Wire isothermal heat treatment test device and test method

Abstract

This invention discloses a test apparatus and method for isothermal heat treatment of wire rods. The test apparatus includes a loading rack, a heating furnace, a salt bath, and a robotic arm. The loading rack is used to place the wire rods to be heat treated; the heating furnace is used to heat the wire rods; the salt bath includes an upper salt tank and a first lower salt tank and a second lower salt tank located below the upper salt tank. A first heater in the first lower salt tank is used to heat the molten salt inside to a second set temperature, and a second heater in the second lower salt tank is used to heat the molten salt inside to a third set temperature. The second and third set temperatures are different. The first lower salt tank and the upper salt tank are circulatedly connected through a first conveying component, and the second lower salt tank and the upper salt tank are circulatedly connected through a second conveying component. A bracket is provided in the upper salt tank. The robotic arm is used to transfer the wire rods between the heating furnace, the bracket, and the loading rack. This invention can simulate the isothermal heat treatment process of salt bath under different molten salt flow fields and can also carry out graded isothermal heat treatment tests.

Description

Technical Field

[0001] This invention relates to the field of heat treatment technology, specifically to a test apparatus and test method for isothermal heat treatment of wire. Background Technology

[0002] Isothermal heat treatment of wire is a heat treatment technology for metallic materials. Specifically, the wire is first heated to a fully austenitic state, and then quickly quenched in a molten salt bath or lead bath, so that the wire undergoes a phase transformation under near-isothermal conditions to obtain ideal microstructure and properties.

[0003] With increasing environmental awareness, isothermal heat treatment of wire rods using molten salt baths has become a mainstream method. Experimental research is an important means of developing new isothermal heat treatment processes using salt baths, which can verify the feasibility of the process at a lower cost and conduct basic research. Currently, salt bath experiments mostly use single-temperature salt bath furnaces as experimental equipment, and the wire rods are subjected to isothermal heat treatment in the salt bath by spraying. This method is difficult to simulate the isothermal heat treatment process under different molten salt flow fields, and it is also not easy to carry out staged isothermal heat treatment experiments. Summary of the Invention

[0004] In view of this, the present invention provides a wire isothermal heat treatment test device and test method to solve the problems that existing salt bath isothermal heat treatment test equipment is difficult to simulate the salt bath isothermal heat treatment process under different molten salt flow fields and is not easy to carry out graded salt bath isothermal heat treatment tests.

[0005] In a first aspect, the present invention provides a wire isothermal heat treatment test apparatus, comprising: The feeding rack has a first bearing area for placing wire rods to be heat-treated; A heating furnace, which has an internal working state that forms a reducing atmosphere, is used to heat wire rod to a first set temperature; A salt bath includes an upper salt tank and a first lower salt tank and a second lower salt tank located below the upper salt tank. A first heater is installed in the first lower salt tank to heat the molten salt in the first lower salt tank to a second set temperature. A second heater is installed in the second lower salt tank to heat the molten salt in the second lower salt tank to a third set temperature. The first set temperature is greater than the second set temperature and also greater than the third set temperature. The second set temperature and the third set temperature are set to be different. The first lower salt tank and the upper salt tank are circulatedly connected via a first conveying component, and the second lower salt tank and the upper salt tank are circulatedly connected via a second conveying component. The bracket is installed inside the upper salt tank; A robotic arm is used to transfer wire rods located in the first bearing area to the interior of the heating furnace, and to transfer wire rods located inside the heating furnace to the bracket.

[0006] The isothermal heat treatment test apparatus for wires according to the present invention has at least the following beneficial effects: The system comprises two independent lower salt tanks, a first lower salt tank and a second lower salt tank, located below the upper salt tank. The first lower salt tank contains molten salt at a second set temperature, and the second lower salt tank contains molten salt at a third set temperature. The first lower salt tank is circulated with the upper salt tank via a first conveying component, and the second lower salt tank is circulated with the upper salt tank via a second conveying component. During the isothermal heat treatment test of the wire rod, a robotic arm is first controlled to transfer the wire rod to be heat-treated into a heating furnace for heating. After heating, the robotic arm is controlled to transfer the wire rod from the heating furnace to a support. Subsequently, the first conveying component is controlled to circulate the molten salt at the second set temperature between the first lower salt tank and the upper salt tank. At this time, the wire rod located on the support is immersed in the molten salt. The first stage of isothermal heat treatment is performed on molten salt at a dynamic second set temperature. After the first stage of isothermal heat treatment is completed, the first conveying component is stopped, and the second conveying component is controlled to circulate molten salt at a third set temperature between the second lower salt tank and the upper salt tank. At this time, the wire rod that has just completed the first stage of isothermal heat treatment is immersed in molten salt at a dynamic third set temperature for the second stage of isothermal heat treatment. This allows for the simulation of salt bath isothermal heat treatment processes under different molten salt flow fields in the same experimental device, and also enables the conduct of graded salt bath isothermal heat treatment experiments. This helps to study the impact of graded salt bath heat treatment processes and molten salt flow fields on the properties of steel, thereby accelerating the research and development of new salt bath isothermal heat treatment processes.

[0007] In one optional embodiment, the upper salt tank has a salt inlet pipe connected to one side in the horizontal direction, and an overflow trough is provided on the outside of the first sidewall of the upper salt tank. The top of the first sidewall is lower than the top of the other sidewalls of the upper salt tank. The first lower salt tank has a first inlet that is connected to the overflow trough. The first inlet is controlled to open or close by a first control component. The first conveying component includes: The first salt inlet pipe has one end connected to the interior of the first lower salt tank and the other end connected to the salt inlet pipe; The first molten salt pump is installed on the first salt inlet pipe.

