阅读说明：本技术 一种新型的主轴承盖铸造工艺 (Novel casting process for main bearing cap ) 是由 巢华军 倪国金 贡建平 吴勇军 邱建红 于 2019-10-23 设计创作，主要内容包括：本发明公开了一种新型的主轴承盖铸造工艺,所述铸造方法包括以下具体步骤,S1、按照铸造工艺图制作木模,将两主轴承盖毛坯平躺相连呈X形且与水平方向呈八度倾角制作成整体木模,所得木模正中固定于型板上,为便于起模,木模整体采用框架式,四周采用脱落式。本发明采用两毛坯连体铸造的方法,提高了生产效率,降低了生产成本,节省了专用工装,取代了机加工切割方式,提高了加工效率,避免了刀具磨损导致的成本增加,且通过控制铸造的工艺条件,能够解决大型发动机主轴承盖缩松缺陷问题,使得该类铸件的缩松得到改善,并显著减少金属材料消耗并保证产品质量,显著提高工艺出品率,实用性强,值得推广。(The invention discloses a novel main bearing cap casting process, which comprises the following specific steps of S1, manufacturing a wood pattern according to a casting process diagram, horizontally connecting two main bearing cap blanks to form an X shape, forming an octave inclination angle with the horizontal direction to manufacture an integral wood pattern, fixing the obtained wood pattern on a template in the center, and adopting a frame type wood pattern as a whole and a stripping type wood pattern at the periphery for facilitating pattern stripping. The invention adopts the method of two blanks for conjoined casting, improves the production efficiency, reduces the production cost, saves special tools, replaces a machining cutting mode, improves the processing efficiency, avoids the cost increase caused by the abrasion of a cutter, and can solve the problem of the shrinkage and loosening defect of the main bearing cover of the large-scale engine by controlling the casting process conditions, thereby improving the shrinkage and loosening of the castings, obviously reducing the consumption of metal materials and ensuring the product quality, obviously improving the process yield, having strong practicability and being worthy of popularization.)

1. The utility model provides a novel main bearing cap casting process which characterized in that: the casting method comprises the following specific steps:

s1, manufacturing a wood pattern according to a casting process diagram, flatly laying and connecting two main bearing cover blanks to form an X shape, forming an octave inclination angle with the horizontal direction to manufacture an integral wood pattern, fixing the center of the obtained wood pattern on a template, wherein the wood pattern is integrally frame-type and is separated from the periphery in order to facilitate pattern stripping;

s2, filling configured molding sand into the manufactured wood mold, tamping, scraping, and after the molding sand in the wood mold is hardened, pulling out the molding sand in the wood mold from the wood mold to form a sand core;

s3, adopting phenolic resin self-hardening sand for molding, wherein chromite sand is used in areas of a bearing hole and a riser, a single riser is arranged in the center of an upper plane at the joint of two main bearing cover blanks, a sprue seat is placed at a sprue gate when a group of main bearing covers are poured, the sprue gate is connected with the bottoms of the two main bearing cover blanks, a plurality of shape-following chills are connected with the bearing hole positions of the two main bearing cover blanks, and an exhaust hole is formed in the upper plane of the two main bearing cover blanks to complete the molding of an upper box and a lower box of a casting;

s4, drying the casting mould by hot air, and then finishing the pouring work;

s5, smelting molten metal by using an induction furnace, wherein the tapping temperature of the molten metal is controlled to be 1400-1500 ℃, the carbon equivalent in the molten iron is controlled to be 3.3-5.5%, and the pouring temperature is 1300-1350 ℃;

s6, performing shakeout, riser cutting, artificial aging, body performance sample extraction according to batches, shot blasting, grinding and heat treatment on the poured main bearing cap;

and S7, carrying out magnetic powder inspection on the surface of the casting, and then inspecting the body performance and appearance of the main bearing cap according to the pouring batch.

2. The novel main bearing cap casting process according to claim 1, wherein: and the upper casting box and the lower casting box are fastened by a mechanical method.

3. The novel main bearing cap casting process according to claim 1, wherein: the 24-hour tensile strength of the sand mold in the S3 is 2.5-2.8 MPa.

