SU1177044A1 - Injection-casting method - Google Patents

Abstract

CASTING METHOD FOR PRESSING predominantly needle radiators, including applying lubricant to the working surfaces of the mold, locking the mold and filling it with melt under pressure, characterized in that, in order to improve the quality of the castings by uniformly lubricating and removing air from the deep cavities of the press -forms, during the application of the lubricant and filling the mold with melt in the cavity of the mold, create a vacuum by ejection of air.

Description

| iik 4;

eleven

The invention relates to foundry, in particular to injection molding of complex castings, mainly needle radiators.

The purpose of the invention is to increase the cd quality of castings by uniformly applying lubricant and removing air from the deep cavities of the mold.

The essence of the method lies in the fact that in the process of applying lubricant and filling the mold with melt in the deep cavities of the mold, a vacuum is created by ejection of air.

FIG. 1 shows schematically a mold, a section; in fig. 2, section A-A in FIG. one.

The mold contains a stationary half-mold 1 and a mobile half-mold 2, in which the molding cavity 3 is made. The end parts of the castings in which the most likely to form air holes are formed by the rods 4, which have ventilation channels 5 connected to the cavity 6 vacuum openings, which are connected to pneumatic channels 8 through slots 7. In half-molds 1 and 2, throttling valves 9 are installed with openings 10 fully or partially coinciding with openings of channel 8. To move valves 9 to applying lubricant to the half-molds are springs 11. To the other extreme position (full opening of the pneumatic channel), the valves 9 move when the mold is locked by the moving half-mold 2.

The method is carried out as follows.

With an open mold, the pneumatic channels 8 are partially passed over the pneumatic channels 8 partially closed by valves, controlled within wide limits by means of a valve, until a vacuum is created in the cavities of the form 0.0965-0.0985 MPa and the molds 1 and 2 are lubricated.

Due to the ejection of air, a directional flow of lubricant is created, which is uniformly applied to the entire surface.

in the roughness of the half-molds, including on the surface of its deep cavities. After applying the paint, the mold is closed and locked, 5, while the valves 9 abut against the slot of the opposite half-mold and, overcoming the resistance of the springs 11, move to the extreme position at which the holes 10

0 completely coincides with the holes of the pneumatic channels 8. The magnitude of the vacuum is increased 1.5-3.5 times.

Next, melt is fed into the mold. The air displaced from the working cavity and the lubricant combustion products flow through the channels 5 into the cavities 6 of the dilution and from there, through the slots 7, are carried to the pneumatic channels 8. Due to the ventilation of the mold, the filling of the deep cavities with the metal is improved.

Example. Die-cast aluminum radiators with a weight of 2 kg, a diameter of 75 mm and a width of 45 mm are obtained. Radiator needles have a diameter of 4 mm, a length of 20 mm. The mold is lubricated by spraying before it is closed after each

0 fill composition LD. At the same time, air is passed through pneumatic channels 8 with a diameter of 30 mm under pressure, controlled by a valve, until a vacuum of 0.097 MPa is created. This vacuum is applied. |) A uniform layer of lubricant with a thickness of 0.05 mm on both working surfaces of the half-molds that have cavities for the needles of radiators. After applying the grease closes

Q and lock the mold, increase the vacuum to 0.0955 MPa, pour the AL 9 alloy at 710 ° C and press it. After the casting crystallizes, it is removed from the mold 5. Castings are obtained without under-refining, gas porosity and with a smooth surface.

The invention allows to improve the quality of castings, reduce by 20-30%

P otlivsk marriage on non-potash. And air shells. I; / 3 t / / J / I I

FIG. 2 6 I

Claims (1)

METHOD FOR PRESSURE CASTING mainly of needle radiators, including applying lubricant to the working surfaces of the mold, locking the mold and filling with melt under pressure, characterized in that ·, in order to improve the quality of castings by uniformly applying lubricant and removing air from deep cavities of the press -forms, during the period of lubrication and filling the mold with the melt in the cavities of the mold create a vacuum by ejection of air. ~ ON ω 1 1177044