阅读说明：本技术 一种中粗规格钢丝索氏体化冷却装置及工艺 (Medium-thick steel wire sorbitizing and cooling device and process ) 是由 张洪龙 蒋蕊 张峰山 于 2019-10-29 设计创作，主要内容包括：本发明公开一种中粗规格钢丝索氏体化冷却装置及工艺。该冷却装置是由内置有水泵的蓄水池、内置有两个冷却水套的回水水槽、冷却水塔通过管道相连形成一个冷却水循环系统。该工艺主要采用喷淋和两级分段冷却工艺代替了传统铅浴淬火的急冷工艺,能够有效避免钢丝产生开裂缺陷,保证中粗规格钢丝索氏体化中间热处理的质量,提高钢丝性能和稳定性；同时,本发明具有无污染、低能耗、工艺简单的优点；此外,本发明根据红外测温仪的所测温度来调节两个冷却水套的进水量以及距离,只利用水这一种介质就可以实现不同规格和材质的钢丝对应不同的工艺要求,省去了来回更换淬火介质的麻烦,简化操作、节省成本。(The invention discloses a sorbitizing cooling device and process for medium and thick steel wires. The cooling device is formed by connecting a reservoir with a built-in water pump, a return water tank with two built-in cooling water jackets and a cooling water tower through pipelines. The process mainly adopts a spraying and two-stage sectional cooling process to replace a quenching process of the traditional lead bath quenching, can effectively avoid the cracking defect of the steel wire, ensure the quality of the sorbitizing intermediate heat treatment of the medium and coarse steel wires, and improve the performance and the stability of the steel wire; meanwhile, the invention has the advantages of no pollution, low energy consumption and simple process; in addition, the water inflow and the distance of the two cooling water jackets are adjusted according to the measured temperature of the infrared thermometer, the steel wires with different specifications and materials can meet different process requirements only by using one medium, the trouble of replacing quenching media back and forth is eliminated, the operation is simplified, and the cost is saved.)

1. The utility model provides a thick specification steel wire sorbite cooling device which characterized in that: the device comprises a reservoir (1) internally provided with a water pump (2), a return water tank (6) internally provided with two cooling water jackets (5) and a cooling water tower (8), wherein the two cooling water jackets (5) are respectively communicated with the reservoir (1) through a water inlet pipe (3), and the return water tank (6), the cooling water tower (8) and the reservoir (1) are sequentially communicated through a water outlet pipe (7); the cooling water jacket (5) is formed by embedding a circular truncated cone-shaped inner ring sleeve (5-2) in a cylindrical outer ring sleeve (5-1), aligning one end of the outer ring sleeve with the big end of the inner ring sleeve, and then sealing and connecting the two ends of the outer ring sleeve to form a clamping cavity (5-3) with communicated inner cavities, six rows of spraying holes (5-2-1) distributed along the bus direction are uniformly distributed on the inner ring sleeve (5-2), three water inlet pipe connectors (5-1-1) are uniformly distributed on the left side, the top and the right side of the outer ring sleeve (5-1) at intervals of 90 degrees, the lower part of the outer ring sleeve is seated on an arc-shaped vertical plate (9), the arc-shaped vertical plate (9) is vertically fixed on a horizontal bottom plate (10), and the horizontal bottom plate (10) is matched with the horizontal base (12) in a sliding mode.

2. The apparatus for sorbing a medium gauge steel wire according to claim 1, wherein: the horizontal base plate (10) is provided with a screw claw (11), the horizontal base (12) is provided with a slideway (12-1), and the screw claw (11) is matched with the slideway (12-1).

3. The apparatus for sorbing a medium gauge steel wire according to claim 1, wherein: every two adjacent rows of spraying holes (5-2-1) on the cooling water jacket are arranged at an included angle of 60 degrees, and the number of each row of spraying holes (5-2-1) is 8; an included angle of 120 degrees is formed between the inner ring sleeve (5-2) and the end face of the cooling water jacket, and an included angle of 30 degrees is formed between the incident angle of each spraying hole (5-2-1) and the horizontal direction of forward movement of the steel wire.

4. The apparatus for sorbing a medium gauge steel wire according to claim 1, wherein: and adjusting valves (4) are respectively arranged on the water inlet pipes (3) connected with the two water inlet pipe joints (5-1-1).

