Transfer molding Explained
Hello everyone ever wondered or for want of a better
word ‘compared’ various manufacturing process? I guess many
actually do. It makes remembering simple. You only need to
remember the minor differences which set various processes
apart.
One such process is transfer molding. This process when seen
practically is strikingly similar to Compression and injection
molding.
This process is basically a combination of injection and
compression molding.
The simple apparatus consists of a plunger or a piston which
reciprocates in a transfer pot (‘Transfer pot’ is nothing but the
barrel as in injection molding). The transfer pot has a sprue
attached to it. This sprue then opens in a mould which is already
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Prepared according to
required dimensions.
The process consists of basic steps as in the other two molding
processes. The material which is generally a thermoset (In
some cases thermoplastics may also be used) is preheated to a
sufficient temperature to make it soft. As soon as the material
softens, this near liquid material is forced into the mold by the
plunger overhead.
The plastic takes the shape of mold and it is then cured. When
the ready product is cooled to room temperature, it is taken out.
Now let us take into account its similarity with other processes.
Firstly, the process makes use of hydraulic press as in
compression molding and a Ram which forces the material in the
mold using sprue as in injection molding.
However there is one major difference in compression and
transfer that instead of loading polymer in a mold that is open the
polymer in compression molding, in transfer molding we is force
it in a closed mold after it is melted.
The mold is generally a two piece arrangement so that the
product can be removed easily.
The advantages are also mixed i.e.; it is better than compression
molding in time consumed and production capacity than
compression but injection molding consumes less time and can
produce complicated shapes than transfer molding.
Another such advantage is lower scrap produced. Quality can of
course be ensured.
Another related process is known as Resin transfer molding. It
uses unvulcanised rubber as its raw material. The only care we
should take is not to let trapped air in the mold else uniform
material density cannot be ensured.
We can very easily produce covers for electronic components,
also protective covers for pins, studs and other hardware
components.
word ‘compared’ various manufacturing process? I guess many
actually do. It makes remembering simple. You only need to
remember the minor differences which set various processes
apart.
One such process is transfer molding. This process when seen
practically is strikingly similar to Compression and injection
molding.
This process is basically a combination of injection and
compression molding.
The simple apparatus consists of a plunger or a piston which
reciprocates in a transfer pot (‘Transfer pot’ is nothing but the
barrel as in injection molding). The transfer pot has a sprue
attached to it. This sprue then opens in a mould which is already
Prepared according to
required dimensions.
The process consists of basic steps as in the other two molding
processes. The material which is generally a thermoset (In
some cases thermoplastics may also be used) is preheated to a
sufficient temperature to make it soft. As soon as the material
softens, this near liquid material is forced into the mold by the
plunger overhead.
The plastic takes the shape of mold and it is then cured. When
the ready product is cooled to room temperature, it is taken out.
Now let us take into account its similarity with other processes.
Firstly, the process makes use of hydraulic press as in
compression molding and a Ram which forces the material in the
mold using sprue as in injection molding.
However there is one major difference in compression and
transfer that instead of loading polymer in a mold that is open the
polymer in compression molding, in transfer molding we is force
it in a closed mold after it is melted.
The mold is generally a two piece arrangement so that the
product can be removed easily.
The advantages are also mixed i.e.; it is better than compression
molding in time consumed and production capacity than
compression but injection molding consumes less time and can
produce complicated shapes than transfer molding.
Another such advantage is lower scrap produced. Quality can of
course be ensured.
Another related process is known as Resin transfer molding. It
uses unvulcanised rubber as its raw material. The only care we
should take is not to let trapped air in the mold else uniform
material density cannot be ensured.
We can very easily produce covers for electronic components,
also protective covers for pins, studs and other hardware
components.
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