Flame cutting process for manufacturing large frame casting based on wide and thick continuous casting billet

Abstract

The invention belongs to the technical field of metal casting machining, and particularly provides a flame cutting process for manufacturing a large frame casting based on wide and thick continuous casting billets. S2, cutting gas is selected, and the selected gas is adjusted to form stable cutting flames; s3, determining an optimal cutting path and cutting speed; s4, the pretreated wide and thick continuous casting blank is cut, and a casting blank is obtained; s5, cooling treatment is conducted on the casting blank; s6, deburring and surface treatment are conducted on the cooled casting blank; and S7, the casting blank is detected. The problems that in the existing wide and thick continuous casting billet cutting process, due to the fact that the billet thickness is large, cutting is unstable, a heat affected zone is too large, and the cutting face quality is poor in a conventional gas flame cutting method are solved, the phenomena of excessive oxidation and overheating in the cutting process are reduced, the cutting precision and the cutting face quality are improved, and the cutting efficiency is improved. And the requirements of large frame structure castings on precision, strength and surface quality are met.

Description

Technical Field

[0001] The invention belongs to the technical field of metal casting processing, and in particular relates to a flame cutting process for manufacturing a large frame casting based on a wide and thick continuous casting billet. Background Art

[0002] With the development of modern industry, especially the increasing demand in heavy machinery, transportation, energy, aerospace and other industries, large frame structure castings have occupied an important position in equipment manufacturing. Wide and thick continuous casting billets have gradually become the raw materials for large castings due to their large cross-section and good consistency. However, during the processing of wide and thick continuous casting billets, due to their large material size, heavy weight, high surface quality requirements, and difficulty in controlling the heat affected zone, they are prone to low cutting efficiency, severe tool wear, rough cutting surface, cracks and other defects on the billet surface, affecting the subsequent processing and performance of the casting blank. Gas flame cutting technology has been widely used in the steel industry due to its simple operation, low cost and good cutting effect. However, in the cutting process of wide and thick continuous casting billets, due to the large thickness of the billet, conventional gas flame cutting methods often have problems such as unstable cutting, excessive heat affected zone, and poor cutting surface quality. Therefore, how to improve cutting accuracy and efficiency and reduce the heat affected zone has become a technical problem that needs to be solved in this field.

[0003] The Chinese patent with the publication number CN117773053A discloses a method for manufacturing defect-free continuous casting billets of high Ni steel, the following steps: select a slab continuous casting machine → casting tundish → water-cooled crystallizer → billet drawing → strong cooling by mist cooling → weak cooling by mist cooling in the bending section → weak cooling by mist cooling in the arc section → weak cooling in the straightening section → the continuous casting billet after flame cutting enters the cooling bed. Beneficial effect: solves the surface cracks and internal quality problems that are easy to occur in high Ni steel billets. The basic feature of the patent of the present invention is that the plastic temperature zone of Ni-containing steel and the phase transition temperature characteristics during the cooling process are analyzed, and the cooling water volume of the crystallizer and the second cooling section is controlled to further reduce the crystallizer outlet and the surface temperature of the curved billet during the continuous casting process, control the arc section temperature recovery rate, reduce stress, and improve the surface and internal quality of the billet. The document also does not solve the problems that the conventional gas flame cutting method often has unstable cutting, excessive heat-affected zone, and poor cutting surface quality due to the large billet thickness in the wide and thick continuous casting billet cutting process. Summary of the invention

[0004] The present invention provides a flame cutting process for producing large frame castings based on wide and thick continuously cast billets, with the aim of overcoming the problems in the prior art of cutting wide and thick continuously cast billets, in which the conventional gas flame cutting method often has unstable cutting, excessively large heat affected zone and poor cutting surface quality due to the large billet thickness.

[0005] To this end, the present invention provides a flame cutting process for manufacturing large frame castings based on wide and thick continuous casting billets, comprising the following steps: S1. Pre-treat the surface of the wide and thick continuous casting billet to make the surface of the wide and thick continuous casting billet reach the required standard; S2. Select cutting gas and adjust the selected gas to form a stable cutting flame; S3, determine the best cutting path and cutting speed; S4. Use a stable cutting flame to cut the pre-treated wide and thick continuous casting billet according to the optimal cutting path and cutting speed; S5, cooling the cut wide and thick continuous casting billet; S6, deburring and surface treating the wide and thick continuous casting billet after cooling treatment; S7. Inspect the wide and thick continuous casting billets after deburring and surface treatment, and those that pass the inspection are qualified castings.

