Precision Mold Inserts
machined to drawing, fitted to spec.
Huicheng manufactures mold inserts and precision insert components to controlled drawings. Parts are processed through CNC, EDM, wire EDM, grinding and inspection — with the route determined by geometry, material, heat treatment and tolerance requirement.
Small form. Tight fits.
Multiple pieces per mold.
Mold inserts and precision inserts (入子) are components fitted into a mold base to form specific features of the molded part. In connector molds, a single mold set may contain ten to fifty individual inserts — all of which must meet their drawing tolerances and fit consistently into the same pocket.
Insert manufacturing is not just about holding one dimension. It requires controlling the fit surface, the functional face, the overall form and any EDM or wire-cut profile features as a coordinated set of requirements — not individual dimensions in isolation.
From connector inserts
to complex form components.
These photographs show representative insert and precision insert components from Huicheng’s factory. Dimensions, customer references and drawing identifiers are not shown.
Representative work only. Customer drawings, names, dimensions and project identifiers are not shown.
Fit surface and functional feature
planned before the first cut.
The actual route changes by part. These stages show how requirements stay connected from drawing review through delivery.
Drawing review
Confirm fit tolerance, functional dimensions, material, hardness, datums and required reports.
Material & heat-treatment planning
Select and procure verified steel. Plan HT timing to control dimensional change before final operations.
CNC machining
Rough and finish machining of general form, holes, fit diameters and reference surfaces.
EDM & wire EDM
Profile features, internal slots, hardened contours and fine details not reachable by rotating tools.
Precision grinding
Control thickness, flatness, parallelism and critical fit dimensions after heat treatment.
Inspection & delivery
CMM or vision measurement against drawing datums. Document as agreed, then protect and ship.
Match the steel to
the application demand.
Material selection affects machinability, heat-treatment response, wear life and surface finish. These are the common insert steels processed at Huicheng:
General tooling
Good toughness and balanced machinability. Suitable for most injection mold inserts at standard hardness (HRC 48–52).
Corrosive or transparent plastics
High chromium content provides corrosion resistance. Used for PVC, transparent or food-contact applications. Can be polished to mirror finish.
High-wear applications
Excellent wear resistance at high hardness (HRC 60–62). For abrasive plastics and high-cycle insert applications.
Pre-hardened, free-machining
Pre-hardened to approx. HRC 37–43. No heat treatment required. Suitable for prototype inserts and lower-volume tooling.
High-speed tool steel
For precision pins, small inserts and fine features requiring high hardness and edge stability at HRC 60+.
What buyers usually
need to confirm.
What files are needed to quote an insert?
Provide a controlled 2D drawing and 3D model where available. Include drawing revision, material grade, target hardness, quantity, required reports and target delivery date. The fit tolerance to the mold base pocket should be stated if it differs from general tolerances.
Can Huicheng supply matched sets or interchangeable inserts?
Multiple inserts for the same position can be produced as a set to ensure interchangeability. Confirm the required dimensional consistency, inspection method and how parts will be identified when ordering.
Can heat treatment and surface treatment be included?
Heat treatment, vacuum nitriding, surface blackening, PVD and polishing can be reviewed as part of the project scope. State which operations are required and which reports must be included with delivery.
What tolerance can Huicheng hold on insert profile features?
Factory records show EDM stable tolerance of 0.002 mm, wire EDM of 0.02 mm, and surface grinding of 0.02 mm for flatness and parallelism. Profile and positional tolerance for specific insert geometry is confirmed after drawing and process review at RFQ.
Can spare inserts be ordered alongside the main project?
Yes. Spare inserts can be quoted in the same order or as a subsequent repeat order. Provide the original drawing revision and confirm whether the material, hardness and inspection scope are unchanged.
Ready to quote an insert?
Send the drawing revision, material, fit tolerances, quantity and required delivery date. Huicheng will confirm the process route and inspection scope.