Sand casting method and system for gear seat

Abstract

The invention relates to the technical field of sand casting, in particular to a sand casting method and system for a gear seat, and the method comprises the following steps: putting a sand core with the same shape as the gear seat into a core box, filling and surrounding the sand core by using wet sand, melting ferrous metal to output molten metal, pouring molten metal into the core box by using a pouring machine; cooling the core box through circulating cooling water, demolding the core box by using a drawing machine so as to output an initial sand mold, and sequentially carrying out residue removal and surface finishing operation on the initial sand mold so as to output a finished sand mold; determining the casting stability of the sand mold based on the variance of the pouring speed of the molten metal; if the casting stability does not meet the requirement, the output torque of a motor in the casting machine is adjusted; and if the casting reliability does not meet the requirement, the tensioning degree of the chain in the drawing machine is adjusted. The casting stability of the sand mold is improved.

Description

Technical Field

[0001] The invention relates to the technical field of sand casting, and in particular to a sand casting method and system for a gear seat. Background Art

[0002] In the existing technology, gear seats are a key component widely used in various transmission equipment, and their quality directly affects the performance and reliability of the entire mechanical system. Sand casting has become one of the common methods for manufacturing gear seats due to its mature technology, low cost, and strong adaptability.

[0003] The traditional sand casting process faces many challenges in the production of gear seats. From the perspective of the casting process, the production of sand molds is crucial. The early sand mold production process was difficult to accurately guarantee the quality of the sand mold. For example, in the process of placing sand cores and filling wet sand, improper operation could easily lead to uneven internal structure of the sand mold, thus affecting the quality of subsequent castings. Moreover, in the process of melting and pouring ferrous metals, the control of the pouring speed lacks precision, which can cause the flow state of the molten metal in the sand mold to be unstable, which may cause defects such as cold shut and insufficient pouring in the casting.

[0004] Chinese Patent Publication No.: CN117282917A discloses an integrated sand casting method and equipment, the method includes the following steps: S1, inject liquid metal into the casting cavity, and then observe whether there are pores in the liquid metal. If there are pores, the electromagnet is energized to attract the sliding seat and slide it along the slide groove to the position where the pores are generated; S2, start the motor to drive the gear to rotate, so that the outer tooth surface meshes and rotates, driving the rotating shaft to rotate. Due to the thread meshing effect, the stirring blade rotates while feeding into the liquid metal to eliminate the pores; S3, at the same time, the external pipeline is passed with coolant, and the coolant enters the interior of the rotating shaft through the annular shell and the cylindrical shell, and enters the extension channel to cool the stirring blade. It can be seen that the integrated sand casting method and equipment have the problem that the tilting mechanism of the ladle in the pouring equipment wears the bearing after long-term use, resulting in the transmission shaft rotating unsmoothly, the tilting speed is out of control, and the pouring speed is too fast, thereby causing the casting stability of the sand mold to decrease. Summary of the invention

[0005] To this end, the present invention provides a sand casting method and system for a gear seat, which is used to overcome the problem in the prior art that the tilting mechanism of the ladle in the casting equipment wears out the bearings after long-term use, resulting in uneven rotation of the transmission shaft, uncontrolled tilting speed, and excessively fast casting speed, thereby reducing the casting stability of the sand mold.

[0006] To achieve the above-mentioned purpose, the present invention provides a sand casting method for a gear seat, comprising: placing a sand core of the same shape as the gear seat into a core box, filling and surrounding the sand core with wet sand, melting ferrous metal to output molten metal, and pouring the molten metal into the core box using a pouring machine; cooling the core box by circulating cooling water, demolding the core box using a demolding machine to output an initial sand mold, and successively performing residue removal and surface finishing operations on the initial sand mold to output a finished sand mold; obtaining the pouring speed of the molten metal in several pouring cycles; determining the casting stability of the sand mold based on the variance of the pouring speed of the molten metal; if the casting stability does not meet the requirements, adjusting the output torque of the motor in the pouring machine, or determining the casting reliability of the finished sand mold based on the average demolding time of the initial sand mold; if the casting reliability does not meet the requirements, adjusting the tension of the chain in the demolding machine, or adjusting the circulation rate of the cooling water based on the number of pores on the surface of the finished sand mold.

[0007] Further, determining the casting stability of the sand mold includes:

[0008] comparing the variance of the pouring speed of the molten metal with a preset first variance;

[0009] If the variance of the pouring speed of the molten metal is greater than the preset first variance, it is determined that the casting stability of the sand mold does not meet the requirements.