[0006] Preferably, the selected gas is a mixture of oxygen and combustible gas, and the combustible gas is acetylene or propane.

[0007] Preferably, the volume ratio of acetylene to oxygen is 1:1.1-1.3, and the volume ratio of propyne to oxygen is 1:1.2-1.4.

[0008] Preferably, step S3 uses an intelligent algorithm to determine the optimal cutting path and cutting speed.

[0009] Preferably, the intelligent algorithm includes ant colony algorithm, genetic algorithm and particle swarm optimization algorithm.

[0010] Preferably, the cutting speed is 0.5-2 mm / s.

[0011] Preferably, the cutting of the pretreated wide and thick continuous casting billet includes a preheating stage and a cutting stage; the preheating stage is to heat the pretreated wide and thick continuous casting billet to a target temperature; the cutting stage is to cut the heated wide and thick continuous casting billet until the cutting is completed.

[0012] Preferably, the target temperature ranges from 500-800°C.

[0013] Preferably, during cutting in step S4, a real-time feedback flame focus adjustment device is used to monitor and adjust the flame focus.

[0014] Preferably, the cooling treatment adopts spray cooling.

[0015] Beneficial effects of the present invention: 1. The flame cutting process for making large frame castings based on wide and thick continuous casting billets provided by the present invention comprises the following steps: S1, pre-treating the surface of the wide and thick continuous casting billets to make the surface of the wide and thick continuous casting billets reach the required standard; S2, selecting a cutting gas, and adjusting the selected gas to form a stable cutting flame; S3, determining the best cutting path and cutting speed; S4, using a stable cutting flame, and cutting the pre-treated wide and thick continuous casting billets according to the best cutting path and cutting speed; S5, cooling the cut wide and thick continuous casting billets; S6, deburring and surface treating the cooled wide and thick continuous casting billets; S7, inspecting the deburred and surface treated wide and thick continuous casting billets, and the wide and thick continuous casting billets that pass the inspection are the finished castings. The present invention solves the problems encountered by traditional cutting methods in processing thick billets by selecting cutting gas, adjusting the selected gas to form a stable cutting flame, determining the best cutting path and cutting speed, and cooling, deburring and surface treating the casting billet, thereby reducing excessive oxidation and overheating during the cutting process, significantly improving cutting accuracy and the quality of the cutting surface, reducing the number of rework times due to uneven cutting, improving production efficiency, and reducing production costs, and can meet the requirements of large-scale frame structure castings in terms of accuracy, strength and surface quality.

[0016] 2. In the flame cutting process for producing large frame castings based on wide and thick continuous casting billets provided by the present invention, the selected gas is a mixture of oxygen and combustible gas, and the combustible gas is acetylene or propane. Oxygen provides high temperature, and acetylene or propane provides combustion energy, so that the flame can reach a sufficient temperature and can quickly melt and blow away the metal in the cutting area.

[0017] 3. The flame cutting process for producing large frame castings based on wide and thick continuous casting billets provided by the present invention uses an intelligent algorithm to determine the optimal cutting path and cutting speed. It can plan the shortest path in complex workpiece shapes and irregular contours and avoid irregular cutting, thereby improving the overall cutting efficiency.

[0018] 4. The flame cutting process for producing large frame castings based on wide and thick continuous casting blanks provided by the present invention can quickly reduce the temperature by using spray cooling to ensure the quality of the casting blanks. BRIEF DESCRIPTION OF THE DRAWINGS

[0019] The present invention will be further described in detail below with reference to the accompanying drawings.

[0020] Figure 1 This is a schematic diagram of the flame cutting process for making large frame castings based on wide and thick continuous casting billets. DETAILED DESCRIPTION

[0021] The principles and features of the present invention are described below in conjunction with the accompanying drawings. The examples are only used to explain the present invention and are not used to limit the scope of the present invention. If specific conditions are not specified in the embodiments, they are carried out according to normal conditions or conditions recommended by the manufacturer. If the manufacturer is not specified for the reagents or instruments used, they are all conventional products that can be purchased commercially.

