KR102157387B1 - Manufacturing method for scroll and forging apparatus thereof - Google Patents

Abstract

According to the present invention, a scroll manufacturing method includes: a dissolving step (a) of dissolving an aluminum alloy comprising 8-16 wt% of silicon (Si), 1-7 wt% of copper (Cu), 0.1-2 wt% of magnesium (Mg), 0.05-2 wt% of manganese (Mn), 0.01-3 wt% of nickel (Ni), less than 0.05 wt% of an individual content of inevitable impurities and the remaining of aluminums; a vertical consecutive casting step (b) of manufacturing a narrow rod with the dissolved aluminum alloy; a homogeneous processing step (c) of removing macro segregation from the casted narrow rod; a surface processing step (d) of processing the surface of the homogeneously processed narrow rod; a step (e) of manufacturing forging slug by cutting the surface-processed narrow rod; a solid lubrication step (f) of applying a lubricant to the surface of the forging slug; a heating step (g) of heating the forging slug with the lubricant applied to the surface thereof; and a step (h) of placing the heated forging slug in a lower mold, and forging the same by pressing the same with an upper mold including a formation space and a liquid lubricant supply line. Therefore, the scroll manufacturing method is capable of increasing efficiency in a scroll production process.

Description

Scroll manufacturing method and scroll forging device according thereto {MANUFACTURING METHOD FOR SCROLL AND FORGING APPARATUS THEREOF}

The present invention relates to a method and apparatus for manufacturing a scroll. More specifically, the present invention relates to a scroll manufacturing method using the back molding forging and a scroll manufacturing method using the same.

The demand for electric vehicles is also increasing as the activation of the electric vehicle industry has been selected as a key policy of various countries as a way to solve social issues such as global environment conservation, energy saving and fine dust. Therefore, the demand for scroll compressors used as air conditioning compressors for electric vehicles is also increasing year by year. In particular, since scrolls are products that require durability, aluminum alloys that require high strength, wear resistance, and thermal stability are produced by applying the forging method.

1 is a perspective view of a scroll having a pin formed thereon, FIG. 2 is a side cross-sectional view of the scroll, and FIG. 3 is a plan view of the scroll.

1 to 3, the scroll 10 is composed of a scroll-shaped pin 1 and a flange 2, and the cross section is narrow and the length is long, and the width between the pins is narrow, making forging difficult.

Conventional scroll forging machines consist of a structure in which an upper mold for pressurization is installed on a ram that moves for pressurization, and a lower mold having a molding cavity in which a forged slug to be used for molding is placed is fixed at the lower part. And, when the upper mold installed in the ram of the forging machine presses the forged slug, it is manufactured by flowing the forged slug in the pressing direction to fill the forming space of the lower mold.

The shape of the scroll is very difficult for forging molding because the pins are thin and long and the width between the pins is narrow.In the case of manufacturing by the conventional forging method, the scroll is not uniformly formed, the forging pressure increases, and the forging mold There is a problem of shortening the lifespan.

4 is a schematic diagram showing the pressure applied to the forged slug.

Referring to FIG. 4, when the scroll is formed by a conventional forging method, the forged slug pressed as in FIG. 4 forms a dead zone in which metal does not flow due to friction with the surface of the mold in contact. do. The formation of such dead zones neutralizes the effect of lubrication coating on the surface of the slug and the surface of the mold.

In addition, lubrication of the mold surface using the spray method is not possible to lubricate to the final depth of the mold forming the scroll pin, and not only lowers the temperature of the mold, but also shortens the mold life due to seizure between the scroll and the mold surface. have. In addition, it impairs the working environment and causes a problem of exposing workers to hazardous substances.

In order to compensate for this problem, a scroll manufacturing method using back pressure forging technology has been introduced, but the cost of equipment and molds is high, and productivity is low, so there is a problem of economical efficiency.

As a prior document related to this, in Korean Patent No. 10-0461282, a back pressure molding apparatus and a molding method for hot forging of an AL alloy scroll rotor (announced on December 14, 2004) are disclosed.

It is an object of the present invention to form a lubricating coating on the surface of a forged slug by using a rear molding forging technology and a continuous lubrication technology to form a lubricating coating on the surface of the forging slug. By offsetting the frictional force formed between the slugs and preventing the formation of metal flow dead zones, the initial forging pressure is lowered by the action of the lubricating film formed on the surface of the forged slug, thereby preventing uneven forming of the scroll and suppressing the increase in forging pressure. It is to provide a way.

Another object of the present invention is to design an aluminum alloy for manufacturing a scroll that requires high strength, excellent wear resistance, and thermal stability, and to provide a method for manufacturing a scroll using the same.

Another object of the present invention is that when an upper mold including an upper mold having a liquid lubricant supply line directly presses the forged slug and the metal flow fills the scroll forming space of the upper hole, the liquid lubricating film formed on the surface of the mold is at an initial forging pressure. It is to provide a scroll forging device that prevents the rise of the mold so that a uniform scroll can be formed, and also prevents seizure between the molded scroll and the mold to significantly improve the life of the mold.

All of the above and other objects of the present invention can be achieved by the present invention described below.