5. A process for performing sorbite cooling of medium gauge steel wires using the cooling device of claim 1, characterized in that: the process comprises the following steps:

A. connecting a cooling water circulation system: two cooling water jackets (5) in a return water tank (6) are communicated with a reservoir (1) through a water inlet pipe (3), and then the return water tank (6), a cooling water tower (8) and the reservoir (1) are communicated through a water outlet pipe (7) in sequence to form a cooling water circulation system;

B. starting a cooling water circulation system: starting a water pump (2) built in a reservoir (1), pumping cooling water in the reservoir (1) into a water inlet pipe (3), quickly filling a cooling water jacket (5), and ejecting the cooling water jacket (5) along the axial direction of a spraying hole (5-2-1) opposite to the cooling water jacket (5);

C. two-stage sectional cooling: the steel wires (13) are positioned by the front and the rear two pairs of positioning roller sets (14), longitudinally penetrate through the backwater water tank (6), the two cooling water jackets (5) and the heat preservation pipe (15), and are driven by the power device to linearly move forwards at a constant speed; when the steel wire (13) passes through the first cooling water jacket (5), water columns are sprayed on the surface of one circle of the aligned steel wire by six rows of spraying holes (5-2-1) simultaneously, so that the steel wire (13) is uniformly and slowly cooled in the initial section, the rapid cooling is avoided, and the cracking of the steel wire is avoided; the steel wire cooled in the initial section continuously moves forwards, when the steel wire (13) passes through the second cooling water jacket (5), water columns are sprayed on the surface of one circle of the aligned steel wire from six rows of spraying holes (5-2-1) in the same way, so that the steel wire is cooled in the secondary section correspondingly required, and the temperature of the steel wire is adjusted to reach the temperature required by the process; in the two-stage sectional cooling process, the distance between two cooling water jackets (5) is flexibly and rapidly adjusted by means of the matching of the screw claw (11) and the slide way (12-1), and then the homogenization time of the internal and external temperatures of the medium and thick steel wires with different specifications and materials is adjusted; the water inflow of the cooling water jacket (5) can be flexibly controlled by means of the regulating valve (4), and the temperature which is required to be reached by the medium and thick steel wires with different specifications and materials after being cooled corresponding to each section is further controlled;

D. isothermal transformation: the steel wire after two-stage sectional cooling continues to move forward and enters the heat-insulating pipe (15) for isothermal transformation, so that the temperature inside and on the surface of the steel wire is fully homogenized, and the tissue transformation is completed;

E. monitoring the temperature: an infrared thermometer (16) is arranged around the steel wire which penetrates out of the heat preservation pipe (15), and the actual temperature of the steel wire finally obtained after cooling is monitored in real time.

6. The process of claim 5, wherein the cooling comprises the steps of: the cooling water is normal temperature water.

7. The process of claim 5, wherein the cooling comprises the steps of: the cooling water pumped into the water inlet pipe (3) and the cooling water jacket (5) is high-pressure water with the water pressure of 1-3 MPa.

Technical Field

The invention belongs to the technical field of heat treatment of metal products, and particularly relates to a sorbitizing cooling device and process for medium and thick steel wires.

Background

In the production process of the high-carbon steel wire, the steel wire needs to be subjected to sorbitizing intermediate heat treatment. Until now, the traditional common method is patenting, which comprises the following steps: after being unfolded, the steel wire is heated to about 910 ℃ at high temperature and then quickly enters a lead bath at about 500 ℃ to finish the rapid cooling and isothermal transformation of the steel wire. The traditional lead bath quenching process has the advantages of stable and easily controlled process and easily ensured mechanical property of the steel wire, thereby being widely applied to the production of the steel wire. However, the lead bath quenching process also has serious disadvantages: 1. lead is a toxic substance, and is extremely harmful to human bodies if contacted for a long time; 2. the melting point of lead is 327.5 ℃, and after the lead is heated to 500 ℃, on one hand, a large amount of energy is consumed, on the other hand, the lead is easy to volatilize to cause environmental pollution, and the newly-released national relevant policy clearly stipulates that the heat treatment lead furnace is a obsolete device; 3. in the production, the surface state of the steel wire is not ideal, so that the steel wire is lead-coated, not only is the lead resource consumed, but also the surface and other properties of the steel wire are influenced by the subsequent lead-drawing bath quenching process.