[0022] Embodiment 1: A flame cutting process for manufacturing large frame castings based on wide and thick continuous casting billets comprises the following steps: S1. Pre-treat the surface of the wide and thick continuous casting billet to make the surface of the wide and thick continuous casting billet reach the required standard; Specifically, before gas flame cutting, the surface of the wide and thick continuous casting billet must first be pretreated to ensure that there are no serious surface defects such as oxides, impurities, cracks, etc. The pretreated wide and thick continuous casting billet can improve the cutting quality.

[0023] S2. Select cutting gas and adjust the selected gas to form a stable cutting flame; S3, determine the best cutting path and cutting speed; S4. Use a stable cutting flame to cut the pre-treated wide and thick continuous casting billet according to the optimal cutting path and cutting speed; S5, cooling the cut wide and thick continuous casting billet; S6, deburring and surface treating the wide and thick continuous casting billet after cooling treatment; S7. Inspect the wide and thick continuous casting billets after deburring and surface treatment, and those that pass the inspection are qualified castings.

[0024] The present invention solves the problems encountered by traditional cutting methods in processing thick billets by selecting cutting gas, adjusting the selected gas to form a stable cutting flame, determining the best cutting path and cutting speed, and cooling, deburring and surface treating the wide and thick continuous casting billets after cutting, thereby reducing excessive oxidation and overheating during the cutting process, significantly improving cutting accuracy and the quality of the cutting surface, reducing the number of rework times due to uneven cutting, improving production efficiency, reducing production costs, and being able to meet the requirements of large-scale frame structure castings in terms of accuracy, strength and surface quality.

[0025] Embodiment 2: Based on Example 1, the selected gas is a mixture of oxygen and combustible gas, and the combustible gas is acetylene or propane.

[0026] Specifically, oxygen provides high temperature, acetylene or propane provides combustion energy, and by adjusting the gas flow and pressure, a stable and high-temperature flame is formed to ensure the efficiency of the cutting process and the quality of the cutting surface.

[0027] Preferably, the volume ratio of acetylene to oxygen is 1:1.1-1.3, and the volume ratio of propyne to oxygen is 1:1.2-1.4.

[0028] Specifically, the mixed gas composed of this ratio can easily form a stable cutting flame, the cutting temperature reaches above 3000°C, and the metal in the cutting area can be quickly melted and blown away.

[0029] Preferably, the selected gas is adjusted through a gas flow control valve to adjust the flow of oxygen and combustible gas, so that the desired cutting flame can be easily formed.

[0030] Embodiment 3: Based on Example 2, step S3 uses an intelligent algorithm to determine the optimal cutting path and cutting speed.

[0031] Specifically, by using intelligent algorithms to determine the best cutting path and cutting speed, it is possible to plan the shortest path in complex workpiece shapes and irregular contours and avoid irregular cutting, and avoid deformation caused by continuous large-area cutting. According to the thickness and shape of the casting billet, the cutting feed angle is adjusted, the cutting trajectory is optimized, the flatness and accuracy of the cutting surface are ensured, and the overall cutting efficiency is improved.

[0032] Preferably, the intelligent algorithm includes ant colony algorithm, genetic algorithm and particle swarm optimization algorithm.

[0033] Specifically, the ant colony algorithm, genetic algorithm and particle swarm optimization algorithm can quickly and accurately calculate the best cutting path. Ant colony algorithm, genetic algorithm and particle swarm optimization algorithm are all existing algorithms. Based on the actual shape and size of the wide and thick continuous casting billet, the cutting feed angle and path are optimized to make the cutting process smoother and more accurate, avoiding irregular cutting and multiple adjustments in traditional methods, and improving the overall cutting efficiency.

[0034] Preferably, the cutting speed is 0.5-2 mm / s.

[0035] Specifically, the cutting speed is 0.5-2 mm / s, the cutting is stable and the cutting quality is good.

[0036] Embodiment 4: Based on Example 3, the cutting of the pretreated wide and thick continuous casting billet includes a preheating stage and a cutting stage; the preheating stage is to heat the pretreated wide and thick continuous casting billet to the target temperature; the cutting stage is to cut the heated wide and thick continuous casting billet until the cutting is completed.

[0037] Specifically, the pre-treated wide and thick continuous casting billet is heated to the target temperature to reduce the thermal stress and cracks that may be generated during the cutting process. When the surface of the wide and thick continuous casting billet reaches the target temperature, oxygen is introduced into the selected gas flame to react with the metal to generate iron oxide and take away the metal, completing the cutting.

