Sand casting
Casting method for producing castings in sand molds. Casting of steel, iron, and the majority of non-ferrous alloys can be achieved through sand molding.
Manufacturing processes of Sand casting
Technical features of Sand casting
1)Suitable for producing blanks with intricate shapes, especially those featuring complex internal cavities;
2)Wide adaptability and low cost;
3)For some materials with poor plasticity, such as cast iron, sand casting is the only forming process for making parts or blanks.
Application of Sand casting
Automobile engine castings including cylinder blocks, cylinder heads, crankshafts, and other parts.
Investment casting
Generally, it refers to making a pattern from a fusible material, covering the surface of the pattern with several layers of refractory material to make a shell, and then Removing the pattern and de-shell to obtain a mold without a parting surface, which can be filled after high-temperature roasting. The casting method of sand casting is often called "lost wax casting".
Manufacturing processes of Investment casting
Technical features of Investment casting
◆Advantage
1)High dimensional accuracy and geometric accuracy;
2)High surface roughness;
3)It is capable of casting complex-shaped components, with no limitation on the casting alloys used.
◆Disadvantage
The process is complicated, resulting in higher production costs.
Application of Investment casting
It is well-suited for manufacturing small parts with intricate shapes, demanding high precision or challenging to process through other means, such as turbine engine blades.
Die casting
High pressure is applied to propel molten metal into a precision metal mold cavity at high velocity, enabling the molten metal to cool and solidify under pressure, resulting in the formation of a casting.
Manufacturing processes of Die casting
Technical features of Die casting
◆Advantage
1)During die-casting, the metal liquid is under high pressure and the flow rate is fast;
2)Good product quality, stable size, and good interchangeability;
3)The production efficiency is high, and the die-casting mold can be used more frequently;
4)This method is suitable for large-scale production and provides significant economic advantages.
◆Disadvantage
1)Castings are prone to fine porosity and shrinkage;
2)Die castings exhibit limited plasticity and are not suitable for operating under impact loads and vibrations.
3)When die-casting high-melting point alloys, the life of the mold is low, which affects the expansion of die-casting production.
Application of Die casting
Die castings were first used in the automobile industry and the instrument industry, and then gradually expanded to various industries, such as agricultural machinery, machine tool industry, electronics industry, defense industry, computer, medical equipment, clocks, cameras, daily hardware, and other industries.
Low-pressure casting
It refers to the method of filling the mold with liquid metal under a lower pressure (0.02-0.06MPa) and crystallizing under pressure to form a casting.
Manufacturing processes of Low-pressure casting
Technical features of Low-pressure casting
1)The pressure and speed during pouring are adjustable, enabling its application to various casting molds (including metal molds, sand molds, etc.), as well as the casting of different alloys and components of various sizes.
2)Bottom injection type filling is adopted, the liquid metal filling is stable without splashing, which can avoid the gas involved and the erosion of the mold wall and core, and improve the qualified rate of castings;
3)During the casting process, the application of pressure leads to solidification, resulting in a compact structure, distinct outlines, smooth surface finish, and superior mechanical properties. These features are especially beneficial when casting large, thin-walled parts;
4)The elimination of feeding risers allows for an increased metal utilization rate, reaching levels of 90% to 98%;
5)This method offers advantages such as low labor intensity, improved working conditions, simplified equipment requirements, and the potential for mechanization and automation.
Application of Low-pressure casting
Mainly traditional products (cylinder heads, hubs, cylinder frames, etc.).
Centrifugal casting
It is a method of casting wherein liquid metal is introduced into a spinning mold, leading to the filling and solidification of the mold through the action of centrifugal force.
Manufacturing processes of Centrifugal casting
Technical features of Centrifugal casting
◆Advantage
1)There is almost no metal consumption in the gating system and riser system, which improves the process yield;
2)The resulting castings have a high density, reduced occurrence of defects like porosity and slag inclusions, and superior mechanical properties.
3)It is convenient to manufacture composite metal castings such as barrels and sleeves.
◆Disadvantage
1)There are certain limitations when used to produce special-shaped castings;
2)The diameter of the inner hole of the casting is not accurate, the surface of the inner hole is relatively rough, the quality is poor, and the machining allowance is large;
3)Castings are prone to specific gravity segregation.
Application of Centrifugal casting
Initially, centrifugal casting was employed for the production of cast pipes. Both domestically and internationally, centrifugal casting technology finds applications in various industries such as metallurgy, mining, transportation, drainage and irrigation machinery, aviation, national defense, and automotive. It is utilized to manufacture steel, iron, and non-ferrous carbon alloy castings.
Vacuum Casting
It is an advanced die-casting process that improves the mechanical properties and surface quality of die-casting parts by eliminating or significantly reducing the pores and dissolved gases in the die-casting parts by pumping out the gas in the die-casting mold cavity during the die-casting process.
Manufacturing processes of Vacuum Casting
Technical features of Vacuum Casting
◆Advantage
1)Eliminate or reduce the pores inside the die casting, improve the mechanical properties and surface quality of the die casting, and improve the coating performance;
2)In order to reduce the cavity's back pressure, alloys with lower specific pressure and subpar casting performance can be utilized, enabling the die-casting of larger castings using smaller machines.
3)The filling condition is improved, and thinner castings can be die-cast.
◆Disadvantage
1)The mold sealing structure is intricate, making the manufacturing and installation process challenging, resulting in higher costs.
2)If the vacuum die casting method is not properly controlled, the effect will not be very significant.
Lost Foam Casting
It is to bond and combine paraffin or foam models similar in size and shape to castings to form model clusters. After brushing refractory paint and drying, they are buried in dry quartz sand for vibration molding, and poured under negative pressure to vaporize the model. Liquid metal A novel casting technique that fills the mold and transforms into a casting upon solidification and cooling.
Manufacturing processes of Lost Foam Casting
Technical features of Lost Foam Casting
1)The casting exhibits exceptional precision and eliminates the need for sand cores, resulting in reduced processing time.
2)No parting surface, flexible design and high degree of freedom;
3)Clean production, no pollution;
4)Reduce investment and production costs.
Application of Lost Foam Casting
It is suitable for the production of precision castings of various sizes with complex structures. The types of alloys are not limited, and the production batches are not limited. Such as gray cast iron engine case, high manganese steel elbow, etc.
Any questions,please feel free to ask.
Yuki Yang
