阅读说明：本技术 一种基于斯太尔摩法高碳钢长材表面氧化物控制方法 (Stelmor method based high-carbon steel long material surface oxide control method ) 是由 唐伟 柯晓涛 邓通武 于 2021-08-24 设计创作，主要内容包括：本发明公开了一种基于斯太尔摩法高碳钢长材表面氧化物控制方法,该方法包括：斯太尔摩风冷线吐丝温度控制,基于高碳钢长材的目标用户是酸洗法剥壳用户还是机械法剥壳用户,对吐丝温度进行相应地控制；斯太尔摩风冷线冷速控制,对吐丝获得的高碳钢长材进行两段式分段冷却,第一段为从吐丝温度至相变温度的急冷阶段,第二段为从相变温度至集卷温度的缓冷阶段,基于高碳钢长材的目标用户是酸洗法剥壳用户还是机械法剥壳用户,对缓冷阶段的冷速以及集卷温度进行相应地控制。采用本发明提供的方法生产的高碳钢长材表面能够满足酸洗法剥壳用户/机械法剥壳用户的个性化要求,覆盖面广。(The invention discloses a stelmor method-based control method for surface oxides of high-carbon steel long materials, which comprises the following steps: controlling the spinning temperature of the stelmor air-cooled line, and correspondingly controlling the spinning temperature based on whether a target user of the high-carbon steel long material is an acid pickling method shelling user or a mechanical method shelling user; the stelmor air-cooled linear cooling speed control is used for carrying out two-section sectional cooling on a high-carbon steel long material obtained by spinning, wherein the first section is a rapid cooling stage from the spinning temperature to the phase change temperature, the second section is a slow cooling stage from the phase change temperature to the coil collecting temperature, and the cooling speed and the coil collecting temperature in the slow cooling stage are correspondingly controlled based on whether a target user of the high-carbon steel long material is a pickling method shelling user or a mechanical method shelling user. The surface of the high-carbon steel long material produced by the method provided by the invention can meet the individual requirements of a pickling method husking user/a mechanical method husking user, and the coverage is wide.)

1. A stelmor method based high-carbon steel long material surface oxide control method is characterized by comprising the following steps:

controlling the spinning temperature of the stelmor air-cooled line, and correspondingly controlling the spinning temperature based on whether a target user of the high-carbon steel long material is an acid pickling method shelling user or a mechanical method shelling user;

the stelmor air-cooled linear cooling speed control is used for carrying out two-section sectional cooling on a high-carbon steel long material obtained by spinning, wherein the first section is a rapid cooling stage from the spinning temperature to the phase change temperature, the second section is a slow cooling stage from the phase change temperature to the coil collecting temperature, and the cooling speed and the coil collecting temperature in the slow cooling stage are correspondingly controlled based on whether a target user of the high-carbon steel long material is a pickling method shelling user or a mechanical method shelling user.

2. A stelmor-based high carbon steel long surface oxide control method according to claim 1, wherein a laying temperature selected when a target user of the high carbon steel long is an acid pickling-method shelling user is lower than a laying temperature selected when the target user of the high carbon steel long is a mechanical shelling user.

3. The stelmor-based surface oxide control method of a high-carbon steel long material according to claim 2, wherein when a target user of the high-carbon steel long material is an acid pickling shelling user, a spinning temperature is controlled to 840 ± 10 ℃; when the target user of the high-carbon steel long material is a mechanical shelling user, the spinning temperature is controlled to be 920 +/-10 ℃.

4. The method for controlling surface oxides of a long high carbon steel sheet according to stelmor process of claim 1, wherein the laying temperature is controlled by controlling the outlet temperature of the finish rolling and the inlet water amount and the water pressure of the water tank after the finish rolling.

5. The stelmor-based high carbon steel long surface oxide control method according to claim 1, wherein a cooling rate range of a slow cooling stage selected when a target user of the high carbon steel long is an acid pickling peeling user is different from a cooling rate range of a slow cooling stage selected when a target user of the high carbon steel long is a mechanical peeling user.

6. The stelmor-based surface oxide control method for the high-carbon steel long product according to claim 5, wherein when the target user of the high-carbon steel long product is an acid pickling shelling user, the slow cooling stage surface cooling rate is 2.0 ℃/s to 3.0 ℃/s, and when the target user of the high-carbon steel long product is a mechanical shelling user, the slow cooling stage surface cooling rate is 1.0 ℃/s to 1.5 ℃/s.