[0010] Further, determining the casting reliability of the finished sand mold includes:

[0011] Comparing the variance of the pouring speed of the molten metal with the preset first variance and the preset second variance respectively;

[0012] If the variance of the pouring speed of the molten metal is greater than the preset first variance and less than or equal to the preset second variance, it is preliminarily determined that the casting reliability of the finished sand mold does not meet the requirements, and whether the casting reliability of the finished sand mold meets the requirements is evaluated based on the average demolding time of the initial sand mold.

[0013] Furthermore, the output torque of the motor in the casting machine is adjusted, including:

[0014] Comparing the variance of the pouring speed of the molten metal with the preset second variance;

[0015] If the variance of the pouring speed of the molten metal is greater than a preset second variance, the output torque of the motor in the pouring machine is increased.

[0016] Furthermore, the increase range of the output torque of the motor in the casting machine is determined by the difference between the variance of the casting speed of the molten metal and a preset second variance.

[0017] Further, the tension of the chain in the die-pulling machine is adjusted, including:

[0018] The average demolding time of the initial sand mold is compared with the preset first demolding time and the preset second demolding time respectively;

[0019] If the average demolding time of the initial sand mold is longer than the preset first demolding time, it is determined that the casting reliability of the finished sand mold does not meet the requirements;

[0020] If the average demolding time of the initial sand mold is greater than the preset first demolding time and less than or equal to the preset second demolding time, increasing the tension of the chain in the demolding machine;

[0021] If the average demolding time of the initial sand mold is greater than the preset second demolding time, it is preliminarily determined that the environmental stability of the sand casting does not meet the requirements, and whether the environmental stability of the sand casting meets the requirements is determined based on the number of pores on the surface of the finished sand mold.

[0022] Furthermore, the increase in tension of the chain in the demolding machine is determined by the difference between the average demolding time of the initial sand mold and the preset first demolding time.

[0023] Further, the circulation rate of the cooling water is adjusted, including:

[0024] Compare the number of pores on the surface of the finished sand mold with the preset number;

[0025] If the number of pores on the surface of the finished sand mold is greater than the preset number, it is determined that the environmental stability of the sand casting does not meet the requirements, and the circulation rate of the cooling water is reduced.

[0026] Furthermore, the reduction range of the circulation rate of the cooling water is determined by the difference between the number of pores on the surface of the finished sand mold and a preset number.

[0027] The present invention also provides a sand casting system for a gear seat, comprising:

[0028] A casting module, used for casting a sand core using a core box to output a finished sand mold, comprising a pouring unit for pouring the sand core to output a casting, a cooling unit connected to the pouring unit for cooling the casting, a demolding unit connected to the cooling unit for demolding the cooled casting to output an initial sand mold, and a trimming unit connected to the demolding unit for trimming the initial sand mold to output the finished sand mold;

[0029] Wherein, the pouring unit comprises a pouring machine for pouring the sand core, and the demoulding unit is a demoulding machine;

[0030] A detection module connected to the casting module, comprising a flow sensor connected to the pouring machine for detecting a pouring speed and a visual sensor for detecting the number of pores on the surface of the finished sand mold;

[0031] A control module is connected to the casting module and the detection module respectively, and is used to determine the output torque of the motor in the casting machine according to the variance of the pouring speed of the molten metal, or to determine the tension of the chain in the demolding machine according to the average demolding time of the initial sand mold, and to determine the circulation rate of cooling water according to the number of pores on the surface of the finished sand mold.

[0032] Compared with the prior art, the beneficial effect of the present invention lies in that the method of the present invention adjusts the motor output torque in the casting machine according to the variance of the pouring speed of the molten metal. Since the bearings of the tilting mechanism of the ladle in the casting equipment are worn after long-term use, the transmission shaft rotates unsmoothly, resulting in the tilting speed being out of control, thereby making the casting speed too fast. By increasing the motor output torque in the casting machine, the rotational resistance increased by the bearing wear can be overcome, ensuring that the transmission shaft can rotate normally, and the tilting mechanism of the ladle can operate according to the set action. The tension of the chain in the demolding machine is adjusted according to the average demolding time of the initial sand mold. Since the chain and sprocket in the demolding mechanism are worn after long-term use, the chain becomes longer and the sprocket tooth shape changes, resulting in a decrease in transmission accuracy and over-demolding. Jamming and slipping may occur during the casting process. By increasing the tension of the chain in the demolding machine, the chain can be better fitted to the sprocket teeth, increasing the meshing area and friction between the chain and the sprocket, thereby improving the accuracy and stability of the transmission and reducing the occurrence of jamming and slipping. The circulation rate of the cooling water is adjusted according to the number of pores on the surface of the finished sand mold. Since the cooling water used to cool the casting generates a large amount of water vapor during the evaporation process, it is not discharged from the workshop in time, which increases the humidity in the workshop, causing part of the water vapor during casting to form gas, forming pores and sand holes on the surface of the casting. By reducing the circulation rate of the cooling water, the evaporation of the cooling water can be reduced, thereby reducing the water vapor content and humidity in the workshop, reducing the formation of pores and sand holes on the surface of the casting, and improving the casting stability of the sand mold.