[0008] In one optional embodiment, the second lower salt tank is provided with a second inlet, which communicates with the overflow tank, and the second inlet is controlled to open or close by a second control component; the second conveying component includes: The second salt inlet pipe has one end connected to the interior of the second lower salt tank and the other end connected to the salt inlet pipe; The second molten salt pump is installed on the second salt inlet pipe.

[0009] In one alternative embodiment, the first molten salt pump drives molten salt to flow in the first salt inlet pipe at a first flow rate, and the second molten salt pump drives molten salt to flow in the second salt inlet pipe at a second flow rate, wherein the first flow rate and the second flow rate are set to be different.

[0010] In one alternative embodiment, the second control component includes a second plug and a second drive, the second plug having a first state in which it is driven by the second drive to move closer to the second inlet and block the second inlet, and a second state in which it is driven by the second drive to move away from the second inlet and open the second inlet.

[0011] In one optional embodiment, the second conveying assembly further includes a second three-way valve, the first port of which is connected to the second salt inlet pipe, the second port of which is connected to the salt inlet pipe, and the third port of which is connected to a second return pipe, the second return pipe communicating with the interior of the second lower salt tank.

[0012] In one alternative embodiment, the first control component includes a first plug and a first drive, the first plug having a third state in which it is driven by the first drive to move closer to the first inlet and block the first inlet, and a fourth state in which it is driven by the first drive to move away from the first inlet and open the first inlet.

[0013] In one optional embodiment, the first conveying assembly further includes a first three-way valve, the first port of the first three-way valve being connected to the first salt inlet pipe, the second port of the first three-way valve being connected to the salt inlet pipe, and the third port of the first three-way valve being connected to a first return pipe, the first return pipe being in communication with the interior of the first lower salt tank.

[0014] In one alternative embodiment, one of a plurality of baffles of different heights is detachably installed in the upper salt tank and serves as the first sidewall, and the projection of the bracket and the bar located on the bracket in the horizontal direction falls within the range of the baffle.

[0015] In one alternative embodiment, the top of the loading rack also has a second bearing area for placing heat-treated wire rods, and the robot arm is also used to transfer the wire rods located on the bracket to the second bearing area.

[0016] In one alternative embodiment, the wire rod is in a straightened state, and the top of the bracket has a groove for positioning and supporting the wire rod.

[0017] Secondly, the present invention also provides a testing method applied to the wire isothermal heat treatment testing apparatus provided in the first aspect above, the testing method comprising the following steps: The wire rods to be heat-treated are placed in the first bearing area according to the set distribution pattern; The internal temperature of the heating furnace is controlled to rise to a first set temperature, and the molten salt in the first lower salt tank is heated to a second set temperature, and the molten salt in the second lower salt tank is heated to a third set temperature; The robotic arm is controlled to transfer the wire rod located in the first bearing area into the heating furnace; After the heating furnace finishes heating the wire rod, the robotic arm is controlled to transfer the wire rod located in the heating furnace to the bracket; The first conveying component is controlled to circulate molten salt at a second set temperature between the first lower salt tank and the upper salt tank, so that the wire rod located on the bracket is immersed in the molten salt at the second set temperature for the first stage of isothermal heat treatment. After the first stage of isothermal heat treatment is completed, the first conveying component is stopped, and the second conveying component is controlled to circulate the molten salt at the third set temperature between the second lower salt tank and the upper salt tank, so that the wire rod located on the bracket is immersed in the molten salt at the third set temperature for the second stage of isothermal heat treatment. After the second stage of isothermal heat treatment is completed, the second conveying component is stopped, and the robotic arm is controlled to remove the wire rod located on the bracket.

[0018] According to a test method of the present invention, at least the following beneficial effects are achieved: The system comprises two independent lower salt tanks, a first lower salt tank and a second lower salt tank, located below the upper salt tank. The first lower salt tank is circulated with the upper salt tank via a first conveying component, and the second lower salt tank is circulated with the upper salt tank via a second conveying component. During the isothermal heat treatment test of the wire rod, a robotic arm is first controlled to transfer the wire rod to be heat-treated into a heating furnace for heating. Simultaneously, a first heater is controlled to heat the molten salt in the first lower salt tank to a second set temperature, and a second heater is controlled to heat the molten salt in the second lower salt tank to a third set temperature. After the wire rod is heated in the heating furnace, the robotic arm is controlled to transfer the wire rod from the heating furnace to a support. Then, the first conveying component is controlled to circulate the molten salt at the second set temperature between the first lower salt tank and the upper salt tank. At this point, the wire rod located on the bracket is immersed in molten salt at a dynamic and second set temperature for the first stage of isothermal heat treatment. After the first stage of isothermal heat treatment is completed, the first conveying component is stopped, and the second conveying component is controlled to circulate molten salt at a third set temperature between the second lower salt tank and the upper salt tank. At this point, the wire rod that has just completed the first stage of isothermal heat treatment is immersed in molten salt at a dynamic and third set temperature for the second stage of isothermal heat treatment. This allows for the simulation of salt bath isothermal heat treatment processes under different molten salt flow fields in the same experimental device, and also enables the conduct of graded salt bath isothermal heat treatment experiments. This helps to study the effects of graded salt bath heat treatment processes and molten salt flow fields on the properties of steel, thereby accelerating the research and development of new salt bath isothermal heat treatment processes. Attached Figure Description

[0019] To more clearly illustrate the specific embodiments of the present invention or the technical solutions in the prior art, the drawings used in the description of the specific embodiments or the prior art will be briefly introduced below. Obviously, the drawings described below are some embodiments of the present invention. For those skilled in the art, other drawings can be obtained from these drawings without creative effort.