Although the heat treatment industry at home and abroad always searches for a sorbitizing treatment method capable of replacing lead, namely, directly and hydrophilically wetting steel wires into water or other quenching media and controlling the cooling capacity by controlling time, the instability of the performance of the steel wires is easily caused due to the instability of local solution temperature. At present, the alternative treatment method is generally applied to thin-specification steel wires, and the problems of surface quenching cracks and the like are often caused when the alternative treatment method is applied to medium-thick-specification steel wires.

Disclosure of Invention

The invention aims to provide a sorbitizing cooling device and a sorbitizing cooling process for medium-thick steel wires aiming at the defects in the prior art. The invention mainly adopts the spraying and two-stage sectional cooling process to replace the quenching process of the traditional lead bath quenching, can effectively avoid the cracking defect of the steel wire, ensure the quality of the sorbitizing intermediate heat treatment of the medium and coarse steel wires and improve the performance and the stability of the steel wire; meanwhile, the invention has the advantages of no pollution, low energy consumption and simple process; in addition, the water inflow and the distance of the two cooling water jackets are adjusted according to the measured temperature of the infrared thermometer, the steel wires with different specifications and materials can meet different process requirements only by using one medium, the trouble of replacing quenching media back and forth is eliminated, the operation is simplified, and the cost is saved.

The object of the invention can be achieved by the following technical measures:

the invention relates to a medium and thick steel wire sorbite cooling device, which comprises a reservoir with a built-in water pump, a return water tank with two built-in cooling water jackets, and a cooling water tower, wherein the two cooling water jackets are respectively communicated with the reservoir through water inlet pipes; the cooling water jacket is a clamping cavity formed by aligning one end of the outer ring sleeve with the big end of the inner ring sleeve and then sealing and connecting the two ends of the outer ring sleeve with the big end of the inner ring sleeve to form an inner cavity for communication, six rows of spraying holes distributed along the bus direction are uniformly distributed on the inner ring sleeve (the cooling water is sprayed along the axis direction of the spraying holes which are aligned with the cooling water jacket, when a steel wire to be cooled horizontally penetrates through the cooling water jacket, water columns are simultaneously sprayed on the circle surface of the steel wire by the six rows of spraying holes, so that the steel wire is uniformly cooled in the circumferential direction, namely, when the steel wire is uniformly and slowly cooled in the initial section by the first cooling water jacket, the rapid cooling is avoided, the steel wire is prevented from cracking, when the steel wire is cooled in the corresponding required secondary section by the second cooling water jacket, the temperature of the steel wire is adjusted to reach the process required temperature, so as to obtain the proper steel wire performance), three water inlet pipe joints are uniformly distributed at the left, the lower part of the outer ring sleeve is seated on the arc-shaped vertical plate, the arc-shaped vertical plate is vertically fixed on the horizontal bottom plate, and the horizontal bottom plate is matched with the horizontal base in a sliding mode.

According to the invention, the screw claw is arranged on the horizontal bottom plate, the slide way is processed on the horizontal base, and the screw claw is matched with the slide way (the distance between the two cooling water jackets is flexibly and rapidly adjusted by means of the matching of the screw claw and the slide way, so that the homogenization time of the internal and external temperatures of the medium and thick steel wires with different specifications and materials is adjusted).

In the invention, every two adjacent rows of spray holes on the cooling water jacket are arranged at an included angle of 60 degrees (six rows of spray holes are uniformly distributed on the surface of the inner ring sleeve), and the number of each row of spray holes is 8; an included angle of 120 degrees is formed between the inner ring sleeve and the end face of the cooling water jacket, and an included angle of 30 degrees is formed between the incident angle of each spraying hole and the horizontal direction of forward movement of the steel wire (namely, an included angle of 60 degrees is formed between the incident angle of each spraying hole and the surface of the large-diameter end of the inner ring sleeve).

The water inlet pipes connected with the two water inlet pipe joints are respectively provided with an adjusting valve (the water inflow of the cooling water jacket can be flexibly controlled by the adjusting valves, and the temperature which is required to be reached after the steel wires with different specifications and materials are cooled corresponding to each section is further controlled, so that the proper steel wire performance is obtained).

