Glossary

Clamping Force

clamp tonnagetonnage

Clamping force is the force an injection molding machine applies to hold the two mold halves shut while molten plastic is injected under pressure.

What Is a Cold Runner?

A cold runner is an unheated channel system in an injection mold that carries molten plastic from the sprue to the gates, where the plastic cools and solidifies with the parts each shot and is then ejected as scrap or regrind.

What Is a Certificate of Conformance (CoC)?

Certificate of conformity

A certificate of conformance (CoC) is a signed statement from a supplier that a shipment of parts or material meets the requirements of the purchase order, drawing and specifications.

What Is Concentricity? GD&T Definition & Status

Concentricity means that two or more round features share the same center axis; in GD&T it was a tolerance on feature midpoints relative to a datum axis, but ASME Y14.5-2018 removed the symbol.

What Is a Draft Angle? Definition & Guidelines

draft

A draft angle is the small taper added to the walls of a molded part, parallel to the direction the mold opens, so the part can release cleanly from the mold.

What Is DMLS? Direct Metal Laser Sintering

SLM (selective laser melting)DMLM (direct metal laser melting)

DMLS (direct metal laser sintering) is a metal 3D printing process in which a high-power laser selectively fuses fine metal powder, layer by layer, into a dense metal part.

What Is Deburring? Definition & Methods

Deburring is the finishing step that removes burrs—the thin raised ridges and rough edges left on a part after machining, drilling, casting, molding or grinding—and replaces them with a clean, controlled edge.

DDP (Delivered Duty Paid)

Delivered Duty Paid

DDP (Delivered Duty Paid) is an Incoterms 2020 rule under which the seller delivers goods to the buyer's named destination, cleared for import and with duties and taxes paid, ready for unloading.

What Is an Ejector Pin?

An ejector pin is a steel pin in an injection mold that pushes the finished part off the mold core after the mold opens.

What Is an End Mill? Definition, Types & Uses

An end mill is a rotating cutting tool for milling machines with cutting teeth on its end as well as around its sides, so it can cut sideways through material, not just plunge like a drill.

Elongation at Break

strain to failurepercent elongation%EL

Elongation at break is how much a material stretches before it fractures in a tensile test, expressed as a percentage of the specimen's original gauge length.

What Are EVT, DVT and PVT? Stages Explained

Engineering Validation TestDesign Validation TestProduction Validation Test

EVT, DVT and PVT are the three validation builds in hardware product development: EVT proves the design works, DVT proves it meets every requirement using production-intent parts, and PVT proves the factory can build it repeatably on final tooling.

What Is a Flash?

Flash is a thin, unwanted fin or skin of excess material on a molded or cast part, formed when molten plastic, rubber or metal is forced into a gap in the mold.

FDM (Fused Deposition Modeling)

FFF (fused filament fabrication)Material extrusion

FDM (fused deposition modeling) is a material extrusion 3D printing process that melts a thermoplastic filament and deposits it through a heated nozzle, layer by layer, to build a part.

What Is Feed Rate? Definition, Formula & Speed

Feed rate is the speed at which a cutting tool advances through the workpiece, usually given in inches or millimeters per minute.

What Is a Gate in Injection Molding?

A gate is the small opening through which molten plastic flows from the runner into the mold cavity.

What Is Glass-Filled Nylon? Properties & Uses

glass-fiber-reinforced plastic (GFRP)PA66 GF30PA6 GFglass-reinforced nylon

Glass-filled nylon is a nylon (polyamide) reinforced with short glass fibers, typically PA6 or PA66 with around 20–30% glass by weight.

What Is a Golden Sample? Definition & Use

master samplereference sample

A golden sample is an approved reference part, signed off by the customer, that represents exactly what an acceptable production part should look and measure like.

What Is a Heat Deflection Temperature (HDT)?

Heat distortion temperatureDeflection temperature under load (DTUL)

Heat deflection temperature (HDT) is the temperature at which a standard plastic test bar, loaded in bending, deflects by a set amount as it is steadily heated.

What Is IATF 16949? Automotive QMS Definition

IATF 16949 is the international quality management system standard for the automotive supply chain, published by the International Automotive Task Force in October 2016 as a supplement to ISO 9001:2015.

What Is Knurling? Definition, Patterns & Types

roll knurlinghelical knurling

Knurling is a machining process that presses or cuts a regular pattern of straight, angled or diamond-shaped ridges into the surface of a part, usually a round part turned on a lathe.

What Is Multi Jet Fusion (MJF)? Definition | NICE Rapid

MJF

Multi Jet Fusion (MJF) is a powder bed fusion 3D printing process that builds polymer parts, most often nylon PA12, by jetting a fusing agent and a detailing agent onto each layer of powder, then exposing the layer to infrared energy.

What Is Machinability? Definition & Ratings

Machinability is a measure of how easily a material can be cut to shape, judged by tool life, cutting forces and power, surface finish, chip disposal and material-removal rate, and is usually expressed as a rating relative to B1112 steel at 1.00 (100%).

What Is Melt Flow Index (MFI)? Definition

MFR (melt flow rate)MVR (melt volume rate)Flow rate ratio (FRR)

Melt flow index (MFI) is a measure of how easily a molten thermoplastic flows: the mass of polymer, in grams, pushed through a standard die in 10 minutes at a set temperature and load.

Non-Conformance Report (NCR)

NCR report

A non-conformance report (NCR) is a formal record that a part, material or process does not meet a specified requirement.

