The process flow of casting production

The process flow of casting production:

Casting production is a complex multi-step combined process that includes the following main steps:

1) Preparation of production processes, formulating production process plans and documents based on the drawings of the parts to be produced, production batch, and delivery deadlines, and drawing casting process diagrams;

2) Production preparation, including the preparation of materials for melting, materials and patterns for molding and core making, as well as process equipment such as core boxes and sand boxes;

3) Molding and core making;

4) Melting and pouring;

5) Sand falling cleaning and inspection of castings, among other main processes.

The principle of forming

Casting production involves heating and melting metal to achieve fluidity, which is then poured into a mold cavity of a specific shape. Under the influence of gravity or external forces (such as pressure, centrifugal force, electromagnetic force, etc.), the cavity is filled, and the metal cools and solidifies into a casting (or part).

Castings are generally processed into parts through cutting. However, many castings can meet the design precision and surface roughness requirements of parts without the need for cutting, and can be used directly as parts.

The properties and composition of molding sand

1. Properties of molding sand

The main performance requirements for molding sand (including core sand) include strength, permeability, refractoriness, collapsibility, fluidity, compactness, and disintegration.

2. Composition of molding sand

Molding sand is composed of base sand, binders, and additives. The base sand for casting should have low clay content, uniform particle size, and be in the shape of round or polygonal sea sand, river sand, or mountain sand. The binders used for casting include clay (ordinary clay and bentonite), water glass sand, resin, fatty oils, and vegetable oils, referred to as clay sand, water glass sand, resin sand, fatty oil sand, and vegetable oil sand, respectively. To further enhance certain properties of the molding (core) sand, various additives such as coal powder, sawdust, and pulp are often incorporated into the molding (core) sand structure.

The characteristics of the casting process are as follows:

1) Castings are not limited by the type of metal material, size, or weight. The materials for castings can include various types of cast iron, cast steel, aluminum alloys, copper alloys, magnesium alloys, titanium alloys, zinc alloys, and various special alloy materials; castings can range from a few grams to hundreds of tons; the wall thickness of castings can vary from approximately 0.5 millimeters to 1 meter; the length of castings can range from a few millimeters to several meters.

2) Casting can produce blanks of various complex shapes, making it particularly suitable for producing parts with intricate internal cavities, such as various housings, cylinder blocks, blades, and impellers.

3) The shape and size of castings can closely match the parts, which saves metal materials and reduces machining time.

4) The raw materials used for castings are widely sourced, and the cost of castings is low.

5) The casting process is flexible and has a high production rate, allowing for both manual and mechanized production.