One aspect of the present invention relates to a method of manufacturing a scroll. In a specific example

(a) Silicon (Si): 8 to 16 wt%, Copper (Cu): 1 to 7 wt%, Magnesium (Mg): 0.1 to 2 wt%, Manganese (Mn): 0.05 to 2 wt%, Nickel (Ni ): 0.01 to 3% by weight, and an individual content of the inevitable impurities does not exceed 0.05% by weight, and a melting step of dissolving an aluminum alloy whose balance is aluminum;

(b) vertical continuous casting step of manufacturing a small diameter rod from the molten aluminum alloy;

(c) a homogeneous treatment step of removing macro segregation of the cast fine-gyeongbong;

(d) a surface processing step of processing the surface of the small diameter rod subjected to homogeneous treatment;

(e) manufacturing a forged slug by cutting the surface-processed small diameter rod;

(f) a solid lubrication step of applying a lubricant to the surface of the forged slug;

(g) a heating step of heating the forged slug coated with a lubricant on the surface; And

(h) seating the heated forged slug on a lower mold, and forging by pressing it with an upper mold having a molding space and a liquid lubricant supply line.

In addition, in the melting step, the aluminum alloy further contains 0.1 to 0.5% by weight of strontium (Sr) when the content of silicon (Si) is 12% by weight or less, and 0.01 to phosphorus (P) when it exceeds 12% by weight. It may further contain ~0.1% by weight.

In addition, the vertical continuous casting step is a gas pressure casting method in which the molten aluminum alloy is pressurized with an inert gas and supplied to a mold, and a small diameter rod having a diameter of 100 mm or less may be vertically continuously cast.

In addition, after the step of forging by pressing with the upper mold, the scroll can be heated to 480 to 510°C and cooled with water, and then reheated to 180 to 250°C and maintained for 4 to 10 hours.

In addition, the scroll, which has been subjected to solution treatment and aging heat treatment, may have a tensile strength of 405 to 435 MPa, a yield strength of 345 to 390 MPa, and a hardness of 80 to 85 HRB.

Another aspect of the present invention is a scroll forging apparatus comprising a lower mold and an upper mold having a forming space and a liquid lubricant supply line,

A base having a guide hole formed in the center and provided with a plurality of vertical guides along the outer circumference;

A lower mold disposed on the base and having a forming chamber in which the heated forged slug is seated, a scroll flange forming groove formed at one side of the forming chamber, and an eject hole communicating with the guide hole formed at a center thereof;

A lower eject pin having one end fastened to the guide hole, moving along the eject hole and pressing the forged slug to raise the formed scroll;

A ram that is fastened to the vertical guide and moves vertically;

A holder mounted under the ram and having a circular ring shape;

Supported by the holder, a through hole is formed inside, a liquid lubrication supply space is provided at one side of the through hole, and a scroll pin forming groove is formed at one end of the through hole to pressurize the forged slug to allow the metal flowing into the inside. An upper mold that is introduced to form a scroll pin; And

It provides a scroll forging device that is mounted to be movable vertically in the through hole, and includes an upper eject pin for pressing and discharging the scroll on which the scroll pin is formed.

In addition, the scroll pin forming groove may be formed in a circular or spiral shape.

In addition, a liquid lubricant supply line may be provided at one side of the through hole.

In addition, the liquid lubricating oil supply line is connected to a lubricating supply device formed by a lubricating pump and an injector device outside the upper mold, and may have a lubricating hole through which lubricating oil can be injected into the liquid lubricating supply space at one side of the through hole. have.

In addition, the liquid lubricating oil supply line may continuously supply lubricating oil between the upper ejection pin and the through hole when the upper ejection pin moves vertically.

In addition, the liquid lubricant supply line forms an oil film on the inner surface of the through hole by injecting lubricant into the through hole, and the scroll pin is formed when the upper eject pin descends to discharge the scroll on which the scroll pin is formed. An oil film can be formed on the inner surface of the groove.

In addition, the inner surface of the scroll pin forming groove may have an inclined surface that is more than 0° and not more than 5° outward from the vertical center.

The present invention provides an aluminum alloy having high strength, excellent wear resistance and thermal stability.

In addition, it is possible to increase the efficiency of the scroll production process by continuously producing small diameter rods through a continuous casting process, cutting them and lubricating them.

In addition, it is possible to reduce the friction between the mold and the forged slug to prevent the formation of a dead zone in which metal flow does not occur, and to reduce the forging pressure by forming an oil film on the surface of the forged slug.

In addition, the automatic liquid lubrication of the upper mold can prevent seizure during molding or between the molded scroll and the upper mold by forming a lubricating film on the inner wall of the mold of the scroll forming groove, thereby greatly improving the working environment than the conventional spray method.

In addition, it is possible to prevent uneven molding of the scroll, and it is possible to solve the problem of shortening the mold life due to an increase in forging pressure.

1 is a perspective view of a scroll with pins formed thereon.
2 is a side cross-sectional view of the scroll.
3 is a plan view of the scroll.
4 is a schematic diagram showing the pressure applied to the forged slug.
5 is a flowchart of a method for manufacturing a scroll according to an embodiment of the present invention.
6 is a cross-sectional view of a scroll forging apparatus according to an embodiment of the present invention and a partially enlarged view of a liquid lubricant supply line.
7 is an exploded perspective view showing a coupling relationship between an upper mold and a lower mold of the scroll forging apparatus according to an embodiment of the present invention.
8 is a cross-sectional view showing a state in which the upper mold descends and presses the forged slug to form a scroll in another scroll forging apparatus according to one embodiment of the present invention.
9 is a cross-sectional view showing a state in which the upper mold is separated after scroll forming in the scroll forging apparatus according to an embodiment of the present invention and a partial enlarged view of the scroll pin forming groove.
10 is a cross-sectional view showing a state in which an upper eject pin is lowered to discharge a molded scroll in a scroll forging apparatus according to an embodiment of the present invention, and a partial enlarged view of a scroll pin forming groove.
11 is a partial cross-sectional view showing a liquid lubricant supply line and a scroll pin forming groove of a scroll forging apparatus according to an embodiment of the present invention according to a forging process sequence.
12 is a photograph of a scroll manufactured in a scroll forging apparatus according to an embodiment of the present invention.
13 is an optical microscopic microstructure photograph of the produced aluminum alloy structure in a method for manufacturing a scroll according to an embodiment of the present invention.