[0033] Furthermore, the method of the present invention adjusts the output torque of the motor in the casting machine by setting a preset first variance and a preset second variance. Since the bearings of the tilting mechanism of the ladle in the casting equipment are worn after long-term use, the transmission shaft rotates unsmoothly, resulting in a tilting speed that is out of control, thereby causing the casting speed to be too fast. By increasing the output torque of the motor in the casting machine, the rotational resistance increased by the bearing wear can be overcome, ensuring that the transmission shaft can rotate normally, and the ladle tilting mechanism can operate according to the set action, further improving the casting stability of the sand mold.

[0034] Furthermore, the method of the present invention adjusts the tension of the chain in the demolding machine by setting a preset first demolding time and a preset second demolding time. Since the chain and sprocket in the demolding mechanism wear out after long-term use, the chain becomes longer and the sprocket tooth shape changes, resulting in a decrease in transmission accuracy. Jamming and slipping may occur during the demolding process. By increasing the tension of the chain in the demolding machine, the chain can better fit the sprocket teeth, increasing the meshing area and friction between the chain and the sprocket, thereby improving the accuracy and stability of the transmission, reducing the occurrence of jamming and slipping, and further improving the casting stability of the sand mold.

[0035] Furthermore, the method of the present invention adjusts the circulation rate of cooling water by setting a preset number. Since the cooling water used to cool the casting generates a large amount of water vapor during evaporation, it is not discharged from the workshop in time, which increases the humidity in the workshop, causing part of the water vapor during casting to form gas, forming pores and sand holes on the surface of the casting. By reducing the circulation rate of cooling water, the evaporation amount of cooling water can be reduced, thereby reducing the water vapor content and humidity in the workshop, reducing the formation of pores and sand holes on the surface of the casting, and further improving the casting stability of the sand mold. BRIEF DESCRIPTION OF THE DRAWINGS

[0036] Figure 1 The present invention is an overall flow chart of a sand casting method for a gear seat according to an embodiment of the present invention;

[0037] Figure 2 The overall structural block diagram of the sand casting system for the gear seat according to the embodiment of the present invention;

[0038] Figure 3 The present invention is a logic flow chart of a sand casting method for a gear seat according to an embodiment of the present invention;

[0039] Figure 4 The present invention is a specific flow chart of a process for adjusting the output torque of a motor in a casting machine in a sand casting method for a gear seat according to an embodiment of the present invention. DETAILED DESCRIPTION

[0040] In order to make the objects and advantages of the present invention more clearly understood, the present invention is further described below in conjunction with embodiments; it should be understood that the specific embodiments described herein are only used to explain the present invention and are not used to limit the present invention.

[0041] The preferred embodiments of the present invention are described below with reference to the accompanying drawings. It should be understood by those skilled in the art that these embodiments are only used to explain the technical principles of the present invention and are not intended to limit the protection scope of the present invention.

[0042] It should be noted that, in the description of the present invention, terms such as "up", "down", "left", "right", "inside" and "outside" indicating directions or positional relationships are based on the directions or positional relationships shown in the drawings. This is merely for the convenience of description and does not indicate or imply that the device or element must have a specific orientation, be constructed and operated in a specific orientation. Therefore, it cannot be understood as a limitation on the present invention.

[0043] In addition, it should be noted that in the description of the present invention, unless otherwise clearly specified and limited, the terms "installed", "connected", and "connected" should be understood in a broad sense, for example, it can be a fixed connection, a detachable connection, or an integral connection; it can be a mechanical connection or an electrical connection; it can be a direct connection, or it can be indirectly connected through an intermediate medium, or it can be the internal communication of two components. For those skilled in the art, the specific meanings of the above terms in the present invention can be understood according to specific circumstances.

