CN214168053U - Controllable cooling device of nitrogen gas refrigerated response quenching - Google Patents

Abstract

The utility model provides a controllable cooling device of nitrogen gas refrigerated response quenching, include: a preheating chamber for preheating the workpiece; the induction coil spraying sleeve is composed of induction coils and spraying sleeves which are spirally arranged side by side so as to quickly perform induction heating and cooling on the preheated workpiece; a heat preservation furnace for performing heat preservation treatment on the cooled workpiece; and the nitrogen supply system is used for supplying high-pressure nitrogen or supercritical nitrogen to the injection sleeve. According to the controllable cooling device for the nitrogen-cooled induction quenching, the environment-friendly nitrogen is used as the coolant, and the cooling rate of the workpiece is accurately controlled by adjusting the preheating and heat-preserving process parameters of the workpiece, the temperature, the pressure and the flow rate of the coolant, so that the cooling rate of the workpiece is close to an ideal cooling curve as far as possible, the workpiece obtains high strength and fatigue resistance, the energy and material consumption is saved, the production efficiency is improved, and the production cost is reduced.

Description

Controllable cooling device of nitrogen gas refrigerated response quenching

Technical Field

The utility model relates to the technical field of heat treatment, in particular to a controllable cooling device for induction quenching of nitrogen cooling.

Background

The existing heat treatment process generally adopts a vacuum furnace quenching process to quench workpieces in a vacuum atmosphere or an air atmosphere; or quenching treatment is carried out by using a continuous furnace and adopting a quenching medium such as quenching liquid; or an induction hardening machine (when processing large-sized workpieces or rotary discs) is adopted to carry out hardening treatment on the surface of the product. In these techniques, the vacuum heat treatment equipment has a complex structure and low equipment reliability and stability; the vacuum furnace can only adopt a batch production mode, the production efficiency is low, and the production cost is high.

The induction quenching is a heat treatment method for obtaining a specific surface structure and hardness, which utilizes the principle of electromagnetic induction to enable a workpiece to cut magnetic lines in an alternating magnetic field, generates induction current on the surface of the workpiece, rapidly heats the surface of the workpiece in an eddy current mode according to the skin effect of alternating current, and then rapidly cools the workpiece. The induction quenching has the advantages of high heating rate, high production efficiency and energy conservation, and the method has wide application in the surface hardening of shaft parts and plays an important role in the field of heat treatment.

At present, the commonly used induction quenching coolant in China is water cooling, and has the defects of simple cooling method, uncontrollable cooling rate and incapability of realizing some special cooling process requirements, thereby greatly limiting the application range of the process.

SUMMERY OF THE UTILITY MODEL

The utility model discloses the technical problem that will solve is: aiming at the defects of the prior art, the controllable cooling device for the induction quenching by nitrogen cooling is provided.

The utility model discloses a solve above-mentioned technical problem and adopt following technical scheme:

the utility model provides a controllable cooling device of nitrogen gas refrigerated response quenching, include:

a preheating chamber for preheating the workpiece;

the induction coil spraying sleeve is composed of induction coils and spraying sleeves which are spirally arranged side by side so as to quickly perform induction heating and cooling on the preheated workpiece;

a heat preservation furnace for performing heat preservation treatment on the cooled workpiece; and

and the nitrogen supply system is used for supplying high-pressure nitrogen or supercritical nitrogen to the injection sleeve.

Further, on the controllable cooling device for induction quenching cooled by nitrogen, the induction coil injection sleeve is of an integrated structure integrating induction heating and cooling injection, which is formed by spirally bending a double-hole copper pipe, and circulating cooling water is communicated in the copper pipe forming the induction coil; the inner side wall of the copper pipe forming the injection sleeve is provided with a plurality of vent holes which are communicated with the nitrogen supply system.

Further, on the controllable cooling device of nitrogen gas refrigerated response quenching, revolving stage and infrared temperature sensor have been arranged to the response quenching station position in the induction coil injection cover, infrared temperature sensor set up in the work piece surface, the work piece place in on the revolving stage.

