CN209736560U

CN209736560U - Casting die good in forming

Info

Publication number: CN209736560U
Application number: CN201920502655.7U
Authority: CN
Inventors: 宁林祥
Original assignee: Zhejiang Oyeda Machinery Manufacturing Co Ltd
Current assignee: Zhejiang Oyeda Machinery Manufacturing Co Ltd
Priority date: 2019-04-15
Filing date: 2019-04-15
Publication date: 2019-12-06
Anticipated expiration: 2029-04-15

Abstract

The utility model discloses a good casting mould of shaping, include last mould (1) and lower mould (2) by the preparation of furan resin self-hardening sand, go up mould (1) and connect lower mould (2) through double-screw bolt (11), the upper surface of lower mould (2) is equipped with the die cavity with impeller shape matched with, it has a plurality of chills (21) to inlay in the die cavity, the position of chills (21) corresponds to the distal end of blade (31), be equipped with sprue (13) in last mould (1), the upper end of sprue (13) is located the upper surface of last mould (1), the lower extreme of sprue (13) extends to in lower mould (2), the lower extreme of sprue (13) is connected with a plurality of circumferentially distributed subchannel (14), the tip of subchannel (14) is equipped with runner (15), the position of runner (15) corresponds to the inner wall of axle sleeve (32); the utility model has the advantages of high casting qualification rate, low processing cost, low material cost, high energy conversion efficiency and high manufacturing speed.

Description

Casting die good in forming

Technical Field

The utility model belongs to cast iron impeller's casting mould field especially relates to a good casting mould of shaping.

Background

Large-scale cast iron impeller (for short, impeller), like the hydraulic turbine impeller, including carousel and a plurality of blade, blade circumference distributes on the carousel, and the requirement for blade size precision is higher, and the centre of carousel is equipped with the axle sleeve with main shaft complex, and the runner position of casting mould corresponds to the carousel. During pouring, the rotating disc is filled with molten iron, the shaft sleeve is filled with molten iron, and finally the blades are filled with molten iron. In the casting process, because the blade is long and thin, air in a cavity position corresponding to the blade is difficult to evacuate when molten iron is poured, the molten iron is not completely filled, the blade is incompletely formed, the casting qualification rate of the impeller is low, after the pouring is finished, the molten iron at the blade is firstly solidified, the solidification at a specific certain position of the blade is uncontrollable, the molten iron is usually solidified from the far end of the blade and then gradually solidified towards the root part of the blade connected with the rotating disc, which is the most ideal state, however, the volume is reduced in the process of solidifying the blade, the outline dimension of the blade is reduced, so the dimension of the cavity in which the blade is positioned needs to be enlarged, the dimension of the blade obtained by casting exceeds the actual required dimension of the blade, then the edge of the blade is precisely ground to obtain the actual required dimension of the blade, the blade is complicated to form, the processing cost of the impeller is improved, and sometimes the root part of the blade connected with the rotating, the iron block that the solidification formed separates blade distal end and runner, the blade condensation shrink back, the molten iron can not in time supply to the blade distal end, the edge that leads to the blade distal end appears the breach, the edge of blade distal end also can appear loosely, the foundry goods is unqualified, appear for avoiding this kind of condition, the blade that needs to thicken usually, remote end from the blade thickens gradually to the root of blade, blade thickness seriously exceeds the actual required thickness of blade, directly lead to the impeller weight to increase, not only make material cost increase, and make the required power of drive impeller increase, the energy conversion efficiency of impeller reduces. After the impeller is cast, large stress exists and needs to be eliminated, and the impeller is large in size and is not suitable for being placed in a furnace for tempering and eliminating the stress, so that the stress is usually eliminated by means of natural aging, at least 6 months are needed, and the manufacturing speed of the impeller is low. Therefore, the impeller cast by the existing casting mould has the defects of low casting yield, high processing cost and long manufacturing time, or has the defects of low casting yield, high material cost, low energy conversion efficiency and slow manufacturing speed.

SUMMERY OF THE UTILITY MODEL

An object of the utility model is to provide a good casting mould of shaping. The utility model has the advantages of high casting qualification rate, low processing cost, low material cost, high energy conversion efficiency and high manufacturing speed.

The technical scheme of the utility model: the utility model provides a good casting mould of shaping, include last mould and lower mould by furan resin self-hardening sand preparation, it passes through the double-screw bolt connection lower mould to go up the mould, the upper surface of lower mould is equipped with the die cavity with impeller shape matched with, it has a plurality of chills to inlay in the die cavity, the position of chiller is corresponding to the distal end of blade, be equipped with the sprue in going up the mould, the upper end of sprue is located the upper surface of mould, the lower extreme of sprue extends to in the lower mould, the lower extreme of sprue is connected with the subchannel that a plurality of circumference distribute, the tip of subchannel is equipped with the runner, the position of runner corresponds the inner wall of axle sleeve.

