RU2703078C1 - Method of making castings in vacuum-film molds on conveyor and device for its implementation - Google Patents

Abstract

FIELD: technological processes.SUBSTANCE: invention relates to the foundry. Molds (1) are made on conveyor (2) from loose molding material by vacuum-film molding. Prior to metal pouring between casting mold (N) and pouring mold (N-1) supplied under casting, movable protective element (4) is placed. Movable protective element is made in the form of sheet from heat-resistant material and fixed on filling device (3).EFFECT: higher quality and prevention of rejects of casts.9 cl, 1 dwg

Description

The invention relates to foundry, namely, to the manufacture of castings in foundry molds obtained by the method of vacuum-film molding, located during pouring in close proximity to each other, in particular, on the conveyor.

A known method of manufacturing castings in vacuum-film forms on a conveyor, including applying a synthetic film to a model and a model plate, swiveling the flasks between the intermediate plates into the conveyor, supplying the device with a conveyor box with movable drive bottoms, filling the flask with sand and evacuating the flasks assembly of half-molds into a mold, feeding under pouring from a casting ladle and removal of castings after cooling by a separate conveyor (see RU 2020025 C1, publ. 30.09.1994).

It is known to manufacture castings in vacuum-film molds on a conveyor, adopted as the closest analogue, including assembling casting molds by joining and fastening half-molds obtained by vacuum-film molding, placing molds on a conveyor by installing them on a roller table with end-to-end rollers with a previously installed casting mold, feeding casting molds for pouring with molten metal, casting casting molds from a pouring ladle, cooling castings in vacuum forms (see RU 2044592 C1, publ. l. September 27, 1995).

The technical problem inherent in the known technical solutions is the lack of technological operations for protection during pouring from splashing molten metal onto the surface of the mold waiting to be cast. Due to the effects of hot spray, the mold overlaying film is easily destroyed, causing depressurization and local collapses, which can degrade the quality of the casting.

The technical result of the invention is to improve the quality of castings made in vacuum-film forms on the conveyor.

The specified technical result is achieved by the fact that in the method of manufacturing castings in casting molds on a conveyor, which includes assembling casting molds by joining half-molds obtained by vacuum-film molding, installing casting molds on a conveyor, feeding casting molds for pouring with molten metal, casting casting molds from the casting ladle, cooling and removing castings, in contrast to the closest analogue, for the duration of casting of each mold between the mold located under the casting ladle, and adjacent movable mold located at the standby position of the fill, place a movable protective element.

In a preferred embodiment of the invention, the movable security element is lifted during the filing of molds for pouring.

In particular embodiments of the invention, a movable security element is placed between the molds by its rotational movement around the axis of the hinge.

In particular embodiments of the invention, a movable protective element is placed between the molds by reciprocating along guides.

In particular cases of implementing the invention, before applying the casting mold for casting, a layer of sand is applied to the surface of the casting mold located at the standby position of casting.

Placing a movable protective element between pouring and waiting to be filled with casting molds during casting allows you to reliably protect the synthetic film deposited on the surface of the casting mold, which is waiting to be filled, from splashes of molten metal from the pouring ladle, as well as from the spouts and riser of the casting mold. Thus, depressurization of each pending casting mold is excluded, which ensures an increase in the quality of castings produced.

The application of a sand layer as a protective refractory layer on the surface of the pending casting mold provides an additional degree of protection for the synthetic film.

During the filing of each casting mold for pouring, upon completion of pouring the next casting mold, the movable protective element is lifted in order to freely move the casting molds relative to each other on the conveyor and casting device.

Known equipment for the manufacture of castings in vacuum-film molds on a conveyor, comprising a roller conveyor and casting molds mounted on rollers end-to-end to each other, assembled from half-molds obtained by vacuum-film molding, while the side walls of the flasks are removable for installation instead of them with a common a gas-permeable wall, which ensures the expansion of rarefaction in all forms along a common collector channel (see RU 2044592 C1, publ. 09/27/1995).

Known automatic casting line for the production of castings by vacuum molding, adopted as the closest analogue, containing located in the technological sequence of the device for vacuum-film molding, feeding molds for pouring molten metal, casting molds with metal, cooling and removing castings associated with the transport system with bogies and fliers (see. and. S. USSR No. 975202, publ. 23.11.82).

The technical problem inherent in the known technical solutions is the lack of structural elements that protect the surface of the mold awaiting casting from splashing molten metal during the casting process. The synthetic film covering the mold is destroyed under the influence of metal sprays, partial depressurization of the mold occurs, which leads to a deterioration in the quality of the casting.

The technical result of the invention is to improve the quality of castings made in vacuum-film forms on the conveyor.

The specified technical result is achieved by the fact that in the device for manufacturing castings in vacuum-film casting molds on a conveyor containing the devices for vacuum-film molding located in the technological sequence, a conveyor for feeding casting molds for metal casting, a casting device with a casting bucket, cooling devices and knocking out castings, in contrast to the closest analogue, a movable protective element is fixed on the filling device to place it between the mold Proposition under the pouring ladle, and related mold located on the casting standby position.

In a preferred embodiment, the movable security element is in the form of a flat sheet of heat-resistant material.

In particular forms of implementation, the movable protective element is fixed to the filling device by a swivel with the possibility of its rotational movement around the axis of the hinge.

In private forms of implementation, the movable protective element is fixed on the filling device in the guides with the possibility of its reciprocating movement along the guides.

