30-06-2012, 11:43 AM
Metal Casting and Foundry
Metal Casting and Foundry.pdf (Size: 820.14 KB / Downloads: 467)
Objective:
The main objective of this experiment is to enhance the practical knowledge of the
students in the field of metal casting technology and to review the basic principals for
the design of casting patterns, feeding systems and gating systems, in addition to the
investigation of the main factors affecting the function of such casting elements.
Background:
For more information about the subject of the experiments, it is recommended for the
student to review chapter five of the text.
Theory:
It is a popular mean by which a material is converted into a final useful shape; a
solid is melted, heated to a proper temperature, and sometimes treated to modify its
chemical analysis. The molten material, generally metal, is then poured into a mold
cavity, which contains it in proper shape during solidification. The resulting product can
have virtually any configuration the designers want (patterns). In addition the resistance
to working stresses can be optimized, properties can be controlled (heat treatment), and
a good appearance can be produced (fettling and finishing).
Casting terminology.
Figure 3 illustrates the cross section of a typical two-part casting mold and incorporates
many features of the process. Parting line, cope, drag, mold cavity, riser, gating system,
sprue, pouring cup, and many other features are shown.
Design of Casting process
The process for making a casting is designed in a definite sequence, which includes the following:
A. the drawing of the part to be cast, such a process is the main process
document.the drawing is define all the features of the casting process and is the basis for
the design and manufacture of the moulds and patterns and selection of other appliances,
which are needed for the manufacturing of the casting mold (flask,template,etc.).The
elements of foundry technology indicated on the drawing should specify the following:
1. The best parting plane for the mold and pattern.
2. The positions of the mold for pouring which is depending on the shape
of casting, kind of metal, gating system geometry, specifications of cast
metal density, surface finish and many others.