[0038] Preferably, the preheating stage is to uniformly heat the pretreated wide and thick continuous casting billet to a target temperature.

[0039] Specifically, the surface of the wide and thick continuous casting billet is evenly heated during the preheating process to prevent excessive temperature differences. By evenly heating the billet surface, the cutting instability caused by the temperature difference is reduced, and the risk of cracks caused by the temperature difference is reduced.

[0040] Preferably, the target temperature ranges from 500-800°C.

[0041] Specifically, before cutting, the surface of the wide and thick continuous casting billet is preheated and the temperature is controlled between 500-800°C. By uniformly heating the billet surface, the cutting instability caused by the temperature difference is reduced, and the risk of cracks caused by the temperature difference is reduced.

[0042] Preferably, the heating is performed by a gas combustion heater or a resistance heating furnace, which is easy to operate and low in cost.

[0043] Embodiment 5: On the basis of Example 4, during cutting in step S4, a real-time feedback flame focus adjustment device is used to monitor and adjust the flame focus.

[0044] Specifically, during the cutting process, the existing real-time feedback flame focus adjustment device is used. The temperature distribution and material state of the cutting area are monitored in real time through high-precision sensors, and the position of the flame focus and the gas flow rate are automatically adjusted to keep the flame in the best cutting state at all times, greatly improving the stability and accuracy of the cutting process. At the same time, by accurately adjusting the gas flow rate and cutting speed, the uniformity and stability of the cutting are ensured to avoid overheating or material damage in the cutting area.

[0045] Preferably, during the cutting, a dynamic thermal monitoring device is also used to monitor the surface temperature and thermal gradient of the wide and thick continuous casting billet in real time, and the gas flow rate and cutting speed are intelligently adjusted in combination with an adaptive algorithm.

[0046] Specifically, the dynamic thermal monitoring device is an existing device that introduces dynamic thermal monitoring technology to monitor the surface temperature and thermal gradient of wide and thick continuous casting billets in real time, and combines adaptive algorithms to intelligently adjust the gas flow and cutting speed to ensure uniform distribution of heat input, effectively preventing local overheating and defects such as cracks and deformation caused by excessive temperature differences.

[0047] Embodiment 6: Based on Example 5, the cooling treatment adopts spray cooling.

[0048] Specifically, after cutting is completed, a high-temperature area will appear in the heat-affected zone of the casting blank, which is likely to cause stress concentration and surface hardening. The temperature can be quickly reduced by spray cooling or water cooling to ensure the quality of the casting blank.

[0049] After cutting, the surface of the casting blank may have some oxide scale and irregularities. In order to improve the surface quality and dimensional accuracy, it is further processed through subsequent mechanical processing (such as grinding, deburring, etc.) to ensure that the blank meets the requirements of subsequent processing. After cutting, necessary post-processing is carried out, including removing oxides and impurities in the cutting area to ensure that the cutting surface is smooth and flat.

[0050] Preferably, the spray cooling is performed by spraying using a water spray device.

[0051] Specifically, the cooling process is achieved through a water spray device, and the spray water flow rate and the cooling speed are controlled to reduce thermal stress.

[0052] Preferably, the deburring is performed by mechanical polishing or electrolytic polishing. The deburring effect is good, ensuring that the cut surface is smooth and burr-free, further improving the flatness and smoothness of the cut surface, and laying a foundation for subsequent processing and use.

[0053] Preferably, when the casting blank is inspected, the inspection method includes ultrasonic inspection, laser measurement and visual inspection.

[0054] Specifically, the cutting accuracy is tested through ultrasonic testing, laser measurement and visual testing to ensure that the quality of the casting blank meets the standard requirements. The surface roughness test is carried out using a surface roughness tester.

[0055] Embodiment 7: Based on Example 6, a flame cutting device for manufacturing a large-scale frame structure casting blank based on a wide and thick continuous casting blank comprises: Temperature control heating equipment, used to preheat the surface of wide and thick continuous casting billets before cutting; Flame cutting machine, used for flame cutting of wide and thick continuous casting billets; An adjustable gas supply device is used to provide the required gas to the flame cutting machine; A cooling device is used to cool the wide and thick continuous casting billet after cutting; The quality inspection device is used to inspect the wide and thick continuous casting billets after deburring and surface treatment.