7. The stelmor-based surface oxide control method of a high-carbon steel long product according to claim 1, wherein a cooling rate range of the quenching stage selected when the target user of the high-carbon steel long product is an acid pickling-method shelling user is the same as a cooling rate range of the quenching stage selected when the target user of the high-carbon steel long product is a mechanical shelling user.

8. The stelmor-based surface oxide control method of a high-carbon steel long material according to claim 7, wherein the cooling rate range of the quenching stage selected when the target user of the high-carbon steel long material is an acid pickling-method shelling user and the cooling rate range of the quenching stage selected when the target user of the high-carbon steel long material is a mechanical shelling user are both equal to or greater than 8.0 ℃/s.

9. The stelmor method-based surface oxide control method for the long high-carbon steel material according to claim 1, wherein the cooling rate control is realized by controlling the opening degree of a fan, the opening/closing of a heat-insulating cover and the speed of a roller; in an urgent needIn the cold stage, the corresponding opening degree of the fan is 100 percent, and the air quantity is 20 ten thousand meters³The corresponding heat preservation cover is completely opened; in the slow cooling stage, the opening degree of the corresponding fan is 0%, when the target user of the high-carbon steel long material is a pickling method shelling user, the corresponding heat-insulating cover is completely opened, and when the target user of the high-carbon steel long material is a mechanical method shelling user, the corresponding heat-insulating cover is completely closed.

10. The stelmor-based surface oxide control method of a high-carbon steel long material, according to claim 1, wherein when a target user of the high-carbon steel long material is an acid pickling shelling user, the reform temperature is controlled to 350 ± 10 ℃; when the target user of the high-carbon steel long material is a mechanical shelling user, the bundling temperature is controlled to be 450 +/-10 ℃.

Technical Field

The invention belongs to the technical field of metallurgy, and relates to a control method for oxides on the surface of a high-carbon steel long material based on a stelmor method, in particular to a method for controlling oxides by air cooling.

Background

The high-carbon steel long material is an important raw material for preparing high-strength prestressed steel wires and steel strands, a layer of metal oxide is inevitably formed on the surface of the hot-rolled long material after high-temperature spinning under the air cooling condition, the stripping effect before drawing is influenced by the difference of the thickness and microstructure of the oxide, if the oxide is not removed, cracks or even fracture are easily formed on the surface in the drawing process, and the production efficiency is seriously influenced. At present, the descaling process includes a mechanical method and an acid pickling method. The mechanical method requires that the oxide on the surface of the long material falls off in a massive manner in the repeated bending process, the surface is smooth after falling off, drawing lubricating powder is easily smeared on the surface, and the thickness of a lubricating film is uniform; the pickling method requires that the oxide is easily dissolved in acid, the acid consumption is low, and the problem of surface defects caused by over-pickling and under-pickling cannot occur.

In view of the different requirements of the long product surface oxide by different descaling processes, how to make the long product surface oxide meet or adapt to the individual requirements of different target users needs to be researched.

Disclosure of Invention

In order to solve the technical problems, the invention provides a method for controlling the surface oxide of the high-carbon steel long material based on the stelmor method, so that the surface oxide of the long material meets or adapts to the individual requirements of users of a mechanical method and an acid pickling method.

In order to achieve the purpose, the invention adopts the following technical scheme:

according to an aspect of the present invention, there is provided a surface oxide control method for a high carbon steel long material based on a stelmor method, comprising:

controlling the spinning temperature of the stelmor air-cooled line, and correspondingly controlling the spinning temperature based on whether a target user of the high-carbon steel long material is an acid pickling method shelling user or a mechanical method shelling user;

the stelmor air-cooled linear cooling speed control is used for carrying out two-section sectional cooling on a high-carbon steel long material obtained by spinning, wherein the first section is a rapid cooling stage from the spinning temperature to the phase change temperature, the second section is a slow cooling stage from the phase change temperature to the coil collecting temperature, and the cooling speed and the coil collecting temperature in the slow cooling stage are correspondingly controlled based on whether a target user of the high-carbon steel long material is a pickling method shelling user or a mechanical method shelling user.

According to one embodiment of the invention, the laying temperature selected when the target user of the high carbon steel long product is an acid pickling shelling user is less than the laying temperature selected when the target user of the high carbon steel long product is a mechanical shelling user.

