阅读说明：本技术 一种压缩机用上法兰无冒口浇注系统以及上法兰的生产工艺 (Riser-free pouring system for upper flange for compressor and production process of upper flange ) 是由 贾平凡 乔胜之 王光禹 贾玉珍 哈党明 于 2019-11-11 设计创作，主要内容包括：本发明属于铸件加工领域,其公开了一种压缩机用上法兰无冒口浇注系统,包括砂型铸模,所述砂型铸模内设有多个与上法兰形状匹配的型腔,所述砂型铸模内设有依次连接的浇口杯、横浇道、竖浇道、内浇口,所述内浇口与型腔连通；所述内浇口为楔形薄片结构；所述型腔上连接有排气条；所述竖浇道上设有减压槽,所述型腔中设有多个与上法兰的轮辐对应的辐条槽；至少一条辐条槽和内浇口正对；所述减压槽位于上下布置的两行型腔之间。该系统能够控制热节圆的位置,使铁水充型稳定、避免湍流。同时,还提供一种生产工艺,通过改进了配方,实现了产品质量的综合提高。(The invention belongs to the field of casting processing, and discloses a riser-free pouring system for an upper flange of a compressor, which comprises a sand mold, wherein a plurality of cavities matched with the upper flange in shape are arranged in the sand mold, a sprue cup, a horizontal pouring channel, a vertical pouring channel and an inner pouring gate which are sequentially connected are arranged in the sand mold, and the inner pouring gate is communicated with the cavities; the inner gate is of a wedge-shaped thin sheet structure; the cavity is connected with an exhaust strip; the vertical pouring gate is provided with a pressure reduction groove, and the cavity is internally provided with a plurality of spoke grooves corresponding to spokes of the upper flange; the at least one spoke groove is opposite to the inner sprue; the pressure reduction groove is positioned between two rows of cavities which are arranged up and down. The system can control the position of the thermal pitch circle, so that the molten iron filling is stable and turbulence is avoided. Meanwhile, a production process is also provided, and the comprehensive improvement of the product quality is realized by improving the formula.)

1. A riser-free pouring system for an upper flange of a compressor comprises a sand casting mold, wherein a plurality of cavities matched with the upper flange in shape are arranged in the sand casting mold, a pouring cup, a cross gate, a vertical gate and an inner gate which are sequentially connected are arranged in the sand casting mold, and the inner gate is communicated with the cavities; the method is characterized in that the inner sprue is of a wedge-shaped thin sheet structure; the cavity is connected with an exhaust strip; the vertical pouring gate is provided with a pressure reduction groove, and the cavity is internally provided with a plurality of spoke grooves corresponding to spokes of the upper flange; the at least one spoke groove is opposite to the inner sprue; the pressure reduction groove is positioned between two rows of cavities which are arranged up and down.

2. The upper flange riser-free gating system for the compressor according to claim 1, wherein the tail end of the runner is wedge-shaped.

3. The upper flange riser-less gating system for a compressor of claim 1, wherein the horizontal runner and the vertical runner are connected by a dovetail joint.

4. The upper flange riser-less gating system for a compressor according to any one of claims 1 to 3, wherein a ratio of a cross-sectional area of the runner, a cross-sectional area of the dovetail joint portion, a cross-sectional area of the sprue, and a cross-sectional area of a maximum cross-sectional area of the ingate is 1:0.8:1: 1.05.

5. An upper flange riser-less gating system for a compressor according to any one of claims 1 to 3, wherein a ratio of a sectional area of the decompression groove to a sectional area of the vertical runner is 0.45: 1.

6. A process for producing an upper flange for a compressor, characterized by casting using the casting system according to any one of claims 1 to 5; the components of the poured molten iron are as follows:

c: 3.35-3.45%, Si: 2.30-2.40%, Mn: 0.65-0.80%, P < 0.06%, S: 0.06-0.10%, trace Sb or Sn, and the balance of iron.

7. The upper flange production process for the compressor as claimed in claim 6, wherein the smelting temperature of the poured molten iron is 1480-1520 ℃; standing for 5-10min after smelting the molten iron; the temperature of molten iron is 1400-1420 ℃ during pouring.

8. The process for producing the upper flange for the compressor as claimed in claim 6, wherein the temperature of the molten iron is 1400-1420 ℃ during the casting; the quantity of molten iron discharged from each ladle is controlled to be 670 plus or minus 10kg, and the pouring time of each ladle is less than or equal to 8 minutes.

Technical Field

The invention relates to the field of casting processing, in particular to an upper flange riser-free pouring system for a compressor and a production process of an upper flange.