[0044] See also Figure 1 , Figure 2 , Figure 3 as well as Figure 4 As shown, they are respectively an overall flow chart, an overall structural block diagram, a logic flow chart, and a specific flow chart of the process of adjusting the output torque of the motor in the casting machine of the sand casting method and system for the gear seat of the embodiment of the present invention. The sand casting method for the gear seat of the present invention comprises:

[0045] Step S1, placing a sand core having the same shape as the gear seat into a core box, filling and surrounding the sand core with wet sand, melting ferrous metal to output molten metal, and using a pouring machine to pour the molten metal into the core box;

[0046] Step S2, cooling the core box by circulating cooling water, demolding the core box by using a demolding machine to output an initial sand mold, and successively performing residue removal and surface finishing operations on the initial sand mold to output a finished sand mold;

[0047] Step S3, obtaining the pouring speed of the molten metal in a plurality of pouring cycles;

[0048] Step S4, determining the casting stability of the sand mold based on the variance of the pouring speed of the molten metal;

[0049] Step S5, if the casting stability does not meet the requirements, adjusting the output torque of the motor in the pouring machine, or determining the casting reliability of the finished sand mold based on the average demolding time of the initial sand mold;

[0050] Step S6, if the casting reliability does not meet the requirements, the tension of the chain in the demolding machine is adjusted, or the circulation rate of the cooling water is adjusted based on the number of pores on the surface of the finished sand mold.

[0051] Specifically, ferrous metals include iron, steel, manganese and chromium.

[0052] Specifically, the initial sand mold is characterized by a rough surface, errors in shape, and residues on the surface.

[0053] Specifically, the finished sand mold is characterized by standard shape, smooth surface and flat surface.

[0054] In implementation, the method of the present invention adjusts the motor output torque in the casting machine according to the variance of the pouring speed of the molten metal. Since the bearings of the tilting mechanism of the ladle in the casting equipment are worn after long-term use, the transmission shaft rotates unsmoothly, resulting in a loss of control of the tilting speed, which makes the casting speed too fast. By increasing the motor output torque in the casting machine, the rotational resistance increased by the bearing wear can be overcome, ensuring that the transmission shaft can rotate normally, and the tilting mechanism of the ladle can operate according to the set action. The tension of the chain in the demolding machine is adjusted according to the average demolding time of the initial sand mold. Since the chain and sprocket in the demolding mechanism are worn after long-term use, the chain becomes longer and the sprocket tooth shape changes, resulting in a decrease in transmission accuracy, and jamming may occur during the demolding process. The phenomenon of jamming and slipping can be solved by increasing the tension of the chain in the demolding machine, which can make the chain fit the sprocket teeth better, increase the meshing area and friction between the chain and the sprocket, thereby improving the accuracy and stability of the transmission, and reducing the occurrence of jamming and slipping. The circulation rate of cooling water is adjusted according to the number of pores on the surface of the finished sand mold. Since the cooling water used to cool the casting produces a large amount of water vapor during the evaporation process, it is not discharged from the workshop in time, which increases the humidity in the workshop, causing part of the water vapor during casting to form gas, forming pores and sand holes on the surface of the casting. By reducing the circulation rate of cooling water, the evaporation of cooling water can be reduced, thereby reducing the water vapor content and humidity in the workshop, reducing the formation of pores and sand holes on the surface of the casting, and improving the casting stability of the sand mold.

[0055] Specifically, determining the casting stability of the sand mold includes:

[0056] Obtaining the pouring speed of the molten metal in a number of pouring cycles, and calculating the variance of the pouring speed of the molten metal;

[0057] Comparing the variance of the pouring speed of the molten metal with a preset first variance;

[0058] If the variance of the pouring speed of the molten metal is greater than the preset first variance, it is determined that the casting stability of the sand mold does not meet the requirements.

[0059] Specifically, determining the casting reliability of the finished sand mold includes:

[0060] Comparing the variance of the pouring speed of the molten metal with the preset first variance and the preset second variance respectively;

[0061] If the variance of the pouring speed of the molten metal is greater than the preset first variance and less than or equal to the preset second variance, it is preliminarily determined that the casting reliability of the finished sand mold does not meet the requirements, and whether the casting reliability of the finished sand mold meets the requirements is evaluated based on the average demolding time of the initial sand mold.

