CN216758063U

CN216758063U - Stepped pouring system

Info

Publication number: CN216758063U
Application number: CN202122824243.5U
Authority: CN
Inventors: 孙袁; 倪炳华
Original assignee: TONGXIANG HEDE MACHINERY CO Ltd
Current assignee: TONGXIANG HEDE MACHINERY CO Ltd
Priority date: 2021-11-17
Filing date: 2021-11-17
Publication date: 2022-06-17
Anticipated expiration: 2031-11-17

Abstract

The utility model discloses a stepped pouring system which comprises a pouring gate, a connecting gate, a cavity and a riser, wherein the pouring gate comprises a sprue and a bent pipe, the bent pipe is connected to the bottom end of the sprue, the connecting gate is communicated with the cavity, and the riser is communicated with the top of the cavity. When the method pours the molten iron by stages and layers, the defects of slag holes, shrinkage porosity, air holes and the like in the casting can be reduced by early-stage bottom pouring and later-stage top pouring, so that the casting achieves a compact effect, and the casting quality and the process yield are improved.

Description

Stepped pouring system

Technical Field

The utility model relates to the technical field of casting, in particular to a stepped gating system.

Background

The existing pouring system generally adopts bottom pouring or top pouring, namely molten iron is poured into a sand mold cavity from the bottom or the top of the sand mold cavity and fills the cavity, but the two pouring systems have the defects, mainly because when the cavity is finally filled with the molten iron, the molten iron poured in earlier stage is cooled for a long time, and then is shrunk, the flowability is deteriorated, the volume is also reduced, so that the problems of slag holes, shrinkage porosity, air holes and the like are caused, and the molten iron poured in later stage is difficult to reach the position occupied by the molten iron in earlier stage, so that the defects are difficult to be compensated. For example, when the bottom pouring method is adopted for casting, the liquid level of the molten iron gradually rises in the cavity, the temperature of the molten iron on the upper part is lower, the liquidity is poorer, the molten iron injected later hardly penetrates through the lower-temperature molten iron on the upper part to completely cover the top of the molten iron injected in the front when the later pouring is finished, and once a cavity is generated by the cold shrinkage of the top injected in the front, the cavity cannot be compensated by the hot molten iron with better liquidity injected later, so that the quality of a final casting cannot be guaranteed. The utility model patent with publication number CN113333681A discloses an assembled tandem type multi-box gating system; the system comprises a U-shaped pouring channel and a transverse pouring channel; the U-shaped pouring gate consists of a bottom pouring gate and longitudinal pouring gates arranged at two ends of the bottom pouring gate; the ports of the two longitudinal pouring channels respectively form an outer pouring gate and a riser, and an inclined pouring channel which is obliquely and upwardly distributed from the longitudinal pouring channel where the outer pouring gate is located to the longitudinal pouring channel where the riser is located is arranged between the two longitudinal pouring channels; a plurality of transverse pouring channels are longitudinally distributed at intervals and are communicated with the outer sides of the longitudinal pouring channels where the risers are located; the bottom of the transverse pouring gate is provided with a plurality of inner pouring gates which are connected with a casting cavity of the sand mold; the utility model effectively solves the problems of spheroidization recession, molten iron waste, inconsistent casting quality and the like of the traditional single-box pouring system and the traditional multi-box pouring system. However, the utility model essentially adopts a one-way pouring mode to finish the casting molding, and cannot effectively solve a series of problems caused by cold contraction of the molten iron entering the cavity earlier.

SUMMERY OF THE UTILITY MODEL

The utility model provides a stepped pouring system which effectively enhances the stability of upper molten iron, obtains better feeding effect and ensures that a casting is qualified, in order to overcome the defects that the casting quality is influenced by the problems of slag holes, shrinkage porosity, air holes and the like easily occurring during the operation of the existing pouring system.

The technical scheme of the utility model is as follows: the utility model provides a cascaded gating system, includes that the filling waters, connects and waters, die cavity and rising head, and the filling is watered including sprue and return bend, and the return bend is connected in the sprue bottom, connects and waters and die cavity intercommunication, rising head and die cavity top intercommunication, and characterized by connects to water including the end watering and the runner of top, the end watering and the runner of top all with the filling waters the intercommunication, the filling is watered and is the U-shaped, and the sprue includes inboard sprue and outside sprue, and the end is watered and is connected bottom and top including the inboard sprue respectively with the runner of top, through a transition cross gate intercommunication between two sprues, and the intercommunication mouth position of transition cross gate and sprue is in between end watering and the runner of top. Molten iron is filled from the port of the outer side sprue, the transition cross gate is used for changing a pouring path at the later molding stage of a casting, and the cavity and the filling gate form a communicating vessel. The later-stage injected molten iron covers the top of the earlier-stage injected molten iron, and heats the earlier-stage injected and cooled molten iron again, so that the upper layer of the earlier-stage injected molten iron has no slag hole floating upwards, and air which has no time to escape has more chances to transfer upwards due to the temperature rise and the mobility enhancement of the molten iron, so that the molten iron is easier to surface and easier to find and timely process and clean. And the shrinkage porosity generated by molten iron injected in the early stage and cooled can be effectively compensated by direct filling of molten iron injected in the later stage and remelting rheology of the molten iron. When pouring, excessive molten iron is poured, the excessive molten iron is stored in the riser, most of the accumulated shrinkage generated after the casting is cooled is concentrated in the riser, the riser is cut off after the casting is formed, and the defects of slag holes, shrinkage porosity, air holes and the like of the casting are reduced as much as possible, so that the casting quality is improved.