What Is a New Product Introduction (NPI)?

NPI

New product introduction (NPI) is the structured process of taking a new product from an approved design to repeatable volume production. It covers prototyping, design for manufacturability, tooling, validation builds, a pilot run and production ramp-up, with defined gates where the team confirms the design and the process are ready.

NRE (Non-Recurring Engineering)

non-recurring engineering

NRE is the one-time cost of design, engineering, tooling and setup work needed before a product can be produced, paid once per project rather than with each part.

What Is a Parting Line? Definition & Placement

parting surfacewitness line

A parting line is the line on a molded part where the two halves of the mold — the cavity and the core — meet.

What Is a Pilot Run?

pilot production

A pilot run is a small, limited production batch made on the production tooling and process before full-volume manufacturing begins.

What Is Reaming? Reaming vs Boring vs Drilling

Reaming is a machining operation that slightly enlarges an existing drilled hole with a multi-edged cutting tool called a reamer, bringing it to a precise diameter with a smooth finish.

What Is a Runout?

Runout is a GD&T tolerance that limits how much the surface of a round part varies as the part rotates 360° about a datum axis.

What Is an RFQ (Request for Quotation)?

request for quotation

RFQ stands for request for quotation: a document a buyer sends to one or more suppliers asking for a price and lead time to make a clearly defined part or product.

What Is Shot Size? Definition & Calculation

shot weight

Shot size is the amount of molten plastic an injection molding machine injects in one cycle: enough to fill every cavity plus the sprue and runners. It is measured by volume or weight and must suit the machine's barrel capacity; a shot that uses too little of the barrel leaves plastic in the heat long enough to degrade.

What Is a Sprue (Injection Molding)?

A sprue is the main channel that carries molten plastic from the injection molding machine's nozzle into the mold, feeding the runners and gates that fill the cavity.

What Are Sink Marks? Definition, Causes & Fixes

Sink marks are shallow depressions on the surface of a molded part, usually directly opposite a thick section such as a rib, boss or wall junction.

What Is Splay in Injection Molding?

silver streaking

Splay is an injection molding defect that shows up as silvery streaks or splash-like marks on the surface of a molded part. It is caused by gas in the molten plastic, most often moisture from resin that was not dried properly, and is also known as silver streaking.

What Is SLA 3D Printing? Definition & Uses

Stereolithography apparatusVat photopolymerization

SLA (stereolithography) is a 3D printing process that uses an ultraviolet laser to cure liquid photopolymer resin into a solid part, one thin layer at a time.

What Is Selective Laser Sintering (SLS)?

Selective Laser SinteringSLS

Selective laser sintering (SLS) is a powder bed fusion 3D printing process in which a laser fuses thin layers of polymer powder, most often nylon (PA12), into a solid part.

What Is a STEP File? Definition & STEP vs STL

STP.stp.step.p21Part 21 fileISO 10303

A STEP file (.stp or .step) is a neutral 3D CAD format defined by ISO 10303, the international standard for exchanging product data between design, manufacturing and inspection software.

What Is an STL File? Definition & Uses

Standard Tessellation LanguageStandard Triangle LanguageSTereoLithography

An STL file is a 3D model format that describes the surface of a part as a mesh of triangles, storing only each triangle's corner coordinates and outward-facing direction.

What Is Tensile Strength? Definition & Testing

ultimate tensile strength (UTS)

Tensile strength is the maximum pulling (tensile) stress a material can withstand before it breaks, measured in a tensile test and reported in MPa or psi; it is also called ultimate tensile strength (UTS).

What Is a Thermoplastic? Definition & Examples

A thermoplastic is a plastic that softens and melts when heated and hardens again when cooled, a cycle that is reversible and repeatable.

What Is True Position? GD&T Definition & MMC

position tolerance

True position is the theoretically exact location of a feature, such as a hole or pin, defined by basic dimensions from a datum reference frame. A position tolerance then sets a zone, usually a cylinder of stated diameter, within which the feature's actual axis or center plane must fall.

What Is an Undercut?

An undercut is any feature on a molded part that prevents it from being pulled straight out of the mold in the direction the mold opens, such as a side hole, snap-fit hook, internal groove or thread.

What Is UL 94? Flammability Ratings Explained

Standard for Tests for Flammability of Plastic Materials for Parts in Devices and Appliances

UL 94 is the UL standard for testing the flammability of plastic materials used in parts for devices and appliances.

What Is Vacuum Casting? Definition & Process

Urethane castingPolyurethane casting

Vacuum casting is a low-volume process that makes plastic parts by pouring liquid resin, usually polyurethane, into a silicone mold under vacuum so it fills fine detail without air bubbles.

What Is Wall Thickness?

Wall thickness is the distance between the opposite surfaces of a part's wall.

What Is Warpage? Meaning, Causes & Fixes | NICE Rapid

Warpage is the unintended distortion of a molded part, such as bowing, twisting or curling out of its designed shape, that appears once the part is released from the mold. It is caused by uneven shrinkage, usually from differences in wall thickness, uneven mold cooling or, in fiber-filled plastics, fiber orientation.

What Is a Weld Line?

knit line

A weld line, also called a knit line, is the seam that forms on a molded part where two separate flow fronts of molten plastic meet and fuse incompletely.

What Is Yield Strength?

yield stress

Yield strength is the stress at which a material stops deforming elastically and begins to deform permanently.