What is Plastic Molding and Its Types?

 

Types of Plastic Molding

The most popular types of processes in plastic molding are injection molding, blow molding,

rotational molding, Compression molding, Extrusion molding & Thermoforming. Rotational

Molding Rotational Molding also called roto-molding. It is a process for producing large hollow

parts and products by using a powder or liquid resin into a metallic mold and revolving it in an

oven until the resin coats the internal wall of the mold. The constant rotation of the mold creates force

forming even-walled products. Once the mold cools, the hardened plastic is far away from the

mold. Very little material is wasted during the method, and excess material is usually re-used,

making it economical and environmentally friendly.

 Common Uses for Rotational Molding:

Rotational molding is commonly used to make large hollow plastic products like bulk container storage tanks, car parts, marine buoys, pet houses, recycling bins, road cones,

kayak hulls, and playground slides. 

Rotational Molds Are Highly Customizable And Cost Effective. The mold itself is

often highly intricate to facilitate the molding of a good range of products. Molds can include

inserts, curves, and contours also as logos and slots for plastic or metal inserts to be placed

after a product is molded. Tooling costs are much less in rotational molds than injection and

also in blow molds. The results are less initial start-up costs and cost-effective production runs

even when making as few as 25 pieces at a time.

Injection Molding:

Injection molding is the process of creating custom plastic parts by injecting molten plastic

the material at high into a metal mold. Just like other sorts of plastic molding, the plastic in the

molten state is injected into the mold, it is cooled, and opened to reveal a solid plastic

part. The process is analogous to a Jello mold which is filled then cooled to make the ultimate

product. 

Common Uses for Injection Molding

 Injection molding is usually used for creating very high volume custom plastic parts.

Large injection molding machines can mold car parts.

Smaller molding machines can produce very fine tolerances & precise plastic parts for

surgical applications. In addition, there are many sorts of plastic resins and additives that

will be utilized in the injection molding process, increasing its flexibility for designers and

engineers. Injection molds, which are usually made up of steel or aluminum, carry a hefty

cost. However, the value per part is extremely economical if you would like several thousand

parts per annum. Injection molding tooling takes more time approx 45days to manufacture.

Blow Molding

This is a method of making hollow, thin-walled, and custom plastic parts. It is mostly used

for producing products with a uniform wall thickness & where the shape is most important.

The process of blow molding is based upon the same principle as glass blowing.

Blow molding machines heat up the plastic and inject air blowing up the hot plastic like

a balloon. The plastic is blown into a mold and as it expands, it pushes against the walls

of the mold getting its shape. Plastic ballooning fills the mold, it is cool off and tempered,

and the part is ejected. This complete process takes less than two minutes. So an average

12hr/day can produce approx 1440 pcs.

 Common Uses for Blow Molding

Blow molding is used to manufacture bottles, plastic drums, & fuel tanks. If you need

unlimited plastic bottles, then this process is for you. It is fast and economical and mold cost

is also lesser than an injection molding, but more than rotational molding… sometimes

it is high 6 to 7 times.

Watch Short Videos: Industries best practices and operation Videos.