Preferably, ingates are arranged between the bottom pouring channel and the cavity and between the top pouring channel and the cavity. The inner pouring channel forms good transition among the bottom pouring channel, the top pouring channel and the cavity, and reduces mutual interference among the bottom pouring channel and the cavity and between the top pouring channel and the cavity.

Preferably, the bottom pouring channel comprises a drainage channel and an annular channel, the front end of the drainage channel is communicated with the filling pouring channel, the rear end of the drainage channel is communicated with the annular channel, and ingates between the bottom pouring channel and the cavity are uniformly distributed on the annular channel. This structure is convenient for molten iron evenly distributed, pours into the die cavity into simultaneously from a plurality of directions into, more does benefit to the homogeneity of ensureing the foundry goods.

Preferably, the top pouring gate is in a sector ring shape, and inner pouring gates between the top pouring gate and the cavity are uniformly distributed on the inner periphery of the top pouring gate in a radial shape. This structure is convenient for molten iron evenly distributed, pours into the die cavity into simultaneously from a plurality of directions into, more does benefit to the homogeneity of ensureing the foundry goods.

Preferably, the bottom runner and the top runner are of equal cross-sectional area. Therefore, approximately equal pouring flow can be provided in the processes of early bottom pouring and later top pouring, and the homogeneity of the casting molded by stage pouring is favorably ensured.

Preferably, the transition runners are of equal cross-sectional area to the sprue. Therefore, the flow is approximately stable during the staged pouring, and the homogeneity of the cast molded by staged pouring is ensured.

Preferably, the filling runner is made of a ceramic tube. The ceramic tube is high temperature resistant and is an independent component, which can be conveniently arranged.

The utility model has the beneficial effects that:

improve the casting quality and improve the process qualification rate. When the method is used for pouring molten iron in stages and layers, the defects of slag holes, shrinkage porosity, air holes and the like in the molten iron can be reduced gradually by early-stage bottom pouring and later-stage top pouring, and the casting quality is improved.

Drawings

FIG. 1 is a schematic structural diagram of the present invention;

FIG. 2 is a schematic longitudinal sectional view of the present invention;

FIG. 3 is a schematic view of another embodiment of the present invention.

In the figure, 1-sprue, 2-elbow, 3-bottom sprue, 4-top sprue, 5-transition runner, 6-chill, 7-ingate, 8-riser, 9-casting and 10-cavity.

Detailed Description

The utility model is further illustrated by the following specific embodiments in conjunction with the accompanying drawings.

Example 1:

as shown in fig. 1 to 3, a stepped gating system is based on a casting mold for casting a piston support of an injection molding machine. The stepped pouring system comprises a filling pouring gate, a connecting pouring gate, a cavity 10 and a riser 8, wherein the connecting pouring gate and the cavity 10 are directly formed in a sand mold of a casting mold, and the filling pouring gate and the riser 8 are arranged on the sand mold of the casting mold. The filling runner is made of a ceramic tube and comprises a sprue 1 and an elbow 2, wherein the elbow 2 is connected to the bottom end of the sprue 1, and the connecting runner is communicated with the cavity. The riser 8 is communicated with the top of the cavity, the connecting runner comprises a bottom runner 3 and a top runner 4, and the bottom runner 3 and the top runner 4 are communicated with the filling runner. The bottom runner 3 and the top runner 4 have the same cross-sectional area. The sprue is U-shaped, the sprue 1 comprises an inner sprue and an outer sprue, a pouring cup is arranged at the top end of the outer sprue, the bottom sprue 3 and the top sprue 4 are respectively connected to the bottom and the top of the inner sprue, a transition cross runner 5 is further connected between the two sprues 1, the transition cross runner 5 is communicated with the two sprues 1, the communication port of the transition cross runner 5 and the sprue 1 is positioned between the bottom sprue 3 and the top sprue 4, the transition cross runner 5 is obliquely arranged, and the communication port of the transition cross runner 5 and the outer sprue is higher than the communication port of the transition cross runner 5 and the inner sprue. The transition runner 5 is of equal cross-sectional area to the sprue 1. The cross-sectional area ratio of the sprue 1 to the bottom runner 3 is 1: 1.5. And ingates 7 are arranged between the bottom pouring channel 3 and the cavity and between the top pouring channel 4 and the cavity. The bottom pouring channel 3 comprises a drainage channel and an annular channel, the front end of the drainage channel is communicated with the filling pouring channel, the rear end of the drainage channel is communicated with the annular channel, and ingates 7 between the bottom pouring channel 3 and the cavity are uniformly distributed on the annular channel. The top pouring channel 4 is in a sector ring shape, and inner pouring channels 7 between the top pouring channel 4 and the cavity are uniformly distributed on the inner periphery of the top pouring channel 4 in a radial shape. The cross-sectional area ratio of the bottom runner 3 to the corresponding ingate 7 is 1: 1.2. Similarly, the cross-sectional area ratio of the top runner 4 to the corresponding ingate 7 is also 1: 1.2. And a chill 6 is arranged around the outside of the cavity at the joint of the inner pouring channel 7.