Furthermore, on the controllable cooling device for induction quenching cooled by nitrogen, a post-preheating station, a pre-induction quenching station and a pre-heat-preservation station are sequentially arranged among the preheating chamber, the heat preservation furnace and the induction coil injection sleeve; and an induction quenching station is arranged in the induction coil injection sleeve.

Further preferably, on the controllable cooling device for induction quenching cooled by nitrogen, the workpiece is transferred among the post-preheating station, the pre-induction quenching station, the induction quenching station and the pre-heat-preservation station through a manipulator.

Further, on the controllable cooling device for the nitrogen-cooled induction quenching, the high-pressure nitrogen or supercritical nitrogen provided by the nitrogen supply system is filled with liquid nitrogen or prepared on site by a nitrogen making unit.

Further preferably, on the controllable cooling device of nitrogen gas refrigerated induction quenching, supply nitrogen system including the nitrogen generator group, gas holder, booster pump and the middle gas holder that connect gradually through the pipeline, wherein: the middle gas storage tank is communicated with the spraying sleeve through a pipeline to provide high-pressure nitrogen or supercritical nitrogen for the spraying sleeve.

Further preferably, a first stop valve is arranged between the nitrogen generating unit and the gas storage tank on the nitrogen-cooled induction quenching controllable cooling device; a second stop valve is arranged between the gas storage tank and the booster pump; and a regulating valve is arranged on a pipeline between the middle gas storage tank and the injection sleeve.

Further comparatively, on the controllable cooling device of nitrogen gas refrigerated induction quenching, be provided with pressure sensor and temperature sensor on the middle gas holder, be provided with flow sensor in the injection cover.

Further, the controllable cooling device for the nitrogen-cooled induction quenching further comprises a PID controller, and the PID controller is electrically connected with the induction coil, the infrared temperature sensor, the pressure sensor, the temperature sensor and the flow sensor respectively.

The utility model adopts the above technical scheme, compare with prior art, have following technological effect:

(1) the heating and cooling rates are controllable: the controllable cooling device adopts high-pressure nitrogen or supercritical nitrogen for quenching, and can realize controllable cooling of the workpiece by adjusting the pressure, temperature and flow rate of the nitrogen; and the preheating before induction quenching and the heat preservation after induction quenching are assisted, so that the complex heat treatment process such as isothermal quenching can be realized;

(2) the method is environment-friendly: the controllable cooling device adopts environment-friendly nitrogen as a coolant, and the production process is pollution-free;

(3) energy conservation: the controllable cooling device quenches the surface layer of the appointed part of the workpiece, so that the integral workpiece is not required to be heated, and heat energy is greatly saved; meanwhile, because only the surface layer at the local position is quenched, the cooling workload is greatly reduced, and the consumption of high-pressure nitrogen or supercritical nitrogen can be saved;

(4) the production efficiency is high: the induction coil injection sleeve with a special structure is adopted for rapid heating and rapid cooling, the heating and cooling time is only a few seconds or dozens of seconds, and the time is greatly saved compared with the traditional heat treatment;

(5) the cost is saved: the heat treatment cost of the workpiece is greatly reduced due to the energy and material conservation;

(6) the performance is excellent: the controllable cooling device is adopted to carry out high-frequency induction controllable quenching on the workpiece, and the cooling effect which is faster and more ideal than the traditional heat treatment can be achieved, so that the performance of the workpiece is greatly improved.

Drawings

FIG. 1 is a schematic view of the overall structure of a nitrogen-cooled induction quenching controllable cooling device of the present invention;

FIG. 2 is a schematic view of a process flow of a nitrogen-cooled induction quenching controllable cooling device of the present invention;

FIG. 3 is a schematic diagram of a cross-sectional structure of an induction coil injection sleeve of the nitrogen-cooled induction quenching controllable cooling device of the present invention;

FIG. 4 is a schematic structural view of a nitrogen supply system in the nitrogen-cooled induction quenching controllable cooling device of the present invention;

FIG. 5 is a schematic diagram of a frame of a workpiece surface temperature control system in the nitrogen-cooled induction quenching controllable cooling device of the present invention;

wherein the reference symbols are:

10-a workpiece; 20-a preheating chamber; 30-induction coil spraying sleeve, 31-induction coil, 32-cooling tube, 33-rotating table, 34-infrared temperature sensor; 40-a heat preservation furnace; 50-nitrogen supply system, 51-nitrogen making unit, 52-first stop valve, 53-gas storage tank, 54-second stop valve, 55-booster pump, 56-middle gas storage tank, 57-regulating valve, 58-pressure sensor and 59-temperature sensor; a-a post-preheating station, B-an induction quenching front station, C-an induction quenching station and D-a heat preservation front station.