Fastening the movable protective element on the filling device to place it between the pouring and the pouring molds waiting to be cast allows protecting from splashes coming from the spouts and the riser of the casting mold on the surface from the counter of the waiting casting of the adjacent mold. This ensures the safety and integrity of the film covering the casting mold located at the standby position of the casting, its depressurization and local collapses are excluded, casting marriage is reduced.

The implementation of the movable protective element in the form of a sheet of heat-resistant material provides reliable protection against metal splashes through a simple low-cost design solution.

The invention is illustrated in the diagram.

Casting molds 1 with cups (or funnels) 1.1 for feeding molten molten metal during pouring are mounted on a conveyor 2, which moves the casting molds 1 relative to the casting device 3. There is also a possible embodiment of the invention in which the casting device 3 moves over the casting molds 1. On casting device 3 has a locking bucket 3.1.

To the lower part of the casting device 3 is attached a movable protective element 4, made in the form of a sheet of heat-resistant material, for example, of heat-resistant steel. The fastening of the movable protective element 4 can be carried out by a swivel joint 5. In this design, a cable 6 and a system of counterweights 7 are provided, which can be conveniently placed on the side of the operator's cab 8 of the filling device 3. A form of the invention is also possible in which the movable protective element 4 is fixed on the filling device 3 in the guides for reciprocating movement of the movable protective element 4 according to the principle of the gate valve.

In order to prevent metal splashes from falling onto the surface of the mold covered with a synthetic film, the movable protective element 4 is made not less than the width of the molds 1. In this case, the lower edge of the movable protective element 4 in a vertical position should be located close to the level of the surfaces of the mold 1 not less than 10 mm, in such a way as to ensure unhindered lifting of the protective element after completion of casting.

The proposed invention works as follows.

A synthetic film is applied to the casting model. Install the flask on the model plate, pour loose molding material into the flask - sand. The half-mold is sealed on the counterattack side by applying a cover film, after which evacuation is carried out. Finished half-molds are assembled into molds 1. The molds 1 are placed on the conveyor 2.

To provide more reliable protection of the mold from splashes of molten metal, an operation known from the prior art for applying sand to the surface of a mold awaiting filling on a conveyor can additionally be performed.

Then the casting molds 1 are fed under the fill by moving the casting device 3 above the casting molds 1, or by moving the casting molds 1 on the conveyor 2 under the casting device 3.

If the casting mold 1 fed for pouring is located in the “Form N” operating position, in which the cup 1.1 is located under the stopper bucket 3.1, the relative movement of the casting molds 1 and the casting device 3 is stopped. Before the start of the casting process, the movable protective element 4 is placed between the casting mold 1 in the operating position "Form N" and the casting mold 1 in the standby position of the casting "Form N-1". To do this, using a cable 6 and a system of counterweights 7, the movable protective element 4 is rotated around the axis of the hinge 5 and set in a vertical position.

Next, fill the mold with 1 jet of molten metal coming from the lock bucket 3.1. In the process of pouring metal into the mold and as it is filled, sparks and splashes of metal flying from the jet flowing out of the lock bucket 3.1, as well as from the spouts and riser of the cast mold 1, fall on the movable protective element 4, which prevents them from falling to the surface of the mold 1 in the standby position of casting "Form N-1". Thus, the synthetic film covering the mold 1 remains intact, which helps to improve the quality of castings.

At the end of the casting process, the next casting mold 1 is fed for casting. The metal-casting mold 1 moves from the operating position “Form N” to the position “Form N + 1”. For unimpeded mutual movement of the molds 1 on the conveyor 2 and the casting device 3 in the process of alternately pouring molds and other operations associated with changing the location of the molds and the casting device, the movable protective element 4 is lifted while the molds are being cast for casting.

Claims (9)

1. A method of manufacturing castings in vacuum-film molds on a conveyor, including assembling molds by joining half-molds obtained by vacuum-film molding, installing molds on a conveyor, feeding molds for pouring with molten metal, casting molds from a casting ladle, cooling and removal of castings, characterized in that before the start of casting, a movable protective element is placed between each casting mold submitted for casting and the casting mold awaiting casting for the time of casting. 2. The method according to p. 1, characterized in that the movable protective element is made in the form of a sheet of heat-resistant material. 3. The method according to p. 1, characterized in that the movable protective element is fixed on the filling device by a swivel joint and placed between the molds by its rotational movement around the axis of the hinge. 4. The method according to p. 1, characterized in that the movable protective element is fixed on the casting device in the guides and placed between the molds by its reciprocating movement along the guides. 5. The method according to p. 1, characterized in that at the time of filing the molds for pouring, the movable protective element is lifted. 6. A device for the manufacture of castings in vacuum-film molds on a conveyor, comprising devices for vacuum-film molding located in the technological sequence, a conveyor for feeding casting molds for metal casting, a casting device with a casting bucket, devices for cooling and removing castings, characterized in that a movable protective element is fixed on the casting device, made with the possibility of its placement between the casting mold located under the casting ladle and the adjacent casting a form located at the standby position of the fill. 7. The device according to p. 6, characterized in that the movable protective element is made in the form of a flat sheet of heat-resistant material. 8. The device according to p. 6, characterized in that the movable protective element is fixed to the filling device by a swivel with the possibility of its rotational movement around the axis of the hinge. 9. The device according to p. 6, characterized in that the movable protective element is mounted on the filling device in the guides with the possibility of its reciprocating movement along the guides.

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