According to one embodiment of the invention, when the target user of the high-carbon steel long material is an acid pickling method husking user, the spinning temperature is controlled to be 840 +/-10 ℃; when the target user of the high-carbon steel long material is a mechanical shelling user, the spinning temperature is controlled to be 920 +/-10 ℃.

According to one embodiment of the invention, the spinning temperature is controlled by controlling the finish rolling outlet temperature and the water volume and water pressure at the inlet of the finish rolling water tank.

According to one embodiment of the invention, the cooling rate range of the slow cooling stage selected when the target user of the long high carbon steel product is a pickling process shelling user is different from the cooling rate range of the slow cooling stage selected when the target user of the long high carbon steel product is a mechanical process shelling user.

According to one embodiment of the invention, when the target user of the high-carbon steel long material is the acid pickling method shelling user, the slow cooling stage long material surface cooling rate is 2.0 ℃/s-3.0 ℃/s, and when the target user of the high-carbon steel long material is the mechanical method shelling user, the slow cooling stage long material surface cooling rate is 1.0 ℃/s-1.5 ℃/s.

According to one embodiment of the present invention, the cooling rate range of the quenching stage selected when the target user of the high-carbon steel long product is the pickling-method peeling user is the same as the cooling rate range of the quenching stage selected when the target user of the high-carbon steel long product is the mechanical-method peeling user.

According to one embodiment of the present invention, the cooling rate range of the quenching stage selected when the target user of the high-carbon steel long material is the pickling-method peeling user and the cooling rate range of the quenching stage selected when the target user of the high-carbon steel long material is the mechanical-method peeling user are both equal to or greater than 8.0 ℃/s.

According to one embodiment of the invention, the cooling speed is controlled by controlling the opening degree of the fan, the opening/closing of the heat-insulating cover and the speed of the rollerTo realize the operation; in the quenching stage, the corresponding fan opening degree is 100%, and the air quantity is 20 ten thousand m³The corresponding heat preservation cover is completely opened; in the slow cooling stage, the opening degree of the corresponding fan is 0%, when the target user of the high-carbon steel long material is a pickling method shelling user, the corresponding heat-insulating cover is completely opened, and when the target user of the high-carbon steel long material is a mechanical method shelling user, the corresponding heat-insulating cover is completely closed.

According to one embodiment of the invention, when the target user of the high-carbon steel long material is the pickling method shelling user, the bundling temperature is controlled to be 350 +/-10 ℃; when the target user of the high-carbon steel long material is a mechanical shelling user, the bundling temperature is controlled to be 450 +/-10 ℃.

The technical scheme of the invention controls the spinning temperature, the cooling speed (the opening degree of a fan, the opening/closing of a heat preservation cover and the roller speed) and the coiling temperature of a stelmor air-cooled line, so that the surface oxide of the high-carbon steel long material provided by a mechanical shelling user can fall off in a massive shape and the surface is smooth after falling off, the surface oxide of the high-carbon steel long material provided by an acid pickling shelling user is easy to acid pickle, and the oxide layer is thin.

The typical microstructure of the oxide layer on the surface of the high-carbon steel long material is divided into three layers: the outermost layer is Fe₂O₃The layer is very small in quantity, and the influence on the stripping performance of the oxide is ignored; the intermediate layer is pro-eutectoid Fe₃O₄A layer; the inner layer is a loose FeO layer. Under the common coupling of the three factors, the forming condition of the oxide can be finely controlled, the structure, the thickness and the performance of the oxide are changed, and the prepared oxide can meet the individual requirements.

The beneficial effects produced by adopting the technical scheme comprise:

(1) the temperature of the long material is uniform by controlling the temperature of a finish rolling outlet and the water quantity and the water pressure of an inlet of a water tank after finish rolling, the forming rate of oxides is reduced, and the surface quality of the long material matrix is improved;

(2) controlling the spinning temperature to obtain different thicknessesOxide layer with high phase content, mainly FeO, to co-precipitate Fe₃O₄Assisted by avoiding the generation of proeutectoid Fe which is difficult to remove₃O₄The proportion of FeO oxide which is easy to remove is improved;

(3) the spinning temperature selected when the target user is the acid pickling method husking user is controlled to be lower than the spinning temperature selected when the target user is the mechanical method husking user, so that a thin oxide layer with high FeO content is obtained, and the acid consumption of the acid pickling user is reduced.