Detailed Description

The technical solution of the present invention will be further described in detail with reference to the accompanying drawings.

Example 1

The embodiment provides a controllable cooling device for quenching, which adopts a heating process of preheating and induction heating, selects high-pressure nitrogen or supercritical nitrogen to replace as a coolant, adopts a spray cooling mode to rapidly cool a workpiece subjected to induction heating, and rapidly transfers the workpiece to a heat preservation chamber for subsequent cooling after the workpiece is cooled to a certain temperature; the workpiece is cooled according to a set cooling curve by accurately controlling the temperature, the pressure and the flow of the cooling gas and the temperature of the holding furnace.

Referring to fig. 1, in particular, the controllable cooling device for nitrogen-cooled induction quenching includes: a preheating chamber 20 for performing a preheating process on the workpiece 10; an induction coil spray sleeve 30, which is composed of an induction coil 31 and a spray sleeve 32 arranged side by side in a spiral manner, for performing rapid induction heating and cooling on the preheated workpiece 10; a holding furnace 40 for holding the cooled workpiece 10; and a nitrogen supply system 50 for supplying high pressure nitrogen or supercritical nitrogen to the injection sleeve 32.

In the present embodiment, please refer to fig. 1, a rotary table 33 and an infrared temperature sensor 34 are disposed at the position of the induction quenching station C in the induction coil spraying sleeve 30; the infrared temperature sensor 34 is arranged on the surface of the workpiece 10 and used for monitoring the temperature of the surface of the workpiece 10 in real time; the workpiece 10 is placed on the rotating table 33, and the workpiece 10 rotates at a certain speed in the heating and cooling processes, specifically, the rotating table 33 drives the workpiece 10 thereon to rotate in the heat treatment process, so as to improve the cooling efficiency. The power supply for high frequency induction heating of the induction coil 31 has a wide adjustable frequency and power range, and the rate and depth of heating of the workpiece is varied by adjusting the frequency and power of the power supply.

In this embodiment, please refer to fig. 1, wherein a post-preheating station a, a pre-induction quenching station B and a pre-heat-preserving station D are sequentially disposed between the preheating chamber 20, the heat-preserving furnace 40 and the induction coil injection sleeve 30; and an induction quenching station C is arranged in the induction coil injection sleeve 30; the workpiece 10 is transferred among the post-preheating station A, the induction quenching station B, the induction quenching station C and the heat-preserving station D through a manipulator.

Referring to fig. 1, the operation principle of the nitrogen-cooled induction quenching controllable cooling device is as follows: the workpiece 10 enters the preheating chamber 20, and the workpiece 10 is preheated to a certain temperature through the preheating chamber 20; then, the workpiece 10 is transferred into the induction coil spraying sleeve 30 by a robot hand for high-frequency induction heating; after the workpiece 10 is heated to a set temperature, high-pressure nitrogen or supercritical nitrogen is sprayed to the surface of the workpiece 10 through the induction coil spraying sleeve 30 so as to rapidly cool the workpiece 10, an ideal cooling curve is set according to the material, shape and service requirements of the workpiece 10, and after the temperature of the workpiece 10 is reduced to the set temperature, the workpiece 10 is conveyed to the heat preservation furnace 40 by a robot hand and then cooled according to the process requirements.