[0062] It can be understood that the three intervals divided by the preset first variance and the preset second variance correspond to three situations respectively:

[0063] The first interval is that the variance of the pouring speed of the molten metal is less than or equal to the preset first variance, and the corresponding situation is: determining that the casting stability of the sand mold meets the requirements;

[0064] The second interval is when the variance of the pouring speed of the molten metal is greater than the preset first variance and less than or equal to the preset second variance. The corresponding situation is: due to the wear of the chain and sprocket in the demolding mechanism after long-term use, the chain becomes longer and the sprocket tooth shape changes, resulting in a decrease in transmission accuracy, and jamming and slipping may occur during the demolding process;

[0065] The third interval is when the variance of the pouring speed of the molten metal is greater than the preset second variance. The corresponding situation is: due to the wear of the bearings of the tilting mechanism of the ladle in the pouring equipment after long-term use, the transmission shaft rotates unsmoothly, resulting in uncontrolled tilting speed, which makes the pouring speed too fast.

[0066] In practice, the preset first variance is generally selected in the range of [0.2 (kg / s) 2 , 0.4(kg / s) 2 ], the preset second variance is generally selected in the range of [0.5 (kg / s) 2 , 0.7(kg / s) 2 ].

[0067] Preferably, the preferred embodiment of the preset first variance is 0.3 (kg / s) 2 , the preferred embodiment of the preset second variance is 0.6 (kg / s) 2 .

[0068] Specifically, the variance of the pouring speed of the molten metal is the variance of the pouring speed of the molten metal within several pouring cycles. The calculation method of the variance of the pouring speed of the molten metal is a conventional technical means well known to those skilled in the art. Therefore, the calculation process of the variance of the pouring speed of the molten metal will not be repeated here.

[0069] In implementation, the method of the present invention determines the casting stability of the sand mold by setting a preset first variance and a preset second variance, thereby reducing the impact of the reduced casting accuracy of the sand mold due to inaccurate determination of the casting stability of the sand mold, and further improving the casting stability of the sand mold.

[0070] Specifically, adjusting the output torque of the motor in the casting machine includes:

[0071] Comparing the variance of the pouring speed of the molten metal with the preset second variance;

[0072] If the variance of the pouring speed of the molten metal is greater than a preset second variance, the output torque of the motor in the pouring machine is increased.

[0073] Specifically, the increase range of the output torque of the motor in the casting machine is determined by the difference between the variance of the casting speed of the molten metal and a preset second variance.

[0074] Specifically, the difference between the variance of the pouring speed of the molten metal and the preset second variance is 0.2 (kg / s) 2 When the difference between the variance of the pouring speed of the molten metal and the preset second variance exceeds 0.2 (kg / s), the motor output torque in the pouring machine increases to 1.1 times of the original value. 2 When the pressure is increased to 1.1 times of the original pressure, the pressure will be increased by 0.2 (kg / s) 2 , the motor output torque in the casting machine increases by 1N · m, for example, the difference between the variance of the pouring speed of the molten metal and the preset second variance is 0.6 (kg / s) 2 , the motor output torque in the current casting machine is 20N · m, the motor output torque in the enlarged casting machine is 20×1.1+1×2=24N · m.

[0075] In implementation, the method of the present invention adjusts the output torque of the motor in the casting machine by setting a preset first variance and a preset second variance. Since the bearings of the tilting mechanism of the ladle in the casting equipment are worn after long-term use, the transmission shaft rotates unsmoothly, resulting in a tilting speed that is out of control, thereby causing the casting speed to be too fast. By increasing the output torque of the motor in the casting machine, the rotational resistance increased by the bearing wear can be overcome, ensuring that the transmission shaft can rotate normally, and the ladle tilting mechanism can operate according to the set action, further improving the casting stability of the sand mold.

[0076] Specifically, adjusting the tension of the chain in the demoulding machine includes:

[0077] Obtaining the demolding time of the initial sand mold in several demolding cycles, and calculating the average demolding time of the initial sand mold;

[0078] Comparing the average demolding time of the initial sand mold with the preset first demolding time and the preset second demolding time respectively;

[0079] If the average demolding time of the initial sand mold is longer than the preset first demolding time, it is determined that the casting reliability of the finished sand mold does not meet the requirements;

[0080] If the average demolding time of the initial sand mold is greater than the preset first demolding time and less than or equal to the preset second demolding time, increasing the tension of the chain in the demolding machine;

[0081] If the average demolding time of the initial sand mold is greater than the preset second demolding time, it is preliminarily determined that the environmental stability of the sand casting does not meet the requirements, and whether the environmental stability of the sand casting meets the requirements is determined based on the number of pores on the surface of the finished sand mold.