In the casting mould with good forming, the cavity comprises a step hole matched with the shape of the rotary table, the depth of the step hole is larger than the thickness of the rotary table, a lower pressing plate is embedded at the bottom of the upper mould, the lower part of the lower pressing plate is embedded into the step hole, an upper pressing plate is arranged above the upper mould and is connected with the lower pressing plate through a plurality of guide pillars, and guide holes matched with the guide pillars are formed in the upper mould.

In the well-formed casting mold, the upper pressure plate is fixed with the vibration motor.

In the well-formed casting die, the stud penetrates through the upper die and then is connected with the lower die, and the lower end of the stud is provided with the nut which is embedded in the lower die.

In the well-formed casting mold, the number of the branch runners is four, and the branch runners are distributed in a cross shape.

In the well-formed casting mold, a framework surrounding the cavity is arranged in the lower mold, and the distance between the cavity and the framework is 1-3 cm.

Compared with the prior art, the utility model discloses a mould and lower mould are gone up in furan resin self-hardening sand preparation to make and go up mould and lower mould and all have good gas permeability and rigidity, after the die cavity is poured into to the molten iron, the air in the die cavity that the blade corresponds can pass the lower mould and discharge, and the molten iron can be better be full of the die cavity position that the blade corresponds, and the blade shaping is good complete, and the casting qualification rate of impeller is high.

Through setting up the chilling block and accelerating the cooling rate of blade distal end, guarantee that the distal end of blade is the first to rise and solidify, blade distal end and runner remain unblocked throughout, the die cavity vacancy that the blade distal end solidification brought can be supplemented by the molten iron in the runner, guarantee that the die cavity position that the blade distal end corresponds can be full of by the molten iron all the time, the blade shaping is complete, need not thicken the blade, impeller weight has been reduced, material cost has been reduced promptly, also make the required power of drive impeller reduce, the energy conversion efficiency of impeller improves.

When the molten iron pouring is completed and begins to solidify gradually, give holding down plate pressure through the top board, the foundry goods is compaction under the pressure effect, avoid the inside looseness that appears of foundry goods, the die cavity position that the blade corresponds simultaneously is complete filling all the time under the pressure effect, can not produce the cavity because of the blade cooling, size after the blade shaping is accurate, only need be exactly the blade actual need size with the die cavity position size that the blade corresponds, the blade after the shaping need not carry out the precision grinding, the processing cost of impeller has been reduced.

After molten iron is completely cooled in the cavity, a certain shaking is applied to the casting through the vibrating motor, the casting is firstly separated from the cavity wall, the casting is convenient to take out of the mold, secondly, a part of casting stress is eliminated by the casting under the action of the vibrating motor, the subsequent old natural aging time of the casting is reduced to about four months, and the impeller manufacturing time is reduced.

Therefore, the utility model has the advantages of the casting qualification rate is high, the processing cost is low, material cost is low, energy conversion efficiency is high and manufacturing speed is very fast.

Drawings

Fig. 1 is a front view of the present invention.

fig. 2 is a top view of the runner.

Fig. 3 is a schematic structural view of the skeleton.

Fig. 4 is a front view of the impeller.

Fig. 5 is a plan view of the impeller.

The labels in the figures are: 1-upper die, 2-lower die, 3-vibrating motor, 11-stud, 13-main runner, 14-branch runner, 15-sprue, 16-lower pressing plate, 17-upper pressing plate, 18-guide pillar, 19-nut, 21-chill, 22-framework, 31-blade, 32-shaft sleeve and 33-rotary table.

Detailed Description

The following description is made with reference to the accompanying drawings and examples, but not to be construed as limiting the invention.

examples are given. The utility model provides a good casting mould of shaping, as shown in fig. 1, include last mould 1 and lower mould 2 by the preparation of furan resin self-hardening sand, it all is sticky from the hard sand of furan resin to form to go up mould 1 and lower mould 2, it connects lower mould 2 through double-screw bolt 11 to go up mould 1, the upper surface of lower mould 2 is equipped with the die cavity with impeller shape matched with, it has a plurality of chills 21 to inlay in the die cavity, the position of chills 21 corresponds to the distal end of blade 31, upward be equipped with sprue 13 in the mould 1, the upper end of sprue 13 is located the upper surface of last mould 1, the lower extreme of sprue 13 extends to in the lower mould 2, the lower extreme of sprue 13 is connected with a plurality of circumferentially distributed's subchannel 14, the tip of subchannel 14 is equipped with runner 15, the position of runner 15.