Hereinafter, the present invention will be described in more detail with reference to the accompanying drawings. However, the following drawings are provided only to aid understanding of the present invention, and the present invention is not limited by the following drawings. In addition, the shape, size, ratio, angle, number, etc. disclosed in the drawings are exemplary, and the present invention is not limited to the illustrated matters.

The same reference numerals refer to the same components throughout the specification. In addition, in describing the present invention, when it is determined that a detailed description of related known technologies may unnecessarily obscure the subject matter of the present invention, the detailed description thereof will be omitted.

When'include','have','consists of' and the like mentioned in the present specification are used, other parts may be added unless'only' is used. In the case of expressing the constituent elements in the singular, it includes the case of including the plural unless specifically stated otherwise.

In interpreting the constituent elements, it is interpreted as including an error range even if there is no explicit description.

If the positional relationship of the two parts is described as'on the top','the top of the','the bottom of the', the'next to', etc., between the two parts unless'direct' or'direct' is used. One or more different parts may be located.

Positional relationships such as'upper','upper','lower', and'lower' are only described based on the drawings, and do not represent absolute positional relationships. That is, depending on the position to be observed, the positions of the'upper' and'lower' or the'upper' and'lower' may be changed to each other.

Hereinafter, a method of manufacturing a scroll according to an exemplary embodiment of the present invention will be described with reference to the drawings.

5 is a flowchart illustrating a method of manufacturing a scroll according to an exemplary embodiment of the present invention.

5, the scroll manufacturing method in one embodiment of the present invention

(a) Silicon (Si): 8 to 16 wt%, Copper (Cu): 1 to 7 wt%, Magnesium (Mg): 0.1 to 2 wt%, Manganese (Mn): 0.05 to 2 wt%, Nickel (Ni ): 0.01 to 3% by weight, and the individual content of the inevitable impurities does not exceed 0.05% by weight and the remaining aluminum alloy is dissolved in a melting step;

(b) vertical continuous casting step of manufacturing a small diameter rod from the molten aluminum alloy;

(c) a homogeneous treatment step of removing macro segregation of the cast fine-gyeongbong;

(d) a surface processing step of processing the surface of the small diameter rod subjected to homogeneous treatment;

(e) manufacturing a forged slug by cutting the surface-processed small diameter rod;

(f) a solid lubrication step of applying a lubricant to the surface of the forged slug;

(g) a heating step of heating the forged slug coated with a lubricant on the surface; And

(h) seating the heated forged slug on a lower mold, and forging by pressing it with an upper mold having a molding space and a liquid lubricant supply line.

First, silicon (Si): 8-16 wt%, copper (Cu): 1-7 wt%, magnesium (Mg): 0.1-2 wt%, manganese (Mn): 0.05-2 wt%, nickel (Ni): A molten metal is prepared by dissolving an aluminum alloy whose individual content of 0.01 to 3% by weight and inevitable impurities does not exceed 0.05% by weight and the remainder is aluminum (S100).

When the silicon (Si) is added within the above range, the fluidity of the molten metal and the abrasion resistance of the manufactured scroll may be improved.

The copper (Cu) and magnesium (Mg) may improve the mechanical strength of the scroll.

If the content of copper (Cu) and magnesium (Mg) is out of the range, the target mechanical strength cannot be obtained.

The manganese (Mn) and nickel (Ni) may increase the thermal stability of the scroll.

The manganese (Mn) and nickel (Ni) may be optionally added.

When the content of manganese (Mn) and nickel (Ni) is out of the range, it is difficult to increase the thermal stability of the scroll manufactured by hot forging.

Each of the inevitable impurities is 0.05% by weight or less.

The inevitable impurity refers to a component that is inevitably incorporated when designing an aluminum alloy.

When impurities exceeding the above range are contained, there is a concern that mechanical properties of the scroll may decrease during manufacture of the scroll.

On the other hand, in the melting step, the aluminum alloy further contains 0.1 to 0.5% by weight of strontium (Sr) when the content of silicon (Si) is less than 12% by weight, and 0.01 to phosphorus (P) when it exceeds 12% by weight. It may further contain 0.1% by weight.

When the silicon (Si) content is less than 12% by weight, eutectic Si may be improved by adding strontium (Sr) within the above range.

When the content of silicon (Si) exceeds 12% by weight, phosphorus (P) within the above range may be added to refine primary Si.

When the process silicon is improved and the super-normal silicon is refined, the mechanical properties of the scroll manufactured by hot forging can be increased.

In the vertical continuous casting step, a small diameter rod is manufactured from dissolved aluminum alloy (S200).

The vertical continuous casting step is a gas pressure casting method in which the molten aluminum alloy is pressurized with an inert gas and supplied to a mold, and a small diameter rod having a diameter of 100 mm or less may be vertically continuously cast.

The gas pressure casting method can be processed by pressurizing the molten metal of an aluminum alloy with an inert gas and transferring it to a mold, and can maintain the physical properties of the aluminum alloy.

The vertical continuous casting has a fast solidification rate, and can maximize and maintain the physical properties of the aluminum alloy designed by continuously manufacturing small diameter rods of 100 mm or less in diameter.

It is possible to efficiently manufacture a small diameter rod with the molten metal of aluminum alloy designed through the gas pressure casting method and the vertical continuous casting step.

The homogeneous treatment step removes the macro segregation of the cast thin-bar (S300).

