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CN-122007347-A - Hub rapid forming and casting process

CN122007347ACN 122007347 ACN122007347 ACN 122007347ACN-122007347-A

Abstract

The invention discloses a hub rapid molding casting process which comprises the steps of S1, manufacturing a sand core corresponding to the shape of a spoke lateral through hole, S2, preheating a side die, an upper die, a bottom die and the sand core of a hub die, S3, positioning and installing the sand core at a preset position of an inner cavity of the side die, S4, closing the die to form a casting cavity containing the sand core, S5, pouring molten metal into the cavity to wrap the sand core, S6, rapidly cooling key parts such as the hub upper ear after pouring, simultaneously applying sectional high pressure to the cavity through a liquid storage hopper for feeding, S7, opening the die after solidification, taking out a hub blank with the lateral through hole structure, and finally removing the sand core. According to the invention, the complex lateral through hole is directly formed in the casting link, so that a large amount of subsequent milling processing is omitted, the production cost is greatly reduced, the production efficiency is improved, and the overall mechanical property of the hub is ensured.

Inventors

  • SU DAN
  • XIANG YOUCHENG
  • WANG JUNHUA
  • LI JIAXIN
  • Cao Ruisong

Assignees

  • 江西荣恩轮毂制造有限公司

Dates

Publication Date
20260512
Application Date
20260302

Claims (9)

  1. 1. The hub rapid prototyping casting process is characterized by comprising the following steps of: S1, preparing a sand core, namely manufacturing the sand core with the shape consistent with that of the through hole according to the shape of the lateral through hole of the spoke part in the hub design drawing; S2, preheating the mould and the sand core, namely heating the side mould, the upper mould and the bottom mould of the hub mould and the sand core prepared in the step S1; s3, positioning the sand core, namely accurately installing and fixing the preheated sand core at a preset position in the inner cavity of the side die, corresponding to the side surface of the spoke, where a through hole is required to be formed; S4, die assembly, namely die assembly is carried out on a side die provided with a sand core, an upper die and a bottom die, and a casting cavity which contains the sand core and is used for forming a hub with a lateral through hole is formed after die assembly; S5, pouring, namely pouring molten metal liquid into the casting cavity from a pouring gate, filling the casting cavity with the molten metal liquid and wrapping the sand core; S6, after casting, rapidly cooling molten metal positioned on the upper lug of the hub formed in the casting cavity, and simultaneously, applying sectional high pressure to the molten metal stored in the liquid storage hopper through the gas pressurizing system to force the molten metal in the liquid storage hopper to sequentially feed the casting cavity, so that the full feeding of the upper lug of the hub is preferentially ensured; S7, opening the mould and cleaning sand, namely stopping pressurizing after the hub is completely solidified, opening the mould to take out a hub casting blank with a lateral through hole structure, and finally removing sand core materials in the hub casting to form a final lateral through hole.
  2. 2. The rapid hub molding and casting process according to claim 1, wherein in the step S2, the preheating temperature is controlled to be 650-710 ℃, and the preheating temperature of the sand core is not lower than 300 ℃.
  3. 3. The hub rapid prototyping casting process of claim 1 wherein in step S3, the sand core is positioned and fixed by a positioning pin, a positioning groove or a magnetic fixing device preset in the inner cavity of the side mold, so as to ensure that the sand core does not displace or float in the casting process.
  4. 4. The rapid prototyping casting process of claim 1 wherein in step S4, the temperature of the reservoir is independently controlled by a heating system to maintain the temperature of the reservoir at 650-710 ℃ prior to casting.
  5. 5. The hub rapid prototyping casting process of claim 1 wherein in step S5 the volume of molten metal poured is equal to the sum of the volume of the casting cavity and the volume required for the feed, wherein the feed volume is 6% -8% of the total volume of molten metal.
  6. 6. The rapid prototyping casting process of claim 1 wherein in step S6, the segmented high pressure is six-segment pressure, the pressure ranges from 0.5 KGF/cm2 to 6 KGF/cm2, the total duration of the pressure ranges from 180 seconds to 210 seconds, and the specific pressure versus time profile is adjusted according to the hub size and wall thickness.
  7. 7. The rapid prototyping casting process of claim 1 or 6 wherein in step S6, the sequential cooling and feeding process is performed by rapid cooling of the upper ear of the hub while simultaneously feeding at high pressure, followed by sequential cooling and feeding of the rim, spokes including the lateral through hole structure, wheel disc and wheel disc center.
  8. 8. The rapid prototyping casting process of claim 1 wherein in step S7, the sand core is removed by one or more of mechanical vibration cleaning, high pressure air blowing or solvent cleaning.
  9. 9. The hub rapid prototyping casting process of claim 1, wherein the molten metal is aluminum alloy liquid, and the casting temperature is 700-720 ℃.

