Process of Sand Casting

Sand casting is a process, which is used to makemechanical and vibration method. Following this
or manufacture large components and equipmentthere is a separation process, which involves the
made out of brass, aluminum, iron and bronze.parting of the cope and the drag. The pattern is
The metal is first melted and then gently pouredalso removed with utmost care.
into a mould, which is made up of sand.The main idea is to remove the pattern without
The cavity in the sand is made in the followingcausing any damage to the mould cavity. The
method. The desired pattern is made that is ofmelted metal is later poured in the cup for
wood or resin in whatever shape that the sandpouring. This is a part of the process of gating,
caster wants the part to turn out. In rare cases,which does the job of providing the molten metal
the pattern may be made of metal. This patternto the cavity of the mould. The gating process
is placed in a cavity in the sand. The cavity ishas a vertical part, which is connected with the
usually housed in a flask which is box like. Thepouring cup; this is called as the sprue. The
pattern is then packed into the moist sand. Therunners are the horizontal part and the gates are
sand retains the shape of the pattern when it isthe multiple joints to which it connects.
removed from the box. The person making theThere are vents, which provide an extension of
sand cast also will create a reservoir called a riserthe gating process. These vents do the job of
into which excess molten metal can flow. Aproviding a route for the gases, which are built up,
second mold is made for the upper part of theand the air, which is displaced into the
sand cast in a similar way.atmosphere. The cavity is made of a size slightly
The mould is usually made up of two parts. Thelarger than the desired piece in order to allow the
upper part is called as the cope and the lowermetal to contract as the metal cools to a
part of the mould is called as the drag. The line,temperature where it solidifies, which is normal.
which separates the upper part and the lowerOnce the metal has had the chance to solidify and
part, is called as the parting line. The sand in partcool, the mold is opened and the metal part is
and the core print are the things, which fill in theremoves. If there was a successful sand casting,
cope. The gating process and the core are madethe new part should be a close replica of the
to be close to the parting line. The upper part ispattern. There may be small imperfections at the
the joined to the drag and the pattern is coveredline that have to be removed with a file or
by covering it with sand. The methods, which helpgrinder.
to make the sand compact, are called the