4. The novel main bearing cap casting process according to claim 1, wherein: and the time of the card box in the S3 is 15-22 h.

5. The novel main bearing cap casting process according to claim 1, wherein: and a filter plate is arranged in the sprue seat in the S3 process.

6. The novel main bearing cap casting process according to claim 1, wherein: the spacing between the two main bearing cap blanks in S1 is 42-66 mm.

Technical Field

The invention relates to the technical field of manufacturing of main bearing caps, in particular to a novel casting process of a main bearing cap.

Background

The main bearing cover is known to be one of important parts in diesel engine parts, is made of nodular cast iron (hereinafter referred to as nodular cast iron), is matched with an engine body, needs to bear large alternating impact load, has high quality requirement, does not allow welding repair, does not allow casting defects such as shrinkage cavities (looseness), air holes, slag inclusion, cracks and the like, and the like.

At present, the common main bearing cap casting process has the problems of high production cost and low yield, greatly influences the economic benefit of manufacturers, and solves the problems by urgently needing a novel main bearing cap casting process.

Disclosure of Invention

The invention aims to provide a novel main bearing cap casting process to solve the problems in the background technology.

In order to achieve the purpose, the invention provides the following technical scheme: a novel main bearing cap casting process comprises the following specific steps:

s1, manufacturing a wood pattern according to a casting process diagram, namely, flatly laying and connecting two main bearing cover blanks to form an X shape, forming an octave inclination angle with the horizontal direction to manufacture an integral wood pattern, fixing the center of the obtained wood pattern on a template, wherein the wood pattern is integrally frame-type and is separated from the periphery in order to facilitate pattern stripping;

s2, filling configured molding sand into the manufactured wood mold, tamping, scraping, and after the molding sand in the wood mold is hardened, pulling out the molding sand in the wood mold from the wood mold to form a sand core;

s3, adopting phenolic resin self-hardening sand for modeling, wherein ferrochrome ore is used in areas of a bearing hole and a riser, a single riser is arranged in the center of an upper plane at the joint of two main bearing cover blanks, a sprue seat is placed at a sprue gate when a group of main bearing covers are poured, the sprue gate is connected with the bottoms of the two main bearing cover blanks, a plurality of conformal chills are connected with the bearing hole of the two main bearing cover blanks, and an exhaust hole is formed in the upper plane of the two main bearing cover blanks to complete the modeling of an upper box and a lower box of a casting;

s4, drying the casting mould by hot air, and then finishing the pouring work;

s5, smelting molten metal by using an induction furnace, wherein the tapping temperature of the molten metal is controlled to be 1400-1500 ℃, the carbon equivalent in the molten iron is controlled to be 3.3-5.5%, and the pouring temperature is 1300-1350 ℃;

s6, performing shakeout, riser cutting, artificial aging, body performance sample extraction according to batches, shot blasting, grinding and heat treatment on the poured main bearing cap;

and S7, carrying out magnetic powder inspection on the surface of the casting, and then inspecting the body performance and appearance of the main bearing cap according to the pouring batch.

Preferably, the upper casting box and the lower casting box are fastened by a mechanical method.

Preferably, the 24-hour tensile strength of the sand mold in S3 is 2.5-2.8 MPa.

Preferably, the carton clamping time in the S3 is 15-22 h.

Preferably, a filter is arranged inside the sprue seat in the step S3.

Preferably, the spacing between the two main bearing cap blanks in S1 is 42-66 mm.

Compared with the prior art, the invention has the beneficial effects that:

the invention adopts the method of conjoined casting of two blanks, improves the production efficiency, reduces the production cost, saves special tools, replaces a machining cutting mode, improves the processing efficiency, avoids the cost increase caused by the abrasion of a cutter, and can control the casting process condition to realize the combined casting of two blanks

Detailed Description

The technical solutions in the embodiments of the present invention will be clearly and completely described below, and it is obvious that the described embodiments are only a part of the embodiments of the present invention, and not all embodiments. All other embodiments, which can be obtained by a person skilled in the art without any inventive step based on the embodiments of the present invention, are within the scope of the present invention.