CN101927329B

CN101927329B - Vacuum high-pressure casting method

Info

Publication number: CN101927329B
Application number: CN2010102727811A
Authority: CN
Inventors: 龙思远; 徐绍勇; 刘伟召
Original assignee: Chongqing Shuolong Science and Technology Co Ltd
Current assignee: Chongqing Shuolong Science and Technology Co Ltd
Priority date: 2010-09-06
Filing date: 2010-09-06
Publication date: 2012-05-30
Anticipated expiration: 2030-09-06
Also published as: CN101927329A

Abstract

The invention relates to a vacuum high-pressure casting process method for a wheel disc casting. The method comprises the following steps of: after melt casting is finished, sequentially and centripetally filling a model from a wheel flange to a wheel center through a broken ring-shaped runner and a tangential ingate with the assistance of vacuum; and after model filling is finished, jointly pressurizing by a pressure head and a pressure filling head which is positioned on an epitaxial slag ladle of the wheel center and maintaining the pressure till a casting is fully solidified to obtain a high-quality wheel disc casting which has the advantages of high-quality wheel flange model filling and no solidification contraction and blowhole defect on a wheel flange hot spot and a wheel center hot spot.

Description

A kind of vacuum high-pressure casting method

Technical field

The present invention relates to a kind of vacuum high-pressure casting process of producing the wheel disc class foundry goods (like motorcycle and electric boosted wheel hub, belt pulley, gear etc.) that thermal center is scattered in wheel rim and core wheel.

Technical background

Traditional wheel disc class foundry goods, particularly wheel hub, belt pulley etc. all adopt metal mold gravity casting, have problems such as the melt recovery rate is low, production efficiency is low, yield rate is low.In order to adapt to requirements of mass production, improve recovery rate, production efficiency and yield rate, a large amount of light-alloy wheel disc class foundry goods begins to adopt high-pressure casting production at present.

At present, all adopt center pouring technology (seeing accompanying drawing 1) during the high-pressure casting of wheel disc class foundry goods.Since such foundry goods thermal center dispersed and distributed wheel rim with the wheel in the heart; When type die casting is filled at the center; Pressure head can only provide effective feeding for the core wheel thermal center; And be distributed on the wheel rim thermal center because of thin-walled spoke or disc early frozen plug feeding passage solidification shrinkage defectives such as shrinkage cavity is loose appear, significantly reduced the technological quality and the mechanical performance at these positions.

In addition, wheel rim is the region of high stress of wheel disk-like accessory, and it is the highest to require to fill the type quality.But pouring technology last filling wheel rim in center causes forming defects such as oxidizing slag, cold shut, current mark to be concentrated and appears on the wheel rim, has reduced the technological quality and the mechanical performance of foundry goods.

In order to improve the military service performance, after part wheel disc class foundry goods is hoped casting, promote the bulk material mechanical performance through heat treatment.At this moment, require foundry goods at the vacuum lower charging type, but to obtain the Technology for Heating Processing performance.

Summary of the invention

The purpose of the method for the present invention is that provide a kind of melt filling process order rationally, can be simultaneously to the die-casting process method of wheel rim and core wheel feeding, the heat treatable wheel disc class foundry goods that can on widely used horizontal plunger die casting machine, implement.

For realizing above-mentioned purpose, technical scheme of the present invention is: alloy melt (4) quantitatively injects pressure chamber (2) through sprue gate (1), pressure head (3) moves ahead and vacuumizes after sealing sprue gate (1) constitutes near closed hollow ring; In the cavity filling process, pressure head (3) vacuum of accomplishing wheel rim, spoke or disc, core wheel successively that continues to move ahead is filled type, and finishes to vacuumize before type is accomplished filling; After filling the type completion, pressure head (3) solidifies the interior melt (4) of die cavity with ftercompction head (6) pressurization and pressurize under pressure.

In the vacuum pressing and casting process, pressure head (3) experience is filled type, pressurization and pressurize and is solidified three phases; After pressure head (3) moves ahead sealing sprue gate (1), begin die cavity is vacuumized, and before filling the type completion, finish to vacuumize; After filling the type completion; Pressure head (3) and ftercompction head (6) pressurize and pressurize together; In the consecutive solidification of die cavity melt (4), make the thermal center that is distributed in spoke or disc two ends all obtain good feeding according to first spoke or disc, rear rim and core wheel; Eliminate the solidification shrinkage defective of these heat energy-saving positions, like shrinkage porosite, shrinkage cavity etc.