Background

With the continuous progress of science and technology, the living standard of people is increasingly improved, the environmental awareness of people is also improved, and the living quality is also required to be higher. Higher requirements are also put forward for household appliances closely related to each family. Taking an air conditioner as an example, people pay more attention to energy conservation, environmental protection and mute comfort of the air conditioner, so that higher requirements are put forward for various air conditioner manufacturers, and higher requirements are put forward for the performance of a compressor of a core part of the air conditioner. I regard as one of the outstanding air condition compressor core spare part supply producers of industry product coverage area widest, product specification model is the most complete, equipment ability is most outstanding, and the corresponding research and development degree that has also strengthened the compressor foundry goods promotes product quality to satisfy the requirement of customer to the higher quality of product.

The current labor cost is continuously increased, the environmental protection requirement of the industry is higher and higher, the staff is more and more paid and profitable and the environmental protection investment is more and more, the production cost is higher and more, and the profit is lower and more. In addition, the market competition is more and more intense due to the addition of some new manufacturers, and the companies can survive in the existing severe market environment only by continuously reducing cost, improving efficiency, developing innovation, improving product quality and improving market share.

The bearing is a core part of the compressor, and in the high-speed running process of the compressor, due to the combined action of the magnetic attraction force generated between the stator and the rotor of the motor and the eccentric force generated by the eccentric part of the crankshaft, on one hand, the crankshaft and the handle part of the bearing are radially deformed, so that the vibration and the noise of the compressor are increased; on the other hand, the shanks of the upper and lower bearing shafts are tightly attached to the periphery of the crankshaft to form friction pairs, the friction pairs are partially in surface contact, the surface pressure is extremely high, the contact surfaces are easily subjected to large abrasion and even sintering, and the reliability of the long-term operation of the compressor is affected, so that the bearing is required to have high mechanical properties. The handle part of the central shaft of the bearing is the thickest part of the casting and is the hot junction of the casting, the traditional production process adopts a riser feeding production process, the process yield is low, the wall thickness of the spoke position of the bearing is thin, a feeding channel is not smooth, the feeding effect is not ideal, and the hot junction of the casting moves outwards under the interaction of a temperature field, so that the phenomenon of slight non-tightness after the inner hole of part of the casting is processed is caused, and the requirement of the existing compressor on the high performance of the bearing is not met.

The invention discloses a nodular cast iron bearing for a compressor, which is disclosed in patent ZL201510406233.6 in 2015 by the inventor of Jingtong machinery limited in Zhaoqing, and the nodular cast iron bearing comprises a flange and a handle positioned in the middle of the flange, wherein the lower end of the handle is provided with a half opening which takes a central axis of the bearing as an axis and is upward from the end surface of the flange, the height of the half opening is more than 1.5 times of the height of the flange and less than the total height of the nodular cast iron bearing for the compressor, and the aperture size of the half opening is 20-90% of the diameter of the handle. According to the design principle of the nodular cast iron bearing for the compressor, the diameter of a thermal pitch circle of a flange plate of a nodular cast iron bearing casting for the compressor, which is close to the end face, is smaller than that of a thermal pitch circle of the center part of the handle part by designing a semi-open pore structure, so that the thermal pitch circle of the center part on the handle part becomes the final solidification position of the nodular cast iron bearing casting for the compressor, the defects of shrinkage cavity and shrinkage porosity are controlled to the position of the thermal pitch circle of the center part on the handle part and are distributed and concentrated, and the subsequent shrinkage cavity and shrinkage porosity positions are removed in a drilling mode.

The solution is to move the thermal pitch circle to the upper center part of the handle by providing half-holes in the flange.

This solution is an effective solution; however, the product produced by the method is a flange, a plurality of thin spokes are arranged on the flange, the traditional casting process of riser feeding is adopted, the feeding channel is too long, the feeding effect is not ideal, and the interaction of a temperature field causes the hot nodes of the casting to move outwards, so that the phenomenon of slight non-densification is caused after the inner holes of partial castings are machined, and the requirement of customers on high quality and high performance of the product cannot be met; the corresponding technical problems cannot be solved by adopting the means.

Meanwhile, the gray cast iron upper flange needs to be prepared at this time, and the ZL201510406233.6 nodular cast iron flange needs to be prepared, so that the gray cast iron upper flange cannot be prepared by adopting the scheme means in the formula.

Therefore, the technical problem to be solved by the scheme is as follows: how to control the position of the thermal pitch circle to reach the central position on the handle part so as to improve the product quality.

Disclosure of Invention

The invention aims to provide an upper flange non-riser pouring system for a compressor, which can control the position of a thermal pitch circle, stabilize molten iron filling and avoid turbulence, and also provides a production process, wherein the formula is improved, so that the product quality is comprehensively improved.

