, characterized in that said system comprises a first mechanical assembly (1) performing a series of twisting and detwisting operations on the wire material and a series of bending operations in an opposite direction, thereby providing a scaling operation on the wire material, and/or a cleaning assembly (2) comprising a rotary drum (24), therethrough the wire rod or metal wire to be cleaned is caused to pass, and to which abrasive material is supplied.

Description

BACKGROUND OF THE INVENTION

The present invention relates to a motor driven rotary variable speed mechanical system for cleaning wire rods and metal wires.
As is known, mechanical scaling machines have been extensively designed and constructed in recent times, mainly for use in the wire drawing field, in particular for drawing wires having an average low carbon contents.
The success of the above mentioned scaling machines derives of course from economic reasons, but also from environmental aspects, since their use overcome the requirements of pickling the wire rod material, which operation would require greatly polluting and difficult to be disposed of acids.
At present, several drawers, mainly drawing steel wire with a comparatively high average carbon contents, use mechanical scalers designed for replacing the chemical pickling process.
However, presently available mechanical scalers are designed by exclusively exploiting empirical knowledge of the related problems.
Thus, the obtained result has not been found to meet all the conditions required by the drawing process.
Actually, the most important drawbacks affecting available mechanical scaling machines are substantially two:

the first is due to the very great stress to which the wire being processed is subjected as it is wound on excessively small diameter sheaves or pulleys, and on different winding planes.

In this connection it should be pointed out that to wind the wire on sheaves would substantially correspond to elongate the outer fibers of the material.
In actual practice, as a wire rod is caused to be entrained on a small diameter sheave, the wire rod material is work hardened.
Thus, as the wire rod being processed is conveyed to the drawing apparatus, it will be already achieved a work hardening condition due to the above mentioned operating stress, which work hardened condition is much greater than that affecting a not mechanically scaled wire rod material.
Consequently, the overall cross-sectional reduction which could be obtained from a chemically pickled wire rod, cannot be herein achieved, and would be drastically reduced.
Moreover, such a processing treatment frequently causes breakages of the wire rod, mainly in the final processing steps.

The second drawback is related to the surface condition of the wire rod, after having performed thereon the scaling and cleaning operations, which latter are frequently performed by metal brushes.

In fact, the wire rod surface cannot be sufficiently cleaned, and accordingly can include traces of calamine or an excessive amount of very abrading powder thereon.
This drawback, in particular, occurs when the cleaning brushes have been worn, are dirty or are not suitably adjusted.
In such a case, the inner surfaces of the drawing dies would be severely damaged.
Another defect of the wire rod surfaces is their excessive cleaning and brightness.
This would occur with the cleaning brushes in a new or ill adjusted condition.
Thus, such a surface would not provide any gripping for the lubricating material (usually a stearate lubricating material).
Thus, during the drawing operation, the wire rod metal material will directly contact the inner metal material of the drawing die, with a consequent seizure of the operating surfaces.
In this connection it should be moreover pointed out that a mechanical scaling of the wire rods or wire material in general, either with a high or a low carbon contents rate, will constitute, in the immediate future, a broadly used process in drawing shops, since it actually constitutes the sole alternative method to an acid pickling method.