[0020] Figure 1 This is a schematic diagram of the main structure of an embodiment of the present invention; Figure 2 This is a top view of the structure according to an embodiment of the present invention; Figure 3 This is a side view of a portion of the structure in an embodiment of the present invention.

[0021] Explanation of reference numerals in the attached figures: 100 - Loading rack, 110 - First load-bearing area, 120 - Second load-bearing area; 200-Heating furnace, 210-Furnace body, 211-First inlet, 212-Second inlet, 213-Furnace opening, 220-Heating wire, 230-First lifting mechanism, 240-Furnace door, 250-Temperature measuring thermocouple; 300-Salt bath tank, 310-Upper salt tank, 311-Salt inlet pipe, 312-Overflow tank, 313-Baffle, 320-First lower salt tank, 321-First heater, 322-First inlet, 330-Second lower salt tank, 331-Second heater, 332-Second inlet; 400-Bracket; 500-Robotic arm, 510-Rotating base, 520-Actuating arm, 530-Gripper, 540-High temperature resistant gripper; 610 - First salt inlet pipe, 620 - First molten salt pump, 630 - First three-way valve; 710 - Second salt inlet pipe, 720 - Second molten salt pump, 730 - Second three-way valve; 810 - Second piston section, 820 - Second drive section; 910 - First Plug Section, 920 - First Drive Section; 1000-wire rod. Detailed Implementation

[0022] To make the objectives, technical solutions, and advantages of the embodiments of the present invention clearer, the technical solutions of the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of the present invention, not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of the present invention.

[0023] In the description of this embodiment, it should be noted that the terms "center," "upper," "lower," "left," "right," "vertical," "horizontal," "inner," and "outer," etc., indicate the orientation or positional relationship based on the orientation or positional relationship shown in the accompanying drawings. They are only for the convenience of describing this embodiment and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation. Therefore, they should not be construed as limitations on this embodiment. In addition, the terms "first," "second," and "third" are used for descriptive purposes only and should not be construed as indicating or implying relative importance.

[0024] In the description of this embodiment, it should be noted that, unless otherwise explicitly specified and limited, the terms "installation," "connection," and "linking" should be interpreted broadly. For example, they can refer to a fixed connection, a detachable connection, or an integral connection; they can refer to a mechanical connection or an electrical connection; they can refer to a direct connection or an indirect connection through an intermediate medium; and they can refer to the internal connection of two components. Those skilled in the art can understand the specific meaning of the above terms in this embodiment according to the specific circumstances.

[0025] The following is combined Figures 1 to 3 The following describes embodiments of the present invention.

[0026] According to a first aspect of the present invention, an isothermal heat treatment testing apparatus for wire is provided, comprising a loading rack 100, a heating furnace 200, a salt bath 300, and a robotic arm 500. The loading rack 100 has a first bearing area 110 for placing wire rods 1000 to be heat treated. The heating furnace 200 has an internal working state for forming a reducing atmosphere and is used to heat the wire rods 1000 to a first set temperature. The salt bath 300 includes an upper salt tank 310 and a first lower salt tank 320 and a second lower salt tank 330 located below the upper salt tank 310. A first heater 321 is disposed in the first lower salt tank 320 and is used to heat the molten salt in the first lower salt tank 320 to a second set temperature. A second heater 331 is provided in the lower salt tank 330. The second heater 331 is used to heat the molten salt in the second lower salt tank 330 to a third set temperature. The first set temperature is greater than the second set temperature, and the second set temperature is greater than the third set temperature. The second set temperature and the third set temperature are set to be different. The first lower salt tank 320 and the upper salt tank 310 are circulatedly connected through a first conveying component. The second lower salt tank 330 and the upper salt tank 310 are circulatedly connected through a second conveying component. A bracket 400 is provided in the upper salt tank 310. A robot arm 500 is used to transfer the wire rod 1000 located in the first bearing area 110 to the inside of the heating furnace 200, and to transfer the wire rod 1000 located inside the heating furnace 200 to the bracket 400.

[0027] The experimental apparatus of this embodiment has a first lower salt tank 320 and a second lower salt tank 330, which are independent of each other, located below the upper salt tank 310. The first lower salt tank 320 contains molten salt at a second set temperature, and the second lower salt tank 330 contains molten salt at a third set temperature. The first lower salt tank 320 is circulatedly connected to the upper salt tank 310 through a first conveying component, and the second lower salt tank 330 is circulatedly connected to the upper salt tank 310 through a second conveying component. During the isothermal heat treatment test on the wire rod 1000, the robot arm 500 is first controlled to transfer the wire rod 1000 to be heat-treated into the heating furnace 200 for heating. After heating is completed, the robot arm 500 is controlled to transfer the wire rod 1000 in the heating furnace 200 to the bracket 400. Then, the first conveying component is controlled so that the molten salt at the second set temperature is in the first lower salt tank 320. The molten salt flows between the upper salt tank 310 and the lower salt tank 330. At this time, the wire rod 1000 located on the bracket 400 is immersed in the dynamic molten salt at the second set temperature for the first stage of isothermal heat treatment. After the first stage of isothermal heat treatment is completed, the first conveying component is stopped, and the second conveying component is controlled to circulate the molten salt at the third set temperature between the lower salt tank 330 and the upper salt tank 310. At this time, the wire rod 1000, which has just completed the first stage of isothermal heat treatment, is immersed in the dynamic molten salt at the third set temperature for the second stage of isothermal heat treatment. This allows for the simulation of salt bath isothermal heat treatment processes under different molten salt flow fields in the same experimental device, and also enables the conduct of graded salt bath isothermal heat treatment experiments. This helps to study the effects of graded salt bath heat treatment processes and molten salt flow fields on the properties of steel, thereby accelerating the research and development of new salt bath isothermal heat treatment processes.