[0082] It can be understood that the three intervals divided by the preset first demolding time and the preset second demolding time correspond to three situations respectively:

[0083] The first interval is that the average demolding time of the initial sand mold is less than or equal to the preset first demolding time, and the corresponding situation is: determining that the casting reliability of the finished sand mold meets the requirements;

[0084] The second interval is when the average demolding time of the initial sand mold is greater than the preset first demolding time and less than or equal to the preset second demolding time. The corresponding situation is: due to the wear of the chain and sprocket in the demolding mechanism after long-term use, the chain becomes longer and the sprocket tooth shape changes, resulting in a decrease in transmission accuracy, and jamming and slipping may occur during the demolding process;

[0085] The third interval is when the average demolding time of the initial sand mold is longer than the preset second demolding time. The corresponding situation is: since the cooling water used to cool the casting generates a large amount of water vapor during evaporation, it is not discharged from the workshop in time, causing the humidity in the workshop to increase, resulting in part of the water vapor during casting forming gas, forming pores and sand holes on the surface of the casting.

[0086] In practice, the preset first demolding time is generally selected in the range of [1.5min, 2.5min], and the preset second demolding time is generally selected in the range of [2.6min, 3.6min].

[0087] Preferably, the preferred embodiment of the preset first demoulding time length is 2 minutes, and the preferred embodiment of the preset second demoulding time length is 3 minutes.

[0088] Specifically, the average demolding time of the initial sand mold is the ratio of the total demolding time of the initial sand mold in a number of demolding cycles to the number of demolding cycles.

[0089] In implementation, the method of the present invention determines the casting reliability of the finished sand mold by setting a preset first demolding time and a preset second demolding time, thereby reducing the impact of the reduced casting stability of the sand mold due to inaccurate determination of the casting reliability of the finished sand mold, and further improving the casting stability of the sand mold.

[0090] Specifically, the increase in the tension of the chain in the demolding machine is determined by the difference between the average demolding time of the initial sand mold and the preset first demolding time.

[0091] Specifically, when the difference between the average demolding time of the initial sand mold and the preset first demolding time is within 1 minute, the tension of the chain in the demolding machine is increased to 1.2 times of the original value; when the difference between the average demolding time of the initial sand mold and the preset first demolding time exceeds 1 minute, on the basis of being increased to 1.2 times of the original value, the tension of the chain in the demolding machine is increased by 2mm for every 1 minute exceeding the original value. For example, the difference between the average demolding time of the initial sand mold and the preset first demolding time is 3 minutes. The current tension of the chain in the demolding machine is 10mm, and the increased tension of the chain in the demolding machine is 10×1.2+2×2=16mm.

[0092] In implementation, the method of the present invention adjusts the tension of the chain in the demolding machine by setting a preset first demolding time and a preset second demolding time. Since the chain and sprocket in the demolding mechanism wear out after long-term use, the chain becomes longer and the sprocket tooth shape changes, resulting in a decrease in transmission accuracy. Jamming and slipping may occur during the demolding process. By increasing the tension of the chain in the demolding machine, the chain can better fit the sprocket teeth, increasing the meshing area and friction between the chain and the sprocket, thereby improving the accuracy and stability of the transmission, reducing the occurrence of jamming and slipping, and further improving the casting stability of the sand mold.

[0093] Specifically, the circulation rate of the cooling water is adjusted, including:

[0094] Obtain the number of pores on the surface of the finished sand mold;

[0095] Comparing the number of pores on the surface of the finished sand mold with a preset number;

[0096] If the number of pores on the surface of the finished sand mold is greater than the preset number, it is determined that the environmental stability of the sand casting does not meet the requirements, and the circulation rate of the cooling water is reduced.

[0097] It can be understood that the two intervals divided by the preset number correspond to two situations:

[0098] The first interval is that the number of pores on the surface of the finished sand mold is less than or equal to the preset number, and the corresponding situation is: it is determined that the environmental stability of the sand casting meets the requirements;

[0099] The second interval is that the number of pores on the surface of the finished sand mold is greater than the preset number. The corresponding situation is: since the cooling water used to cool the casting generates a large amount of water vapor during evaporation, it is not discharged from the workshop in time, causing the humidity in the workshop to increase, resulting in part of the water vapor during casting forming gas, forming pores and sand holes on the surface of the casting.

