RU2557037C2 - Pouring gate system with sump-insert - Google Patents

Abstract

FIELD: metallurgy.

SUBSTANCE: pouring gate system contains pouring basin, riser, sump, slug catcher with feeders, throttle and sump-insert. The sump-insert is made out of rods and is arranged under vertical riser in bottom half-mould. The sump-insert gas U shape and contains central and side parts. In the central part of the sump-insert the sump is made, at both sides of the sump on here internal surfaces of the sump-insert two throttles are installed. The throttles have shape of triangular prisms and act as stress concentrators. Side parts of the sump-insert are part of the slug catcher. The vertical riser is located at centre of the mould above the slug catcher located at both sides of the vertical riser symmetrically to its axis.

EFFECT: easy separation of the pouring gate system to parts on the knockout grate.

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Description

The present invention relates to foundry, and in particular to devices for supplying molten metal, and can be used in the manufacture of gate systems with a sump insert.

Closest to the claimed invention is a sprue-feeding system, consisting of a sprue bowl, a vertical riser, a slag trap located in a horizontal plane, feeders, lateral pouring profit, upper drainage profit, throttle, sump and booster (Sharifyanov F.Sh. and Mamleev R .F. Casting design.Tutorial.Ufa, Ufa State Aviation Technical University, 2002, 205 pp., Fig. 3.6, pp. 125-126).

The disadvantages of the known gate-feeding system are:

- insufficient quality of castings;

- the difficulty of separating the gate-feeding system into parts on a knocked out lattice.

The claimed technical solution is aimed at improving the quality of castings and expanding technological capabilities by facilitating the separation of the gating system into parts on a knockout grate.

The technical result is achieved by the fact that in the sprue system containing the sprue bowl, a vertical riser, with a sump located under it, a slag trap horizontally located in the lower half-mold with feeders and choke perpendicular to it, a vertical riser is placed in the center of the mold above the slag trap located on both the sides of the vertical riser symmetrically to its axis, under the vertical riser in the lower half-mold there is a sump-insert made of a core mixture having a U-shape and consisting of the central and lateral parts, while in the central part of the sump insert there is a sump, and on both sides of the sump on the three internal surfaces of the sump insert there are two chokes, which look like triangular prisms, and at the same time function as voltage concentrators, the sides of the sump inserts are part of a slag trap.

Figure 1 shows the gating system with a sump insert, General view.

The gating system contains a slag trap 1 horizontally located in the lower half-mold 2. In the center of the mold above the slag trap 1, a vertical riser 3 with a sprue bowl 4 is located symmetrically to its axis. A sump insert is located under the vertical riser 3 in the lower half-mold 2. On both sides of the riser 3, perpendicular to the slag trap 1, feeders are allotted.

The sprue bowl 4 is a funnel and serves to receive molten metal jets from the bucket.

The vertical riser 3 is a vertical cylindrical channel from which metal flows to other elements of the gate system.

Slag trap 1 is a trapezoidal channel horizontally located in the lower half-mold 2. Feeders are a channel for supplying molten metal directly into the mold cavity.

The sump insert is U-shaped and consists of a central part 5 and side parts 6.

In the central part 5 of the sump insert, a sump is made, which is a recess under the vertical riser 3. The sump is designed to reduce the erosive effect on the shape of the falling stream of liquid metal at the beginning of filling the vertical riser 3.

On both sides of the sump on the three internal surfaces of the sump insert (side walls and bottom) there are two chokes 7 having the form of triangular prisms. The throttles 7 are local narrowing, designed to "lock" the vertical riser 3 and thereby maintain it in a filled state when pouring molds, as well as to maintain a certain level of alloy in the casting bowl 4.

Thus, the presence of chokes 7 reduces the likelihood of such a defect on castings as slag blockage, since slag inclusions do not get into the mold, but accumulate on the surface of the alloy in the casting bowl 4.

Simultaneously with the function of controlling the flow rate of the alloy into the mold (holding the design pressure in the vertical riser 3), the inductors 7 perform the function of stress concentrators, being a zone of deformation and fracture. This allows the gating system, passing after crystallization along the knocked-out lattice, to be guaranteed to be divided into three parts.

The lateral parts 6 of the sump insert are part of a slag trap 1 located in the lower half-mold 2 on both sides of the vertical riser 3 symmetrically to its axis.

The sump insert is made of a core mixture, which has higher strength characteristics than the molding mixture, from which other parts of the gate system are made. This allows the use of a sump insert to prevent erosion of the mold surface in the region of the sump and chokes 7, reducing the likelihood of defects on castings such as earthen blockage and sand shells.

Gating system with a sump insert works as follows.

The alloy from the casting ladle is poured into the casting bowl 4, then, through the vertical riser 3, the alloy enters the central part 5 of the sump insert. Passing through the chokes 7, the level of the alloy increases due to a decrease in the bore in the zone of the chokes 7. Then the alloy fills the remaining elements of the gate system and the mold cavity. After filling the entire mold cavity with alloy, a crystallization process takes place. After crystallization is completed, the castings are knocked out from the gating system on a knockout grate. Passing along the knockout grate, the gating system, collapsing in the zone of stress concentrators of the sump insert, is divided into at least three parts - a riser with a bowl, the left branch of the gate system, and the right branch of the gate system. Separation of the sprue system reduces the mass of the falling parts, softening the impact force when passing through the tiers of the knocked-out lattice, which in turn provides a reduction in the level of casting defects such as warpage, chipping and nick.

Thus, the gating system with a sump insert creates optimal conditions for obtaining high-quality castings.

Using the proposed technical solution allows you to:

1. Improve the quality of castings, reducing the likelihood of the following defects:

- slag blockage - due to the presence of throttles that guarantee guaranteed to maintain a certain level of alloy in the casting bowl, as a result of which slag inclusions do not fall into the mold, but accumulate on the surface of the alloy in the casting bowl;

- earthen blockage and sand shells - due to the elimination of erosion of the mold surface in the area of the sump and chokes, due to the fact that the sump insert is made of a core mixture having higher strength characteristics than the molding mixture from which other parts of the gate system are made;

- warping, chipping and nick due to the guaranteed separation of the sprue system, which entails a reduction in the mass of the parts of the sprue system falling on the knockout grate and softens the impact force when passing through the knockout grate.

2. To expand technological capabilities by facilitating the separation of the elements of the gating system into parts when passing through the knockout grate, due to the presence of chokes, which simultaneously serve as stress concentrators.

Claims (1)

The gating system comprising a gating cup, a vertical riser, a sump, a slag trap horizontally located in the lower half-mold, with feeders and a choke, characterized in that it is equipped with a sump-insert made of a core mixture placed under the vertical riser in the lower half-mold having a U-shape and consisting of a central and lateral parts, wherein the sump is made in the central part of the sump insert, and on both sides of the sump on the three inner surfaces of the sump insert there are chokes in the form of triangles x prisms that act as voltage concentrators, and the lateral parts of the sump insert are parts of the slag trap, with the vertical riser placed in the center of the mold, and the slag trap located on both sides of the vertical riser symmetrically about its axis.

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