SUMMARY OF THE INVENTION

Accordingly, the aim of the present invention is to provide such an improved scaling system, comprising a mechanical scaling apparatus, specifically designed for meeting the operating requirements to provide a high quality drawing operation, while using a novel system, both with respect to the elimination of calamine, and with respect to the end cleaning of the wire material and its lubricating in the first drawing die.
Within the scope of the above mentioned aim, a main object of the present invention is to provide such a scaling system including a first mechanical assembly, comprising a pulley, driven by a toothed belt through a variable speed motor.
Said pulley is keyed on a shaft fixed to a rotary body.
On the latter are assembled a plurality of sheaves having sheave grooves, designed for applying to the wire rod material a complex movement.
The wire rod material, in particular, is gripped at two end portions thereof at the inlet and outlet of a first mechanical assembly, under an action provided on the wire rod by grippers comprising rollers pressing on the wire rod.
The mentioned two sheaves, in particular, and as stated, provides the wire rod, inside a first scaling mechanical assembly, with a complex movement.
This movement is in part a sinusoidal movement, but it is added to a rotary movement which is applied to the sheaves by a rotary shaft supporting said sheaves.
In this first scaling mechanical assembly, the wire rod is subjected to a pressure stress, at its first inlet portion at the rotary body.
In the second portion of its trajectory, in the mentioned first mechanical scaling assembly, the wire rod is subjected to a reverse twisting operation, since said wire rod is restrained, at said two end portions, by the mentioned gripping rollers.
The twist number to be applied to the wire rod will depend on the linear speed and diameter of said wire rod.
Such a process must be performed also depending on the oxide amount on the surface of the wire rod being processed.
Thus, the treatment process as herein disclosed, prevents the wire rod from being surface work hardened, which would hinder a satisfactory drawing, and which, moreover, would cause a reduction of the wire rod ductility.
Thus, the above disclosed characteristics of the system according to the present invention provides the advantage of preventing, differently from available scalers, any work hardening of the wire rods from occurring.
Accordingly, the device or system according to the invention allows to remove calamine and other impurities from the wire rod, without excessively deforming and work hardening the wire rod material, while operating within the material elastic range, and safely overcoming the negative effects related to the wire rod work hardening.
In this connection, it should be moreover pointed out that in the first mechanical assembly, which constitutes a peculiar feature of the inventive system, the linear speed of the wire rod, in combination with the rotary movement of the sheave assembly arranged inside the scaling machine, provide a given number of twisting and detwisting operations on the wire rod, which inevitably cause a movement of the wire rod surface.
Actually, calamine present on the wire rod surfaces is not always resilient and, as it is subjected to the above mentioned mechanical treatment, it is detached from the wire rod surface.
Actually, not all the oxides which are present on the surface of the wire rod are equal, for nature and thickness.
Because of the above mentioned reasons, the invention provides the possibility of modifying the number of revolutions of the rotor arranged in the first mechanical assembly of the inventive system or apparatus, to perform, with the proper twisting number, those specific processing operations which are necessary for a given type of wire rod.
In this manner, it is suitably possible to limit the deformation or strain of the material, while reducing to a minimum the work hardening thereof, as caused by the mechanical scaling operation.
A further minimum straining action is provided, inside the first mechanical assembly of the system according to the invention, because of the inner path between the operating sheaves.
To that end, depending on the diameter of the wire rod, its hardness, the nature of calamine, the central portion can be easily modified in its geometrical position, to increase or reduce the winding strain or stress.
In this connection it should be pointed out that another functional advantage of the mentioned first mechanical scaling assembly of the inventive system is that the angular arrangement of the twists can be performed from outside, with the machine in operation.
Such a characteristic allows to observe or see, during the process, the surface condition of the wire rod.
Such a feature, moreover, allows to properly set the apparatus or machine to provide the best operating result, with the minimum straining of the wire rod, and this providing a great advantage related to the following drawing operation.
The system according to the present invention further comprises a second mechanical assembly which is used for performing a subsequent cleaning operation on the wire rod surface, to remove possible further traces of calamine.
The mentioned second mechanical assembly comprises a rotary drum, coaxially to which the wire rod is caused to pass, for being subjected to a cleaning process.
Inside the mentioned rotary drum is held an abrasive material of suitable particle size, designed for providing an optimum cleaning action on the wire rod.
Such a cleaning action, in particular, will be improved by pressurized air blowers, one of which is arranged between the first mechanical assembly operating as a scaler proper, and the cleaning assembly proper.
A second blower or blowing assembly is arranged at the outlet of the cleaning device.
In this connection it should be apparent that it would be possible to change the revolution number of the rotary drum of the cleaning device, so as to provide an optimum abrading operation on the surface of the wire rod or wire material.
Actually, it is possible, by operating from outside and with the apparatus in operation, to modify the number of revolution of the drum, to provide an optimum cleaning operation.
In this connection it should be moreover apparent that also the abrading material held in said drum will have a very important effect on the end result.
In fact, this material can be less or more abrading, and it can have either a greater or less specific weight than that of the wire rod material.
In particular, the abrasive or abrading material can comprise metal products, metal-ceramic materials, or can have a sharpened corner configuration.
Of course, all the above mentioned variables will depend on the results to be obtained.
The system according to the invention provides, moreover, to use a rotary die.
Such a rotary die assembly will be arranged at the outlet of the cleaning assembly and it will replace the die of the first operating step of the drawing apparatus.
The used rotary die will provide, moreover, a forced lubricating action on the wire rod.
In particular, the rotary die will complete the drawing process with the cross-section reduction performed in the die, by definitely pressing on the wire rod surface the lubricating material indispensable for performing the drawing operation.
The rotary die applied to the inventive system comprises specifically designed cooling elements allowing the die to be easily replaced.
In this third mechanical assembly, the cooling of the die will be of a direct type and of a spraying nature.
The cooling material, in particular, will be caused to impinge on the die surface with a greatly turbulent movement, thereby overcoming possible air bubbles which would reduce a proper cooling of the die.
Owing to the provision of such a direct cooling device, the die can operate at a lower temperature, while improving its duration and lubricating properties.
The operation for replacing the die constitutes another very useful characteristic, since in the inventive system it is possible to replace the die which can be easily accessed through a top opening.
The above mentioned results, of functional and constructional nature of the improved system according to the present invention have been achieved by a system comprising: a first mechanical assembly performing a series of twisting and detwisting operations on the wire rod and a series of bending operations in opposite directions, thereby providing on the wire rod material a scaling action; a cleaning assembly including a rotary drum therethrough the wire rod to be cleaned is caused to pass, and holding therein an abrading material.