[0028] It should be noted that the first conveying component allows molten salt at a second set temperature to flow in the upper salt tank 310 at different flow rates, and the second conveying component allows molten salt at a third set temperature to flow in the upper salt tank 310 at different flow rates, thereby facilitating the simulation of the isothermal heat treatment process of the wire rod 1000 in different molten salt flow fields.

[0029] It should be noted that the first heater 321 can heat the molten salt contained in the first lower salt tank 320 to different second set temperatures, and the second heater 331 can heat the molten salt contained in the second lower salt tank 330 to different third set temperatures. This enables the adjustment of the molten salt temperature for the first stage of isothermal heat treatment and the adjustment of the molten salt temperature for the second stage of isothermal heat treatment. As a result, multiple graded salt bath isothermal heat treatment experiments can be carried out using the same experimental device under experimental conditions. Furthermore, the salt bath isothermal heat treatment process can be verified under laboratory conditions, thereby reducing the cost of developing new processes.

[0030] It should be noted that during the entire test, the robotic arm 500 automatically transferred the wire rod 1000 between the feeding rack 100, the heating furnace 200, and the bracket 400. This high level of automation reduced the intensity of manual labor and avoided test errors caused by manual operation.

[0031] It is understandable that during the heating process of the heating furnace 200 heating the wire rod 1000, the interior of the heating furnace 200 is in a state of forming a reducing atmosphere, which slows down the oxidation and decarburization of the wire rod 1000 when the heating furnace 200 heats it, thus providing a basic guarantee for obtaining good surface quality and stable mechanical properties.

[0032] It is understood that in this embodiment, the first lower salt tank 320 and the second lower salt tank 330 are independent of each other, and the molten salt circulation loop formed between the first lower salt tank 320 and the upper salt tank 310 and the molten salt circulation loop formed between the second lower salt tank 330 and the upper salt tank 310 are independent of each other, which can avoid the mutual interference between the first stage isothermal heat treatment and the second stage isothermal heat treatment.

[0033] In specific applications, the first set temperature is set to 800℃ to 1000℃, the second set temperature is set to 200℃ to 600℃, and the third set temperature is set to 200℃ to 600℃.

[0034] In practical applications, the second set temperature can be set higher than the third set temperature, or the second set temperature can be set lower than the third set temperature.

[0035] In specific applications, in some embodiments, the first lower salt tank 320 and the second lower salt tank 330 can hold molten salt of the same composition; in another embodiment, the first lower salt tank 320 and the second lower salt tank 330 can hold molten salt of different compositions respectively.

[0036] In specific applications, the molten salt component is one of nitrates, chlorides, or a mixture of both.

[0037] In specific applications, to improve the insulation effect and service life of the salt bath 300, the salt bath 300 is made of insulation material.

[0038] like Figure 1 and Figure 2As shown, specifically, the robotic arm 500 includes a rotating base 510, an actuator arm 520, a gripper 530, and a high-temperature resistant gripper 540. The actuator arm 520 is mounted on the rotating base 510 and is driven by a motor. The actuator arm 520 has a gripper 530 at its end, and the gripper 530 has a high-temperature resistant gripper 540 at the end opposite to the actuator arm. The high-temperature resistant gripper 540 is used to grip and transfer at least one wire rod 1000 at a time, preferably five wire rods at a time. The 1000 robotic arm 500 is equipped with a main controller that electrically connects to a rotating base 510, an execution arm 520, a gripper 530, a motor, and a high-temperature resistant gripper 540. It can realize the positioning and movement of the gripper 530 and the high-temperature resistant gripper 540, thereby realizing isothermal heat treatment of five wire rod 1000 samples at a time. The test efficiency is high, the sampling and loading actions are completely controlled by the program, and the time interval between the wire rod 1000 leaving the furnace and entering the salt bath is accurately controllable, avoiding test errors caused by manual operation.

[0039] like Figures 1 to 3 As shown, specifically, the wire rod 1000 is in a straightened state, and the top of the bracket 400 has a groove for positioning and supporting the wire rod 1000, which facilitates the precise positioning and placement of the straightened wire rod 1000. This ensures that the spacing between multiple straightened wire rods 1000 placed in the upper salt tank 310 is consistent, which helps to avoid test errors caused by manual operation.

[0040] like Figure 2 As shown, specifically, the top of the loading rack 100 also has a second bearing area 120 for placing the heat-treated wire rod 1000, and the robot arm 500 is also used to transfer the wire rod 1000 located on the bracket 400 to the second bearing area 120. With this arrangement, after the second stage of isothermal heat treatment is completed, the robot arm 500 can automatically transfer the heat-treated wire rod 1000 to the second bearing area 120, realizing the placement of both the wire rod 1000 to be heat-treated and the wire rod 1000 that has undergone heat treatment on the same loading rack 100, thus reducing the installation space occupied by the test device in this embodiment.

[0041] like Figure 1As shown, specifically, the heating furnace 200 includes a furnace body 210. An electric heating wire 220 is installed on the inner wall of the furnace body 210 to heat the wire rod 1000 placed inside the furnace body 210. A first inlet 211 is provided through the side wall of the furnace body 210, and a second inlet 212 is provided through the top of the furnace body 210. The first inlet 211 is used to inject inert gas into the furnace body 210, and the second inlet 212 is used to inject carburizing agent into the furnace body 210. By injecting carburizing agent into the furnace body 210, a reducing atmosphere is formed inside the furnace body 210. Inert gas can be introduced into the furnace body 210. By changing the amount of carburizing agent and inert gas added, the atmosphere inside the furnace body 210 is adjusted, ensuring that the heating furnace 200 slows down the oxidation and decarburization of the wire rod 1000 when heating it, providing a basic guarantee for obtaining good surface quality and stable mechanical properties.

