Sunday, February 20, 2011
By
st_fanuc
casting,
guide,
machine design
The most important aims in designing aluminum castings are to plan components for ease of casting production and to improve casting soundness. Planning arrangements of sections so that progressive solidification is toward the heavier sections helps reach these objectives.
This principle should be adhered to when designing for joining and changing sections. Sharp corners should be filleted because fillets prevent cracks, tears and shrinkage at re-entry angles. Additionally, make corners more moldable, and reduce stress concentration in the casting when in service. Fillets should be large enough to meet engineering stress requirements and reduce stress concentration, but not so large that they cause shrinkage.
Read more
Sunday, February 20, 2011
By
st_fanuc
casting,
machine design
Many metal castings meet the specified property requirements in their as-cast form, but there are times when even the cleverest use of the casting process and alloy will leave a part lack of the requirements. In these instances, thermal treatment can change the mechanical properties to meet those critical needs.
Heat treatment consists of heating and cooling that enhances a material’s strength, consistency or ductility. The type of heat treatment required by a casting depends on the alloy and the final properties required.
Read more
Sunday, February 20, 2011
By
st_fanuc
casting,
machine design
The fundamental process of casting consists of five basic elements
• Molding—The mold cavity must be formed from a material that will withstand the operating temperatures and conditions of the chosen casting process and metal.
• Pouring—The molten metal is poured into the mold and travels through its passages to fill the mold cavity.
• Solidification—During the solidification process, the metal cools and becomes a solid shape.
• Mold Removal—The cooled casting is removed from the mold.
• Secondary Operations—The casting is trimmed, cleaned, heat-treated, machined, inspected, painted, etc.
These five basic elements are supported by design and fabrication of the patterns and cores for the mold, the fabrication of the mold cavity and the melting of the metal.
Read more
Sunday, February 20, 2011
By
st_fanuc
casting,
machine design
Metal casting is a manufacturing process in which metal is melted and poured into molds where it solidifies into geometrically complex components.
In terms of component design, casting offers the greatest amount of flexibility of any metal forming process. The casting process is ideal because it permits the formation of streamlined, intricate, integral parts of strength and rigidity obtainable by no other method of fabrication. The shape and size of the part are primary considerations in design and in this category; the possibilities of metal castings are unsurpassed. The flexibility of cast metal design gives the engineer wide scope in converting ideas into an engineered part.
The freedom of design offered through the metalcasting process allows the designer to accomplish several tasks simultaneously. These include the following:
• Freedom of design to optimize functionality and manufacturability.
• Net or near-net shape design.
• Intricate components can be produced as single cast part.
• Few restrictions on part weight or size
• Almost all metals and alloys can be cast.
• Optimal appearance.
Read more