Example 2

With continued reference to fig. 1 and 2, a flow chart of a process for preheating, induction heating and heat preservation of a workpiece 10 by using the nitrogen-cooled induction quenching controllable cooling device is shown, which includes the following steps:

s1, preheating the workpiece: after the workpiece 10 is preheated to a set temperature in the holding furnace 20, the workpiece is transferred from the holding furnace 20 to a post-preheating station A according to a program and then transferred to a pre-induction quenching station B;

s2, high-frequency induction heating: grabbing the workpiece 10 from the induction quenching front station B by using a manipulator, sending the workpiece to a rotary table 33 of an induction quenching station C in an induction coil 31, introducing high-frequency current, and quickly forming a 1-3mm high-temperature area on the surface of the workpiece 10, wherein the temperature of the high-temperature area is high enough to quickly form a set tissue on the surface material of the workpiece 10;

s3, high-pressure spray cooling: after the workpiece 10 is heated to reach the set temperature and the surface thickness, high-pressure nitrogen or supercritical nitrogen is sprayed to the surface of the workpiece through the spraying sleeve 32, the workpiece 10 is forcibly cooled, and the cooling rate of the workpiece 10 is realized by adjusting the temperature, the pressure and the flow rate of the high-pressure nitrogen or the supercritical nitrogen; stopping air cooling when the temperature of the workpiece 10 reaches the set isothermal quenching temperature; the workpiece 10 is transferred to a station D before heat preservation under the action of the manipulator;

and S4, grabbing the workpiece 10 through the manipulator, and conveying the workpiece 10 into the heat preservation furnace 40 from the pre-heat preservation station D for heat preservation to finish subsequent cooling and tissue transformation.

In the present embodiment, in step S3, the rotational speed and the electrical input power density of the rotating table 33 must be precisely designed and controlled to control the rate, depth and temperature uniformity of heating.

In this embodiment, in step S3, the temperature, pressure and flow rate of the high-pressure nitrogen gas or the supercritical nitrogen gas must be precisely measured and controlled to achieve the cooling of the workpiece according to the ideal cooling curve, and the temperature of the workpiece during the cooling process is measured and controlled in real time.

The process of preheating, induction heating and heat preservation of the workpiece 10 by adopting the controllable cooling device for induction quenching cooled by nitrogen can achieve quicker and more ideal cooling effect than the traditional heat treatment, thereby greatly improving the performance of the workpiece; and energy and materials are saved, and the heat treatment cost of the workpiece is reduced.

Example 3

Referring to fig. 3, in the present embodiment, an induction coil injection sleeve 30 of an induction quenching controllable cooling device for nitrogen cooling is provided, where the induction coil injection sleeve 30 is an integrated structure of induction heating and cooling injection formed by spirally bending a double-hole copper pipe, and circulating cooling water is communicated in the copper pipe forming the induction coil 31; the inner side wall of the copper tube constituting the injection sleeve 32 is provided with a plurality of vent holes which are communicated with the nitrogen supply system 50. The workpiece 10 is heated and cooled in the induction coil spraying sleeve 30, and cooling water is used for cooling the induction coil 31 when the workpiece is heated so as to prevent the temperature of the induction coil 31 from being excessively increased; high-pressure nitrogen or supercritical nitrogen is sprayed onto the surface of the workpiece 10 through the spray sleeve 32, so that the workpiece 10 is rapidly cooled.

According to the controllable cooling device for nitrogen-cooled induction quenching, the induction coil 31 is adopted to quench only the surface layer of the designated part of the workpiece, the integral workpiece is not required to be heated, and heat energy is greatly saved; meanwhile, because only the surface layer at the local position is quenched, the cooling workload is greatly reduced, the consumption of high-pressure nitrogen or supercritical nitrogen can be saved, and the energy is saved. And the induction coil injection sleeve 30 with a special structure is adopted for rapid heating and rapid cooling, the heating and cooling time is only a few seconds or dozens of seconds, and the time is greatly saved compared with the traditional heat treatment process.

Example 4

Referring to fig. 4, the present embodiment provides a nitrogen supply system 50 for an induction hardening controllable cooling apparatus for nitrogen cooling, wherein the coolant nitrogen can be purchased as a canned gas or manufactured at a production site. In this embodiment, the high pressure nitrogen or supercritical nitrogen provided by the nitrogen supply system 50 is prepared on-site by a nitrogen generator set. The nitrogen supply system 50 comprises a nitrogen making unit 51, a gas storage tank 53, a booster pump 55 and an intermediate gas storage tank 56 which are sequentially connected through pipelines, wherein: the intermediate gas tank 56 is connected to the injection sleeve 32 through a pipe to supply high-pressure nitrogen gas or supercritical nitrogen gas to the injection sleeve 32.

