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CN-122007338-A - Sand mould 3D printing-based sand-box-free molding method

CN122007338ACN 122007338 ACN122007338 ACN 122007338ACN-122007338-A

Abstract

The invention relates to a sand-mold-3D printing-based sand-free molding method, which relates to the technical field of casting molding, and comprises the steps of longitudinally splitting a 3D printing sand mold into a plurality of parts, thickening the outer side walls of a bottom sand mold, designing locking grooves at the thickened parts of the two symmetrical outer side walls of the bottom sand mold, wherein each locking groove comprises a vertical section penetrating through the top surface of the bottom sand mold and a limiting section with the middle part connected with the bottom end of the bottom sand mold, a box tightening rod with the bottom end matched with the locking groove in shape is arranged in each locking groove, a box tightening frame is arranged above a top sand mold, the top ends of all the box tightening rods penetrate through the box tightening frame and are screwed with box tightening nuts, and the bottom sand mold, the top sand mold and all the middle sand mold are locked into a combined mold, so that the problem that the assembly of the 3D printing sand mold is difficult under the condition of no sand mold which can completely cover the sand mold is solved, and the problem that the sand mold is completely covered can increase the manufacturing cost and prolong the manufacturing period of the sand mold is solved.

Inventors

  • LI PEISEN
  • MA ERBO
  • CHENG BO
  • WEI CHENGYU
  • HUANG DAOYANG
  • ZHANG YUEQI
  • CHENG HONGXUN
  • WANG WEIYONG
  • MENG LIQIN
  • NIU MENGMENG
  • CAO XIJUAN
  • WANG NAN
  • REN GUANGXIAO
  • HE YANXIA
  • WANG WENLI
  • SHEN ZHIPENG
  • WANG HAO
  • QUAN DENGHUI

Assignees

  • 山西江淮重工有限责任公司

Dates

Publication Date
20260512
Application Date
20260312

Claims (10)