When the macro segregation is removed in the homogeneous processing step, since the internal stress is removed and the structure is uniform, hot forging is possible.

The homogenization treatment step may be preheated to a high temperature sequentially to homogenize macro segregation.

In the surface processing step, the surface of the small diameter rod subjected to a homogeneous treatment is processed (S400).

In the surface processing step, the surface of the small-diameter rod is cut to remove defects on the casting surface, and the surface is processed to a required diameter.

The surface processing step may increase the efficiency of the subsequent cutting process.

The forged slug is manufactured by cutting the surface-processed small diameter rod (S500).

The forged slug can be manufactured by cutting the small diameter rod into a length corresponding to the weight of the scroll.

In the solid lubrication step, a lubricant is applied to the surface of the forged slug (S600).

In the solid lubrication step, a chemical conversion film and a lubricating film may be formed by immersing the forged slug in a tank containing lubricating oil.

Here, the solid lubrication step may further include a water washing process, a pickling process, and a drying process.

When performing the water washing and pickling process, the effect of the solid lubrication step is increased.

The heating step heats the forged slug coated with a lubricant on the surface (S700).

The forging slug may be heated to perform a hot forging process.

The heated forged slug is seated on a lower mold, and the forging process is performed by pressing it with an upper mold having a forming space and a liquid lubricant supply line (S800).

The upper mold has a molding space and a liquid lubricant supply line.

A lower mold having a space corresponding to the molding space of the upper mold may be provided.

The metal of the forged slug flows into the molding space of the upper mold and is introduced.

The forging process is a rear molding forging process in which a flowing metal formed by pressing a forged slug flows in a direction opposite to the pressing direction of the upper mold.

The liquid lubricating oil supply line introduces liquid lubricating oil into the molding space.

The liquid lubricant supply line may supply lubricant to the outside of an eject pin provided in the molding space together with the molding space.

When lubricating oil is introduced into the molding space to form an oil film, the pressure generated when the forged slug is pressed can be reduced, and seizure of the forged slug and the upper mold can be prevented.

The upper mold presses the forged slug to form a scroll, and when the eject pin pushes the scroll as the upper mold is spaced apart, liquid lubricant is automatically supplied and flows down with the discharged scroll to form an oil film on the inner wall of the mold. The scroll can be discharged from the upper mold and finally separated from the lower mold.

The liquid lubricating oil supply line may continuously supply lubricating oil to the molding space to continuously perform a scroll forging process.

The liquid lubricating oil supply line supplies lubricating oil to the molding space to reduce the friction between the forged slug introduced into the molding space and the inner surface of the molding space of the upper mold, thereby reducing the initial forging pressure and preventing seizure with the mold. It can dramatically increase the life of the mold.

The rear molding forging step can prevent dead zone formation, which is a disadvantage of conventional forging, and can increase the life of the mold by using the liquid lubricant supply line, as well as eliminate the spray-type mold lubrication method. It provides a method to automatically manufacture scrolls that do not harm the environment and the health of workers.

Meanwhile, after the step of forging by pressing with the upper mold, the scroll may be heated to 480 to 510°C and cooled with water, and then reheated to 180 to 250°C and maintained for 4 to 10 hours.

The aging heat treatment process may increase mechanical properties such as tensile strength and hardness of the scroll.

After the forging process, the scroll manufactured by solution treatment and aging heat treatment may exhibit mechanical properties having a tensile strength of 405 to 435 MPa, a yield strength of 345 to 390 MPa, and a hardness of 80 to 85 HRB.

Therefore, the scroll manufacturing method according to one embodiment of the present invention is an optimal aluminum alloy capable of forming molten metal in the melting step and increasing mechanical properties such as tensile strength, yield strength and hardness as well as thermal stability during forging processing. After designing and preparing to perform hot forging through vertical continuous casting step, shaving step, cutting step, solid lubrication step and heating step, using a forging device including an upper mold equipped with a liquid lubricating oil supply line, It is possible to prevent the formation of a dead zone, which is a problem, and to continuously manufacture a scroll.

Another aspect of the present invention is a scroll forging apparatus comprising an upper mold having the lower mold, the molding space, and a liquid lubricant supply line,

A base 100 having a guide hole 110 formed in the center and provided with a plurality of vertical guides 120 along the outer circumference; A forming chamber 210 is formed on the top of the base 100 and in which the heated forged slug 800 is seated, and a scroll flange forming groove 220 is formed on one side of the forming chamber 210, and the center A lower mold 200 in which an eject hole 220 communicating with the guide hole 110 is formed; A lower eject pin 300 having one end fastened to the guide hole 110 and moving along the eject hole 220 and pressing the forged slug 800 to lift the formed scroll 810; A ram 400 that is fastened to the vertical guide 120 so as to move vertically; A holder 500 mounted under the ram 400 and having a circular ring shape; Supported by the holder 500, a through hole 610 is formed inside, a liquid lubrication supply space 621 is provided at one side of the through hole 610, and a scroll pin forming groove at one end of the through hole 610 An upper mold 600 having 650 formed to pressurize the forged slug 800 so that the flowing metal flows into the interior to form a scroll pin 811; And it provides a scroll forging device 1000 including an upper ejection pin mounted to be movable vertically in the through hole 610, the scroll pin 811 is formed by pressing the scroll 810 is discharged.

The scroll forging device 1000 is a forging device for applying the scroll manufacturing method described above.

The scroll 810 is provided with a scroll body in the form of a disk, a scroll pin 811 formed in a spiral on one side of the scroll body, and a scroll flange 812 on the other side.

6 is a cross-sectional view of a scroll forging apparatus according to an embodiment of the present invention.