The invention relates to a sorbitizing and cooling process for medium and thick steel wires, which is characterized by comprising the following steps of: the process comprises the following steps:

A. connecting a cooling water circulation system: two cooling water jackets in a return water tank are communicated with a reservoir through a water inlet pipe, and then the return water tank, a cooling water tower and the reservoir are communicated through a water outlet pipe in sequence to form a cooling water circulation system (the cooling water circulation system realizes the recycling of normal-temperature water as cooling water, and has no toxicity, no pollution and cost saving;

B. starting a cooling water circulation system: starting a water pump built in the reservoir, pumping cooling water in the reservoir into a water inlet pipe, quickly filling the cooling water jacket, and ejecting the cooling water jacket along the axial direction of the spraying hole opposite to the cooling water jacket (cooling the steel wire moving along the axial direction of the cooling water jacket in a spraying manner);

C. two-stage sectional cooling: the steel wire which is positioned by a front pair of positioning roller sets and a rear pair of positioning roller sets (ensuring that the steel wire horizontally moves forwards along the center of the cooling water jacket) and longitudinally penetrates through the water return water tank, the two cooling water jackets and the heat preservation pipe moves forwards linearly at a constant speed under the drive of a power device; when the steel wire passes through the first cooling water jacket, water columns are simultaneously sprayed to the surface of one circle of the aligned steel wire through six rows of spraying holes, so that the steel wire is uniformly and slowly cooled in the initial section, the rapid cooling is avoided, and the cracking of the steel wire is avoided; the steel wire cooled in the primary section continuously moves forwards, when the steel wire passes through the second cooling water jacket, water columns are sprayed on the surface of one circle of the steel wire from six rows of spraying holes simultaneously in the same way, so that the steel wire is cooled in the secondary section correspondingly, and the temperature of the steel wire is adjusted to reach the temperature required by the process; in the process of two-stage sectional cooling, the distance between two cooling water jackets is flexibly and rapidly adjusted by means of the matching of the screw claw and the slide way, and further the internal and external temperature homogenization time of medium and thick steel wires with different specifications and materials is adjusted; the water inflow of the cooling water jacket can be flexibly controlled by means of the regulating valve, so that the temperature (to obtain proper steel wire performance) required by cooling each section of medium and thick steel wires of different specifications and materials is controlled;

D. isothermal transformation: the steel wire after two-stage sectional cooling continues to move forward and enters the heat-insulating tube for isothermal transformation, so that the temperature inside and on the surface of the steel wire is fully homogenized, and the tissue transformation is completed;

E. monitoring the temperature: and arranging an infrared thermometer around the steel wire which penetrates out of the heat preservation pipe, and monitoring the actual temperature of the steel wire finally obtained after cooling in real time.

The cooling water is normal temperature water.

The cooling water pumped into the water inlet pipe and the cooling water jacket is high-pressure water with the water pressure of 1-3 MPa.

The working principle of the invention is as follows:

the invention mainly adopts the spraying and two-stage sectional cooling process to replace the quenching process of the traditional lead bath quenching, can effectively avoid the cracking defect of the steel wire, ensure the quality of the sorbitizing intermediate heat treatment of the medium and coarse steel wires and improve the performance and the stability of the steel wire; meanwhile, the invention has the advantages of no pollution, low energy consumption and simple process; in addition, the water inflow and the distance of the two cooling water jackets are adjusted according to the measured temperature of the infrared thermometer, the steel wires with different specifications and materials can meet different process requirements only by using one medium, the trouble of replacing quenching media back and forth is eliminated, the operation is simplified, and the cost is saved.

More specifically, during the forward movement of the steel wire in the cooling section, the steel wire is sequentially subjected to primary cooling and the primary cooling through the two cooling water jackets, namely, the surface of the steel wire is slowly cooled in sections by cooling water stabs ejected from the spray holes when the steel wire approaches each cooling water jacket. The steel wire is firstly cooled in the primary section through the first cooling water jacket, the heat conductivity coefficient of water is far smaller than that of lead, the spraying type heat transfer performance is far lower than that of a dipping bath type heat transfer performance, and the temperature difference change of the steel wire before and after primary section cooling is far smaller than that of a traditional lead bath quenching mode, so that the steel wire is effectively prevented from cracking by adopting the aqueous medium for spraying type primary section cooling, the quality of sorbitizing intermediate heat treatment of medium and coarse steel wires is ensured, and the performance and the stability of the steel wire are improved. The steel wire after the primary cooling is cooled by the second cooling water jacket for the second time, so that the temperature of the steel wire can be flexibly adjusted to reach the temperature required by the process, the distance between the two cooling water jackets can be quickly adjusted through the slide way screw claw, and the water inflow of the two cooling water jackets can be adjusted through adjusting the valve, so that the steel wires with different specifications and materials can meet different process requirements only by using one medium, the trouble of replacing the quenching medium back and forth is saved, the operation is simplified, and the cost is saved.