(4) The cold speed from the spinning temperature to the phase transition temperature is controlled, the precipitation of eutectoid cementite in a high-carbon steel structure is avoided, and the structure and the performance of a high-carbon steel long material are effectively controlled;

(5) reasonably controlling the cooling speed from the phase transition temperature to the coiling temperature, and effectively controlling Fe precipitation in FeO oxide₃O₄The low cooling speed in the phase change process can ensure that the long material has sufficient phase change time to complete phase change, and the structure and the performance of the long material are effectively controlled;

(6) the slow cooling stage cooling speed from the phase transition temperature to the coil collecting temperature when the target user is the acid pickling method husking user is controlled to be different from the slow cooling stage cooling speed from the phase transition temperature to the coil collecting temperature when the target user is the mechanical method husking user, so that the eutectoid Fe is controlled₃O₄The content of Fe in FeO layer is such that Fe is not substantially precipitated from oxide when the oxide is used for peeling by pickling₃O₄When the user is mechanically husked, a certain amount of dispersed Fe is separated out from the oxide in the FeO layer₃O₄。

(7) When the target user of the high-carbon steel long material is the acid pickling method shelling user, the surface cooling rate of the long material in the slow cooling stage is 2.0 ℃/s-3.0 ℃/s, and Fe is basically not precipitated from an FeO layer in the cooling rate range₃O₄When the cooling rate is too low, Fe begins to be precipitated₃O₄And the too high cooling speed causes the problems of too large residual stress after the phase change process, incomplete structure transformation and the like.

(8) When the target user of the high-carbon steel long material is a mechanical shelling user, the surface cooling rate of the long material in the slow cooling stage is 1.0-1.5 ℃/s, and the FeO layer is in the cooling rate rangeCan separate out a certain amount of dispersed Fe₃O₄Excessive Fe will be precipitated when the cooling rate is too low₃O₄Attached to a long material matrix, influences the subsequent shelling effect, and does not precipitate dispersed Fe when the cooling speed is too high₃O₄。

(9) By the process control of the invention, the mass fraction of the acid-washing type oxide (namely, the mass of the oxide accounts for the total mass of the high-carbon steel long material) is controlled to be 0.4-0.5 percent, the content of FeO phase is more than 60 percent, and the acid consumption of the acid-washing method is reduced; through the process control of the invention, the mass fraction of the mechanically-shelled oxide is controlled to be 0.5-0.6%, and Fe₃O₄The phase content is more than 40 percent, so that granular Fe is eutectoid₃O₄A certain amount of the high-carbon steel is separated out, the integral strength of an oxide layer is increased, the high-carbon steel is prevented from falling off in the storage and transportation processes, and the obtained high-carbon steel meets the requirements of users in terms of structure and performance.

Detailed Description

In order to make the objects, technical solutions and advantages of the present invention more apparent, the present invention is described in further detail below with reference to specific embodiments. It should be understood that the specific embodiments described herein are merely illustrative of the invention and are not intended to limit the invention.

As required, detailed embodiments of the present invention are disclosed in the present specification; however, it is to be understood that the disclosed embodiments are merely exemplary of the invention that may be embodied in various and alternative forms. In the following description, various operating parameters and components are described in various embodiments as contemplated. These specific parameters and components are used in this specification as examples only and are not meant to be limiting.

The invention provides a stelmor method-based control method for surface oxides of high-carbon steel long materials, which is characterized in that the surface oxides of the high-carbon steel long materials provided by a mechanical shelling user drop in a massive manner and the surface is smooth after dropping through controlling the stelmor air-cooled line spinning temperature, the cooling speed (the opening degree of a fan, the opening/closing of a heat-preservation cover and the roller speed) and the coil collecting temperature, so that the surface oxides of the high-carbon steel long materials provided by a pickling method shelling user are easy to pickle and the oxide layer is thin.

The stelmor air-cooled line spinning temperature control comprises the following steps: for high-carbon steel long materials provided by users who peel by an acid pickling method, the spinning temperature is controlled to be 840 +/-10 ℃ by controlling the outlet temperature of finish rolling and the water quantity and water pressure of the inlet of a finish-rolled water tank; for high-carbon steel long products provided by a mechanical shelling user, the spinning temperature is controlled to be 920 +/-10 ℃ by controlling the outlet temperature of finish rolling and the water quantity and water pressure of the inlet of a water tank after finish rolling.

