Terms Used in the Injection Molding and Mold Building Industry

Injection Mold & Plastic ComponentBelow is a list of frequently used terms in the injection molding and mold building industry to help when discussing your injection molding project.

EDM (Electrical Discharge Machining) which cuts metal from a work piece with a series of electrical sparks that precisely shapes the material into simple or complex geometrics. 

High Speed Machining is cutting metal by using recent speed technology that allows machining centers to do more work.

Swiss Screw Machining utilizes a lathe type metalworking machine using multiple spindles in the manufacturing of small precision parts; these are CNC controlled for one time setup with very minimal operator assistance.

Mold Simulation is the ability to simulate the mold fill process that accounts for multiple injection molding variables.  The data produced provides a basis for setting the actual process variables for use in the injection molding process.

MUD Unit (Master Unit Die) – These are standard frameworks for tools, allowing for custom machined inserts for specific components.

Hot Runner System is an assembly of heated components used to inject molten plastic into cavities of the mold.  Hot runners usually make a mold more expensive to manufacture and run but allow savings by reducing plastic waste and by reducing the cycle time.

Two Plate Mold means there is one parting line and the mold splits into two halves.  The sprue, runners, gates and cavities are all on the same side of the mold.

Three Plate Mold is a mold which has a runner plate in between a moving half and a fixed half.  These molds will have two parting lines and are used because of their flexibility in gating location. 

Unscrewing Molds are used when there is a requirement for male or female threads on a plastic component.

Action Molds have some sort of mechanical action incorporated into the design, when a hole, slot, undercut or thread is needed that is not perpendicular to the parting line

Stack Molds are two molds connected inline.  It has two parting lines and double cavitations, so it produces twice as many components.

Custom Injection Molding is a manufacturing process for producing custom components from plastic materials by injecting molten plastic into a mold, cooling the plastic and ejecting the cooled component from the mold.

Insert Molding is the process of putting a metal insert into a mold and molding plastic around the insert.  Since multiple parts are manufactured together this eliminates the need for a secondary assembly application.

Over Molding is the process of molding over an existing part plastic/plastic or plastic/metal.  However, the generally accepted definition of over molding is the production of an injection molded part that seamlessly combines a rigid plastic with rubber-like elastomers. 

Family Molding is an injection molding process that utilizes a mold that contains various shaped cavities to mold all the plastic components for one completed part.  Family molds can be used only when the different plastic components are made from the same material.

Clean Room Molding is the process used for medical molding using a HEPA filter system to filter air; the operator running the press wears gloves, gowns, masks and booties to protect from contaminants coming in contact with the parts.

Contract Manufacturing is manufacturing components and subcomponents by one company under the label or band of another company.

Crescent Industries is a single source solution for your plastic injection molded components providing mold building and custom injection molded components to the medical, pharmaceutical, defense, safety, and aerospace industries.  For more information on Crescent Industries capabilities, please click here.

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About Frank Spears

The next time your business calls for an injection mold, explore the opportunity that Total Solution Plastic offers to reduce cost, minimize procurement hassles and get your injection mold to specification and on time. You have my word on it.