Hot coil spiral spring surface full decarburization control method based on fuel gas heating mode

Abstract

The invention relates to the field of railway train bogie spring manufacturing, in particular to a hot coil spiral spring surface full decarburization control method based on a fuel gas heating mode, which comprises the following steps of: feeding a spring steel bar into a walking beam type fuel gas heating furnace for heating after the surface of the spring steel bar is polished; the heating furnace comprises a preheating chamber, a rapid heating chamber and a temperature equalizing chamber which are independently controlled in temperature and are communicated at the bottoms; when the temperature of the bar in the preheating chamber reaches 600-650 DEG C, the bar enters the rapid heating chamber in a stepping manner, and when the temperature of the bar in the rapid heating chamber reaches 950-980 DEG C, the bar enters the uniform temperature chamber in a stepping manner; after the spring steel bar is rolled, when the diameter phi of the spring steel bar is not larger than 28 mm, the spring steel bar enters a soaking pit furnace to be subjected to temperature equalization at 950 + / -20 DEG C, and after the temperature reaches 900 + / -20 DEG C, quenching and tempering are conducted; directly quenching and tempering when the diameter phi of the spring steel bar is greater than 28mm; and by adopting a gas heating mode, the energy consumption is reduced by more than 30%, and the manufacturing cost of the spring is obviously reduced.

Description

Technical Field

[0001] This invention relates to the field of railway train bogie spring manufacturing, specifically to a method for controlling the complete decarburization of the surface of hot-rolled helical springs based on gas heating. Background Technology

[0002] As the running gear of railway locomotives and rolling stock, the bogie's elastic suspension system buffers vibrations and impacts, ensuring smooth vehicle operation. To guarantee the safe operation of railway vehicles, the springs used in the bogie must possess sufficient fatigue strength. However, the presence of a fully decarburized layer on the spring surface can reduce the spring's fatigue life by more than 50%. Therefore, railway industry standards explicitly stipulate that the surface of bogie springs must not have a fully decarburized ferrite layer. To effectively control the formation of a fully decarburized ferrite layer during the spring heating and winding process, medium-frequency induction heating is mainly used. While this method can control the formation of a fully decarburized layer, it results in high manufacturing costs and uneven composition of the spring body. Gas heating has low energy consumption, reducing spring manufacturing costs, and the heating process homogenizes the composition of the spring body through insulation. However, springs manufactured using gas heating are highly susceptible to developing a fully decarburized ferrite layer, which does not meet the requirements of railway industry standards. Summary of the Invention

[0003] To address the shortcomings of existing technologies, this invention provides a method for controlling the complete decarburization of the surface of hot-rolled helical springs based on gas heating. By using gas heating, the heating process of the spring is controlled to prevent the formation of a completely decarburized ferrite layer, thus meeting the requirements of railway industry standards for a completely decarburized ferrite layer on the spring surface. At the same time, it reduces energy consumption and lowers the manufacturing cost of the spring.

[0004] To achieve the above objectives, the present invention provides a method for controlling the complete decarburization of the surface of a hot-rolled helical spring based on gas heating, characterized in that it includes:

[0005] After surface polishing, the spring steel bar material is fed into a walking beam gas-fired heating furnace for heating. The heating furnace includes a preheating chamber, a rapid heating chamber, and a uniform temperature chamber with independent temperature control and interconnected bottom.

[0006] When the bar temperature in the preheating chamber reaches 600 to 650 degrees, the process moves to the rapid heating chamber; when the bar temperature in the rapid heating chamber reaches 950 to 980 degrees, the process moves to the uniform temperature chamber.

[0007] After the spring steel bar stock is rolled, if the diameter of the spring steel bar stock is not greater than φ28mm, it is put into a soaking furnace and is heated at 950±20 degrees. When the temperature reaches 900±20 degrees, it is quenched and tempered. If the diameter of the spring steel bar stock is greater than φ28mm, it is directly quenched and tempered.

[0008] The preheating chamber temperature is 650 to 700 degrees Celsius, the rapid heating chamber temperature is 980 to 1000 degrees Celsius, the uniform temperature chamber temperature is 920 to 950 degrees Celsius, and the spring steel bar material exiting the uniform temperature chamber is synchronized with the spring winding cycle.

[0009] Preferably, the preheating chamber, rapid heating chamber, and uniform temperature chamber of the walking beam gas heater are independently temperature controlled based on PID, and the stepping cycle of each chamber is controlled separately.

[0010] Furthermore, the temperature setting of the rapid heating chamber is 30-80 degrees higher than that of the uniform temperature chamber.

[0011] Furthermore, the surface polishing process removes all visible decarburized layers from the surface;

[0012] The surface roughness after polishing is no greater than 1.6 μm.

[0013] Furthermore, the soaking furnace is a protective atmosphere furnace, and the oxygen content of the soaking furnace is no more than 0.5%.