[0056] Preferably, the flame cutting machine can realize automatic adjustment of the feed speed and cutting path to adapt to wide and thick continuous casting billets of different shapes and thicknesses.

[0057] Preferably, the cooling device includes a water spray device; it can automatically adjust the spray water flow rate according to the size and temperature of the cut casting blank, and the water flow rate range is 10L / min to 200L / min. When the casting temperature exceeds 500°C, the water spray flow rate automatically increases, and the adjustment response time of the water spray equipment does not exceed 3 seconds.

[0058] The present invention has the following advantages: 1. Improve cutting accuracy: By optimizing cutting parameters and controlling gas flow, excessive oxidation and overheating during the cutting process are reduced, and the cutting accuracy and the quality of the cutting surface are significantly improved.

[0059] 2. Improve production efficiency: Optimized cutting parameters and process sequence increase cutting speed and reduce the number of reworks caused by uneven cutting, thereby improving production efficiency and reducing production costs.

[0060] 3. Adapt to wide and thick continuous casting billets: This process is particularly suitable for large-size, high-thickness wide and thick continuous casting billets, and can meet the requirements of large-scale frame structure castings in terms of precision, strength and surface quality.

[0061] In the description of the present invention, it should be understood that if any term indicates an orientation or positional relationship, it is based on the orientation or positional relationship shown in the drawings, rather than indicating or implying that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation. Therefore, the terms describing the positional relationship in the drawings are only used for illustrative purposes and cannot be understood as a limitation on the present invention.

[0062] The above embodiments are merely examples of the present invention and do not limit the protection scope of the present invention. All designs that are the same or similar to the present invention fall within the protection scope of the present invention.

Claims

1. A flame cutting process for producing large frame castings based on wide and thick continuous casting billets, characterized in that: The steps include: S1. Pre-treat the surface of the wide and thick continuous casting billet to make the surface of the wide and thick continuous casting billet reach the required standard; S2. Select cutting gas and adjust the selected gas to form a stable cutting flame; S3, determine the best cutting path and cutting speed; S4. Use a stable cutting flame to cut the pre-treated wide and thick continuous casting billet according to the optimal cutting path and cutting speed; S5, cooling the cut wide and thick continuous casting billet; S6, deburring and surface treating the wide and thick continuous casting billet after cooling treatment; S7. Inspect the wide and thick continuous casting billets after deburring and surface treatment, and those that pass the inspection are qualified castings.

2. The flame cutting process for producing large frame castings based on wide and thick continuous casting billets according to claim 1, characterized in that: The selected gas is a mixed gas of oxygen and combustible gas, and the combustible gas is acetylene or propane.

3. The flame cutting process for producing large frame castings based on wide and thick continuous casting billets as claimed in claim 2, characterized in that: The volume ratio of acetylene to oxygen is 1:1.1-1.3, and the volume ratio of propyne to oxygen is 1:1.2-1.

4.

4. The flame cutting process for producing large frame castings based on wide and thick continuous casting billets according to claim 1, characterized in that: Step S3 uses an intelligent algorithm to determine the best cutting path and cutting speed.

5. The flame cutting process for producing large frame castings based on wide and thick continuous casting billets as claimed in claim 4, characterized in that: The intelligent algorithms include ant colony algorithm, genetic algorithm and particle swarm optimization algorithm.

6. The flame cutting process for producing large frame castings based on wide and thick continuous casting billets as claimed in claim 4, characterized in that: The cutting speed is 0.5-2 mm / s.

7. The flame cutting process for producing large frame castings based on wide and thick continuous casting billets as claimed in claim 1, characterized in that: The cutting of the pretreated wide and thick continuous casting billet includes a preheating stage and a cutting stage; the preheating stage is to heat the pretreated wide and thick continuous casting billet to a target temperature; the cutting stage is to cut the heated wide and thick continuous casting billet until the cutting is completed.

8. The flame cutting process for producing large frame castings based on wide and thick continuous casting billets as claimed in claim 7, characterized in that: The target temperature ranges from 500-800°C.

9. The flame cutting process for manufacturing large frame castings based on wide and thick continuous casting billets according to claim 1, characterized in that: During cutting in step S4, the flame focus is monitored and adjusted using a real-time feedback flame focus adjustment device.

10. The flame cutting process for manufacturing large frame castings based on wide and thick continuous casting billets according to claim 1, characterized in that: The cooling process adopts spray cooling.

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