CN209998302U

CN209998302U - large diesel engine piston casting sand mold structure

Info

Publication number: CN209998302U
Application number: CN201920726400.9U
Authority: CN
Inventors: 张金荣; 陆文兴
Original assignee: Guangdong Hong Te Precision Technology Zhaoqing Co Ltd
Current assignee: Guangdong Hong Te Precision Technology Zhaoqing Co Ltd
Priority date: 2019-05-20
Filing date: 2019-05-20
Publication date: 2020-01-31
Anticipated expiration: 2029-05-20

Abstract

The utility model discloses an large-scale diesel engine piston casting sand mould structure, bottom circular chiller is arranged in the bottom of sand box, semi-annular chiller makes up into rings, arranges around the lower part of diesel engine piston foundry goods position, and forms slit formula lower horizontal runner at the butt joint position and becomes the molten metal inflow mouth, a plurality of pinhole annular chills symmetric distribution, installs in the position corresponding with diesel engine piston pinhole, and the upper horizontal runner is linked together with vertical runner, and is linked together with diesel engine piston casting sand mould upper portion space, and vertical runner, upper horizontal runner and slit formula lower horizontal runner constitute ladder pouring runner, and diesel engine piston casting sand mould is provided with a plurality of air risers.

Description

large diesel engine piston casting sand mold structure

Technical Field

The utility model relates to an kinds of casting sand mould structures specifically indicate kinds of large-scale diesel engine piston casting sand mould structures.

Background

In the casting production process of ductile iron pieces, although the precipitation of graphite in the casting solidification process can bring volume expansion to make up for volume contraction caused by liquid-solid transformation, large diesel engine piston castings have complex structures, and the defects caused by casting solidification contraction are difficult to eliminate only by means of graphite expansion, so that the rejection rate of products is high, the quality is difficult to guarantee, and the production efficiency and the cost are directly influenced for production enterprises.

SUMMERY OF THE UTILITY MODEL

The utility model aims to overcome prior art's weak point, design large-scale diesel engine piston casting sand mould structures that can eliminate the casting defect of solidifying.

The utility model aims at realizing through the following technical scheme:

A large diesel engine piston casting sand mold structure is characterized by comprising a sand box, a slit type lower transverse pouring gate, a vertical pouring gate, an upper pouring gate, a plurality of air risers, a pin hole annular chiller, semi-annular chiller and a bottom circular chiller, wherein the bottom circular chiller is arranged at the bottom of the sand box, the semi-annular chiller is combined into rings and is arranged around the lower part of a diesel engine piston casting, the slit type lower transverse pouring gate is formed at a butt joint position to serve as a molten metal inflow port, the plurality of pin hole annular chills are symmetrically distributed and arranged at positions corresponding to pin holes of a diesel engine piston, the upper pouring gate is communicated with the vertical pouring gate and is communicated with the upper space of the diesel engine piston casting sand mold, the vertical pouring gate, the upper pouring gate and the slit type lower transverse pouring gate form a step pouring flow channel, and the diesel engine piston casting sand mold is provided.

Preferably, the left exhaust riser is located at the upper left part of the diesel engine piston casting sand mold, the right exhaust riser is located at the upper right part of the diesel engine piston casting sand mold, and the central exhaust riser is located at the central position of the upper part of the diesel engine piston casting sand mold.

Preferably, the gap width of the gap type lower cross gate ranges from 10 mm to 20 mm.

Preferably, the upper cross runner is arranged at the position of 1/3-1/4 of the height of the vertical runner.

Compared with the prior art, the utility model have following advantage and beneficial effect:

1. the utility model discloses an large-scale diesel engine piston casting sand mould structure, through adopting the ladder pouring runner of watering perpendicularly, going up the runner and the gap formula is watered, reasonable chill, gas rising head are arranged, have realized piston spare sequential solidification technology, and the foundry goods solidifies from supreme successive layer down, and the feeding passageway is unobstructed all the time, and the foundry goods constantly obtains the metal liquid at the solidification in-process and supplyes, shifts various defects to the gas rising head, has eliminated the casting effectively and has solidified the defect.

2. The utility model has reasonable design, simple structure and convenient operation, and the step runner realizes sequential pouring, forms temperature gradient and is smoothly solidified; the arrangement of the chilling blocks can ensure that the piston has better quality near the top working surface of the combustion chamber and the pin boss of the piston.

3. The utility model discloses effective and practical has effectively improved the quality and the yield of product, has improved production efficiency, has reduced manufacturing cost, and bigger ground has satisfied the market demand, has won good economic benefits for the enterprise.

Drawings

FIG. 1 is a three-dimensional axial side view of a schematic diagram of a piston casting sand mold structure of large diesel engines;

FIG. 2 is a schematic illustration of the cross-sectional view of FIG. 1 taken along the center line of symmetry of the piston casting.