[0100] In practice, the preset number is generally selected in the range of [2 pieces / cm 2 , 4 pieces / cm 2 ].

[0101] Preferably, the preset number is 3 pieces / cm 2 .

[0102] In implementation, the method of the present invention determines the environmental stability of sand casting by setting a preset number, thereby reducing the impact of the reduced casting stability of the sand mold due to inaccurate determination of the environmental stability of the sand casting, and further improving the casting stability of the sand mold.

[0103] Specifically, the reduction range of the circulation rate of the cooling water is determined by the difference between the number of pores on the surface of the finished sand mold and a preset number.

[0104] Specifically, the difference between the number of pores on the surface of the finished sand mold and the preset number is 2 pores / cm 2 When the difference between the number of pores on the surface of the finished sand mold and the preset number exceeds 2 / cm 2 When the number of cells exceeds 1 / cm, the number of cells will be reduced to 0.9 times of the original value. 2 , the cooling water circulation rate is reduced by 0.5L / min. For example, the difference between the number of pores on the surface of the finished sand mold and the preset number is 4 / cm 2 , the current cooling water circulation rate is 10L / min, and the reduced cooling water circulation rate is 10×0.9-0.5×2=8L / min.

[0105] In implementation, the method of the present invention adjusts the circulation rate of cooling water by setting a preset number. Since the cooling water used to cool the casting generates a large amount of water vapor during evaporation, it is not discharged from the workshop in time, which increases the humidity in the workshop, causing part of the water vapor during casting to form gas, forming pores and sand holes on the surface of the casting. By reducing the circulation rate of cooling water, the evaporation amount of cooling water can be reduced, thereby reducing the water vapor content and humidity in the workshop, reducing the formation of pores and sand holes on the surface of the casting, and further improving the casting stability of the sand mold.

[0106] A sand casting system for a gear seat, comprising:

[0107] A casting module, used for casting a sand core using a core box to output a finished sand mold, comprising a pouring unit for pouring the sand core to output a casting, a cooling unit connected to the pouring unit for cooling the casting, a demolding unit connected to the cooling unit for demolding the cooled casting to output an initial sand mold, and a trimming unit connected to the demolding unit for trimming the initial sand mold to output the finished sand mold;

[0108] Wherein, the pouring unit comprises a pouring machine for pouring the sand core, and the demoulding unit is a demoulding machine;

[0109] A detection module connected to the casting module, comprising a flow sensor connected to the pouring machine for detecting a pouring speed and a visual sensor for detecting the number of pores on the surface of the finished sand mold;

[0110] A control module is connected to the casting module and the detection module respectively, and is used to determine the output torque of the motor in the casting machine according to the variance of the pouring speed of the molten metal, or to determine the tension of the chain in the demolding machine according to the average demolding time of the initial sand mold, and to determine the circulation rate of cooling water according to the number of pores on the surface of the finished sand mold.

[0111] Specifically, the pouring unit also includes:

[0112] Core box, used to hold sand cores and wet sand;

[0113] A furnace used to melt ferrous metals into molten metal.

[0114] Specifically, the cooling unit includes:

[0115] Water tank, used to store cooling water;

[0116] A delivery pipe connected to the water tank for delivering the cooling water;

[0117] A valve is connected to the delivery pipe and is used to control the circulation rate of the cooling water.

[0118] Specifically, the trimming unit includes:

[0119] A cleaning machine to remove sand residue from the surface of the initial sand mold;

[0120] A grinding machine is used to grind the surface of the initial sand mold.

[0121] So far, the technical solutions of the present invention have been described in conjunction with the preferred embodiments shown in the accompanying drawings. However, it is easy for those skilled in the art to understand that the protection scope of the present invention is obviously not limited to these specific embodiments. Without departing from the principle of the present invention, those skilled in the art can make equivalent changes or substitutions to the relevant technical features, and the technical solutions after these changes or substitutions will fall within the protection scope of the present invention.

Claims

1. A sand casting method for a gear seat, characterized in that: include: Putting a sand core having the same shape as the gear seat into a core box, filling and surrounding the sand core with wet sand, melting the ferrous metal to output molten metal, and pouring the molten metal into the core box using a pouring machine; Cooling the core box by circulating cooling water, demoulding the core box by using a demoulding machine to output an initial sand mold, and successively performing residue removal and surface finishing operations on the initial sand mold to output a finished sand mold; Obtaining the pouring speed of molten metal in several pouring cycles; Determining the casting stability of the sand mold based on the variance of the pouring speed of the molten metal; If the casting stability does not meet the requirements, the output torque of the motor in the pouring machine is adjusted, or the casting reliability of the finished sand mold is determined based on the average demolding time of the initial sand mold; If the casting reliability does not meet the requirements, the tension of the chain in the demolding machine is adjusted, or the circulation rate of the cooling water is adjusted based on the number of pores on the surface of the finished sand mold.

