Characteristics and Process Flow of the V-Process Casting Production Line

The essential characteristics and process flow of a V-process casting production line are embodied in the following key points:

1.Sealed flask design

The sand flask is manufactured as a sealed box. The vacuum pipelines (exhaust ports) inside the flask cavity are connected to the atmosphere and linked to the vacuum system through control valves.

2.Heating and forming of the pattern film

A heater is installed on the pattern plate to reheat the dedicated plastic film, improving its plasticity. The film is then applied to the pattern and uniformly vacuum-adsorbed onto the pattern surface by adjustable vacuum suction.

3.Application and drying of anti-sticking coating

An air-free spraying process is used to apply an anti-sand-sticking coating with a thickness of 0.1–0.4 mm onto the film.

Drying is achieved either by preheated air with adjustable directional flow or naturally during casting through the rapid evaporation of the alcohol-based solvent.

4.Sand filling under vacuum

A double-layer sand flask equipped with mesh-type exhaust holes and vacuum valves is placed over the pattern. High-temperature-resistant ordinary dry sand is filled into the flask.

According to the small exhaust holes distributed at the flask bottom and on the half-mold surface, sand compaction is achieved proportionally. If necessary, a small amount of silent vibration may be applied.

The anti-sticking coating is located between the pattern film and the molding sand.

5.Covering film and vacuum connection

A lower-quality film is placed over the half mold. The sand flask is then connected to the vacuum system, after which the pattern is intermittently disconnected from the vacuum system.

6.Pattern withdrawal

The pattern is removed from the mold cavity, while the sand flask remains continuously connected to the vacuum system throughout all conveying operations.

7.Core setting and pouring

Cores are installed, the mold halves are assembled, and molten metal is poured. Shortly after metal solidification, the vacuum system is temporarily disconnected. Vacuum is reapplied during subsequent handling until the final transfer to the shakeout station.

8.Shakeout and sand recovery

After the vacuum is fully released, the cooled mold undergoes simple shakeout (in various sequences). The casting is transferred to a conveyor for cooling, and the sand is recovered and recycled for reuse.

9.Distinct shakeout principle

Multiple operational combinations are possible, such as:

Upper flasks with or without castings

Removing castings before or after sand removal

Removing sand from molds with castings in place or dismantling castings after sand removal

Fundamentally, the shakeout principle of V-process molding differs from that of conventional green sand molding. In the V-process, sand flows out freely by gravity from flasks without traditional shakeout mechanisms. This ensures that the casting is released from the molding material without force.

10.Casting finishing and logistics

The castings then undergo cleaning, packaging, and transportation.