[0014] Furthermore, it also includes:

[0015] The preheating chamber, rapid heating chamber, and uniform temperature chamber are connected in sequence, and each chamber has a bar material channel at the bottom;

[0016] Each chamber is equipped with an independently configured PID temperature control module;

[0017] Bar temperature probes are installed in the preheating chamber and the rapid heating chamber;

[0018] The cycle time of the stepper beam drive module corresponding to each chamber is independently adjusted based on the temperature measurement signal.

[0019] Furthermore, the cycle time of the uniform temperature chamber and the winding equipment is controlled by a PLC.

[0020] Furthermore, the temperature gradient between the rapid heating chamber and the uniform temperature chamber is dynamically adjusted by a gas flow proportional valve.

[0021] Compared with the closest existing technology, the present invention has the following advantages:

[0022] By using gas heating, energy consumption is reduced by more than 30% compared with electric heating or medium-frequency induction heating, and the manufacturing cost of springs is significantly reduced. Furthermore, through the design of the heating furnace cavity structure, the heating temperature of the bar stock is controlled in stages to prevent the formation of a completely decarburized layer on the surface of the hot-rolled helical spring during the heating process. Attached Figure Description

[0023] Figure 1This is a flowchart of a method for controlling the complete decarburization of the surface of a hot-rolled spiral spring based on gas heating, provided by the present invention.

[0024] Figure 2 This invention provides a flow chart of the heat treatment process for a hot-rolled spiral spring with a diameter not exceeding 28mm, based on a method for controlling the complete decarburization of the surface of the spring using gas heating.

[0025] Figure 3 This invention provides a flow chart of the heat treatment process for a hot-rolled spiral spring with a diameter greater than 28mm, based on a method for controlling the complete decarburization of the surface of the spring using a gas-fired heating system. Detailed Implementation

[0026] The specific embodiments of the present invention will be further described in detail below with reference to the accompanying drawings.

[0027] 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.

[0028] Example 1:

[0029] This invention provides a method for controlling the complete decarburization of the surface of a hot-rolled helical spring based on gas heating, such as... Figure 1 As shown, it includes:

[0030] S1. After surface polishing, the spring steel bar material is fed into a walking beam gas heating furnace for heating. The heating furnace includes a preheating chamber, a rapid heating chamber, and a uniform temperature chamber with independent temperature control and interconnected bottom.

[0031] S2. When the bar temperature in the preheating chamber reaches 600 to 650 degrees, step into the rapid heating chamber. When the bar temperature in the rapid heating chamber reaches 950 to 980 degrees, step into the uniform temperature chamber.

[0032] S3. After the spring steel bar stock is rolled, as follows: Figure 2 As shown, spring steel bars with a diameter not exceeding φ28mm are placed in a soaking furnace at 950±20 degrees Celsius for homogenization. After reaching 900±20 degrees Celsius, they are quenched and tempered. Figure 3 As shown, when the diameter of the spring steel bar is greater than φ28mm, it should be directly quenched and tempered.

[0033] The preheating chamber temperature is 650 to 700 degrees Celsius, the rapid heating chamber temperature is 980 to 1000 degrees Celsius, the uniform temperature chamber temperature is 920 to 950 degrees Celsius, and the spring steel bar material exiting the uniform temperature chamber is synchronized with the spring winding cycle.

[0034] The preheating chamber, rapid heating chamber, and homogenizing chamber of the walking beam gas heater are independently temperature-controlled based on PID, and the stepping cycle of each chamber is controlled separately; the temperature setpoint of the rapid heating chamber is 30-80 degrees higher than that of the homogenizing chamber; the surface polishing process removes all visible decarburized layers; the surface roughness of the polishing process is no greater than 1.6 μm; the homogenizing furnace is a protective atmosphere furnace, and the oxygen content of the homogenizing furnace is no greater than 0.5%.

[0035] In this embodiment, the method for controlling the complete decarburization of the surface of a hot-rolled spiral spring based on gas heating also includes:

[0036] The preheating chamber, rapid heating chamber, and uniform temperature chamber are connected in sequence, and each chamber has a bar material channel at the bottom;

[0037] Each chamber is equipped with an independently configured PID temperature control module;

[0038] Bar temperature probes are installed in the preheating chamber and the rapid heating chamber;

[0039] The cycle time of the stepping beam drive module corresponding to each chamber is independently adjusted according to the temperature measurement signal;

[0040] The cycle time of the uniform temperature chamber and the rolling equipment is controlled by a PLC;

[0041] The temperature gradient between the rapid heating chamber and the uniform temperature chamber is dynamically adjusted by a gas flow proportional valve.

[0042] Those skilled in the art will understand that embodiments of the present invention can be provided as methods, systems, or computer program products. Therefore, the present invention can take the form of a completely hardware embodiment, a completely software embodiment, or an embodiment combining software and hardware aspects. Furthermore, the present invention can take the form of a computer program product embodied on one or more computer-usable storage media (including, but not limited to, disk storage, CD-ROM, optical storage, etc.) containing computer-usable program code.