In this embodiment, please refer to fig. 4, a first stop valve 52 is disposed between the nitrogen generating unit 51 and the air storage tank 53; a second stop valve 54 is arranged between the air storage tank 53 and the booster pump 55; and a regulating valve 57 is arranged on a pipeline between the intermediate air storage tank 56 and the injection sleeve 32. The intermediate gas storage tank 56 is provided with a pressure sensor 58 and a temperature sensor 59, the injection sleeve 32 is internally provided with a flow sensor, and the pressure and the temperature of the nitrogen in the intermediate gas storage tank 56 can be monitored in real time through the pressure sensor 58 and the temperature sensor 59; and the flow rate of the nitrogen sprayed by the spraying sleeve 32 can be monitored in real time through a flow sensor.

In the present embodiment, the nitrogen supply system 50 operates according to the following principle: the nitrogen making unit 51 makes nitrogen from air, enters the air storage tank 53 through the first stop valve 52, then enters the intermediate air storage tank 56 through the second stop valve 54 and the booster pump 55, the intermediate air storage tank 56 is provided with a pressure sensor 58 and a temperature sensor 59, high-pressure nitrogen or supercritical nitrogen in the intermediate air storage tank 56 for detecting the temperature and the pressure in the tank in a set working range enters the injection sleeve 32 through the regulating valve 57, and the injection sleeve 32 injects the high-pressure nitrogen or the supercritical nitrogen to the surface of the workpiece 10 to cool the workpiece 10. The temperature, pressure and flow rate of the high pressure or supercritical nitrogen gas ejected from the illustrated ejection sleeve 32 can be adjusted to achieve controlled cooling of the workpiece 10.

Example 5

Referring to fig. 5, the present embodiment further provides a workpiece cooling speed (temperature-time) control system of the induction quenching controllable cooling apparatus for nitrogen cooling, which includes two parts, i.e., a PID controller and a controlled object (functional units such as sensors). The PID controller is respectively connected with functional units such as various sensors, for example, the induction coil 31, the infrared temperature sensor 34, the pressure sensor 58, the temperature sensor 59 and the flow sensor. When the workpiece 10 is quenched by high-pressure nitrogen or supercritical nitrogen, the PID controller can adjust the pressure, temperature and flow rate of the nitrogen according to the data monitored by the infrared temperature sensor 34, the pressure sensor 58, the temperature sensor 59 and the flow sensor in real time to realize the controllable cooling of the workpiece 10; and the preheating before induction quenching and the heat preservation after induction quenching are assisted, so that the complex heat treatment process such as isothermal quenching can be realized.

The PID controller is a linear controller that performs process control based on an error e (t) between a set value r (t) and an actual output value c (t), r (t) -c (t). In the embodiment, the surface temperature y (t) of the workpiece is taken as a control object, the surface temperature of the workpiece is measured in real time by an infrared temperature sensor (34), a measured value c (t) is fed back to a PID controller, the controller outputs an analog quantity signal u (t) to the PID controller through PID regulation operation according to an error value e (t), and the PID controller regulates parameters such as the speed of a fluid influencing a heat transfer coefficient according to the output analog quantity signal u (t).

In summary, the controllable cooling device for nitrogen-cooled induction quenching provided by the utility model realizes a complex quenching process by controlling the main performance and technological parameters of coolant high-pressure nitrogen or supercritical nitrogen; the environment-friendly nitrogen is used as a coolant, and the cooling rate of the workpiece is accurately controlled by adjusting the preheating and heat-preserving process parameters of the workpiece, the temperature, the pressure and the flow rate of the coolant, so that the cooling rate of the workpiece is close to an ideal cooling curve as far as possible.

The controllable cooling device of induction quenching of nitrogen cooling provided by the utility model can be used for quenching and bainite quenching of steel, QT500 and other alloys, thereby obtaining high hardness and fatigue resistance, and solving the link problem caused by using water, oil and nitrate in the prior heat treatment device; meanwhile, the energy and material consumption is saved, the production efficiency is improved, and the production cost is reduced.

