RU2357832C2 - Gate system - Google Patents

Abstract

FIELD: mechanics.

SUBSTANCE: invention relates to foundry engineering. The system consists of a down gate, horizontal ingate, slotted feeder and one or several head skimming gates connected to the ingate and slotted feeder. In periphery of each head skimming gate, there is a metal plate in front of the slotted feeder inlet. It is installed perpendicular or at an angle to the head skimming gate. The plate has a melting temperature, which is not more than the temperature of the melt being poured. The plate thickness is selected upon a condition that plate integrity is preserved until the moment of head is filled up with metal.

EFFECT: improved quality of mold and reduced number of defects by slag and sand inclusions.

2 dwg, 1 ex

Description

The invention relates to the field of foundry, in particular to the casting of steel parts in single sand-clay forms. It can be used in various fields of technology in the manufacture of large-sized thin-walled steel castings, in particular, in car building for the casting of load-bearing parts of freight cars.

A sprue system containing a riser, a slag trap and a feeder is known, in which the end portion of the feeder is made with narrowing, and in its middle part there is a throttle with a T-section (SU 16750245, B22C 9/08, Bulletin No. 33, 1991). The disadvantage of this device is that the clamping of the cross section of the feeder is performed directly from the mold material, therefore, for massive thin-walled steel castings with a long period of hydrodynamic influence of the melt, the gating system erodes with the formation of non-metallic inclusions or sand shells emerging on the surface of the castings.

The closest analogue of the claimed technical solution is the gating system containing a riser, a horizontal gating channel and a feeder (SU 1210957, B22C 9/08, 02/15/1986), but it also does not provide sufficient removal of slag and sand inclusions in steel castings made in single sand and clay forms.

The aim of the invention is to improve the quality of large-sized thin-walled steel castings and reduce rejects on slag and sand inclusions.

This goal is achieved by the fact that the gating system comprising a riser, a horizontal gating channel and a slot feeder is equipped with one or more profit slag traps connected to the gating channel and a slot feeder, while on the periphery of each profit slag trap before entering the slot feeder perpendicularly or at an angle to it, a metal plate is installed having a melting point not higher than the temperature of the molten melt and blocking the entrance to the slot feeder, while the metal plate Astin has a thickness selected from the condition of maintaining its integrity by the time the profit is filled with metal.

Distinctive features of the developed technical solutions are:

- the presence of a slag trap connected to the gate channel and the slot feeder;

the execution on the periphery of the profit-slag trap before entering the slot feeder perpendicularly or at an angle to it a metal plate having a melting point not higher than the temperature of the molten melt and blocking the entrance to the slot feeder;

- the thickness of the metal plate, selected from the condition of maintaining its integrity by the time the profit is filled with metal.

The significance of the distinguishing features is confirmed by the following.

The presence of a slag trap between the gate channel and the entrance to the slot feeder is necessary to ensure ascent when it is filled with a melt of slag and sand inclusions before the metal enters the feeder. Moreover, to prevent the latter from entering the mold cavity during the initial pouring period, the entrance to the feeder is blocked by installing a metal plate having a melting temperature not higher than the temperature of the molten melt. To counter the hydrodynamic pressure of the melt flow, the thickness of the metal plate is selected from the condition of maintaining its integrity by the time the profit-slag trap is filled with metal.

Concrete example

Figure 1 shows a vertical section aa located behind the riser section of the gating system depicted in figure 2, intended for casting the side frame of the carriage in a single sand-clay form, consisting of a horizontal gating channel 1, two side profits-slag traps 2 , on the periphery of which there are steel plates 3 1 mm thick overlapping the entrances to the vertical slot feeders 4 with a cross section of 9 × 70 mm adjacent to the cavity of the mold 5. The thickness of the metal plates is selected taking into account and the hydrodynamic effects of the melt to fill the profits, slag traps, which is necessary to ensure the closure of the gating system during the pouring process.

This gating system in the conditions of mass production of steel car castings provides a significant reduction in rejects on sand blockages and slag inclusions.

Claims (1)

A gating system comprising a riser, a horizontal gating channel and a slot feeder, characterized in that it is provided with one or more gutter profits connected to the gating channel and a gutter feeder, at the same time on the periphery of each gutter profit before entering the crevice feeder perpendicularly or below a metal plate having a melting point no higher than the temperature of the molten melt and blocking the entrance to the slot feeder is installed at an angle to it, while the metal plate has Thickness selected from the condition of preserving its integrity at the time of filling the metal profits.

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