Description

Hub rapid forming and casting process Technical Field The invention relates to the technical field of hub processing, in particular to a hub rapid forming and casting process. Background Hubs are critical safety components and important appearance parts of automobiles. Modern automobile hubs are increasingly designed with attention paid to light weight and attractive appearance, and many high-end or sports hubs are designed with complex three-dimensional hollowed-out structures at spoke parts so as to lighten weight, enhance heat dissipation and improve visual effects. Currently, the mainstream aluminum alloy hub production process faces a great challenge for such hubs with complex lateral (non-axial) through holes. The traditional integral gravity casting or low-pressure casting process cannot directly form a lateral suspension structure inside the closed die. Therefore, the common practice in the industry is to obtain a solid hub blank or a hub blank with only simple axial holes through casting, and then to use a multi-axis numerical control machine tool to mill the spoke part for a long time by using an expensive special forming tool, so as to gradually cut out complex three-dimensional hollowed-out through holes required by design. The process route of casting and CNC finish milling has the obvious defects of 1) high cost, high price of special cutters, high processing loss, long CNC processing time, high equipment occupation and energy consumption cost. 2) The efficiency is low, the time for milling a complex hollow spoke is long, and the production takt is restricted. 3) And the material waste is that a large amount of cast aluminum alloy is cut into scraps, and the material utilization rate is low. 4) Potential mechanical properties impact the cutting process may cut metal streamlines and create microscopic stresses on the machined surface that may theoretically have an adverse effect on the fatigue performance of the hub. Disclosure of Invention The invention aims to solve the problems of providing a hub rapid forming casting process, creatively combining a sand core casting concept with an advanced hub high-pressure sequential feeding casting process, and being capable of directly forming complex through holes on the side surfaces of spokes in the casting process, thereby omitting or greatly reducing subsequent CNC (computerized numerical control) processing procedures and achieving the aims of reducing cost, enhancing efficiency and improving quality. The invention provides a technical scheme for solving the problems, which is characterized in that the hub rapid forming and casting process comprises the following steps: S1, preparing a sand core, namely manufacturing the sand core with the shape consistent with that of the through hole according to the shape of the lateral through hole of the spoke part in the hub design drawing; S2, preheating the mould and the sand core, namely heating the side mould, the upper mould and the bottom mould of the hub mould and the sand core prepared in the step S1; s3, positioning the sand core, namely accurately installing and fixing the preheated sand core at a preset position in the inner cavity of the side die, corresponding to the side surface of the spoke, where a through hole is required to be formed; S4, die assembly, namely die assembly is carried out on a side die provided with a sand core, an upper die and a bottom die, and a casting cavity which contains the sand core and is used for forming a hub with a lateral through hole is formed after die assembly; S5, pouring, namely pouring molten metal liquid into the casting cavity from a pouring gate, filling the casting cavity with the molten metal liquid and wrapping the sand core; S6, after casting, rapidly cooling molten metal positioned on the upper lug of the hub formed in the casting cavity, and simultaneously, applying sectional high pressure to the molten metal stored in the liquid storage hopper through the gas pressurizing system to force the molten metal in the liquid storage hopper to sequentially feed the casting cavity, so that the full feeding of the upper lug of the hub is preferentially ensured; S7, opening the mould and cleaning sand, namely stopping pressurizing after the hub is completely solidified, opening the mould to take out a hub casting blank with a lateral through hole structure, and finally removing sand core materials in the hub casting to form a final lateral through hole. Preferably, in the step S2, the preheating temperature is controlled to be 650-710 ℃, and the preheating temperature of the sand core is not lower than 300 ℃. Preferably, in step S3, the sand core is positioned and fixed by a positioning pin, a positioning slot or a magnetic fixing device preset in the inner cavity of the side mold, so as to ensure that the sand core does not displace or float in the casting process. Preferably, in step S4, the temperature of the liquid storage hopper is independently contro