The present invention has been described in detail with reference to the specific embodiments, but the present invention is only by way of example and is not limited to the specific embodiments described above. Any equivalent modifications and substitutions to those skilled in the art are intended to be within the scope of the present invention. Accordingly, variations and modifications in equivalents may be made without departing from the spirit and scope of the invention, which is intended to be covered by the following claims.

Claims (10)

1. The controllable cooling device of nitrogen gas refrigerated induction quenching, characterized by comprising:

a preheating chamber (20) for preheating the workpiece (10);

the induction coil spraying sleeve (30) is composed of an induction coil (31) and a spraying sleeve (32) which are spirally arranged side by side so as to quickly perform induction heating and cooling on the preheated workpiece (10);

a heat preservation furnace (40) for performing heat preservation treatment on the cooled workpiece (10); and

a nitrogen supply system (50) for supplying high pressure nitrogen or supercritical nitrogen to the injection sleeve (32).

2. The controllable cooling device for induction quenching cooled by nitrogen according to claim 1, characterized in that the induction coil injection sleeve (30) is an integrated structure integrating induction heating and cooling injection, which is formed by spirally bending a double-hole copper pipe, and circulating cooling water is communicated in the copper pipe forming the induction coil (31); the inner side wall of the copper pipe forming the injection sleeve (32) is provided with a plurality of vent holes which are communicated with the nitrogen supply system (50).

3. The controllable cooling device for nitrogen-cooled induction quenching according to claim 1, characterized in that a rotary table (33) and an infrared temperature sensor (34) are arranged at the position of the induction quenching station (C) in the induction coil injection sleeve (30), the infrared temperature sensor (34) is arranged on the surface of the workpiece (10), and the workpiece (10) is placed on the rotary table (33).

4. The nitrogen-cooled induction quenching controllable cooling device according to claim 1, characterized in that a post-preheating station (a), a pre-induction quenching station (B) and a pre-heat-preservation station (D) are sequentially arranged among the preheating chamber (20), the holding furnace (40) and the induction coil injection sleeve (30); and an induction quenching station (C) is arranged in the induction coil injection sleeve (30).

5. The nitrogen-cooled induction hardening controllable cooling device according to claim 4, characterized in that the workpiece (10) is transferred by a robot between the post-preheating station (A), the pre-induction hardening station (B), the induction hardening station (C) and the pre-holding station (D).

6. The nitrogen-cooled induction quenching controllable cooling device according to claim 1, wherein the high-pressure nitrogen gas or supercritical nitrogen gas provided by the nitrogen supply system (50) is liquid nitrogen filling or is prepared on site by a nitrogen making unit.

7. The nitrogen-cooled induction quenching controllable cooling device according to claim 6, wherein the nitrogen supply system (50) comprises a nitrogen making unit (51), an air storage tank (53), a booster pump (55) and an intermediate air storage tank (56) which are connected in sequence through a pipeline, wherein: the intermediate gas storage tank (56) is communicated with the injection sleeve (32) through a pipeline to provide high-pressure nitrogen or supercritical nitrogen for the injection sleeve (32).

8. The controllable cooling device for the nitrogen-cooled induction quenching as claimed in claim 7, wherein a first stop valve (52) is arranged between the nitrogen generating unit (51) and the gas storage tank (53); a second stop valve (54) is arranged between the air storage tank (53) and the booster pump (55); and a regulating valve (57) is arranged on a pipeline between the intermediate air storage tank (56) and the injection sleeve (32).

9. The controllable cooling device for nitrogen-cooled induction quenching according to claim 7, characterized in that the intermediate air storage tank (56) is provided with a pressure sensor (58) and a temperature sensor (59), and the injection sleeve (32) is provided with a flow sensor.

10. The nitrogen-cooled induction quenching controllable cooling device according to claim 1, further comprising a PID controller electrically connected with the induction coil (31), the infrared temperature sensor (34), the pressure sensor (58), the temperature sensor (59) and the flow sensor, respectively.

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