The die cavity comprises a step hole matched with the shape of the rotary table 33, the depth of the step hole is larger than the thickness of the rotary table 33, a lower pressing plate 16 is embedded at the bottom of the upper die 1, the lower part of the lower pressing plate 16 is embedded in the step hole, an upper pressing plate 17 is arranged above the upper die 1, the upper pressing plate 17 is connected with the lower pressing plate 16 through a plurality of guide pillars 18, and guide holes matched with the guide pillars 18 are formed in the upper die 1.

The upper pressure plate 17 is fixed with the vibration motor 3, and the exciting force of the vibration motor 3 is 180 kilonewtons.

The stud 11 penetrates through the upper die 1 and then is connected with the lower die 2, and the lower end of the stud 11 is provided with a nut 19 which is pre-buried in the lower die 2.

The number of the branch runners 14 is four, and the branch runners are distributed in a cross shape.

The lower die 2 is internally provided with a framework 22 surrounding the cavity, the distance between the cavity and the framework 22 is 1-3cm, the framework 22 is made of carbon steel pore plates, is cylindrical and has a wall thickness of more than 4mm, and the framework 22 is used for enhancing the strength of the lower die 2 and preventing the lower die 2 from being cracked under pressure.

Casting: a. according to the parts by weight, 100 parts of QT450-10 type cast iron is smelted by adopting a 2T medium-frequency induction furnace, 1.2 parts of graphite and 0.6 part of inoculant are added, the mixture is uniformly stirred to obtain molten iron, the temperature of the molten iron is 1380 ℃,

b. Molten iron sequentially passes through the main runner 13, the sub-runner 14 and the pouring gate 15 to reach a cavity, after cooling for 1-1.5 hours or more than half of the molten iron in the cavity is solidified, a press is used for applying certain pressure on the upper pressure plate 17 until the molten iron is completely cooled, the pressure is correspondingly changed according to the size and the shape of an impeller, the larger the pressure applied by the impeller is, the specific pressure value is based on the fact that the size deviation of the obtained blade 31 and the size deviation of the cavity corresponding to the blade 31 can not exceed 0.1% (the deviation does not exceed 0.1%, namely the position size of the cavity corresponding to the blade is regarded as the size of the blade), the pressure value can be obtained through a plurality of tests,

c. Starting the vibration motor 3, stopping after working for 3-5 hours,

d. And loosening the stud 11, taking out the casting and cleaning to obtain a finished product.

Claims

1. a casting mould that shaping is good, its characterized in that: including last mould (1) and lower mould (2) by furan resin self-hardening sand preparation, go up mould (1) and connect lower mould (2) through double-screw bolt (11), the upper surface of lower mould (2) is equipped with the die cavity with impeller shape matched with, it has a plurality of chills (21) to inlay in the die cavity, the position of chills (21) corresponds to the distal end of blade (31), upward be equipped with sprue (13) in mould (1), the upper end of sprue (13) is located the upper surface of last mould (1), the lower extreme of sprue (13) extends to in lower mould (2), the lower extreme of sprue (13) is connected with subchannel (14) of a plurality of circumference distributions, the tip of subchannel (14) is equipped with runner (15), the position of runner (15) corresponds the inner wall of axle sleeve (32).

2. The well-formed casting mold of claim 1, wherein: the die cavity comprises a step hole matched with the shape of the rotary table (33), the depth of the step hole is larger than the thickness of the rotary table (33), a lower pressing plate (16) is embedded at the bottom of the upper die (1), the lower part of the lower pressing plate (16) is embedded into the step hole, an upper pressing plate (17) is arranged above the upper die (1), the upper pressing plate (17) is connected with the lower pressing plate (16) through a plurality of guide pillars (18), and guide holes matched with the guide pillars (18) are formed in the upper die (1).

3. The well-formed casting mold of claim 2, wherein: and a vibration motor (3) is fixed on the upper pressure plate (17).

4. The well-formed casting mold of claim 1, wherein: the stud (11) penetrates through the upper die (1) and then is connected with the lower die (2), and a nut (19) which is embedded in the lower die (2) is arranged at the lower end of the stud (11).

5. The well-formed casting mold of claim 1, wherein: the number of the branch runners (14) is four, and the branch runners are distributed in a cross shape.

6. The well-formed casting mold of claim 1, wherein: a framework (22) surrounding the cavity is arranged in the lower die (2), and the distance between the cavity and the framework (22) is 1-3 cm.