  1. 1. Sand mold 3D printing-based sand-free molding method is characterized by comprising the following steps of: S1, designing a model, namely dividing a three-dimensional model of a sand mold into a bottom sand mold, a top sand mold, a plurality of middle sand molds and sand cores, wherein the outer side wall of the bottom sand mold is thickened, locking grooves are designed at thickened parts of two symmetrical outer side walls of the bottom sand mold, and each locking groove comprises a vertical section penetrating through the top surface of the bottom sand mold and a limiting section with the middle part connected with the bottom end of the bottom sand mold; S2, assembling preparation, namely 3D printing the bottom sand mold, the top sand mold, the middle sand mold and the sand core, prefabricating a box tightening rod, a box tightening frame and a box tightening nut, wherein the bottom end of the box tightening rod is matched with the locking groove; s3, assembling a sand mold, namely placing the bottom sand mold on a molding bottom plate, and coating box-assembling glue on the upper surface of the bottom sand mold; Stacking the middle sand mold onto the bottom sand mold, positioning the sand cores in the middle sand mold in the stacking process, and coating mold closing glue on the parting surfaces of two adjacent middle sand molds; Coating a mold assembling glue on the upper surface of the uppermost middle sand mold, and closing the top sand mold; And the top ends of all the box tightening rods penetrate through the box tightening frames and then are screwed with the box tightening nuts to lock the bottom sand mold, the top sand mold and all the middle sand molds into a combined casting mold.
  2. 2. The sand mold 3D printing-based flaskless molding method according to claim 1, wherein a liquid lifting port, a horizontal runner and a first runner are sequentially designed on the bottom sand mold from bottom to top, a second runner communicated with the first runner is designed on the lowest middle sand mold, a gap runner communicated with the second runner and a cavity connected with the gap runner are designed on the rest middle sand mold, and a riser connected with the gap runner is designed on the bottom surface of the top sand mold.
  3. 3. The sand mold 3D printing-based flaskless molding method according to claim 2, wherein a mounting groove for accommodating a filter screen is formed in the upper surface of the bottom sand mold, the filter screen is located at the junction of the first sprue and the second sprue, and after the filter screen is placed in the mounting groove, a mold assembling glue is coated on the upper surface of the bottom sand mold.
  4. 4. The sand-mold-3D-printing-based flaskless molding method according to claim 2, wherein in the step S2, a box with an open top is prefabricated based on the model designed in the step S1, lifting hooks are arranged on two sides of the box, a liquid lifting through hole is formed in a bottom plate of the box, in the step S3, the bottom of the combined mold is placed in the box, a first sealing layer is arranged between the bottom surface of the combined mold and the bottom plate of the box, the liquid lifting through hole is communicated with the liquid lifting opening, sand and adhesive are filled between the box and the combined mold, the sand and the adhesive are hardened to form a sealed sand mold, and the top surface of the sealed sand mold is higher than half of the height of the lowest middle sand mold.
  5. 5. The sand mold 3D printing-based flaskless molding method according to any one of claims 1 to 4, wherein in the step S1, a limiting boss is designed on the bottom surface of the sand core, and a limiting groove matching the limiting boss is designed on the upper surface of the lowest middle sand mold; And in the step S3, after the box closing glue is coated in the limiting groove, the limiting boss is inserted into the limiting groove.
  6. 6. The sand mold 3D printing-based flaskless molding method according to any one of claims 1 to 4, wherein in the step S1, a frame-shaped seal groove is designed on a parting surface of two adjacent middle sand molds, and the parts of the middle sand molds for flowing metal liquid are all located at the inner sides of the seal groove; The metal sealing strip is prefabricated in the S2; And when stacking the middle sand mold in the step S3, coating mold closing glue on the surfaces of the metal sealing strips, partially inserting a plurality of the metal sealing strips into the sealing grooves below the middle sand mold parting surface in an end-to-end connection mode, stacking the middle sand mold with the lower surface coated with the mold closing glue on the middle sand mold embedded with the metal sealing strips, and embedding the rest parts of the metal sealing strips into the sealing grooves above the middle sand mold parting surface.
  7. 7. The sand mold 3D printing-based flaskless molding method according to claim 6, wherein in the step S1, a first boss is designed on the upper surface of the uppermost middle sand mold, a first groove is designed on the bottom surface of the top sand mold to match the first boss, a second boss is designed on the bottom surface of the lowermost middle sand mold, and a second groove is designed on the upper surface of the bottom sand mold to match the second boss.
  8. 8. The sand mold 3D printing-based sand mold forming method according to any one of claims 1 to 4, wherein two locking grooves symmetrically located on two sides of a bottom sand mold are one group, a plurality of groups of locking grooves are arranged, the same group of locking grooves correspond to one locking groove, two limiting grooves are respectively arranged at two ends of each locking groove, and two symmetrically installed box tightening rods move towards each other to enter the limiting grooves at two ends of the box tightening frame and then are screwed with the box tightening nuts.
  9. 9. The sand mold 3D printing-based flaskless molding method according to claim 8, wherein the box tightening frame comprises a bottom plate and two vertical plates molded on the upper surface of the bottom plate, the two vertical plates are respectively located at two side edges of the bottom plate, and the limiting groove is formed in the bottom plate.
  10. 10. The sand mold 3D printing-based flaskless molding method according to any one of claims 1 to 4, wherein in the step S1, two lifting lugs are symmetrically designed on the outer side of the bottom sand mold, the lifting lugs and the box tightening groove are respectively designed on different sides of the bottom sand mold, two lifting lugs are symmetrically designed on the outer side of the top sand mold, and two lifting lugs are symmetrically designed on the outer side of the middle sand mold; and in the step S3, the lifting lug and the box tightening rod are respectively assembled on different sides of the combined casting mold.

