RU1806035C - Method of pulse compaction of moulding mixture - Google Patents

Abstract

Using; in foundry, in particular in methods for making foundry molds. SUMMARY OF THE INVENTION: the proposed method is implemented as follows: the air flow exerts a pulsed effect on the mixture, which is vertical and laterally through the holes in the walls of the filling frame. The lateral effect is carried out at an angle of 10-90 °; to vertical impulse action. 1 s P. f-ly, 2 ill.

Description

The invention relates to foundry, in particular, to methods for manufacturing foundry molds,

 The purpose of the invention is to reduce air consumption and improve mold quality due to better adhesion of the lump mixture to the walls of the flask.

In FIG. 1 shows a diagram of an implementation of the claimed method; in FIG. 2 - moment, form sealing.

The filling frame 1 and the flask 2 are mounted on the model plate 3c with models and filled with the mixture 4. Then, using the mechanism 5, they are pressed against the pulse head 6, consisting of a receiver 7 and a transition chamber 8, separated by an air valve 9, and the filling frame is inside the transition chamber, and the flask - outside (due to the different thicknesses of the adjacent flanges of the flask and frame). The walls of the frame are provided with holes 10. The receiver 7 is filled with compressed air. Flo Achieving Necessary

the operating pressure, the valve 9 opens and air from the receiver rushes into the chamber 8 and exerts a pulsed effect on the mixture, which is vertical and laterally through the openings in the frame walls. Thus, a pressure wave acts on the free surface of the mixture in the frame and additionally on the side surface of the coma through the holes. The mixture in the frame is subjected to a similar action to a shotgun in the sleeve of a sandblasting machine.

A packet of mixture is formed in the frame, which is pressed into the flask under the influence of vertical pressure. In this case, there is no friction of the mixture packet against the walls of the frame, which increases the speed of movement of the mixture and thereby increases the inertia forces under which the mixture is compacted during pulsed molding.

Due to the presence of holes in the walls of the frame, some of the air penetrates along the wall of the flask, since the mixture in the frames

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ke moves away from the walls. Thus, an air gap is formed in the flask, similar to the prototype. .

All the positive phenomena noted in the prototype method are retained by eliminating the area of the re-compacted jumper between the flask and the model and the under-zone below it. The air gap is smaller than when using the known method, less time is applied, and the packet of the mixture strikes the model with great force and spreads in all directions during compaction (the principle of sand-blasted molding), which ensures good adhesion of the coma to the flask. which eliminates the risk of mold breaking during transportation and pouring.

The mold quality is higher, the air consumption is lower, the sealing cycle is also shorter (since air purging is not needed), vents, compressor and other additional devices are not needed. The adhesion force of the coma of the mixture to the flask can be adjusted by changing the ratio of the fraction of air going to the additional effect on the mixture and on the creation of the interlayer. To do this, it is necessary to change the angle (impact) of the outflow of air jets through-, in the walls of the frame relative to the vertical component in the range of 10-90 °

It was found that if a is 10 °, then the additional air flow actually moves in the direction of the main one and will not have an additional effect on the molding mixture during compaction. If a is 90 °, then the mixture will be ejected upward from the filling frame. In this case, the additional air flow is directed towards the main one and the efficiency of the pulse action is reduced.

When using the claimed method, better adhesion of the lump of the sand to the flask is ensured, which prevents the destruction of the mold. The hardness and density of the mold are 87-89 units of 1.66-1.68 g / cm3, respectively.

FORMULA AND ZOBRETIN

Claims (2)

1. The method of pulse compaction of the moldable mixture, comprising filling the flask and the filling frame with the mixture and sealing it with a short-term action of a pulse of compressed air, such as the fact that the mixture in the filling frame is impacted from the sides by a pulse compressed air simultaneously with the main impact. 2. The method according to claim 1, characterized in that the additional effect is at an angle of 10-90 ° to the main pulse effect. 0 5 0 5