[0042] like Figure 1 and Figure 2 As shown, specifically, a furnace opening 213 communicating with the interior of the furnace body 210 is provided on the side wall of the furnace body 210. A furnace door 240 driven by a first lifting mechanism 230 is provided on the furnace body 210 at the position corresponding to the furnace opening 213. The furnace door 240 has a fifth state in which it is driven by the first lifting mechanism 230 to move closer to the furnace opening 213 and block the furnace opening 213, and a sixth state in which it is driven by the first lifting mechanism 230 to move away from the furnace opening 213 and open the furnace opening 213. When it is necessary to transfer the wire rod 1000 to be heat-treated into the furnace body 210 and to remove the heated wire rod 1000 from the furnace body 210, the furnace door 240 is switched to the sixth state so that the robot arm 500 can pass through the furnace opening 213; when the heating wire 220 heats the wire rod 1000 located inside the furnace body 210, the furnace door 240 is switched to the fifth state to ensure that the heat is not easily diffused to the outside through the furnace opening 213, so that the temperature inside the furnace body 210 remains stable, thereby ensuring that the wire rod 1000 is heated to the first set temperature.

[0043] To more precisely control the heating accuracy of the furnace body 210 on the wire rod 1000, such as Figure 1 and Figure 2 As shown, specifically, a temperature measuring thermocouple 250 is installed inside the furnace body 210, which is used to measure the temperature of the hot air inside the furnace body 210.

[0044] To improve the insulation effect and service life of the furnace body 210, the furnace body 210 is specifically made of insulation material.

[0045] like Figure 1 and Figure 3As shown, in some embodiments, the upper salt tank 310 has a salt inlet pipe 311 connected to one side in the horizontal direction. An overflow trough 312 is provided outside the first sidewall of the upper salt tank 310. The top height of the first sidewall is lower than the top height of the other sidewalls of the upper salt tank 310. A first lower salt tank 320 has a through-hole first inlet 322 connected to the overflow trough 312. The first inlet 322 is controlled to open or close by a first control component. The first conveying component includes: The first salt inlet pipe 610 has one end connected to the interior of the first lower salt tank 320 and the other end connected to the salt inlet pipe 311; The first molten salt pump 620 is installed on the first salt inlet pipe 610.

[0046] The experimental apparatus of this embodiment sets the top height of the first sidewall of the upper salt tank 310 to be lower than the top height of the other sidewalls of the upper salt tank 310, and provides an overflow trough 312 outside the first sidewall. A first molten salt pump 620 is installed on the first salt inlet pipe 610. During the process of transferring the heated wire rod 1000 to the bracket 400 and performing the first stage of isothermal heat treatment on the wire rod 1000, the first inlet 322 is opened, and the first molten salt pump 620 is controlled to pump molten salt at a second set temperature sequentially from inside the first lower salt tank 320 through... The molten salt is transported to the upper salt tank 310 through the first salt inlet pipe 610 and the salt outlet pipe 311. After the liquid level of the molten salt accumulated in the upper salt tank 310 is higher than the top of the first side wall, it overflows into the overflow tank 312 and flows back to the first lower salt tank 320 through the first inlet 322. This achieves the circulation of molten salt at the second set temperature between the first lower salt tank 320 and the upper salt tank 310, so that the liquid level of the molten salt in the upper salt tank 310 is basically consistent with the top of the first side wall. This is beneficial to improving the isothermal heat treatment effect of the first stage of the wire rod 1000.

[0047] It is understandable that the first sidewall mentioned in the text refers to the sidewall of the upper salt tank 310 adjacent to the overflow tank 312.

[0048] It is understandable that the first sidewall is the sidewall of the upper salt tank 310 that is horizontally opposite to the salt inlet pipe 311.

[0049] like Figure 1 and Figure 3As shown, specifically, the first control component includes a first plug portion 910 and a first drive portion 920. The first plug portion 910 has a third state in which it is driven by the first drive portion 920 to move closer to and block the first inlet 322, and a fourth state in which it is driven by the first drive portion 920 to move away from and open the first inlet 322. By driving the first plug portion 910 to move closer to or away from the first inlet 322, the first drive portion 920 can automatically control the first plug portion 910 to switch between the third and fourth states, thereby achieving automatic control of opening or blocking the first inlet 322. This results in a high level of automation and reduces the intensity of manual labor.

[0050] In specific applications, the first drive unit 920 can be configured as a linear actuator such as an electric telescopic rod or a cylinder.

[0051] like Figures 1 to 3 As shown, specifically, the first conveying assembly also includes a first three-way valve 630. The first port of the first three-way valve 630 is connected to the first salt inlet pipe 610, the second port of the first three-way valve 630 is connected to the salt inlet pipe 311, and the third port of the first three-way valve 630 is connected to a first return pipe (not shown in the figure). The first return pipe communicates with the interior of the first lower salt tank 320. With this configuration, during the heating process of the wire rod 1000 located inside the heating furnace 200, the first port and the third port of the first three-way valve 630 are connected, allowing the molten salt at the second set temperature to circulate between the first salt inlet pipe 610, the first return pipe, and the first lower salt tank 320. This ensures that the first salt inlet pipe 610 is filled with molten salt. When the heated wire rod 1000 is transferred to the bracket 400 for the first stage of isothermal heat treatment, the first port and the second port of the first three-way valve 630 are connected, allowing the first salt inlet pipe 610, pre-filled with molten salt, to quickly introduce the molten salt into the upper salt tank 310, improving the response speed and enhancing the isothermal heat treatment effect on the wire rod 1000 in the first stage.

