RU2317869C1 - Rod drawing method - Google Patents

Abstract

FIELD: lines for drawing rolled rod.

SUBSTANCE: method comprises steps of breaking scale; fine cleaning of rod from residual scale and drawing rod in drawbench with use of soap and drawing tool. Rod is successively drawn through scale breaker. Apparatus for fine cleaning with use of abrasive powders, rod and (or) abrasive powder are subjected to vibration while arranging vibrators relative to axis of rod in such a way that to arrange cleaning zone in place of maximum amplitude of lengthwise oscillations. Under-lubricant layer is applied on surface of rod and then rod is passed through electromagnet whose inlet polarity is changed depending upon predetermined properties of wire. Rod is passed through soap receptacles while drawing tool mounted behind said receptacles is subjected vibration. Vibrators are arranged in such a way that to provide arrangement of drawing tool(s) in zone of maximum amplitude of lengthwise oscillations while electric current of electromagnet, frequency and amplitude of lengthwise oscillations of vibrators are regulated during drawing process according to steel kind and thickness of rod.

EFFECT: reduced power consumption, improved quality of surface and properties of wire, lowered consumption of additional materials.

1 dwg

Description

The invention relates to the field of drawing production and can be used to remove scale from the surface of the wire rod before drawing instead of traditional etching (autonomously or by combining with drawing mills equipped with mechanical descalers).

Currently, the removal of scale from the surface of the wire rod before drawing in steel mills is carried out by etching in sulfuric or hydrochloric acid [1].

However, this method today cannot be considered the most perfect, since it does not ensure the absence of marriage during drawing and is not economically profitable due to the high cost of materials, especially acids, inhibitors and borax.

Known etching defects include grinding, undergrazing, pitting, hydrogen brittleness, corrosion cracking, intergranular corrosion, and the appearance of dark areas with increased roughness on the surface of the wire rod.

To carry out pickling at steel mills, there are pickling compartments, the maintenance of which is not economically viable due to the high costs of environmental measures and the disposal of spent pickling solutions.

The harmful effect of acid fumes on the health of personnel working not only directly with acid, but also on the health of people working in other areas in steel-making workshops is known.

A known line for cleaning and drawing wire [2], containing an unwinding device, a descaler, a unit for mechanical descaling using ferromagnetic abrasive powders and drawing tools. The known line is equipped with a device for magnetizing and cooling the wire, for example, liquid nitrogen.

However, the author’s later studies showed that the effects of simultaneous exposure to a metal of a magnetic field and cold do not add up, so combining these processes in one device is not advisable for economic reasons.

A known line for cleaning and drawing wires [3], characterized in that the wire rod is subjected to sequential cleaning in a descaling agent, in the device for fine descaling using ferromagnetic abrasive powder, a lubricant layer from an adhesive substance, such as rosin, is applied to the wire rod surface and vibrates in front of the soap dish the help of a mechanism made in the form of a roller with cylindrical rollers around the circumference for a more intense capture of technological lubricant.

A disadvantage of the known method implemented in the known wire rod drawing line is the impossibility of vibrating the wire rod with ultrasonic frequency while drawing in the device for fine descaling and in the soap box not only of the first block of the drawing mill, but on all other blocks of the drawing mill.

Another disadvantage of the known method of drawing is the lack of vibration in the soap dish of the drawing tool (die), which could greatly increase the drawing efficiency and quality of the finished wire due to vibration of the die with ultrasonic frequency [4]. However, in the known method of wire drawing [4] is not provided for preliminary cleaning of the wire rod, combined with drawing.

Ultrasonic processing using abrasive particles is also known, but it is applicable only for machining mechanical engineering parts [4].

The aim of the invention is the creation of such a drawing method, which would in a certain way and in a certain sequence directly on the drawing mill of any multiplicity combine all the necessary steps to prepare the surface of the wire rod as it moves and at the same time create the most effective conditions for the wire to pass along the entire drawing route, starting from the descaler and ending with the last drag before winding the finished wire onto a reel.

This goal is achieved by the fact that in the proposed method for wire rod drawing, including descaling, fine cleaning of wire rod from residual scale and actual drawing on a drawing mill of any multiplicity using soap holders and drawing tools, the wire rod is sequentially pulled through the descaler, a device for fine cleaning the wire rod using abrasive powders, including ferromagnetic, while the wire rod and (or) abrasive powder vibrate with a certain ultrasonic frequency and amplitude, and vibration The holes are located relative to the axis of the wire rod so that the cleaning zone is in place of the antinode of longitudinal vibrations, after cleaning the wire rod, a lubricating layer is applied to its surface, for example, a mixture of wood sawdust and rosin, then the wire rod is treated in a constant magnetic field, for example, passing it through a solenoid, this changes its polarity at the inlet of the wire rod into the solenoid, depending on the specified properties of the wire, pass the wire rod through the soap box of the first block of the drawing mill or through the soap dishes of all blocks of the drawing wire and, while the drawing tool installed behind the soap box or soap dish, vibrate with a certain ultrasonic frequency and amplitude, and the vibrator or vibrators are positioned relative to the axis of the wire rod so that the drawing tool or drawing tools are in place of the antinode of longitudinal vibrations, while in the process of drawing the wire rod regulate the current in the solenoid, the frequency and amplitude of the longitudinal vibrations of the vibrators, depending on the grade of steel, the thickness and mechanical strength of adhesion of the scale to the surface of the wire rod , wire drawing speed on each block of the drawing mill, wire diameter on a specific drawing route, as well as the specified mechanical properties of the finished wire. Schematic diagram of the process (technology) drawing according to the proposed method of drawing is shown in the drawing, where

