SI24307A - Boring of sand cores from castings - Google Patents

Abstract

When drilling sand cores, a dedicated hollow tool is used, which rotates and moves into the center of the sand core. At the edge of the crushing plate, air flows directly into the crushing site. The air takes off the sand in the direction outside the cast, while the air and sand mixture removes the remainder of the core and cleans the surface during the journey.

Description

Dejan LORBER

Lovrenc na Dravsko polje 122B 2324 Lovrenc na Dravsko polje

ROTATION OF BAKED CASTES FROM CASTINGS

The object of the invention is a technological process of cleaning sand cores from different castings, whether non-ferrous metals and their alloys, or ferrous alloys.

The invention enables the cleaning of cores from hot castings, immediately after casting or casting. completed the curing process. This cannot be done with current technology. The technology enables cleaning of all types of sand cores: Cold box, Hot box, Croning and inorganic binder cores. The biggest advantages are:

- Easy to use kernel cleaning device.

- Cheaper core cleaning device.

- No additional labor required. The operation is performed immediately after casting and at the same job as casting.

- No sand blasting required. There is no core residue on the casting.

- Less castings in the intermediate storage during the casting and core cleaning phase.

- Improved process quality control and control due to rapid result and thus reduced ejection. Castings can be serially controlled and finalize already Λ ¹ hour after casting.

- The process is more environmentally friendly. Cleaning takes place immediately after casting and the breakdown of the binder takes a relatively short time. The sand cools rapidly due to air blowing.

- The sand completely degrades during cleaning. Additional crushing or grinding.

preparation for further use is not required.

- The inner surface of the casting is clean and free of sand on the surface.

No additional sandblasting is required due to core residue.

Previous technological solutions for core cleaning are based on two principles:

1. Vibration: The cast is clamped into a dedicated clamping device and is first hit with pneumatic hammers to crack the core. The vibration of the castings follows. The solution is patented with several patents: FR2850890, US2006272792, FR2901161, EP0326138, EP0325928,

W02004067209, VV02007132101, FR2711931, US4718473,

FR2730436, EP0111461, FR2699840, US4722386, DE2947795, DE3219390, EP0304683, VVO9721523, FR2655895, VVO9213663, US5213150, JP63235063, GB2067938, DE3319312 and is quite problematic because of:

- Castings must be completely cooled before cleaning. This means additional intermediate storage and a delay of further production phases of at least 8 to 16 hours.

- Risk of cracking.

- Risk of injury to the piece due to clamping.

- High maintenance cost of the device as it is self-destructive due to high load.

- Remains of sand remain on the surface of the casting and must be sandblasted.

2. Thermal decomposition: The castings are heated in the oven at 400 ° C for 4 to 6 hours so that the binder (phenolic resins) is thermally decomposed. After thermal decomposition, sand from the castings must be emptied. The solution is patented with several patents: US3989227, VV09730805 and is quite problematic because of:

- Castings are collected prior to thermal decomposition into batches - pallets for optimal operation costs. This results in additional intermediate storage and a delay of further production phases of at least 16 to 24 hours.

- Remains of sand remain on the surface of the casting and must be sandblasted.

- An economically and economically wasteful process.

Description of the process of drilling sand castings from castings:

When drilling sand cores, we use a dedicated hollow tool (2) which, by rotating and moving inside the casting (1), grinds the middle of the sand core (3); pressurized air flows through the holes in the tool (4) and flows through the holes in the direction of the ceramic tile (5) directly to the sand crushing site; the blown air moves the sand away from the casting (7), during the expiration the mixture of air and sand removes the rest of the core and cleans the surface.

Claims (1)

PATENT APPLICATION 1. The technological process of drilling sand cores is characterized by: - that the tool (2) grinds the middle of the sand core (3), - air is allowed to flow through the hollow tool (2) to the sand crushing site (5), - that the air flowing through the holes (5) removes the sand from the crushing site (6) in the direction (7) through the casting (1), - that the mixture of air and sand removes the remainder of the core along the casting walls and cleans the casting walls.