BRIEF DESCRIPTION OF THE DRAWINGS

The above mentioned and other characteristics, of functional and constructional nature of the improved system according to the present invention will become more apparent hereinafter from the figures of the accompanying drawings, where:
Figure 1 is a schematic view showing the system according to the present invention, and in which are clearly shown a scaling assembly, a cleaning assembly and, finally, an improved rotary die holder, including a specifically designed direct cooling device for cooling the die;
Figure 2 is a detail view, in side cross-section, illustrating the details of the first scaling assembly;
Figures 3 and 4 show two cross-sectioned side views of the cleaning assembly with the rotary drum holding an abrading material therein; and
Figure 5 shows the third assembly included in the system according to the invention, said third assembly comprising a rotary die, including a specifically designed direct cooling device for cooling the rotary die.

DESCRIPTION OF THE PREFERRED EMBODIMENTS

With reference to the number references of the accompanying drawings, the system according to the present invention comprises a scaler or scaling assembly 1, including a tubular element 10, therethrough the wire rod or wire material slides, said wire rod being gripped by gripping rollers 11, 12, driven by a driving assembly 13.
Said gripping rollers 11 and 12, in particular, are suitably contoured and are arranged at one end portion of the mentioned first scaling or scaler assembly.
At the outlet of the latter, are provided corresponding gripping rollers 11' and 12' in turn driven by a driving assembly 13'.
The wire material or wire rod F enters a rotary shaft 20, having a perforated inside, and is conveyed to an assembly 16, where it is subjected to a first bending operation, and then to a variously arranged assembly 17, which constitutes an integrating portion of the inventive system.
Then, the wire rod, after having being subjected to a further bending and folding operation, will pass through the sheaves 40 of a third assembly 18, and will axially exit the perforated shaft 20' supporting a pulley driven by an electric motor.
Thus, the assembly including the elements 16, 17 and 18 supporting a plurality of sheaves 40 will exit the hollow shaft 20' and will be gripped by the gripping rollers 11' and 12' driven by the driving assembly 13'.
In this connection it should be pointed out that the wire rod F will be subjected, in the subject scaling device, to a double treatment.
The first comprises a series of bending operations in different directions, applied to the wire rod by the sheaves 40, causing said wire rod to perform a series of bending movements in both directions.
The second movement is applied to the wire rod by the rotary assembly 15, which causes a twisting in the first half of the path and a following twisting, of reverse direction, since the wire rod is restrained at the pairs of gripper rollers 11, 12 and 11', 12' thereby providing such a starting twisting and reverse twisting, at the end portion of the scaling assembly 1.
Said wire rod F is conveyed to a mechanical assembly 2, for cleaning the wire rod or wire material.
In the mentioned cleaning assembly 2, the wire rod F is subjected to a first cleaning process, by blowing, provided on said wire rod at two conveyer and blower devices 22 and 22', coupled at coupling fittings 27 and 27' to a supply duct 28 in turn coupled to a metering valve 29, in turn connected to a pressurized air tank or source.
As shown, the wire rod F passes through a shaft 50, comprising a perforated type, supported by support elements 23 and 23' which further support the rotary drum 24.
The rotary drum 24, in particular, holds in its inside and abrading or abrasive material, having a suitable particle size, configuration and abrading properties, thereby providing a suitable cleaning action on the surface of the air rod being processed.
The rotary speed of the rotary drum 24 can be changed, by using a step by step motor 28 which, through a transmission belt 27, will rotatively drive the pulley 26 keyed on the shaft 50 on which said drum 24 is also mounted.
Then, the wire rod will be conveyed to the third assembly 3 through a perforated tubular element 30, and it will be further conveyed to an assembly 3 comprising a rotary die holder, including a pre-lubricating system for pre-lubricating the wire rod material.
The rotary die holder assembly 36 is driven by an electric motor, which also drives a pulley 31 keyed on the shaft 32 of the die assembly 37.
The latter comprises a spraying device, designed for directly conveying on the surface of the operating die a spray, provided with a turbulent motion, thereby eliminating possible air bubble which would hinder the cooling of the die.
The rotary die holder assembly according to the invention comprises moreover a top opening 34 including a closing door 34' therethrough it is possible to replace in a very easily manner the operating die 38.
Owing to the above mentioned direct cooling, the die can operate at a lower temperature, thereby increasing its duration and improving the lubricating operation.
To prevent any hardened lubricating material plug from being formed in the annular duct 41, which would prevent a regular lubricating of the wire, in the rotary die holder the hole 41 is made eccentrical for few millimeters, from the wire axis, thereby the rotary movement of the body 32 about the wire, will generate and hold an annular gap, in actual practice a tunnel, always in a free condition for facilitating the re-supplying of the lubricating material mainly against the operating die 38.
Thus, the present system comprises a series of mechanical devices including the operating assemblies 1, 2 and 3, the use of which will provide very good mechanical cleaning results, as well as drawing results on the wire rods and wire materials.
In this connection it should be apparent that the disclosed mechanical assemblies can be used either together or separately from one another, the present invention covering all the disclosed assemblies and elements either together or separately considered.
The component elements of the inventive systems can be subjected of variations and modifications, all of which will come within the scope of the invention.