The invention has the following beneficial technical effects:

the invention mainly adopts the spraying and two-stage sectional cooling process to replace the quenching process of the traditional lead bath quenching, can effectively avoid the cracking defect of the steel wire, ensure the quality of the sorbitizing intermediate heat treatment of the medium and coarse steel wires and improve the performance and the stability of the steel wire; meanwhile, the invention has the advantages of no pollution, low energy consumption and simple process; in addition, the water inflow and the distance of the two cooling water jackets are adjusted according to the measured temperature of the infrared thermometer, the steel wires with different specifications and materials can meet different process requirements only by using one medium, the trouble of replacing quenching media back and forth is eliminated, the operation is simplified, and the cost is saved.

Drawings

FIG. 1 is a schematic diagram of the apparatus arrangement and process flow diagram of the present invention.

FIG. 2 is a schematic view showing the connection of the cooling water circulation system according to the present invention.

Fig. 3 is a schematic view of the structure of the cooling water jacket of the present invention.

Part numbers in the drawings: 1. the device comprises a water storage tank, 2 parts of a water pump, 3 parts of a water inlet pipe, 4 parts of a regulating valve, 5 parts of a cooling water jacket, 5 parts of 1 part of an outer ring sleeve, 5 parts of 1 part of a water inlet pipe joint, 5 parts of 2 parts of an inner ring sleeve, 5 parts of 2 parts of 1 part of a spray hole, 5 parts of 3 parts of a clamping cavity, 6 parts of a return water tank, 7 parts of a water outlet pipe, 8 parts of a cooling water tower, 9 parts of an arc-shaped vertical plate, 10 parts of a horizontal bottom plate, 11 parts of a positioning roller set, 12 parts of a horizontal base, 12 parts of 1 part of a sliding way, 13 parts of a steel wire, 14 parts.

Detailed Description

The invention is further described below with reference to the figures and examples:

as shown in figures 1, 2 and 3, the sorbite cooling device for the medium and thick steel wires comprises a water storage tank (1) with a built-in water pump (2), a water return tank (6) with two built-in cooling water jackets (5) and a cooling water tower (8), wherein the two cooling water jackets (5) are respectively communicated with the water storage tank (1) through a water inlet pipe (3), the water return tank (6), the cooling water tower (8) and the water storage tank (1) are sequentially communicated through a water outlet pipe (7) (the components are communicated to form a cooling water circulation system, so that the recycling of normal temperature water serving as cooling water is realized, and the recycling is nontoxic, pollution-free and cost-saving; the cooling water jacket (5) is formed by embedding a circular truncated cone-shaped inner ring sleeve (5-2) in a cylindrical outer ring sleeve (5-1), aligning one end of the outer ring sleeve with the big end of the inner ring sleeve, sealing and connecting the two ends of the outer ring sleeve to form a clamping cavity (5-3) with communicated inner cavities, and six rows of spraying holes (5-2-1) distributed along the bus direction are uniformly distributed on the inner ring sleeve (5-2) (cooling water is ejected along the axial direction of the spraying holes just opposite to the cooling water jacket, when a steel wire to be cooled horizontally penetrates through the cooling water jacket, water columns are simultaneously ejected by the six rows of spraying holes in alignment with the circle surface of the steel wire, so that the steel wire is uniformly cooled in the circumferential direction, namely, when the steel wire passes through a first cooling water jacket to be uniformly and slowly cooled in a primary section, the rapid cooling is avoided, the cracking of the steel wire is avoided, when the steel wire passes through a, to obtain proper steel wire performance), three water inlet pipe connectors (5-1-1) are uniformly distributed on the left side, the top and the right side of an outer ring sleeve (5-1) at intervals of 90 degrees (ensuring that the water pressure of six groups of spraying holes is basically consistent), the lower part of the outer ring sleeve is seated on an arc-shaped vertical plate (9), the arc-shaped vertical plate (9) is vertically fixed on a horizontal bottom plate (10), and the horizontal bottom plate (10) is matched with a horizontal base (12) in a sliding mode.

