Iron castings can be referred to as products made out of
melted iron molecules. These molecules are, first, poured into mold and allowed
to cool. They are then extracted. The casting properties depend a great deal on
the foundry practice. They also depend on the cooling rate. Iron contains huge
carbon concentrations. This content facilitates melting, simplicity of casting,
and machining. Iron casting designs have a great variation owing to the
property of iron to resist shrinkage during the process of cooling. The end
product attains a great reputation for its strength and durability. Tensile
strength ranges between 20,000 psi and over 60,000 psi. The values of hardness
(without heat treatment) range between 100 and 300 BHN.
Some factors need to be considered while buying iron
castings. The first thing on the agenda should be, checking the quality of
foundry used in products and procedures. This should be done because foundry
practices determine the casting properties. The consumer might have a tough
time in finding the apt one. Secondly, the concentration of carbon should be
looked into. The percentage of carbon commonly ranges between 2.5 and 4%. An
addition of even 0.1% would cause the tensile strength to decrease by around 2700
psi. Casting procedures differ from foundry to foundry.
Green sand molding is the most commonly used type of
casting. Normally, small and medium sized products are produced using this type
of casting. Shell molding is preferred for bigger applications. Shell molding
facilitates cooling of the mold containing heated metal. This process gives a
better finishing to the final product as compared to all the other processes.
Centrifugal casting is used for producing big cylinders and pipes. Both,
producer and consumer would get highly satisfied if a proper blend of correct
casting process and reputed foundry is made.
Iron castings are utilized extensively in machinery,
automotive, and agricultural industry. Parts such as turbine and pump housings,
dynamometer bases, compressors are made out of iron castings. Majority of
manufacturers have the caliber to go for high and low production outputs. They
are also entitled to go for short order runs. There are standard prototypes
ensuring customer satisfaction and accuracy. Some manufacturers provide
finishing services like galvanizing, painting, and machining as well. In
general, iron castings include alloy casting, ductile castings, and malleable
castings. There are some terms relating to iron castings. They need to be known
in order to get a fair idea of iron.
Number (BHN): It can be defined as the method used for measuring the
hardness of iron. For iron castings, a metal ball of 3000Kg is put on a flat
iron piece. After the removal of ball, indentation observed is recorded. This
measurement indicates the value of hardness.
Tensile strength can be defined as the quantity of bending and stretching
undergone by a material before tearing or breaking. Here the metal is iron.
Elasticity: It can be defined as the ratio of stress to strain. This
value determines the elasticity as well as the stiffness of the concerned