6, the scroll forging device 1000 includes a base 100, a lower mold 200, a lower eject pin 300, a ram 400, a holder 500, an upper mold 600, and It includes an upper eject pin 700.

The base 100 has a guide hole 110 formed in the center, and a plurality of vertical guides 120 are provided along the outer periphery.

The base 100 has a guide hole 110 formed in the center, and the lower eject pin 300 is fastened to the guide hole 110 so as to be vertically movable.

One end of the guide hole 110 has a step, and the head of the lower eject pin 300 is caught in the step, so that the elevation of the lower eject pin 300 may be limited.

The vertical guide 120 supports the ram 400 to be movable so that the ram 400 may vertically move.

The lower mold 200 is disposed on the base 100 and has a forming chamber 210 in which the heated forged slug 800 is seated therein, and a scroll flange forming groove on one side of the forming chamber 210 ( 220) is formed, and an eject hole 220 communicating with the guide hole 110 is formed in the center.

The forming chamber 210 provides a space in which the forged slug 800 is seated, and the forged slug 800 is pressed by pressing the forged slug 800 and changes its shape to form a scroll 810.

The scroll flange forming groove 220 is formed under the forming chamber 210.

When the forged slug 800 is pressed and the metal flows, a part of the metal of the forged slug 800 may flow and move to the scroll flange forming groove 220.

When a part of the metal of the forged slug 800 flows and moves to the scroll flange forming groove 220, a scroll flange 812 is formed under the scroll 810.

The shape of the scroll flange forming groove 220 may be determined according to the state of use of the scroll 810.

The eject hole 220 is formed in the center of the lower mold 200 and communicates with the guide hole 110 to provide a path through which the lower eject pin 300 moves.

The lower eject pin 300 has one end fastened to the guide hole 110, moves along the eject hole 220, and presses the forged slug 800 to raise the molded scroll 810.

Since the lower eject pin 300 can raise the scroll 810, the molded scroll 810 can be easily separated from the lower mold 200.

The ram 400 is fastened to be movable to the vertical guide 120 and moves vertically.

The ram 400 moves vertically along the vertical guide 120, and the ram 400 may control the movement of the upper mold 600.

The holder 500 is mounted under the ram 400 and has a circular ring shape.

One end of the upper mold 600 is fastened and supported in the inner space of the holder 500.

The upper mold 600 is supported by the holder 500 and has a through hole 610 formed therein, a liquid lubricant supply line 620 is provided at one side of the through hole 610, and the through hole 610 ) At one end, a scroll pin forming groove 650 is formed so that the metal flowing by pressing the forged slug 800 flows into the inside to form the scroll pin 811.

The through hole 610 is fastened so that the upper eject pin 700 is movable so that the upper eject pin 700 can move vertically.

The upper mold 600 is disposed to face the lower mold 200, approaches the lower mold 200 according to the movement of the ram 400, and the forged slug seated on the lower mold 200 Press 800.

At this time, the metal of the forged slug 800 flows by the pressure and flows into the scroll pin forming groove 650.

Metal flowing into the scroll pin forming groove 650 forms a scroll pin 811.

Since the metal of the forged slug 800 flows and flows into the scroll pin forming groove 650, the scroll pin 811 is formed in a direction opposite to the pressing direction of the upper mold 600.

One embodiment of the present invention because the metal of the forged slug 800 flows in the reverse direction of the pressing direction of the upper mold 600, and the scroll pin 811 is formed after moving inside the scroll pin forming groove 650 In the example, the scroll is forged by the back molding forging method.

The forward molding and forging method pressurizes the forged slug, flows the metal of the forged slug and flows into the lower mold to form a scroll, but in this case, a dead zone that does not flow during front molding and forging is formed on the surface layer of the forged slug in contact with the lower mold. , Excessive excess pressure for overcoming the dead zone is required, and a pressure difference for flowing the forged slug according to the position and thickness of the scroll pin occurs, thereby forming a non-uniform scroll.

In the forward molding forging method, the problem caused by the dead zone and the lubricant can be applied to the surface of the mold by spraying the lubricant to the lower mold, but the space for forming the scroll is narrow and the length is long, so an oil film on the mold surface of the scroll molding part It is not only difficult to form, but also hinders the work environment due to the spraying operation and causes a problem to the health of the worker.

In one embodiment of the present invention, the metal of the forged slug 800 flows by the pressure of the upper mold 600, so that the rear molding forging is possible to flow into the scroll pin forming groove 650, and the scroll pin forming groove 650 ), the oil film 631 is formed on the mold surface of the space where the scroll is formed by inflow of the lubricant 630, thereby preventing an increase in the initial forging pressure, and the uniform flow of metal accordingly makes it possible to form a uniform scroll. . In addition, the oil film formed on the metal surface can significantly increase the life of the mold by preventing seizure between the flowing metal and the mold surface.

The scroll pin forming groove 650 may be formed in a circular or spiral shape.

The shape of the scroll pin forming groove 650 may be changed according to the design of the scroll pin 811.

Referring to a partially enlarged view of the liquid lubricant supply line 620 of FIG. 6, the liquid lubricant supply line 620 is provided at one side of the through hole 610.

The liquid lubricant supply line 620 includes a liquid lubricant supply space 621 and a discharge port 622.

The liquid lubrication supply space 621 is connected to the lubrication hole 640 of the mold, and the lubrication hole 640 is connected to a lubricant supply device outside the upper mold 600 so that the lubricant 630 is always stored, Lubricating oil 630 is discharged to the through hole 610 through the discharge port 622 by the amount of the supplied lubricating oil controlled by a lubricating pump and an injector, which are external lubrication supply devices of the mold.