Claims

A mechanical system, for cleaning wire rods and metal wires, characterized in that said system comprises a first mechanical assembly designed for performing a series of twisting and detwisting operations on said wire rod and a series of bending operations in opposite directions, thereby providing a scaling action on the wire rod material and/or a cleaning assembly including a rotary drum therethrough said wire rod to be cleaned is caused to pass and including therein an abrasive material.
A mechanical system, according to Claim 1, characterized in that said scaling assembly (1) comprises a tubular element (10) therethrough said wire rod is caused to slide, said wire rod being gripped at the two end postions thereof by gripping rollers (11), (12) and (11') and (12').
A mechanical system, according to Claim 1, characterized in that said wire rod (F) enter said system through a perforated rotary shaft (20) and is conveyed to a bending assembly (16) where it is subjected to a first bending operation, in a variously arranged assembly (17) and then to a third assembly (18), and exiting through a perforated shaft (20') thereon a pulley is keyed which is rotatively driven by an electric motor.
A mechanical system, according to one or more of the preceding claims, characterized in that said two assemblies (16), (17) and (18) comprises sheaves (40) including a slotted contour.
A mechanical system, according to one or more of the preceding claims, characterized in that said wire rod (F) is subjected, in a first half of the path of said first mechanical assembly, to a twisting operation and, in the second half portion of said path, to a reverse twisting operation.
A mechanical system, according to one or more of the preceding claims, characterized in that in said first scaling assembly, said sheaves (40) compel said wire rod to perform a series of bending movements in both directions.
A mechanical system, according to one or more of the preceding claims, characterized in that said system comprises a cleaning assembly, in which said wire rod (F) is subjected to a cleaning process, by blowing on said wire rod at two conveyor and blower devices (22) and (22') coupled by coupling fittings to a supply duct to a metering valve (29) and a pressurized air tank source.
A mechanical system, according to one or more of the preceding claims, characterized in that said second cleaning assembly comprises a rotary drum (24) the operating speed of which can be varied by operating a step by step motor (28), through a transmission belt transmitting a rotary movement to a pulley (26) keyed on a shaft (50) thereon said drum (24) is also assembled.
A mechanical system, according to one or more of the preceding claims, characterized in that said system comprises a third rotary die holder assembly (36), driven by an electric motor in turn driving a pulley (31) keyed on the shaft (32) of the die assembly (37).
A mechanical system, according to one or more of the preceding claims, characterized in that said die assembly comprises a spraying device, directly conveying on the surface of said die a spray with a remarkable turbulent movement.
A mechanical system, according to one or more of the preceding claims, characterized in that said rotary die holder assembly comprises an opening (34) having a door (34') therethrough it is possible to replace said die (38) by disengaging suitable threaded elements.
A mechanical system, according to one or more of the preceding claims, characterized in that said system comprises a series of constructional elements, to be claimed together and as individually considered, and as broadly disclosed and illustrated in the preceding disclosure and in the several figures of the enclosed drawings, accompanying the present Industrial Invention Patent Application.