[0043] This invention is described with reference to flowchart illustrations and / or block diagrams of a method, apparatus (system), and computer program product for controlling the complete decarburization of the surface of a hot-rolled spiral spring based on a gas heating method, according to embodiments of this application. It should be understood that each block of the flowchart illustrations and / or block diagrams, and combinations of blocks in the flowchart illustrations and / or block diagrams, can be implemented by computer program instructions. These computer program instructions can be provided to a processor of a general-purpose computer, special-purpose computer, embedded processor, or other programmable data processing device to produce a machine, such that the instructions, which execute via the processor of the computer or other programmable data processing device, generate instructions for implementing the process... Figure 1 One or more processes and / or boxes Figure 1 A device that provides the functions specified in one or more boxes.

[0044] These computer program instructions may also be stored in a computer-readable storage medium that can direct a computer or other programmable data processing device to function in a particular manner, such that the instructions stored in the computer-readable storage medium produce an article of manufacture including instruction means, which are implemented in a process Figure 1 One or more processes and / or boxes Figure 1 The function specified in one or more boxes.

[0045] These computer program instructions may also be loaded onto a computer or other programmable data processing equipment to cause a series of operational steps to be performed on the computer or other programmable equipment to produce a computer-implemented process, thereby providing instructions that execute on the computer or other programmable equipment for implementing the process. Figure 1 One or more processes and / or boxes Figure 1 The steps of the function specified in one or more boxes.

[0046] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of the present invention and not to limit it. Although the present invention has been described in detail with reference to the above embodiments, those skilled in the art should understand that modifications or equivalent substitutions can still be made to the specific implementation of the present invention. Any modifications or equivalent substitutions that do not depart from the spirit and scope of the present invention should be covered within the scope of protection of the claims of the present invention.

Claims

1. A method for controlling the complete decarburization of the surface of a hot-rolled helical spring based on gas heating, characterized in that, include: After surface polishing, the spring steel bar material is fed into a walking beam gas-fired heating furnace for heating. The heating furnace includes a preheating chamber, a rapid heating chamber, and a uniform temperature chamber with independent temperature control and interconnected bottom. When the bar temperature in the preheating chamber reaches 600 to 650 degrees, the process moves to the rapid heating chamber; when the bar temperature in the rapid heating chamber reaches 950 to 980 degrees, the process moves to the uniform temperature chamber. After the spring steel bar stock is rolled, if the diameter of the spring steel bar stock is not greater than φ28mm, it is put into a soaking furnace and is heated at 950±20 degrees. When the temperature reaches 900±20 degrees, it is quenched and tempered. If the diameter of the spring steel bar stock is greater than φ28mm, it is directly quenched and tempered. The preheating chamber temperature is 650 to 700 degrees Celsius, the rapid heating chamber temperature is 980 to 1000 degrees Celsius, the uniform temperature chamber temperature is 920 to 950 degrees Celsius, and the spring steel bar material exiting the uniform temperature chamber is synchronized with the spring winding cycle.

2. The method for controlling the complete decarburization of the surface of a hot-rolled helical spring based on gas heating as described in claim 1, characterized in that: The preheating chamber, rapid heating chamber, and uniform temperature chamber of the walking beam gas heater are independently temperature controlled based on PID, and the stepping cycle of each chamber is controlled separately.

3. The method for controlling the complete decarburization of the surface of a hot-rolled helical spring based on gas heating as described in claim 2, characterized in that: The temperature setting of the rapid heating chamber is 30-80 degrees higher than that of the uniform temperature chamber.

4. The method for controlling the complete decarburization of the surface of a hot-rolled helical spring based on gas heating as described in claim 1, characterized in that: The surface polishing process removes all visible decarburized layers from the surface. The surface roughness after polishing is no greater than 1.6 μm.

5. The method for controlling the complete decarburization of the surface of a hot-rolled helical spring based on gas heating as described in claim 1, characterized in that: The soaking furnace is a protective atmosphere furnace, and the oxygen content of the soaking furnace is no more than 0.5%.

6. A method for controlling the complete decarburization of the surface of a hot-rolled spiral spring based on gas heating, characterized in that, Also includes: The preheating chamber, rapid heating chamber, and uniform temperature chamber are connected in sequence, and each chamber has a bar material channel at the bottom; Each chamber is equipped with an independently configured PID temperature control module; Bar temperature probes are installed in the preheating chamber and the rapid heating chamber; The cycle time of the stepper beam drive module corresponding to each chamber is independently adjusted based on the temperature measurement signal.

7. The method for controlling the complete decarburization of the surface of a hot-rolled helical spring based on gas heating as described in claim 6, characterized in that: The temperature equalization chamber and the rolling equipment are controlled by a PLC.

8. The method for controlling the complete decarburization of the surface of a hot-rolled helical spring based on gas heating as described in claim 7, characterized in that: The temperature gradient between the rapid heating chamber and the uniform temperature chamber is dynamically adjusted by a gas flow proportional valve.

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