The lubricating oil 630 discharged through the through hole 610 may allow the lubricating oil 630 to flow continuously along the through hole 610 to form an oil film 631.

The liquid lubricant supply line 620 may be provided at an upper side of the through hole 610.

The liquid lubricant supply line 620 is provided to supply the lubricant 630 between the upper eject pin 700 and the inner circumferential surface of the through hole 610 to form an oil film 631.

When the upper ejection pin 700 moves vertically, the liquid lubricant supply line 620 inserts the lubricant 630 toward the through-hole 610 to provide the upper ejection pin 700 and the through-hole 610. The lubricating oil 630 may be continuously supplied through the gap.

Since the lubricant 630 can be continuously injected between the upper eject pin 700 and the through hole 610, the lubricant 630 can not only facilitate the movement of the upper eject pin 700, but also It may be transmitted to the scroll pin forming groove 650 provided at one end of the through hole 610.

In the liquid lubricant supply line 620, the lubricant 630 is injected into the through hole 610 so that the lubricant 630 forms an oil film 631 on the inner surface of the through hole 610, and the upper ejection When the pin 700 descends to discharge the scroll 811 and the scroll 810 on which the pin is formed, an oil film 631 may be formed on the inner surface of the scroll pin formation groove 650.

When the lubricant 630 is supplied between the upper eject pin 700 and the through hole 610, the lubricant 630 flows down to the scroll pin forming groove 650 according to the movement of the upper eject pin 700. In addition, an oil film 631 may be formed on the inner surface of the scroll pin forming groove 650.

When the oil film 631 is formed on the inner surface of the scroll pin forming groove 650, forging for forming the scroll 810 may be continuously performed.

7 is an exploded perspective view showing a coupling relationship between an upper mold and a lower mold of the scroll forging apparatus according to an embodiment of the present invention.

Referring to FIG. 7, the upper mold 600 is fastened to and supported by the holder 500.

The lower mold 200 may be provided with a lower mold core 240 and a lower mold holder 250.

The core of the lower mold 200 is inserted into and fastened to the lower mold holder 250.

When the lower mold 200 is provided as a lower mold core 240 and a lower mold holder 250, maintenance of the scroll flange forming groove 220 formed in the lower mold core 240 becomes easy, and the scroll ( The shape of the scroll flange 812 formed under the 810 may be modified.

The lower ejection pin 300 is fastened so as to be vertically movable through the ejection hole 220.

Since the lower ejection pin 300 is movably fastened through the lower mold 200, the scroll 810 formed in the forming chamber 210 is pushed by the lower ejection pin 300 and rises, and then the lower mold Separated at 200 can be discharged.

The upper ejection pin 700 is mounted to be vertically movable in the through hole 610, and presses and discharges the scroll 810 on which the scroll pin 811 is formed.

The upper ejection pin 700 has a form in which a plurality of pins are mounted on a flat plate, and the plurality of pins pass through the through hole 610 by pressing the flat plate to press the scroll 810 formed by forging processing. It can be separated from the upper mold 600.

The scroll pin forming groove 650 is formed at one end of the through hole 610 and the metal flowing by pressing the forged slug 800 flows into the scroll pin forming groove 650 to form the scroll pin 811 do.

The inner surface of the scroll pin forming groove 650 may be provided with an inclined surface 651 that is more than 0° and not more than 5° in an outward direction from the vertical center.

When the scroll pin forming groove 650 is provided with an inclined surface 651 that is more than 0° and 5° or less toward the outside in a vertical center, separation from the formed scroll pin 811 becomes very easy.

An oil film 631 is formed on the inner surface of the scroll pin forming groove 650 to reduce friction during forging and can be separated from the upper mold 600, but an inclined surface 651 is formed in the scroll pin forming groove 650 In this case, it is possible to more easily perform separation and discharge after forming the scroll pin 811.

Hereinafter, a method of operating the scroll forging apparatus 1000 according to an embodiment of the present invention will be described with reference to the drawings.

Referring to FIG. 6, first, when the forged slug 800 is seated in the forming chamber 210, and the lubricant 630 is introduced into the through hole 610 through the liquid lubricant supply line 620, the The lubricant 630 flows down between the through hole 610 and the upper eject pin 700, and an oil film 631 is formed up to the inner surface of the scroll pin forming groove 650 formed at one end of the through hole 610.

When the forging slug 800 is seated in the forming chamber 210 and an oil film 631 is formed on the inner surface of the scroll pin forming groove 650, a preparation process for forging processing is completed.

8 is a cross-sectional view showing a state in which the upper mold of the scroll forging apparatus is lowered and pressurized the forged slug to form a scroll, and FIG. 9 is a scroll forging apparatus according to an exemplary embodiment of the present invention. It is a cross-sectional view showing a state in which the upper mold is separated after scroll forming and a partial enlarged view of the scroll pin forming groove, and FIG. 10 is a view in which the upper eject pin descends and discharges the formed scroll in the scroll forging device according to an embodiment of the present invention. It is a cross-sectional view showing the state and a partial enlarged view of the scroll pin forming groove.

8 to 10, when the ram 400 descends, the upper mold 600 descends accordingly, and a scroll pin forming groove 650 formed at one end of the upper mold 600 forms the forged slug 800. Pressurize.

When the forged slug 800 is pressed, the metal flows in a direction opposite to the pressing direction of the upper mold 600 and flows into the scroll pin forming groove 650.

At this time, the lubricant oil 630 flows down on the inner surface of the scroll pin forming groove 650 to form an oil film 631, and the oil film 631 pressurizes the forged slug 800 to reduce the pressure required for molding, It is possible to prevent seizure of the forged slug 800 and the scroll pin forming groove 650.