For high-carbon steel long products provided by users for shelling by an acid pickling method, the stelmor air-cooled linear cooling speed control comprises the following steps: the high-carbon steel long material obtained by spinning is cooled in two-stage and subsection manner, the first stage is from the spinning temperature of 840 +/-10 ℃ to the phase transition temperature of 590 +/-10 ℃, the corresponding opening degree of a fan is 100 percent, and the air volume is 20 ten thousand meters³And h, fully opening the corresponding heat-preservation cover to ensure that the surface cooling speed of the long material is more than or equal to 8.0 ℃/s, in the second stage, the phase transition temperature is 590 +/-10 ℃ to the coiling temperature is 350 +/-10 ℃, the corresponding opening degree of the fan is 0%, fully opening the corresponding heat-preservation cover to ensure that the surface cooling speed of the long material is 2.0 ℃/s-3.0 ℃/s, and thus obtaining the high-carbon steel long material surface metal oxide suitable for pickling.

For high carbon steel long products provided for mechanical shelling users, stelmor air-cooled line cooling rate control comprises: the high-carbon steel long material obtained by spinning is cooled in two-stage and subsection manner, the first stage is from the spinning temperature of 920 +/-10 ℃ to the phase transition temperature of 590 +/-10 ℃, the corresponding opening degree of a fan is 100 percent, and the air quantity is 20 ten thousand meters³And h, fully opening the corresponding heat-preservation cover to ensure that the surface cooling speed of the long material is more than or equal to 8.0 ℃/s, the phase transition temperature of the second section is 590 +/-10 ℃ to the coiling temperature of 450 +/-10 ℃, the opening degree of the corresponding fan is 0 percent, fully closing the corresponding heat-preservation cover to ensure that the surface cooling speed of the long material is 1.0 ℃/s-1.5 ℃/s, and thus obtaining the high-carbon steel long material surface metal oxide suitable for mechanical shelling.

In some embodiments, the high carbon steel is a SWRH82B long stock.

The surface of the high-carbon steel long material produced by the method can meet the individual requirements of a pickling method husking user/a mechanical method husking user, has wide coverage, and can be popularized and applied to control of oxides on the surfaces of other high-carbon ordinary steel long materials.

The present invention will be specifically described below with reference to specific examples.

Example 1

A certain metal product company adopts the technology to prepare hot-rolled long material raw materials for SWRH82B steel strands with the specification of phi 12.5mm, a target user adopts a mechanical method shelling process, and a stelmor method surface oxide control process comprises the following steps:

(1) controlling the outlet temperature of the finish rolling and the water quantity and the water pressure of the inlet of the water tank after the finish rolling, controlling the spinning temperature at 923 ℃, cooling the spun yarn in a stelmor air cooling line, and oxidizing the surface of the spun yarn to obtain thicker metal oxide mainly containing FeO;

(2) the first stage controls the opening degree of the 1# -4# fan, the opening value is 100%, and the air quantity is 20 ten thousand m³H, controlling the cooling speed from the spinning temperature to the phase transition temperature of 585 ℃ to 8.4 ℃/s to avoid precipitating eutectoid cementite in the tissue, entering a heat preservation cover when the second-stage phase transition temperature is 585 ℃, completely closing the heat preservation cover corresponding to the cooling section from the phase transition temperature to the coiling temperature of 452 ℃, controlling the opening degree of a fan to be 0 percent, controlling the cooling speed of the surface of the long material to be 1.2 ℃/s, and ensuring that granular eutectoid Fe is precipitated in an FeO layer₃O₄Increasing the overall strength of the oxide layer;

(3) the surface oxide mass fraction obtained was 0.54%, Fe₃O₄The phase content is 42%, the sorbite rate of the long material tissue is 90%, abnormal tissue is avoided, the average value of the tensile strength is 1185MPa, the average value of the reduction of area is 35%, oxides in a large block shape fall off in the user drawing process, the surface is smooth, the drawing lubricating powder is easy to hang and cover, and the drawing process is smooth.