2. The sand casting method for a gear seat according to claim 1, characterized in that: Determining the casting stability of the sand mold, including: comparing the variance of the pouring speed of the molten metal with a preset first variance; If the variance of the pouring speed of the molten metal is greater than the preset first variance, it is determined that the casting stability of the sand mold does not meet the requirements.

3. The sand casting method for a gear seat according to claim 2, characterized in that: Determining the casting reliability of the finished sand mold, including: Comparing the variance of the pouring speed of the molten metal with the preset first variance and the preset second variance respectively; If the variance of the pouring speed of the molten metal is greater than the preset first variance and less than or equal to the preset second variance, it is preliminarily determined that the casting reliability of the finished sand mold does not meet the requirements, and whether the casting reliability of the finished sand mold meets the requirements is evaluated based on the average demolding time of the initial sand mold.

4. The sand casting method for a gear seat according to claim 3, characterized in that: The output torque of the motor in the casting machine is adjusted, including: Comparing the variance of the pouring speed of the molten metal with the preset second variance; If the variance of the pouring speed of the molten metal is greater than a preset second variance, the output torque of the motor in the pouring machine is increased.

5. The sand casting method for a gear seat according to claim 4, characterized in that: The increase range of the output torque of the motor in the casting machine is determined by the difference between the variance of the casting speed of the molten metal and a preset second variance.

6. The sand casting method for a gear seat according to claim 5, characterized in that: The tension of the chain in the die-pulling machine is adjusted, including: The average demolding time of the initial sand mold is compared with the preset first demolding time and the preset second demolding time respectively; If the average demolding time of the initial sand mold is longer than the preset first demolding time, it is determined that the casting reliability of the finished sand mold does not meet the requirements; If the average demolding time of the initial sand mold is greater than the preset first demolding time and less than or equal to the preset second demolding time, increasing the tension of the chain in the demolding machine; If the average demolding time of the initial sand mold is greater than the preset second demolding time, it is preliminarily determined that the environmental stability of the sand casting does not meet the requirements, and whether the environmental stability of the sand casting meets the requirements is determined based on the number of pores on the surface of the finished sand mold.

7. The sand casting method for a gear seat according to claim 6, characterized in that: The increase in tension of the chain in the demolding machine is determined by the difference between the average demolding time of the initial sand mold and the preset first demolding time.

8. The sand casting method for a gear seat according to claim 7, characterized in that: The circulation rate of the cooling water is adjusted, including: Compare the number of pores on the surface of the finished sand mold with the preset number; If the number of pores on the surface of the finished sand mold is greater than the preset number, it is determined that the environmental stability of the sand casting does not meet the requirements, and the circulation rate of the cooling water is reduced.

9. The sand casting method for a gear seat according to claim 8, characterized in that: The reduction range of the circulation rate of the cooling water is determined by the difference between the number of pores on the surface of the finished sand mold and a preset number.

10. A sand casting system for a gear seat using the sand casting method for a gear seat according to any one of claims 1 to 9, characterized in that: include: A casting module, used for casting a sand core using a core box to output a finished sand mold, comprising a pouring unit for pouring the sand core to output a casting, a cooling unit connected to the pouring unit for cooling the casting, a demolding unit connected to the cooling unit for demolding the cooled casting to output an initial sand mold, and a trimming unit connected to the demolding unit for trimming the initial sand mold to output the finished sand mold; Wherein, the pouring unit comprises a pouring machine for pouring the sand core, and the demoulding unit is a demoulding machine; A detection module connected to the casting module, comprising a flow sensor connected to the pouring machine for detecting a pouring speed and a visual sensor for detecting the number of pores on the surface of the finished sand mold; A control module is connected to the casting module and the detection module respectively, and is used to determine the output torque of the motor in the casting machine according to the variance of the pouring speed of the molten metal, or to determine the tension of the chain in the demolding machine according to the average demolding time of the initial sand mold, and to determine the circulation rate of cooling water according to the number of pores on the surface of the finished sand mold.

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