[0052] like Figure 1 and Figure 3 As shown, in some embodiments, a second inlet 332 is provided through the second lower salt tank 330, and the second inlet 332 is connected to the overflow tank 312. The second inlet 332 is controlled to open or close by a second control component; the second conveying component includes: The second salt inlet pipe 710 has one end connected to the interior of the second lower salt tank 330 and the other end connected to the salt inlet pipe 311; The second molten salt pump 720 is installed on the second salt inlet pipe 710.

[0053] The experimental apparatus of this embodiment sets the top height of the first sidewall of the upper salt tank 310 to be lower than the top height of the other sidewalls of the upper salt tank 310, and provides an overflow trough 312 outside the first sidewall. A second molten salt pump 720 is installed on the second salt inlet pipe 710. During the second stage of isothermal heat treatment of the wire rod 1000 on the bracket 400, the first inlet 322 is blocked while the second inlet 332 is opened, and the second molten salt pump 720 is controlled to pump molten salt at a third set temperature from inside the second lower salt tank 330 sequentially through... The molten salt is transported to the upper salt tank 310 through the second salt inlet pipe 710 and the salt inlet pipe 311. After the liquid level of the molten salt accumulated in the upper salt tank 310 is higher than the top of the first side wall, it overflows into the overflow tank 312 and flows back to the second lower salt tank 330 through the second inlet 332. This achieves the circulation of molten salt at the third set temperature between the second lower salt tank 330 and the upper salt tank 310, so that the liquid level of the molten salt in the upper salt tank 310 is basically consistent with the top of the first side wall. This is beneficial to improving the isothermal heat treatment effect of the second stage of the wire rod 1000.

[0054] Understandably, during the first stage of isothermal heat treatment, when the heated wire rod 1000 is transferred to the bracket 400, the first inlet 322 is opened and the second inlet 332 is blocked; during the second stage of isothermal heat treatment, when the wire rod 1000 that has completed the first stage of isothermal heat treatment is subjected to the second stage of isothermal heat treatment, the second inlet 332 is opened and the first inlet 322 is blocked, to ensure that the molten salt circulation loop formed between the first lower salt tank 320 and the upper salt tank 310 and the molten salt circulation loop formed between the second lower salt tank 330 and the upper salt tank 310 are independent of each other and do not interfere with each other.

[0055] It should be noted that, as Figure 2 As shown, in this embodiment, the molten salt circulation loop formed between the first lower salt tank 320 and the upper salt tank 310 and the molten salt circulation loop formed between the second lower salt tank 330 and the upper salt tank 310 share a salt inlet pipe 311 and an overflow tank 312, which helps to reduce the installation area occupied by this embodiment while achieving the function.

[0056] like Figure 1 and Figure 3As shown, specifically, the second control component includes a second plug portion 810 and a second drive portion 820. The second plug portion 810 has a first state in which it is driven by the second drive portion 820 to move closer to and block the second inlet 332, and a second state in which it is driven by the second drive portion 820 to move away from and open the second inlet 332. By driving the second plug portion 810 to move closer to or away from the second inlet 332, the second plug portion 810 can be automatically controlled to switch between the first and second states, thereby achieving automatic control of opening or blocking the second inlet 332. This results in a high level of automation and reduces manual labor intensity.

[0057] In specific applications, the second drive unit 820 can be configured as a linear actuator such as an electric telescopic rod or a cylinder.

[0058] like Figures 1 to 3 As shown, specifically, the second conveying assembly also includes a second three-way valve 730. The first port of the second three-way valve 730 is connected to the second salt inlet pipe 710, the second port of the second three-way valve 730 is connected to the salt inlet pipe 311, and the third port of the second three-way valve 730 is connected to a second return pipe (not shown in the figure). The second return pipe communicates with the interior of the second lower salt tank 330. With this configuration, during the first stage of isothermal heat treatment after the heated wire rod 1000 is transferred to the bracket 400, the first port and the third port of the second three-way valve 730 are connected, allowing the molten salt at the third set temperature to circulate between the second salt inlet pipe 710, the second return pipe, and the second lower salt tank 330. This ensures that the second salt inlet pipe 710 is filled with molten salt. When the wire rod 1000 undergoes the second stage of isothermal heat treatment, the first port and the second port of the second three-way valve 730 are connected, and the second salt inlet pipe 710, pre-filled with molten salt, can quickly introduce the molten salt into the upper salt tank 310, improving the response speed and enhancing the isothermal heat treatment effect on the wire rod 1000 in the second stage.

[0059] In some embodiments, a first molten salt pump 620 drives molten salt to flow in a first salt inlet pipe 610 at a first flow rate, and a second molten salt pump 720 drives molten salt to flow in a second salt inlet pipe 710 at a second flow rate, wherein the first and second flow rates are set to be different. Molten salt at a second set temperature is introduced into the upper salt bath 310 by the first molten salt pump 620 at a first flow rate to perform a first stage of isothermal heat treatment on the wire rod 1000; and molten salt at a third set temperature is introduced into the upper salt bath 310 by the second molten salt pump 720 at a second flow rate different from the first flow rate to perform a second stage of isothermal heat treatment on the wire rod 1000. This allows the wire rod 1000 undergoing the first stage of isothermal heat treatment and the wire rod 1000 undergoing the second stage of isothermal heat treatment to be in different molten salt flow fields, which helps to study the impact of graded salt bath heat treatment processes and molten salt flow fields on the properties of steel, thereby accelerating the development of new salt bath isothermal heat treatment processes.

[0060] In another alternative embodiment, a first molten salt pump 620 drives molten salt to flow in a first salt inlet pipe 610 at a first flow rate, and a second molten salt pump 720 drives molten salt to flow in a second salt inlet pipe 710 at a second flow rate, wherein the first flow rate and the second flow rate are set to be the same.