The inventive method has following effect:

1, adopt vacuum aided, the formation of pore in oxidation when having avoided alloy melt (4) flowing forming and the foundry goods has improved the processing quality of wheel disc class foundry goods, and can promote performance through heat treatment;

2, adopt annularly flow to fill type, make the first wheel rim of melt (4), again spoke or disc, the order of core wheel, last slag trap is filled type again, on the high wheel rim of performance requirement, obtain technological quality high and consistent fill the type quality;

3, adopt pressure head (3) and ftercompction head (6) respectively to wheel rim and core wheel pressurization and pressurize, realize the consecutive solidification of first spoke or disc, rear rim and core wheel, thereby be that spoke (dish) thickness, the raising stock utilization that further reduces the wheel disc foundry goods creates conditions;

4, adopt pressure head (3) and ftercompction head (6) the also mode of pressurize of pressurizeing together; Make the melt (4) that is distributed in the thermal center of spoke two ends all obtain good feeding when solidifying; Eliminated the shrinkage cavity rarefaction defect that these positions are easy to occur, guaranteed that foundry goods is fine and close consistent with technological quality;

5, this technology is applicable to widely used horizontal plunger die casting machine.

Description of drawings

Accompanying drawing is the inventive method operation principle sketch map: wherein:

Fig. 1 is a metal mold compression casting sketch map;

Fig. 2 is the Vacuum Die Casting Mould sketch map;

Fig. 3 is the wheel hub drawing of rough casting;

Fig. 4 fills the type precedence diagram for wheel hub evacuated die-casting process;

Fig. 5 solidifies precedence diagram for wheel hub evacuated die-casting process.

Wherein: the 1-sprue gate; 2-presses the chamber; The 3-pressure head; The 4-alloy melt; The 5-cross gate; 6-ftercompction head; The 7-slag trap; 8-ingate 1; 9-ingate 2; 10-ingate 3; 11-spoke top; 12-spoke root.

The specific embodiment

Do further explanation below in conjunction with accompanying drawing and embodiment:

Embodiment is an example with the vacuum die casting process of hub of motorcycle.This process using vertical-parting, annular tangential vacuum are filled type, center ftercompction mode, and its technical process is:

1, vacuum high-pressure fills type: alloy melt (4) quantitatively injects pressure chamber (2) through sprue gate (1), extrusion head (3) moves ahead and vacuumizes after sealing sprue gate (1) constitutes near closed hollow ring; Pressure head (3) continues to move ahead and accomplishes the type that fills of wheel rim, spoke and core wheel successively, and before filling the type completion, finishes to vacuumize; Cavity filling process is seen Fig. 4.

2, compression solidification: after filling the type completion, pressure head (3) solidifies die cavity alloy melt (4) with ftercompction head (6) pressurization and pressurize under pressure; Process of setting is seen Fig. 5.

3, die sinking pickup: the hub of motorcycle casting solidification also stays mould die sinking after a period of time, and pressure head in the time of die sinking (3) and ftercompction head (6) move ahead, and eject stub bar and motor vehicle wheel hub casts, then station before backhaul to the die casting of pressure head (3) and ftercompction head (6) difference;

4, level mould, swabbing, matched moulds, hub of motorcycle vacuum aided extrusion process gets into next circulation.

The light-alloy wheel disc class foundry goods that adopts the inventive method to produce magnesium, Al-alloy motorcycle wheel hub and have similar thermal center distribution characteristics, can solve effectively be prone to oxidation in the melt filling process process, be easy to produce pore, feeding bad, thin disc hub of motorcycle in spoke two ends is difficult to, horizontal plunger die casting machine low with existing casting method production, spoke material utilization rate and can not produces problems such as hub of motorcycle.

Claims

1. wheel disc class foundry goods vacuum high-pressure casting method is: the sealing that moves ahead of preheating casting mold, swabbing → matched moulds → melt cast → pressure head is pressed chamber cast gate → vacuumize → fill type and finish to vacuumize → margin and center compression solidification → die sinking → taking-ups foundry goods simultaneously, it is characterized in that: alloy melt (4) quantitatively injects through sprue gate (1) and vacuumizes after pressing chamber (2), pressure head (3) to move ahead to seal sprue gate (1) formation near closed hollow ring; Pressure head (3) continues to move ahead and accomplishes wheel disc outer rim, wheel disc spoke or disc successively, and the order of last core wheel is entad filled type, and before filling the type end, stops vacuumizing; After filling the type completion; Pressure head (3) is with center ftercompction head (6) pressurization and pressurize, and the melt in die cavity (4) solidifies under pressure fully, and cross gate (7) is to be positioned at the outer abscission ring structure of wheel rim; The ingate tangential is opened between wheel rim and the cross gate; The position of ingate, size guarantee alloy melt (4) wheel rim of rotation filling earlier under the ordering about of pressure head (3), and then while each spoke of filling or disc, come together in the slag trap of core wheel extension behind the last filling core wheel; Realize first wheel rim, again spoke or disc, the order of core wheel, last slag trap is filled type again, center ftercompction head is positioned at the top of core wheel slag trap.

2. vacuum high-pressure casting method according to claim 1; It is characterized in that: after filling the type completion; Pressure head (3) and be positioned at the common pressurization of ftercompction head (6) and the pressurize on core wheel slag trap top; Melt (4) on the thermal center that is distributed in wheel rim and core wheel is solidified under pressure, and obtaining wheel rim and core wheel does not all have solidification shrinkage defective, integral body not to have the sound casting of pore.