1 - unwinding device

2 - loop catcher

3 - descaler,

4 - a device for fine cleaning the wire rod from residual scale,

5 - vibrator of ultrasonic vibrations of the powder and (or) wire rod,

6 - container with a mixture of wood sawdust and rosin,

7 - solenoid,

8 - soap dish (soap dishes),

9 - drawing tool (drawing tools),

10 - soapbox vibrator (or soapboxes of all blocks of the drawing mill),

11 - the first block of the drawing mill,

12 - the second block of the drawing mill,

13 - N-blocks drawing mill,

14 - coil with finished wire,

15 - winding device

16 - drawing mill of any multiplicity.

Passing the wire rod through the descaler, remove up to 90-95% from the surface of the wire rod.

Passing wire rod through a device for fine cleaning wire rod using abrasive powders, remove the residual layer of scale.

Vibration of the abrasive powder and (or) wire rod is carried out using ultrasonic vibrators, for example magnetostrictive transducers connected to ultrasonic oscillation generators (the generators are conventionally not shown in the diagram).

High-quality cleaning is achieved by controlling the frequency and amplitude of longitudinal vibrations. The cleaning zone is located in the place of the antinode of vibrations, therefore, as a result of vibrations, the movement of abrasive particles is activated, which begin to rotate, that is, roll, along the dross layer, cutting deeply and destroying it.

After cleaning the wire rod from scale, a lubricant layer is applied to its surface, for example, by passing the wire rod through a mechanical mixture of sawdust and rosin powder. As a result, a thin layer of adhesive substance (resin) is formed on the surface of the wire rod, which intensively captures the technological lubricant (soap) and ensures a normal drawing process.

After applying a lubricant layer to the surface of the wire rod, the wire rod is treated in a constant magnetic field, for example, a solenoid (in the diagram, the solenoid power source and control panel are not shown conditionally).

By changing the polarity of the solenoid and the magnetic field, the required mechanical and physical properties of the wire are obtained using the well-known effect of the magnetic field on the metal crystal lattice. Next, a wire rod is passed through the soap box of the first block of the drawing mill (or through the soap dishes of all blocks of the drawing mill), carrying out the actual wire drawing. In this case, the drawing tool (dies) installed in the soap box (or in the soap boxes of all the blocks of the drawing mill), vibrate. The necessary drawing mode along the entire route is provided by controlling the frequency f and the amplitude a of the oscillations, the dependence of which on the drawing speed v on each block can be found by the well-known expression: v <2πaf [4], which is a necessary condition for the effective action of vibrational (pulsed) forces. In this case, the oscillation amplitude can vary from fractions of a micron to a millimeter, and the oscillation frequency (with stepless regulation) can vary from an industrial frequency to 75 kHz or more.

As a result of wire drawing by the proposed method, energy consumption for metal deformation is reduced, the surface quality of the finished wire is improved, the mechanical and physical properties of the wire are improved, and the cost of auxiliary materials is sharply reduced. Economic calculations performed at the Cherepovets Steel Rolling Plant (Severstal-metiz CJSC) showed that as a result of replacing the descaling process from the wire rod surface with the proposed method, the cost of wire rod cleaning directly in the drawing line decreases by about 2.5 times.

Information sources

1. N.P. Zhetvin, F.S. Rakhovskaya, V.I. Ushakov. Scale removal from a metal surface. M.: Metallurgy, 1964, 195 p.

2. RF patent No. 2033290.

3. RF patent No. 2205080.

4. Kumabe D. Vibration cutting. / Per. from japanese.

Ed. I.I. Portnova, V.V. Belova. M .: "Engineering", 1885, 424 p.

Claims (1)

A method of wire drawing, including descaling, fine cleaning of wire rod from residual scale and drawing on a drawing mill of any multiplicity using soap holders and drawing tools, characterized in that the wire rod is pulled sequentially through the descaler, a wire rod fine cleaning device with abrasive powders, including ferromagnetic, this wire rod and / or abrasive powder is subjected to vibration with ultrasonic frequency and amplitude, positioning the vibrators relative to the axis of the wire rod so that it was cleaned at the place of antinode of longitudinal vibrations, after cleaning, a lubricant layer consisting of a mixture of wood sawdust and rosin is applied to the surface of the wire rod, then the wire rod is treated in a constant magnetic field, passing it through a solenoid, with a change in its polarity at the input depending on the specified properties finished wire, wire rod is passed through the soap box of the first block of the drawing mill or through the soap dishes of all blocks of the drawing mill, drawing tools installed behind the soap box or soap holders, vibrate with ultrasonic frequency and amplitude, positioning the vibrator or vibrators relative to the axis of the wire rod so that the drawing tool or drawing tools are in place of the antinode of longitudinal vibrations, while in the process of drawing the wire rod regulate the current in the solenoid, the frequency and amplitude of the vibrators, depending on steel grades, thickness and mechanical adhesion of the scale to the wire rod surface, drawing speed on each block of the drawing mill, wire diameter on a specific m drawing route, as well as the specified mechanical properties of the finished wire.