[0061] In some embodiments, one of a plurality of baffles 313 of different heights is detachably installed in the upper salt tank 310 as a first sidewall, and the horizontal projection of the bracket 400 and the wire rod 1000 located on the bracket 400 falls within the area of ​​the baffle 313. With this arrangement, during the test, baffles 313 of different heights can be selected to be installed in the upper salt tank 310 as the first sidewall, thereby adjusting the depth to which the wire rod 1000 located on the bracket 400 is immersed in the molten salt during the first stage and / or the second stage of isothermal heat treatment, thereby enabling the study of the effect of different molten salt liquid level depths on the cooling of the wire rod 1000 during isothermal heat treatment in the same test apparatus.

[0062] It should be noted that in this embodiment, the horizontal projection of the bracket 400 and the wire rod 1000 located on the bracket 400 falls within the range of the baffle 313. Therefore, regardless of the height and size of the baffle 313 used as the first sidewall, it can be ensured that the wire rod 1000 located on the bracket 400 is completely immersed in the molten salt, thereby ensuring the isothermal heat treatment effect.

[0063] In specific applications, the upper salt tank 310 is provided with slots on both sides of the baffle 313, and the two sides of the baffle 313 are respectively inserted into the two corresponding slots, and a salt-blocking sealing strip is provided between the slots and the baffle 313.

[0064] According to a second aspect of the present invention, a test method is also provided, applied to the wire isothermal heat treatment test apparatus provided in the first aspect of the present invention, the test method comprising the following steps: The wire rods 1000 to be heat-treated are placed in the first bearing area 110 according to the set distribution pattern; The internal temperature of the heating furnace 200 is controlled to rise to a first set temperature, and the molten salt in the first lower salt tank 320 is heated to a second set temperature, and the molten salt in the second lower salt tank 330 is heated to a third set temperature; The robotic arm 500 is controlled to transfer the wire rod 1000 located in the first bearing area 110 into the heating furnace 200; After the heating furnace 200 heats the wire rod 1000, the control robot 500 transfers the wire rod 1000 located in the heating furnace 200 to the bracket 400; The first conveying component is controlled to circulate molten salt at a second set temperature between the first lower salt tank 320 and the upper salt tank 310, so that the wire rod 1000 located on the bracket 400 is immersed in the molten salt at the second set temperature for the first stage of isothermal heat treatment. After the first stage of isothermal heat treatment is completed, the first conveying component is stopped and the second conveying component is controlled to circulate the molten salt at the third set temperature between the second lower salt tank 330 and the upper salt tank 310, so that the wire rod 1000 located on the bracket 400 is immersed in the molten salt at the third set temperature for the second stage of isothermal heat treatment. After the second stage of isothermal heat treatment is completed, the second conveying component is stopped, and the robot arm 500 is controlled to transfer the wire rod 1000 located on the bracket 400 to the second bearing area 120.

[0065] The control method of this embodiment involves setting independent first lower salt tanks 320 and second lower salt tanks 330 below the upper salt tank 310. The first lower salt tank 320 is circulatedly connected to the upper salt tank 310 through a first conveying component, and the second lower salt tank 330 is circulatedly connected to the upper salt tank 310 through a second conveying component. During the isothermal heat treatment test of the wire rod 1000, the robot arm 500 is first controlled to transfer the wire rod 1000 to be heat-treated into the heating furnace 200 for heating. At the same time, the first heater 321 is controlled to heat the molten salt in the first lower salt tank 320 to a second set temperature, and the second heater 331 is controlled to heat the molten salt in the second lower salt tank 330 to a third set temperature. After the heating furnace 200 has finished heating the wire rod 1000, the robot arm 500 is controlled to transfer the wire rod 1000 in the heating furnace 200 to the bracket 400. Then, the first conveying component is controlled to transfer the wire rod 1000 to the bracket 400. Molten salt at a second set temperature circulates between the first lower salt tank 320 and the upper salt tank 310. At this time, the wire rod 1000 located on the bracket 400 is immersed in the dynamic molten salt at the second set temperature for the first stage of isothermal heat treatment. After the first stage of isothermal heat treatment is completed, the first conveying component is stopped, and the second conveying component is controlled to circulate molten salt at a third set temperature between the second lower salt tank 330 and the upper salt tank 310. At this time, the wire rod 1000, which has just completed the first stage of isothermal heat treatment, is immersed in the dynamic molten salt at the third set temperature for the second stage of isothermal heat treatment. This allows for the simulation of salt bath isothermal heat treatment processes under different molten salt flow fields in the same experimental device, and also enables the conduct of graded salt bath isothermal heat treatment experiments. This helps to study the effects of graded salt bath heat treatment processes and molten salt flow fields on the properties of steel, thereby accelerating the research and development of new salt bath isothermal heat treatment processes.

[0066] Although embodiments of the present invention have been described in conjunction with the accompanying drawings, those skilled in the art can make various modifications and variations without departing from the spirit and scope of the present invention, and such modifications and variations all fall within the scope defined by the present invention.

Claims

1. A wire isothermal heat treatment test apparatus, characterized in that, include: The feeding rack (100) has a first bearing area (110) for placing the wire rod (1000) to be heat treated. A heating furnace (200) is used to heat wire rod (1000) to a first set temperature. A salt bath (300) includes an upper salt tank (310) and a first lower salt tank (320) and a second lower salt tank (330) located below the upper salt tank (310). A first heater (321) is provided in the first lower salt tank (320) to heat the molten salt in the first lower salt tank (320) to a second set temperature. A second heater (331) is provided in the second lower salt tank (330) to heat the molten salt in the second lower salt tank (330) to a third set temperature. The first set temperature is greater than the second set temperature and greater than the third set temperature. The second set temperature and the third set temperature are set to be different. The first lower salt tank (320) and the upper salt tank (310) are circulatedly connected through a first conveying component. The second lower salt tank (330) and the upper salt tank (310) are circulatedly connected through a second conveying component. A bracket (400) is disposed within the upper salt tank (310); A robotic arm (500) is used to transfer the wire rod (1000) located in the first bearing area (110) to the interior of the heating furnace (200) and to transfer the wire rod (1000) located inside the heating furnace (200) to the bracket (400).

