What is the Key to Plastic Injection Molding Design

Why Design is Key to Plastic Injection Molding Design | GreenLeaf Industries

Why Design is Key to Plastic Injection Molding

Before plastic parts are manufactured,  a solid design is needed. This design is then used to build an injection mold as per a customer’s given product specifications. This is what is known as injection molding design.

The criteria for injection molding design

Injection molding design is done based on a number of criteria which is determined by a design engineer. The engineer looks at a design and makes changes and recommendations according to product requirements. The criteria engineers use are;

  • The purpose of the plastic part; will it be a product in itself or part of a larger one?
  • What are the required dimensions and tensile strength?
  • Will the part be able to stand up to weather elements, chemicals, and pressure?

Injection molding design is done based on these criteria. Apart from the design of the plastic part, the vents, gate placement, and mold cavities also depend on the type of resin. It is a challenge to take all these factors into account and come up with the required injection molding design.

Steps to injection molding design

When a request for a new part or concept is received, the first step is checking that the part is moldable. A design engineer will then make recommendations to the customer with the aim of making the part as simple and strong as possible.

The simpler a tool is, the less it will cost to make and the stronger it is, the less downtime it will have. It will also be more efficient. The key to a great design is analyzing the function or functions of a part and adjusting the design accordingly while ensuring the design is mold friendly.

Common problems

Some of the common problems that are experienced in designing a high-production mold are venting, cooling and gating. The good news is that each of these factors can be changed or adjusted in order to meet the needs of a customer.

More Plastic Used in Manufacturing | Injection Molding Design | GreenLeaf IndustriesMore plastic, less metal

More and more, manufacturers have turned to plastics rather than metals which used to be more popular. Injection molding designs have changed to accommodate this. In order to satisfy the needs of a client, items like a glass filled to various durometers of the plastic and other alternatives are used.

Other advances

Other changes in this sector have been advancements in 3D printing and the use of new polymers and additives. 3D printing is still new. What it does is that it makes it possible for you to print a working model of the required part. The difference is that you will be able to print the mold to manufacture high-volume injection mold parts. Already, there is a hybrid process that combines what is known as 3D laser sintering and high-speed milling which gives a very precise cavity.


The question of quality is imperative. Quality checks are not done only at the end of the process of building a mold but during the process. Designs are put through a design review process to ensure that nothing was missed. Checks are made throughout the manufacturing process.

Turn over a new leaf


GreenLeaf Industries is an ISO 9001 registered manufacturer that consistently adheres to all its standards to provide our clients with consistent, reliable, quality automotive and industrial plastic parts.

Contact a GreenLeaf Industries expert today for exceptional engineered quality and reliable delivery, all at the best rates. We are an American injection molding company, unafraid to compete in the world market and determined to succeed. Established in 1999, we take pride in our high-quality craftsmanship and superior customer service. Contact us to discuss whether your injection molding project may be a candidate for reshoring.

GreenLeaf Industries
310 Bussell Ferry Road
Lenoir City, TN 37771
(865) 988-5661