Example 2

A certain metal product company adopts the technology to prepare hot-rolled long material raw materials for SWRH82B steel strands with the specification of phi 12.5mm, a target user adopts a mechanical method shelling process, and a stelmor method surface oxide control process comprises the following steps:

(1) controlling the outlet temperature of the finish rolling and the water quantity and the water pressure of the inlet of the water tank after the finish rolling, controlling the spinning temperature at 930 ℃, cooling the spun yarn in a stelmor air cooling line, and oxidizing the surface to obtain a thicker metal oxide mainly containing FeO;

(2) the first stage controls the opening degree of the 1# -4# fan, the opening value is 100%, and the air quantity is 20 ten thousand m³H, controlling the cooling rate from the spinning temperature to the phase transition temperature of 580 ℃ to be 8.7 ℃/s to avoid precipitating eutectoid cementite in the tissue, entering the heat-preservation cover when the phase transition temperature of the second section is 580 ℃, completely closing the heat-preservation cover corresponding to the cooling section from the phase transition temperature to the coiling temperature of 460 ℃, ensuring that the granular eutectoid Fe is precipitated in the FeO layer, wherein the opening degree of a fan is 0 percent, and the cooling rate of the surface of the long material is 1.0 ℃/s₃O₄Increasing the overall strength of the oxide layer;

(3) the surface oxide mass fraction obtained was 0.60%, Fe₃O₄The phase content is 45%, the sorbite rate of the long material tissue is 92%, abnormal tissues are avoided, the average value of the tensile strength is 1188MPa, the average value of the reduction of area is 36%, oxides in a large block shape fall off in the user drawing process, the surface is smooth, the drawing lubricating powder is easy to hang and cover, and the drawing process is smooth.

Example 3

A certain metal product company adopts the technology to prepare hot-rolled long material raw materials for SWRH82B steel strands with the specification of phi 12.5mm, a target user adopts a mechanical method shelling process, and a stelmor method surface oxide control process comprises the following steps:

(1) controlling the outlet temperature of the finish rolling and the water quantity and the water pressure of the inlet of the water tank after the finish rolling, controlling the spinning temperature at 910 ℃, cooling the spun yarn in a stelmor air cooling line, and oxidizing the surface to obtain a thicker metal oxide mainly containing FeO;

(2) the first stage controls the opening degree of the 1# -4# fan, the opening value is 100%, and the air quantity is 20 ten thousand m³H, controlling the cooling rate from the spinning temperature to the phase transition temperature of 600 ℃ to 8.0 ℃/s to avoid precipitating eutectoid cementite in the tissue, entering a heat-preserving cover when the phase transition temperature of the second section is 600 ℃, completely closing the heat-preserving cover corresponding to the cooling section from the phase transition temperature to the coiling temperature of 440 ℃, ensuring that FeO is converted into granular eutectoid Fe, wherein the opening degree of a fan is 0 percent, and the cooling rate of the surface of the long material is 1.5 ℃/s₃O₄Increasing the overall strength of the oxide layer;

(3) surface oxide mass fraction obtained0.50% of Fe₃O₄The phase content is 41%, the sorbite rate of the long material tissue is 93%, abnormal tissues are avoided, the average value of the tensile strength is 1189MPa, the average value of the reduction of area is 38%, oxides in a large block shape fall off in the user drawing process, the surface is smooth, the drawing lubricating powder is easy to hang and cover, and the drawing process is smooth.

Example 4 (counterexample)

A certain metal product company adopts the technology to prepare hot-rolled long material raw materials for SWRH82B steel strands with the specification of phi 12.5mm, a target user adopts a mechanical method shelling process, and a stelmor method surface oxide control process comprises the following steps:

(1) controlling the outlet temperature of the finish rolling and the water quantity and the water pressure of the inlet of the water tank after the finish rolling, controlling the spinning temperature at 915 ℃, cooling the spun yarn in a stelmor air cooling line, and oxidizing the surface to obtain a thicker metal oxide mainly containing FeO;

(2) the first stage controls the opening degree of the 1# -4# fan, the opening value is 100%, and the air quantity is 20 ten thousand m³H, controlling the cooling speed from the spinning temperature to the phase transition temperature 586 ℃ to be 8.5 ℃/s, avoiding precipitating eutectoid cementite in the tissue, entering the heat-preservation cover when the second-stage phase transition temperature 586 ℃ is reached, completely closing the heat-preservation cover corresponding to the cooling section from the phase transition temperature to the coiling temperature 501 ℃, ensuring that FeO is converted into granular eutectoid Fe with the fan opening degree of 0 percent and the long material surface cooling speed of 0.8 ℃/s₃O₄Increasing the overall strength of the oxide layer;

(3) the surface oxide mass fraction obtained was 0.61%, Fe₃O₄47% of phase content, 91% of sorbite rate of long material tissue, no abnormal tissue, 1187MPa of tensile strength average value, 37% of reduction of area average value, large-block-shaped oxide falling off in user drawing process, but residual bluish Fe on surface₃O₄The iron sheet is not easy to be coated with drawing lubricant powder, and the mould loss in the drawing process is large.