2. The wire isothermal heat treatment test apparatus according to claim 1, characterized in that, The upper salt tank (310) has a salt inlet pipe (311) connected to one side in the horizontal direction. An overflow trough (312) is provided on the outside of the first side wall of the upper salt tank (310). The top height of the first side wall is lower than the top height of the other side walls of the upper salt tank (310). A first inlet (322) is provided through the first lower salt tank (320). The first inlet (322) is connected to the overflow trough (312). The first inlet (322) is controlled to open or close by a first control component. The first conveying component includes: The first salt inlet pipe (610) has one end connected to the interior of the first lower salt tank (320) and the other end connected to the salt inlet pipe (311); The first molten salt pump (620) is mounted on the first salt inlet pipe (610).

3. The wire isothermal heat treatment test apparatus according to claim 2, characterized in that, The second lower salt tank (330) is provided with a second inlet (332), which is connected to the overflow tank (312). The second inlet (332) is controlled to open or close by a second control component. The second conveying component includes: The second salt inlet pipe (710) has one end connected to the interior of the second lower salt tank (330) and the other end connected to the salt inlet pipe (311); The second molten salt pump (720) is installed on the second salt inlet pipe (710).

4. The wire isothermal heat treatment test apparatus according to claim 3, characterized in that, The first molten salt pump (620) drives molten salt to flow in the first salt inlet pipe (610) at a first flow rate, and the second molten salt pump (720) drives molten salt to flow in the second salt inlet pipe (710) at a second flow rate, wherein the first flow rate and the second flow rate are set to be different.

5. The wire isothermal heat treatment test apparatus according to claim 3, characterized in that, The second control component includes a second plug (810) and a second drive (820). The second plug (810) has a first state in which it is driven by the second drive (820) to move closer to the second inlet (332) and block the second inlet (332), and a second state in which it is driven by the second drive (820) to move away from the second inlet (332) and open the second inlet (332).

6. The wire isothermal heat treatment test apparatus according to claim 3, characterized in that, The second conveying assembly also includes a second three-way valve (730), the first port of which is connected to the second salt inlet pipe (710), the second port of which is connected to the salt inlet pipe (311), and the third port of which is connected to a second return pipe, which communicates with the interior of the second lower salt tank (330).

7. The wire isothermal heat treatment test apparatus according to any one of claims 2 to 6, characterized in that, The first control component includes a first plug (910) and a first drive (920). The first plug (910) has a third state in which it is driven by the first drive (920) to move closer to the first inlet (322) and block the first inlet (322), and a fourth state in which it is driven by the first drive (920) to move away from the first inlet (322) and open the first inlet (322). And / or, the first conveying assembly further includes a first three-way valve (630), the first port of the first three-way valve (630) being connected to the first salt inlet pipe (610), the second port of the first three-way valve (630) being connected to the salt inlet pipe (311), and the third port of the first three-way valve (630) being connected to a first return pipe, the first return pipe being in communication with the interior of the first lower salt tank (320).

8. The wire isothermal heat treatment test apparatus according to claim 2 or 3, characterized in that, One of the baffles (313) of different heights and sizes is detachably installed in the upper salt tank (310) and serves as the first side wall. The projection of the bracket (400) and the wire rod (1000) located on the bracket (400) in the horizontal direction falls within the range of the baffle (313).

9. The wire isothermal heat treatment test apparatus according to claim 1, characterized in that, The top of the feeding rack (100) also has a second bearing area (120) for placing heat-treated wire rod (1000), and the robot (500) is also used to transfer the wire rod (1000) located on the bracket (400) to the second bearing area (120). And / or, the wire rod (1000) is in a straightened state, and the top of the bracket (400) has a groove for positioning and supporting the wire rod (1000).

10. A test method, characterized in that, The wire isothermal heat treatment test apparatus used in any one of claims 1 to 9, the test method comprising the following steps: The wire rod (1000) to be heat-treated is placed in the first bearing area (110) according to the set distribution pattern. The internal temperature of the heating furnace (200) is controlled to rise to a first set temperature, and the molten salt in the first lower salt tank (320) is heated to a second set temperature, and the molten salt in the second lower salt tank (330) is heated to a third set temperature; The control robot (500) transfers the wire rod (1000) located in the first bearing area (110) into the heating furnace (200); After the heating furnace (200) heats the wire rod (1000), the robot (500) is controlled to transfer the wire rod (1000) located in the heating furnace (200) to the bracket (400). The first conveying assembly is controlled to circulate molten salt at a second set temperature between the first lower salt tank (320) and the upper salt tank (310), so that the wire rod (1000) located on the bracket (400) is immersed in the molten salt at the second set temperature for the first stage of isothermal heat treatment. After the first stage of isothermal heat treatment is completed, the first conveying component is stopped and the second conveying component is controlled to circulate the molten salt at the third set temperature between the second lower salt tank (330) and the upper salt tank (310), so that the wire rod (1000) located on the bracket (400) is immersed in the molten salt at the third set temperature for the second stage of isothermal heat treatment. After the second stage of isothermal heat treatment is completed, the second conveying component is stopped and the robotic arm (500) is removed from the wire rod (1000) located on the bracket (400).

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