According to the invention, the screw claw (11) is arranged on the horizontal bottom plate (10), the slide way (12-1) is processed on the horizontal base (12), and the screw claw (11) is matched with the slide way (12-1) (the distance between two cooling water jackets can be flexibly and rapidly adjusted by means of the matching of the screw claw and the slide way, so that the internal and external temperature homogenization time of medium and thick steel wires of different specifications and materials can be adjusted.

In the invention, every two adjacent rows of spraying holes (5-2-1) on the cooling water jacket are arranged at an included angle of 60 degrees (six rows of spraying holes are uniformly distributed on the surface of the inner ring sleeve), and the number of each row of spraying holes (5-2-1) is 8; an included angle of 120 degrees is formed between the inner ring sleeve (5-2) and the end face of the cooling water jacket, and an included angle of 30 degrees is formed between the incident angle of each spraying hole (5-2-1) and the horizontal direction of forward movement of the steel wire (namely, an included angle of 60 degrees is formed between the incident angle and the surface of the large-diameter end of the inner ring sleeve).

According to the invention, the water inlet pipes (3) connected with the two water inlet pipe joints (5-1-1) are respectively provided with the regulating valve (4) (the water inflow of the cooling water jacket can be flexibly controlled by means of the regulating valves, so that the temperature required by cooling each section of medium and thick steel wires with different specifications and materials is controlled, and the proper steel wire performance is obtained).

The invention relates to a sorbitizing and cooling process for medium and thick steel wires, which is characterized by comprising the following steps of: the process comprises the following steps:

A. connecting a cooling water circulation system: two cooling water jackets (5) in a return water tank (6) are communicated with a reservoir (1) through a water inlet pipe (3), and then the return water tank (6), a cooling water tower (8) and the reservoir (1) are communicated through a water outlet pipe (7) in sequence to form a cooling water circulation system (the cooling water circulation system realizes the recycling of normal temperature water as cooling water, and has no toxicity, no pollution and cost saving;

B. starting a cooling water circulation system: starting a water pump (2) built in a reservoir (1), pumping cooling water in the reservoir (1) into a water inlet pipe (3), quickly filling a cooling water jacket (5), and ejecting the cooling water jacket (5) along the axial direction of the spraying holes (5-2-1) opposite to the cooling water jacket (5) (cooling a steel wire moving along the axial direction of the cooling water jacket in a spraying manner);

C. two-stage sectional cooling: the steel wire (13) which is positioned by a front pair of positioning roller sets and a rear pair of positioning roller sets (14) (ensuring that the steel wire horizontally moves forwards along the center of the cooling water jacket) and longitudinally penetrates through the water return water tank (6), the two cooling water jackets (5) and the heat preservation pipe (15) moves forwards linearly at a constant speed under the drive of a power device; when the steel wire (13) passes through the first cooling water jacket (5), water columns are sprayed on the surface of one circle of the aligned steel wire by six rows of spraying holes (5-2-1) simultaneously, so that the steel wire (13) is uniformly and slowly cooled in the initial section, the rapid cooling is avoided, and the cracking of the steel wire is avoided; the steel wire cooled in the initial section continuously moves forwards, when the steel wire (13) passes through the second cooling water jacket (5), water columns are sprayed on the surface of one circle of the aligned steel wire from six rows of spraying holes (5-2-1) in the same way, so that the steel wire is cooled in the secondary section correspondingly required, and the temperature of the steel wire is adjusted to reach the temperature required by the process; in the two-stage sectional cooling process, the distance between two cooling water jackets (5) is flexibly and rapidly adjusted by means of the matching of the screw claw (11) and the slide way (12-1), and then the homogenization time of the internal and external temperatures of the medium and thick steel wires with different specifications and materials is adjusted; the water inflow of the cooling water jacket (5) can be flexibly controlled by means of the regulating valve (4), and the temperature (to obtain the proper steel wire performance) required by the steel wires with different specifications and materials after being cooled corresponding to each section is further controlled;

D. isothermal transformation: the steel wire after two-stage sectional cooling continues to move forward and enters the heat-insulating pipe (15) for isothermal transformation, so that the temperature inside and on the surface of the steel wire is fully homogenized, and the tissue transformation is completed;

E. monitoring the temperature: an infrared thermometer (16) is arranged around the steel wire which penetrates out of the heat preservation pipe (15), and the actual temperature of the steel wire finally obtained after cooling is monitored in real time.

The cooling water is normal temperature water.

The cooling water pumped into the water inlet pipe (3) and the cooling water jacket (5) is high-pressure water with the water pressure of 1-3 MPa.