Since the lubricant 630 is not sprayed and flows down along the through hole 610 to form an oil film 631 on the inner surface of the scroll pin forming groove 650, the working environment can be greatly improved.

The scroll pin forming groove 650 forms a spiral scroll pin 811 in the scroll body.

Part of the metal of the forged slug 800 flows into the scroll flange forming groove 220 formed under the forming chamber 210 to form the scroll flange 812 at the same time as the scroll pin 811 is formed.

The lowering of the upper mold 600 presses the forged slug 800 to simultaneously form a scroll pin 811 at the top and a scroll flange 812 at the bottom to complete the scroll.

When the scroll 810 is formed by forging and pressing the forged slug 800, the upper mold 600 is spaced apart from the lower mold 200.

The upper mold 600 rises, and the scroll 810 molded by forging processing still exists in a state inserted into the scroll pin forming groove 650.

9, an oil film 631 exists in the scroll pin forming groove 650, and the lubricant 630 flows down between the through hole 610 and the upper eject pin 700. The oil film 631 is formed so that the upper eject pin 700 moves vertically so that the scroll pin 811 can be easily pushed out.

When the upper eject pin 700 is lowered, the scroll 810 is pushed and the scroll 810 is seated on the lower eject pin 300, and when the lower eject pin 300 is raised, molding is performed. The completed scroll 810 is discharged from the lower mold 200.

Referring to the partially enlarged view of FIG. 10, when lubricant is continuously introduced into the through hole 610 from the liquid lubricant supply line 620 and the upper eject pin 700 descends, the upper eject pin 700 Since it flows between the outer circumferential surface and the inner circumferential surface of the through hole 610 to form an oil film 631, and flows down to the inner surface of the scroll flange forming groove 220 to form an oil film 631, it is ready to perform continuous forging processing. Is completed.

When the scroll 810 is discharged, the forging slug 800 is placed in the forming chamber 210 of the upper mold 600 again to repeat the forging process.

11 is a partial cross-sectional view showing the liquid lubricant supply line 620 and the scroll pin forming groove 650 of the scroll forging apparatus 1000 according to an embodiment of the present invention according to the forging process sequence.

When the forging process starts, a controlled amount of lubricant 630 is discharged through the lubricant oil inlet 621 and the discharge port 622 of the liquid lubricant supply line 620.

The lubricant 630 introduced into the through hole 610 forms an oil film 631 on the outer circumferential surface of the upper eject pin 700 and the inner surface of the through hole 610.

The lubricating oil 630 reaches the scroll flange forming groove 220 along the upper eject pin 700, a scroll pin 811 is formed, and the upper eject pin 700 descends to the scroll pin ( 811) and pushed out.

At this time, the lubricant 630 reaches the inner surface of the scroll flange forming groove 220 to form an oil film 631 on the inner surface, and the friction between the scroll flange forming groove 220 and the forged slug 800 in the next forging process By reducing the value, it is possible to prevent an increase in initial forging pressure and effectively prevent seizure between the mold and the flowing metal.

12 is a photograph of a scroll and a scroll pin forming groove manufactured in a scroll forging apparatus according to an embodiment of the present invention.

Referring to FIG. 12, the scroll forging apparatus 1000 according to an exemplary embodiment of the present invention may manufacture a scroll with improved formability and improved mechanical properties and surface.

Hereinafter, preferred examples are presented to aid in the understanding of the present invention, but the following examples are only illustrative of the present invention, and the scope of the present invention is not limited to the following examples.

Example

Silicon (Si) 8 to 16 wt%, copper (Cu) 1 to 7 wt%, magnesium (Mg) 0.1 to 2 wt%, manganese (Mn) 0.05 to 2 wt%, nickel (Ni) 0.01 to 3 wt% and An aluminum alloy in which the individual content of inevitable impurities does not exceed 0.05% by weight and the remainder is aluminum was developed and used to manufacture scrolls.

Si Cu Mg Mn Ni Sr P Sample 1 11.5 4 One 0.5 2 0.5 - Sample 2 9 One 0.5 - 1.5 0.5 - Sample 3 15 5 1.5 One - - 0.05

Table 1 is a composition of an aluminum alloy designed within the allowable content range for each element.

By dissolving the designed alloy, a thin rod with a diameter of 100 mm was produced by a gas-pressurized vertical continuous process.

The produced small diameter rods were homogenized for 12 hours at a temperature of 490 °C to remove macrosegregation.

The homogenized thin rod was surface-cut to a diameter of 96 mm and cut to have an appropriate weight to prepare a forged slug.

The cut forged slug was coated with lubrication on the surface through a lubrication coating process.

The forged slug coated with lubrication was heated to 400° C. and then mounted on a scroll forging device according to an embodiment of the present invention.

The upper mold including a liquid lubricant supply line equipped with a space for receiving and storing liquid lubricant is pressed to fill the forming space of the scroll by flowing metal in the pressing direction and the reverse direction, and at the same time, the scroll formed in the lower mold The molding was completed by filling the space of the lower shape.

The molded scroll was heated to 490° C., cooled with water, and maintained at 185° C. for 6 hours to complete the heat treatment.

Experimental example

Tensile strength (MPa) Yield strength (MPa) Hardness (HRB) Sample 1 424 365 83 Sample 2 432 350 82 Sample 3 410 384 84

[Material property evaluation method]

Specimens were prepared according to ASTM D 638 to measure tensile strength, yield strength, and hardness.

According to an embodiment of the present invention, the solution treatment and aging heat treatment were completed to obtain a scroll having a tensile strength of 405 to 435 MPa, a yield strength of 345 to 390 MPa, and a hardness of 80 to 85 HRB.

