SU1473901A1 - Method of centrifugal casting ,particularly, of thick-wall hollow articles - Google Patents

Abstract

The invention relates to foundry, namely centrifugal casting, and is intended for the manufacture of predominantly thick-walled hollow castings from alloys of ferrous and non-ferrous metals. The purpose of the invention is to improve the quality of castings by increasing the density and preventing segregation along the wall thickness. The method involves pouring the liquid metal into the rotating mold 1, the effect of a cooled rotating roller 2 on the free surface of the casting 3 involved in the rotation of the liquid metal with constant contact of the roller 2 in the process of increasing the thickness of the casting 3. The pouring funnel 4 is placed on the end surface of the form 1. Constant The contact of the surface of the roll 2 with the free surface of the metal of the casting 3 is accomplished by moving the roll 2 radially to the axis of rotation of the form 1.1 Cp. f., 3 sludge.

Description

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The invention relates to foundry, namely centrifugal casting, and is intended for the manufacture of predominantly thick-walled hollow castings from alloys of ferrous and non-ferrous metals.

The purpose of the invention is to improve the quality of the flap by increasing the density and preventing segregation along the wall thickness.

FIG. Figure 1 shows the mold for 10 along the wall thickness of the casting 3, due to the centrifugal casting, inside of which is placed optimal conditions for the cooled rotating roll; in fig. 2 shows section A-A in FIG. one; on

forming high-quality casting 3 by increasing the density and preventing segregation along the wall thickness.

By varying the speed of rotation of the mold 1 and pouring, the movement of the roll 2 along the radius R to the axis of rotation and other technological factors, it is possible to control the duration of the interaction of the roll 2 with the melt involved in the rotation, i.e. control

FIG. 3 shows the node I in FIG. 2 (zone of contact of the forming roll with the free surface of the liquid metal involved in the rotation).

Form 1 for centrifugal casting has an axis of rotation from -O. Inside the mold 1 there is a cooled roll 2, the axis of rotation of which is O -) - changes the position 20 of the structure formation process. in the process of forming the casting 3. The filling funnel 4 is placed from the end surface of the form 1.

The method involves a series of actions. Before pouring the molten metal into form 1, roller 2, having a radius of gV, is set at a distance b from the inner wall of form 1. The specified distance determines the thickness of the first melt layer involved in the rotation and depends on the rotation speed 25

Claims (2)

Claim 1. Centrifugal casting method predominantly of thick-walled hollow castings, which involves pouring liquid metal into a rotating form, exposing it to a cooled rotating roller, characterized in that, in order to improve the quality of castings by increasing the density and preventing segregation of the mold 1 (1 f), the radius of its internal -DQ tire to the wall, the effect of the roller on the surface R, the casting speed, the properties of the alloy, the temperature of the cast metal. It was established experimentally that for cast iron, the value of 6 is 0.5-3.0 mm, and for other alloys, provided the correct pouring temperature is chosen, the thickness of the first melt layer involved in the rotation remains within the same limits. As soon as the first portion of the melt is involved in the rotation of the mold 1, it is injected onto the free surface of the liquid metal involved in the rotation, ensuring that the roller makes constant contact with the liquid metal in the process of increasing the thickness of the casting. 2. A method according to claim 1, characterized in that the constant contact of the roll surface with the free surface of the metal of the casting is carried out by moving the roll radially to the axis of rotation of the mold. 1473901 The surface of the forming casting 3 comes into contact with a roller 2 rotating at a speed of rolling, rolling it around. At constant contact with the casting 3 increasing in thickness, the roll 2 is displaced along the radius R to the axis of rotation of the mold 1 to the distance Cb-O |. The interaction of the cooled roll 2 with the liquid metal accelerates the cooling of each layer, reduces the temperature gradient through the wall thickness of the casting 3, which ensures optimum conditions forming high-quality casting 3 by increasing the density and preventing segregation along the wall thickness. By varying the speed of rotation of the mold 1 and pouring, the movement of the roll 2 along the radius R to the axis of rotation and other technological factors, it is possible to control the duration of the interaction of the roll 2 with the melt involved in the rotation, i.e. control process of structure formation. process of structure formation. Claim 1. Centrifugal casting method predominantly of thick-walled hollow castings, which involves pouring liquid metal into a rotating mold, exposing it to a cooled rotating roller, characterized in that, in order to improve the quality of castings by increasing the density and preventing the wall from segregating through thickness, to implement they are on the free surface of the liquid metal involved in the rotation with the constant contact of the roll with the liquid metal in the process of increasing the thickness of the casting. 2. A method according to claim 1, characterized in that the constant contact of the roll surface with the free surface of the metal of the casting is carried out by moving the roll radially to the axis of rotation of the mold. Fi.Z