Description

Sand mould 3D printing-based sand-box-free molding method Technical Field The invention relates to the technical field of casting molding, in particular to a sand-mold-3D printing-based sand-box-free molding method. Background The 3D printing is one kind of fast forming technology, and is one kind of technology of constructing object with powdered metal, plastic or other adhesive material based on digital model file in layer-by-layer printing mode. The 3D printing technology is mostly applied to printing of plastic products and printing of specific metal materials, but is just started in manufacturing of casting sand molds. The traditional sand mould manufacturing is to firstly manufacture the part wood mould or the metal mould, then manufacture the sand mould by taking the part wood mould or the metal mould as a prototype, so that the part wood mould and the metal mould can be modified or reworked in the initial production stage, such as when the process and the appearance are found to be changed in sand mould inspection, and the sand mould can be produced in batches after repeated verification is qualified, and the research and development period is longer. The 3D printing sand mold can save the step of processing the part wood mold or the metal mold, directly produce the sand mold, and is beneficial to shortening the research and development period of the sand mold. On the preparation of casting sand mould, because weight and volume are all great foundry goods, because its sand mould prints and eats sand volume big, 3D printing equipment often can't realize the integrative printing of its sand mould, only can split into the multipart printing respectively with the sand mould after the equipment as an organic whole. Currently, the assembly of the 3D printed sand mold usually needs to use a sand box, and for this purpose, the sand box capable of completely covering the sand mold needs to be additionally manufactured, which increases the manufacturing cost of the cast sand mold and prolongs the manufacturing period of the cast sand mold. Disclosure of Invention Aiming at the defects existing in the related art, the invention provides a sand-mold-3-D-printing-based sand-mold-free molding method, which is characterized in that a 3D printing sand mold is longitudinally split into a plurality of parts, the outer side walls of a bottom sand mold are thickened, locking grooves are designed at the thickened parts of the two symmetrical outer side walls of the bottom sand mold so as to be connected with a box tightening rod, and the parts of the 3D printing sand mold are locked into a combined mold by means of the matching of the box tightening rod, the box tightening frame and the box tightening nut, so that the problem that the 3D printing sand mold is difficult to assemble under the condition that a sand box capable of completely coating the sand mold is not available is solved, and the problem that the sand mold manufacturing cost and the manufacturing period of the sand mold can be increased by completely coating the sand box of the sand mold are solved. The invention provides a sand-free box forming method based on sand mould 3D printing, which comprises the following steps: S1, designing a model, namely dividing a three-dimensional model of a sand mold into a bottom sand mold, a top sand mold, a plurality of middle sand molds and sand cores, wherein the outer side wall of the bottom sand mold is thickened, locking grooves are designed at thickened parts of two symmetrical outer side walls of the bottom sand mold, and each locking groove comprises a vertical section penetrating through the top surface of the bottom sand mold and a limiting section with the middle part connected with the bottom end of the bottom sand mold; S2, assembling preparation, namely 3D printing the bottom sand mold, the top sand mold, the middle sand mold and the sand core, prefabricating a box tightening rod, a box tightening frame and a box tightening nut, wherein the bottom end of the box tightening rod is matched with the locking groove; s3, assembling a sand mold, namely placing the bottom sand mold on a molding bottom plate, and coating box-assembling glue on the upper surface of the bottom sand mold; Stacking the middle sand mold onto the bottom sand mold, positioning the sand cores in the middle sand mold in the stacking process, and coating mold closing glue on the parting surfaces of two adjacent middle sand molds; Coating a mold assembling glue on the upper surface of the uppermost middle sand mold, and closing the top sand mold; And the top ends of all the box tightening rods penetrate through the box tightening frames and then are screwed with the box tightening nuts to lock the bottom sand mold, the top sand mold and all the middle sand molds into a combined casting mold. In some embodiments, the bottom sand mold is sequentially provided with a liquid lifting port, a horizontal pouring gate and a first pouring gate from b