13 is an optical microscopic microstructure photograph of the produced aluminum alloy structure in a method for manufacturing a scroll according to an embodiment of the present invention.

Referring to FIG. 13, it can be seen that primary Si has been refined.

Therefore, it is possible to manufacture a scroll having high mechanical properties by continuously forging processing by the rear molding forging method.

In addition, by reducing the friction force between the forging slug and the mold in the forging forming step, it is possible to prevent uneven forming of the scroll, suppress the increase in forging pressure, and thus prevent the shortening of the life of the mold.

Simple modifications or changes of the present invention can be easily implemented by those of ordinary skill in the art, and all such modifications or changes can be considered to be included in the scope of the present invention.

1000: scroll forging device
100: base 110: guide hole
120: vertical guide 200: lower mold
210: forming chamber 220: scroll flange forming groove
230: eject hole 240: lower mold core
250: lower mold holder 300: lower eject pin
400: ram 500: holder
600: upper mold 610: through hole
620: liquid lubricant supply line 621: liquid lubricant supply space
622: discharge port 630: lubricant
631: oil film 640: oil hole
650: scroll pin forming groove 651: inclined surface
700: upper eject pin 800: forged slug
810: scroll 811: scroll pin
812: scroll flange

Claims (12)

(a) Silicon (Si): 8 to 16 wt%, Copper (Cu): 1 to 7 wt%, Magnesium (Mg): 0.1 to 2 wt%, Manganese (Mn): 0.05 to 2 wt%, Nickel (Ni ): 0.01 to 3% by weight, and the individual content of the inevitable impurities does not exceed 0.05% by weight and the remaining aluminum alloy is dissolved in a melting step;
(b) vertical continuous casting step of manufacturing a small diameter rod from the molten aluminum alloy;
(c) a homogeneous treatment step of removing macro segregation of the cast fine-gyeongbong;
(d) a surface processing step of processing the surface of the small diameter rod subjected to homogeneous treatment;
(e) manufacturing a forged slug by cutting the surface-processed small diameter rod;
(f) a solid lubrication step of applying a lubricant to the surface of the forged slug;
(g) a heating step of heating the forged slug coated with a lubricant on the surface; And
(h) a scroll manufacturing method comprising the step of forging the heated forged slug by placing it on a lower mold and pressing it with an upper mold having a molding space and a liquid lubricant supply line.
The method of claim 1,
In the melting step, the aluminum alloy further contains 0.1 to 0.5% by weight of strontium (Sr) when the content of silicon (Si) is less than 12% by weight, and 0.01 to 0.1% phosphorus (P) when it exceeds 12% by weight. Scroll manufacturing method, characterized in that it further comprises a weight percent.
The method of claim 1,
The vertical continuous casting step is a scroll manufacturing method, characterized in that the vertical continuous casting of a small diameter rod of 100 mm or less in diameter by a gas pressure casting method in which the molten aluminum alloy is pressurized with an inert gas and supplied to the mold.
The method of claim 1,
After the step of forging by pressing with the upper mold, the scroll is heated to 480 to 510°C and water-cooled, followed by a solution treatment, and then reheated to 180 to 250°C and maintained for 4 to 10 hours. Way.
The method of claim 4,
The scroll manufacturing method, characterized in that the solution treatment and aging heat treatment are completed, the tensile strength 405 ~ 435 MPa, yield strength 345 ~ 390 MPa, hardness 80 ~ 85 HRB.
In a scroll forging apparatus for performing the step of forging the forged slug of claim 1 on a lower mold and pressing it with an upper mold having a forming space and a liquid lubricant supply line,
A base having a guide hole formed in the center and provided with a plurality of vertical guides along the outer circumference;
A lower mold disposed on the base and having a forming chamber in which the heated forged slug is seated, a scroll flange forming groove formed at one side of the forming chamber, and an eject hole communicating with the guide hole formed at a center thereof;
A lower eject pin having one end fastened to the guide hole, moving along the eject hole and pressing the forged slug to raise the formed scroll;
A ram that is fastened to the vertical guide and moves vertically;
A holder mounted under the ram and having a circular ring shape;
Supported by the holder, a through hole is formed inside, a liquid lubrication supply space is provided at one side of the through hole, and a scroll pin forming groove is formed at one end of the through hole to pressurize the forged slug to allow the metal flowing into the inside. An upper mold that is introduced to form a scroll pin; And
It is mounted to be vertically movable in the through hole, and includes an upper ejection pin for pressing and discharging the scroll on which the scroll pin is formed,
The through hole is provided with a liquid lubricant supply line on one side of the upper portion, and the liquid lubricant supply line continuously supplies lubricant between the upper eject pin and the through hole when the upper eject pin moves vertically, and supplies the liquid lubricant In the line, when lubricant is injected into the through hole, the lubricant forms an oil film on the inner surface of the through hole, and the upper eject pin descends to discharge the scroll on which the scroll pin is formed, an oil film is formed on the inner surface of the scroll pin forming groove. Scroll forging device, characterized in that to form.
The method of claim 6,
Scroll forging apparatus, characterized in that the scroll pin forming groove is formed in a circular or spiral shape.
delete The method of claim 6,
The liquid lubricating oil supply line is connected to a lubricating supply device formed by a lubricating pump and an injector device outside the upper mold, and has a lubricating hole through which lubricating oil can be injected into the liquid lubricating supply space at one side of the through hole. Scroll forging device.
delete delete The method of claim 6,
Scroll forging apparatus, characterized in that the inner surface of the scroll pin forming groove is provided with an inclined surface of more than 0 ° and 5 ° or less in an outward direction from a vertical center.

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