In order to achieve the purpose, the invention provides the following technical scheme: a riser-free pouring system for an upper flange of a compressor comprises a sand casting mold, wherein a plurality of cavities matched with the upper flange in shape are arranged in the sand casting mold, a pouring cup, a cross gate, a vertical gate and an inner gate which are sequentially connected are arranged in the sand casting mold, and the inner gate is communicated with the cavities; the inner gate is of a wedge-shaped thin sheet structure; the cavity is connected with an exhaust strip; the vertical pouring gate is provided with a pressure reduction groove, and the cavity is internally provided with a plurality of spoke grooves corresponding to spokes of the upper flange; the at least one spoke groove is opposite to the inner sprue; the pressure reduction groove is positioned between two rows of cavities which are arranged up and down.

In the upper flange riser-free pouring system for the compressor, the tail end of the horizontal pouring gate is of a wedge-shaped structure.

In the above-described upper flange feeder-less gating system for a compressor, the horizontal runner and the vertical runner are connected by a dovetail joint.

In the upper flange non-riser pouring system for the compressor, the ratio of the cross section area of the horizontal pouring gate, the cross section area of the dovetail joint part, the cross section area of the vertical pouring gate and the cross section area of the maximum cross section area of the ingate is 1:0.8:1: 1.05.

In the upper flange non-riser pouring system for the compressor, the ratio of the cross section area of the horizontal pouring gate, the cross section area of the dovetail joint part, the cross section area of the vertical pouring gate and the cross section area of the maximum cross section area of the ingate is 1:0.8:1: 1.05.

Meanwhile, the invention also discloses a production process of the upper flange for the compressor, which adopts any one of the pouring systems for pouring; the components of the poured molten iron are as follows:

c: 3.35-3.45%, Si: 2.30-2.40%, Mn: 0.65-0.80%, P < 0.06%, S: 0.06-0.10%, trace Sb or Sn, and the balance of iron.

In the production process of the upper flange for the compressor, the smelting temperature of the poured molten iron is 1480-1520 ℃; standing for 5-10min after smelting the molten iron; the temperature of molten iron is 1400-1420 ℃ during pouring.

In the production process of the upper flange for the compressor, the temperature of molten iron is 1400-1420 ℃ during pouring; the quantity of molten iron discharged from each ladle is controlled to be 670 plus or minus 10kg, and the pouring time of each ladle is less than or equal to 8 minutes.

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

1. the inner gate is a wedge-shaped sheet structure, so that molten iron stably flows into a casting cavity, a slag (sand) blocking effect is achieved, the pressure reduction groove and the spoke groove are combined, the molten iron injection speed can be reduced through the pressure reduction groove, the molten iron inflow stability can be improved, and the spoke groove and the inner gate are right opposite to each other, so that the mold filling stability can be improved.

2. The inner pouring gate is of a wedge-shaped sheet structure, and is firstly solidified in a solidification stage, so that the mutual influence between the vertical pouring gate and the cavity can be avoided.

3. The casting process of the traditional riser feeding is cancelled, and the feeding effect is improved through the comprehensive improvement on a casting system.

In combination with the above 1-3, the casting thermal node can reach the middle upper position of the handle and can be removed after the hole is opened. The product percent of pass is improved.

Meanwhile, the tail end of the cross gate is of a wedge-shaped structure, so that the filling stability can be improved, and the backflow of molten iron is avoided.

The dovetail joint has the function of blocking slag (sand).

In addition, the process of the invention changes the formula, improves the CE value, reduces the liquidus temperature, improves the expansion effect generated by graphite precipitation in the casting solidification process, enables the contraction and expansion to be mutually offset, and finally realizes that the casting with high quality and compact central handle can be produced without a riser.

In addition, 0.02-0.035% of Sb or Sn is added to refine graphite, pearlite content is increased, and strength and hardness of the product are improved.

Drawings

FIG. 1 is a structural view of embodiment 1 of the present invention;

fig. 2 is a sectional view of a part C of embodiment 1 of the present invention in a vertical plane;

FIG. 3 is a top view of the upper flange of examples 1 and 2 of the present invention;

FIG. 4 is a cross-sectional view of an upper flange of examples 1 and 2 of the present invention;

fig. 5 is a sectional view of an in-gate of example 1 of the present invention;

FIG. 6 is a cross-sectional view of an upper flange of comparative example 1 of the present invention;

FIG. 7 is a schematic diagram of the construction of the gating system of comparative example 1 of the present invention.

Detailed Description

The technical solutions in the embodiments of the present invention will be clearly and completely described below with reference to the drawings in the embodiments of the present invention, and it is obvious that the described embodiments are only a part of the embodiments of the present invention, and not all of the embodiments. All other embodiments, which can be derived by a person skilled in the art from the embodiments given herein without making any creative effort, shall fall within the protection scope of the present invention.