Detailed Description

The present invention will be described in further detail in with reference to examples and drawings, but the present invention is not limited thereto.

Example 1

As shown in figures 1 and 2, large diesel engine piston casting sand mould structures comprise a gap type lower cross gate 1, a vertical gate 2, an upper cross gate 3, a left exhaust riser 4, a sand box 5, a central exhaust riser 6, a right exhaust riser 7, pin hole annular chills 8 (two), half-and-half annular chills 9 and a bottom circular chiller 10, wherein when the figure 1 and the figure 2 are viewed correspondingly, the bottom circular chiller 10 is arranged at the bottom of the sand box 5, half-and-half annular chills 9 are combined into rings and are arranged around the lower part of a diesel engine piston casting, a gap type lower cross gate 1 with a gap width ranging from 10 mm to 20mm is formed at a butt joint position, namely a metal liquid inflow port, a plurality of pin hole annular chills are symmetrically distributed, in the embodiment, the two pin hole annular chills 8 are arranged at corresponding positions of piston pin holes, two sides of the pin hole annular chills are respectively , the upper cross gate 3 vertically connects the vertical gate 2 with each other and is communicated with the upper space of the diesel engine piston casting sand mould, the diesel engine upper cross gate 3 is arranged at a position 1/3-height of the vertical gate 2, the diesel engine piston casting sand mould, the right piston casting sand mould 3, the left exhaust riser and the left piston casting sand mould 4-piston casting sand mould riser are arranged at a position, the upper part of the diesel engine piston casting sand mould.

The pouring system is composed of a vertical pouring channel 2, an upper pouring channel 3 and a gap type lower pouring channel 1 to form a ladder pouring runner. During casting, nodular cast iron casting metal liquid is poured from the upper opening of the vertical pouring channel 2, and the metal liquid firstly enters the diesel engine piston casting sand mold from the gap type lower horizontal pouring channel 1. And the liquid level in the sand mold is gradually raised in the pouring process, and when the liquid level reaches the height of the upper cross runner 3, the metal liquid starts to transversely flow into the diesel engine piston casting sand mold from the upper cross runner 3 until the metal liquid is filled in the diesel engine piston casting sand mold. And in the process of flowing the metal liquid into the diesel engine piston casting sand mould, air in the casting sand mould is discharged from the left exhaust riser 4, the right exhaust riser 7 and the central exhaust riser 6 respectively. Because the metal fluid entering the sand mold from the slit type lower cross runner 1 is at the lower part of the sand mold, the cooling is started from the time, and then the metal fluid entering the sand mold from the upper cross runner 3 is at the upper part, and the time difference exists after the cooling starting time is shorter; and because the bottom of the sand box 5 is the round chill 10, two semi-annular chills 9 are around the lower part, the cooling speed of the lower part is fast; the two factors cause that the temperature of the lower part of the casting mold is lower, the temperature of the upper part of the casting mold is higher, a temperature gradient from bottom to top is formed, so that the metal material in the casting mold is solidified from bottom to top and gradually progresses to solidification, sequential solidification is realized, the material on the upper part of the piston can continuously feed the material solidified first on the lower part, the casting defects of shrinkage porosity and shrinkage cavity are eliminated, and the quality of the casting is ensured. The two pin hole annular chills 8 can enable materials around the piston pin hole to be solidified first, and the quality of the pin hole is guaranteed.

Claims

The piston casting sand mold structure of the large diesel engine is characterized by comprising a sand mold, a gap type lower transverse pouring gate, a vertical pouring gate, an upper pouring gate, a plurality of air risers, a pin hole annular chiller, half-and-half annular chills and a bottom circular chiller, wherein the bottom circular chiller is arranged at the bottom of the sand mold, the half-and-half annular chills are combined into rings and arranged around the lower part of a position where a piston casting of the diesel engine is located, the gap type lower transverse pouring gate is formed at a butt joint position to serve as a molten metal inflow port, the plurality of pin hole annular chills are symmetrically distributed and arranged at positions corresponding to pin holes of the piston of the diesel engine, the upper pouring gate is communicated with the vertical pouring gate and communicated with the upper space of the piston casting sand mold of the diesel engine, the vertical pouring gate, the upper pouring gate and the gap type lower transverse pouring gate form a step pouring.
2. The large diesel engine piston casting sand mold structure according to claim 1, wherein the left exhaust riser (4) is located at the upper left portion of the diesel engine piston casting sand mold, the right exhaust riser (7) is located at the upper right portion of the diesel engine piston casting sand mold, and the central exhaust riser (6) is located at the center position of the upper portion of the diesel engine piston casting sand mold.
3. The large diesel engine piston casting sand mold structure according to claim 1, wherein the gap width of the gap type lower cross runner is 10-20 mm.
4. The large diesel engine piston casting sand mold structure according to claim 1, wherein the upper cross runner is arranged at a position 1/3-1/4 of the height of the vertical runner.