The working method of the stepped gating system comprises the following steps:

step one, molten iron enters the filling pouring gate through a pouring cup, enters a cavity through an inner side sprue, a bottom pouring channel 3 and an inner pouring gate 7 on the bottom pouring channel 3, and is filled with molten iron from the bottom of the cavity;

secondly, under the chilling action of a chilling block 6 at the bottom of the cavity, the lower layer molten iron in the cavity is firstly solidified;

step three, when molten iron enters the middle upper layer of the inner side sprue and finally reaches the position of the transition cross runner 5, the molten iron mainly continuously fills the cavity through the transition cross runner 5, the top runner 4 and the ingate 7 on the top runner 4, namely the molten iron is filled from the top of the cavity, and the overflowing molten iron enters a riser 8;

feeding the cold-shrunk molten iron on the lower layer of the cavity by the hot molten iron on the upper layer, gradually solidifying the molten iron filled from the top of the cavity from bottom to top under the chilling action of the cold iron 6 on the top of the cavity, and finally solidifying a riser 8, wherein the final shrinkage defect is introduced into the riser 8;

and step five, forming the casting 9 and cutting off the riser 8.

Example 2:

the cross-sectional area ratio of the sprue 1 to the bottom runner 3 is 1: 2. The cross-sectional area ratio of the bottom pouring channel 3 to the corresponding inner pouring channel 7 is 1:1.5, and the cross-sectional area ratio of the top pouring channel 4 to the corresponding inner pouring channel 7 is also 1: 1.5. The rest is the same as example 1.

Example 3:

the cross-sectional area ratio of the sprue 1 to the bottom runner 3 is 1: 1.8. The cross-sectional area ratio of the bottom runner 3 to the corresponding ingate 7 is 1: 1.3. The cross-sectional area ratio of the top runner 4 to the corresponding ingate 7 is also 1: 1.3. The rest is the same as example 1.

Claims

1. A stepped pouring system comprises a filling pouring gate, a connecting pouring gate, a cavity and a riser (8), wherein the filling pouring gate comprises a sprue (1) and a bent pipe (2), the bent pipe (2) is connected with the bottom end of the sprue (1), the connecting pouring gate is communicated with the cavity, the riser (8) is communicated with the top of the cavity, it is characterized in that the connecting pouring gate comprises a bottom pouring gate (3) and a top pouring gate (4), the bottom pouring gate (3) and the top pouring gate (4) are both communicated with the filling pouring gate, the sprue is U-shaped, the sprue (1) comprises an inner sprue and an outer sprue, the bottom sprue (3) and the top sprue (4) are respectively connected to the bottom and the top of the inner sprue, the two sprues (1) are communicated through a transition cross gate (5), and the communication port of the transition cross gate (5) and the sprue (1) is positioned between the bottom sprue (3) and the top sprue (4).

2. The stepped gating system of claim 1, wherein an ingate (7) is provided between the bottom runner (3) and the cavity and between the top runner (4) and the cavity.

3. The stepped gating system according to claim 2, characterized in that the bottom runner (3) comprises a drainage channel and an annular channel, the front end of the drainage channel is communicated with the filling runner, the rear end of the drainage channel is communicated with the annular channel, and ingates (7) between the bottom runner (3) and the cavity are uniformly distributed on the annular channel.

4. The stepped gating system of claim 2, wherein the top gate (4) is in the shape of a sector ring, and the ingates (7) between the top gate (4) and the cavity are radially and uniformly distributed on the inner periphery of the top gate (4).

5. Stepped gating system according to claim 1, characterized in that the bottom runner (3) and the top runner (4) have equal cross-sectional areas.

6. A stepped gating system according to claim 1, characterized in that the transition runner (5) and the sprue (1) are of equal cross-sectional area.

7. The stepped gating system of any one of claims 1 to 6, wherein said fill sprue is formed from a ceramic tube.