Example 5

A certain metal product company adopts the technology to prepare hot-rolled long material raw materials for SWRH82B steel strands with the specification of phi 12.5mm, a target user adopts an acid pickling method shelling process, and a stelmor method surface oxide control process comprises the following steps:

(1) controlling the outlet temperature of the finish rolling and the water quantity and the water pressure of the inlet of the water tank after the finish rolling, controlling the spinning temperature at 840 ℃, cooling the spun yarn in a stelmor air cooling line, and oxidizing the surface to obtain a thin metal oxide mainly containing FeO;

(2) the first stage controls the opening degree of the 1# -4# fan, the opening value is 100%, and the air quantity is 20 ten thousand m³The cooling speed from the spinning temperature to the phase transition temperature is controlled to be 8.5 ℃/s, the eutectoid cementite is prevented from being separated out from the tissue, the heat-preservation cover corresponding to the cooling section from the phase transition temperature of the second section of 590 ℃ to the coiling temperature of 358 ℃ is completely opened, the opening degree of a fan is 0 percent, the cooling speed on the surface of the long material is 2.6 ℃/s, the excessive oxidation and thickening of the oxide layer on the surface of the long material are avoided, and the granular eutectoid Fe is prevented from being separated out₃O₄The precipitation of the oxide increases the acid consumption of a user, so that the proportion of FeO in the oxide layer is improved and the whole oxide layer is thinner;

(3) the mass fraction of the obtained surface oxide is controlled to be 0.43 percent, the content of FeO phase is 68 percent, the sorbite rate of the long material tissue is 88 percent, abnormal tissue is avoided, the average value of tensile strength is 1178MPa, the average value of reduction of area is 38 percent, the surface is smooth after a user washes the acid, the surface is smooth after phosphorization and boronization, the surface is smooth and uniform in slip form, and the drawing process is smooth.

Example 6

A certain metal product company adopts the technology to prepare hot-rolled long material raw materials for SWRH82B wire making with the specification of phi 8.0mm, the target user is an acid pickling method shelling process, and a stelmor method surface oxide control process comprises the following steps:

(1) controlling the outlet temperature of the finish rolling and the water quantity and the water pressure of the inlet of the water tank after the finish rolling, controlling the spinning temperature at 845 ℃, cooling the spun yarn in a stelmor air cooling line, and oxidizing the surface to obtain a thin metal oxide mainly containing FeO;

(2) the first stage controls the opening degree of the 1# -4# fan, the opening value is 100%, and the air quantity is 20 ten thousand m³H, controlling the cooling speed from the spinning temperature to the phase transition temperature of 588 ℃ to be 8.5 ℃/s, avoiding precipitating eutectoid cementite in the tissue, opening all heat-insulating covers corresponding to the cooling section from the second section of the phase transition temperature of 588 ℃ to the coiling temperature of 360 ℃, and starting a fanThe temperature is 0 percent, the surface cooling speed of the long material is 2.2 ℃/s, the excessive oxidation thickening of the oxide layer on the surface of the long material is avoided, and the granular co-precipitation Fe is avoided₃O₄The precipitation of the oxide increases the acid consumption of a user, so that the proportion of FeO in the oxide layer is improved and the whole oxide layer is thinner;

(3) the mass fraction of the obtained surface oxide is controlled to be 0.46 percent, the content of FeO phase is 65 percent, the sorbite rate of the long material tissue is 92 percent, abnormal tissue is avoided, the average value of the tensile strength is 1201MPa, the average value of the reduction of area is 42 percent, the surface of the product is smooth after the product is pickled in the drawing process of a user, the surface of the product is smooth after phosphating and boronizing, and the product has uniform lubricating and sliding modes, and the drawing process is smooth.

