Steel shot filling shell molding line is a specific type of shell molding process that incorporates steel shot as a backing material to support the thin, brittle shell mold during casting. This approach enhances the structural integrity of the mold, allowing it to withstand the pressures and stresses of molten metal pouring without deformation or cracking.
Description of Shell Mould Casting Line
The shell moulding line is developed for continuous prodction of shell moulding process with layout of continuous line or open line.The whole line is equipped with bottom sand filling and vibrating table,core setting station,top sand filling & vibrating station,pouring station,cooling,and flask turnover device;as well the sand preparation system,resin coated sand reclaimation system.
The steel shot filling process is a process in which the core is placed in the flask and the steel shot is filled to reinforce the core.After pouring,the castings are cooled by steel shots.The cooling speed is faster and the process has better venting.The steel shot can be recycled and reused. Compareing to normal sand casting process,the shell moulding process has advantages of lower investment,compact area occupation,easy operation,high efficiency,low sand consumption,less dust pollution,and use noise.And the castings have better surface,better dimension accuracy,and good material properties.
Shell core foundry process is to use hot core box process equipment for shell core of precoated sand.Its working process of sand filling and compaction is done at the same time, and immediately on the hot core box of hardening, reduce labor intensity, flexible operation of portable, easy to grasp, use electric heating, temperature automatic control, work easy to keep clean, create conditions for core making process of mechanization and automation.A cycle only ten seconds to a few seconds, can be produced for casting cores.With shoot core machine manufacturing core size precision, smooth surface.Widely used in foundry machinery.
How Shell Molding Line Works?
The process is an extension of the standard shell molding technique but includes an additional step for filling the mold cavity with steel shot
Pattern Heating and Coating:
A heated metal pattern is coated with a sand-resin mixture to create a thin, rigid shell mold.
Shell Curing:
The shell mold is hardened and removed from the pattern, forming one or more shell sections. These are assembled to create the complete mold.
Steel Shot Filling:
The shell mold is placed into a container or flask.
Steel shot (small metallic spheres) is poured into the flask to completely surround the shell mold, filling the void between the shell and the outer flask.
Compaction:
The steel shot is compacted, often using vibration or tamping, to ensure even distribution and support around the mold.
This backing prevents the thin shell mold from collapsing under the weight and pressure of molten metal.
Molten Metal Pouring:
Molten metal is poured into the shell mold cavity. The steel shot provides excellent mechanical support, especially for complex or heavy castings.
Cooling:
The metal solidifies, and the steel shot absorbs some of the heat, reducing the risk of thermal stress and deformation.
Shell and Shot Removal:
After cooling, the shell mold is broken apart to retrieve the cast part.
The steel shot is collected, cleaned, and often reused in subsequent cycles.
Finishing:
The cast part undergoes cleaning and any required finishing operations to achieve the desired specifications.
Why Use Steel Shot in Shell Molding?
Structural Support:
The thin shell mold can be fragile, especially for large or complex castings. Steel shot provides a robust support structure, allowing the mold to maintain its shape.
Heat Absorption:
Steel shot has good thermal conductivity, which helps to evenly distribute heat and reduce thermal shock to the mold during pouring and cooling.
Reusability:
Steel shot is durable and can be reused multiple times after cleaning, making it cost-effective.
Improved Casting Quality:
By stabilizing the mold, the use of steel shot minimizes defects like warping, deformation, or cracking, leading to higher-quality cast parts.
Advantages of Shell Molding:
High dimensional accuracy and surface finish.
Ability to cast intricate shapes and thin sections.
Reduced post-processing compared to other sand casting methods.
Can produce large volumes of parts with consistent quality.
Applications:
Steel shot filling in shell molding lines is often used in industries requiring high-quality castings with complex geometries, such as:
Automotive industry: Engine blocks, cylinder heads, and gearbox components.
Aerospace industry: Turbine blades and other high-precision parts.
Industrial machinery: Pump housings and valve bodies.
Energy sector: Wind turbine components and power plant parts.
This process is particularly advantageous for castings where high precision, dimensional accuracy, and surface finish are critical.