Apparatus for forming metal castings and method for forming metal casting performed by the apparatus
Inactive Publication Date: 2005-01-06
BBS RIVA
View PDF10 Cites 0 Cited by
- Summary
- Abstract
- Description
- Claims
- Application Information
AI Technical Summary
Benefits of technology
[0015] The aim of the present invention is to solve or substantially reduce the problems of known types of apparatus for forming metal castings.
Problems solved by technology
However, in practice, known casting techniques are not always suitable to ensure the formation of castings that are free from structural defects, for example internal tensions and microporosities, especially in the case of the formation of castings having a complex shape, such as wheels of road vehicles made of light alloy and the like.
In particular, for the low-pressure casting technique the problems are linked, most of all, to poor feeding of the cavity of the mold, especially in the case of castings that have a complex geometry, which generates porosities that can be detected by X-rays as a consequence of the turbulent motions of the metal and of overheating.
This problem gradually increases, since during production the level of the metal inside the furnace decreases, the path followed by the aluminum during filling increases, and accordingly the exposed surface inside the riser tube increases, generating a greater quantity of films of solidified metal and oxides.
Films and oxides are of course entrained by the metal into the mold, forming a non-uniform alloy and detracting from the final quality of the provided casting.
Moreover, the low-pressure casting process is a substantially discontinuous process, since it entails downtimes in the production step due to the time required to fill the riser tube and to the steps for filling said furnace.
In particular, the problems linked to the furnace are due substantially to the holding times for filling it and to the variation of the internal pressure during said filling.
Moreover, it is currently difficult to control the quantity of metal that is injected into the cavity of the mold.
Method used
the structure of the environmentally friendly knitted fabric provided by the present invention; figure 2 Flow chart of the yarn wrapping machine for environmentally friendly knitted fabrics and storage devices; image 3 Is the parameter map of the yarn covering machine
View moreImage
Smart Image Click on the blue labels to locate them in the text.
Smart ImageViewing Examples
Examples
Experimental program
Comparison scheme
Effect test
Embodiment Construction
[0040] With reference to the figures, an apparatus for forming metal castings, particularly with hydraulic connection between the holding furnace and the mold, according to the invention, is generally designated by the reference numeral 10.
[0041] The apparatus 10 comprises a hydraulic connection between a holding furnace 11, which contains the molten metal ready for forming, and a mold 14, which in turn comprises a duct 36 for connecting the holding furnace 11 to one or more inlets 12 for introducing the metal into a the cavity 13 of the mold 14, said one or more inlets 12 being arranged, in this case, under said mold 14, and pumping means 15, which are interposed between portions of said duct 36, for pumping a controlled quantity of metal through one or more inlets 12 into said cavity 13, said means being connected to and controlled by an electronic control unit 16.
[0042] As shown in FIG. 3, in this case there is a slot-like inlet 12, which runs continuously and circumferentially...
the structure of the environmentally friendly knitted fabric provided by the present invention; figure 2 Flow chart of the yarn wrapping machine for environmentally friendly knitted fabrics and storage devices; image 3 Is the parameter map of the yarn covering machine
Login to View More PUM
| Property | Measurement | Unit |
|---|---|---|
| Time | aaaaa | aaaaa |
| Temperature | aaaaa | aaaaa |
| Flow rate | aaaaa | aaaaa |
Login to View More
Abstract
An apparatus for forming metal castings, particularly with hydraulic connection between the holding furnace and the mold and a method performed by the apparatus, the hydraulic connection comprising: at least one duct (36) for connecting the holding furnace (11), which contains the molten metal ready for molding, to one or more inlets (12) for introducing metal into the cavity (13) of a corresponding mold (14); and a piston pump (15), interposed between portions (20, 21) of the duct (36), for pumping a controlled quantity of metal through the one or more inlets into the cavity, the piston pump being connected to an electronic control unit (16).
Description
[0001] The present invention relates to an apparatus for forming metal castings, particularly with hydraulic connection between the holding furnace and the mold and to a method for forming metal castings performed by the apparatus. BACKGROUND OF THE INVENTION [0002] As is known, castings made of metal or light alloys are molded by using pouring processes, such as for example the gravity feeding of the molten metal or alloy into closed molds, and the generation of pressure inside the mold by way of feedheads, which feed the molten casting, increasing the hydrostatic load on the metal or alloy, and prevent the formation of cavities or porosities inside the casting during shrinkage in the solidification step. [0003] Another method for forming castings by pouring metal or alloys is so-called low-pressure casting, which substantially consists in placing a mold over a closed furnace whose cavity is fed through a riser tube connected to the furnace, inside which pressure is applied to the ...
Claims
the structure of the environmentally friendly knitted fabric provided by the present invention; figure 2 Flow chart of the yarn wrapping machine for environmentally friendly knitted fabrics and storage devices; image 3 Is the parameter map of the yarn covering machine
Login to View More Application Information
Patent Timeline
Login to View More IPC IPC(8): B22D17/30B22D35/04B22D37/00B22D39/02
CPCB22D17/30B22D39/023B22D37/00B22D35/04
InventorBAUMGARTNER, HEINRICH GEORG
OwnerBBS RIVA