Example 7

A certain metal product company adopts the technology to prepare hot-rolled long material raw materials for SWRH82B wire making with the specification of phi 12.5mm, the target user is an acid pickling method shelling process, and a stelmor method surface oxide control process comprises the following steps:

(1) controlling the outlet temperature of the finish rolling and the water quantity and the water pressure of the inlet of the water tank after the finish rolling, controlling the spinning temperature at 830 ℃, cooling the spun yarn in a stelmor air cooling line, and oxidizing the surface to obtain a thin metal oxide mainly containing FeO;

(2) the first stage controls the opening degree of the 1# -4# fan, the opening value is 100%, and the air quantity is 20 ten thousand m³The cooling speed from the spinning temperature to the phase transition temperature of 600 ℃ is controlled to be 8.3 ℃/s, the precipitation of proeutectoid cementite in the tissue is avoided, the heat-preservation cover corresponding to the cooling section from the second section of phase transition temperature of 600 ℃ to the coiling temperature of 340 ℃ is completely opened, the opening degree of a fan is 0 percent, the surface cooling speed of the long material is 3.0 ℃/s, the excessive oxidation and thickening of the oxide layer on the surface of the long material are avoided, and the granular eutectoid Fe is avoided₃O₄The precipitation of the oxide increases the acid consumption of a user, so that the proportion of FeO in the oxide layer is improved and the whole oxide layer is thinner;

(3) the mass fraction of the obtained surface oxide is controlled to be 0.40%, the content of FeO phase is 66%, the sorbite rate of the long material tissue is 94%, abnormal tissue is avoided, the average value of tensile strength is 1204MPa, the average value of reduction of area is 40%, the surface of the product is smooth after the product is pickled in the drawing process of a user, the surface of the product is smooth after phosphating and boronizing, the product is uniform in surface lubricating and sliding mode, and the drawing process is smooth.

Example 8

A certain metal product company adopts the technology to prepare hot-rolled long material raw materials for SWRH82B wire making with the specification of phi 12.5mm, the target user is an acid pickling method shelling process, and a stelmor method surface oxide control process comprises the following steps:

(1) controlling the outlet temperature of the finish rolling and the water quantity and the water pressure of the inlet of the water tank after the finish rolling, controlling the spinning temperature at 850 ℃, cooling the spun yarn in a stelmor air cooling line, and oxidizing the surface to obtain a thin metal oxide mainly containing FeO;

(2) the first stage controls the opening degree of the 1# -4# fan, the opening value is 100%, and the air quantity is 20 ten thousand m³The cooling speed from the spinning temperature to the phase transition temperature of 580 ℃ is controlled to be 8.5 ℃/s, the precipitation of proeutectoid cementite in the tissue is avoided, the heat-preservation cover corresponding to the cooling section from the second section of phase transition temperature of 580 ℃ to the coiling temperature of 360 ℃ is completely opened, the opening degree of a fan is 0 percent, the cooling speed on the surface of the long material is 2.0 ℃/s, the excessive oxidation and thickening of the oxide layer on the surface of the long material is avoided, and the particle-shaped eutectoid Fe is avoided₃O₄The precipitation of the oxide increases the acid consumption of a user, so that the proportion of FeO in the oxide layer is improved and the whole oxide layer is thinner;

(3) the mass fraction of the obtained surface oxide is controlled to be 0.50%, the FeO phase content is 61%, the sorbite rate of the long material tissue is 97%, abnormal tissue is avoided, the average value of the tensile strength is 1192MPa, the average value of the reduction of area is 41%, the surface of the product is smooth after the product is pickled in the drawing process of a user, the surface of the product is smooth after phosphating and boronizing, the sliding mode of the surface is uniform, and the drawing process is smooth.

It should be understood that although the steps of such methods, etc., are described as occurring in a certain order, such methods may perform operations using the described steps which are performed in an order other than the order described herein. It is further understood that certain steps may be performed simultaneously, that other steps may be added, or that certain steps described herein may be omitted. In other words, the description of the methods herein is provided for the purpose of illustrating certain embodiments and should not be construed as limiting the claimed invention in any way.

The above-described embodiments, particularly any "preferred" embodiments, are possible examples of implementations, and are presented merely for a clear understanding of the principles of the invention. Many variations and modifications may be made to the above-described embodiments without departing substantially from the spirit and principles of the technology described herein. All such modifications are intended to be included within the scope of this disclosure.