Mold Design & Engineering

Buy Injection Mold Design & Engineering Services on Junying

Boost your plastic parts for production with professional injection mold design and engineering services from Junying. Our expert team helps you create high-quality, moldable designs that reduce production costs, accelerate time-to-market, and ensure precision manufacturing. From prototyping to full-scale production, we guide you through every stage of the injection molding process, offering automated design analysis, moldability feedback, and certification-ready solutions. Take advantage of our advanced facilities and collaborative approach to achieve superior part quality and cost-efficiency.

What is Mold Design and Manufacturing?

Mold design and engineering is the process of creating and developing molds used to shape and produce plastic or metal parts with precision and consistency. It involves designing the mold’s cavities, cores, cooling channels, ejection systems, and gating mechanisms to meet specific product requirements, material properties, and production volumes. Skilled engineers use CAD software, mold flow analysis, and prototyping to optimize part manufacturability, ensure dimensional accuracy, and minimize defects. Effective mold design and engineering not only improve product quality but also enhance production efficiency, reduce costs, and extend the lifespan of the molds.

Mold Design

Advantages of Injection Molding Design

Injection molding design offers numerous advantages, including ensuring product functionality and reliability by assessing part usage, strength, and environmental requirements to meet performance demands. It enhances cost efficiency through simplified part and tool designs, minimizing downtime and extending mold durability. Quality control is improved with systematic design reviews, CAD checks, and in-process inspections, while flexibility in material use allows engineers to select the right resins for demanding applications. Experienced engineers can quickly solve challenges related to gating, cooling, and venting, and innovative technologies like 3D printing and hybrid processes enable faster prototyping and mold creation. With seamless in-house support, modifications and improvements can be implemented rapidly, reducing downtime and ensuring timely delivery for customers.

Mold Engineering

Types of Molds

Single-Cavity Mold

Produces one part per cycle. Simple design, low cost. Best for low-volume production and large plastic parts.

Dedicated Multiple-Cavity Mold

Produces identical parts in multiple cavities. Balances plastic flow and supports controlled processing. Ideal for high-volume production and small parts. Increases productivity and yield rate.

Family Multiple-Cavity Mold

Each cavity produces a different part. Suitable for prototypes and low-volume runs. Allows multiple parts of the same material in one cycle. Historically difficult to balance, but modern gating tech has improved performance.

Two-Plate Mold

Simple design with two plates and a parting line. Commonly used for injection molding. Durable, cost-effective, and easy to maintain.

Three-Plate Mold

Includes an additional stripper plate to separate runners. Features double-action ejection; runners do not eject with the part. Reduces secondary operations and cycle time. Higher initial cost but excellent for high-volume production and quality surface finish.

Stacked Mold

Uses multiple layers of cavities within one mold. Produces multiple identical parts per cycle. Maximizes machine efficiency and output.

Hot Runner Mold

Uses heated runners to keep material molten inside the mold. Eliminates waste from runners (“runnerless mold”). Higher cost and more complex maintenance. Best for mass production and minimizing material waste.

Cold Runner Mold

Runners are unheated, and material solidifies with the part. Requires runner removal (extra process and potential waste). Lower cost, easier to change materials. Suitable for low-volume production and simpler operations.

Applications of Injection Mold Design

Automotive Industry: High durability, heat resistance, and dimensional accuracy are required for vehicle safety and performance.
Consumer Goods: Ability to create ergonomic designs, smooth finishes, and cost-effective large-scale production.
Electronics and Electrical Industry: Precision and insulation properties of molded plastics are essential for safety and performance.
Medical Industry: Provides sterile, biocompatible, and high-precision parts suitable for strict health standards.

Packaging Industry: Ensures lightweight, durable, and uniform packaging that is fast and economical to produce.
Aerospace Industry: Reduces weight while maintaining strength and consistency for high-performance environments.
Industrial Applications: Provides durability and precision for mechanical and structural parts.
Construction Industry: Strong, weather-resistant, and cost-efficient for large-scale building projects.

What Materials Commonly Used in Injection Molding Design?

1020 Carbon Steel – For ejector plates and retainer plates; easily machined and welded; carburize if hardening is needed.
1030 Carbon Steel – Mold bases, ejector housings, clamp plates; stronger than 1020; can be hardened to Rc 20–30.
1040 Carbon Steel – Support pillars; good compressive strength; can be hardened to Rc 20–25.
4130 Alloy Steel – Cavity/core retainer plates, support plates, clamping plates; Rc 26–35.
6145 Alloy Steel – Sprue bushings; Rc 42–48.
S-7 Tool Steel – Shock-resistant, wear-resistant; interlocks and latches; Rc 55–58.
O-1 Tool Steel – General-purpose, small inserts and cores; Rc 56–62.
A-2 Tool Steel – Hobs and slides; good abrasion resistance; Rc 55–58.
A-6 Tool Steel – Optical-quality cavities and cores; Rc 56–60.
D-2 Tool Steel – High chromium/carbon; gate inserts, lifters, slides; Rc 58–60.
H-13 Tool Steel – Ejector pins, sprue pullers, leader pins; annealed 15–20 Rc, hardened up to 60 Rc.
P-20 Tool Steel – Prehard, cavities, cores, stripper plates; Rc 28–40; good machinability and polishability.
420 Stainless Steel – Chemical-resistant applications (e.g., PVC molding); cores and cavities; annealed 15–25 Rc, hardened 55–60 Rc.

Why Choose Our Custom Mold Design & Engineering Company?

Affordable Pricing

Get high-quality mold design and engineering services at competitive, cost-effective rates.

Expert Engineering Team

Experienced engineers ensure precise, moldable designs tailored to your product requirements.

Full-Service Support

From prototyping to production, we handle every stage of the injection molding process.

Fast Turnaround

Efficient workflows and advanced technology reduce lead times, helping you bring products to market faster.

Reliable Customer Service

Dedicated support ensures smooth communication, on-time delivery, and satisfaction every step of the way.

FAQ

1. What are the main components of a mold?

A mold typically includes:

Cavity and Core – Define the part’s external and internal features with high accuracy.

Cooling Channels – Maintain proper temperature to prevent defects and extend mold life.

Ejection System – Removes parts efficiently without damage.

Gates and Runners – Control material flow for proper filling and minimal defects.

2. How much does it cost to create a mold?

The cost depends on mold size, complexity, material, and production volume. Simple single-cavity molds for low-volume runs are relatively inexpensive, while high-precision, multi-cavity molds for mass production can be significantly more expensive.

3. What is the role of a mold design engineer?

A mold design engineer is responsible for creating, updating, and repairing mold designs. Their work includes maintaining, repairing, and installing molds, designing fixtures for secondary operations, and developing 3D files for Design for Manufacturability (DFM) processes.

4. How does mold design impact production efficiency?

A well-designed mold improves cycle times, reduces scrap, and minimizes secondary operations. Efficient cooling layouts, proper gating, and durable material selection all contribute to faster production and consistent part quality.

5. What are common molding defects?

Injection molding can face issues such as:

Blisters – Raised surface zones due to overheating.

Burn Marks – Black/brown areas from poor venting or high injection speed.

Color Streaks – Uneven mixing of plastic and colorant.

Delamination – Weak layered surfaces from material contamination.

Flash – Excess thin material caused by tool damage or improper clamping.

Embedded Contaminants – Foreign particles inside parts.

Flow Marks – Wavy patterns from slow injection speeds.

Jetting – Deformed parts from turbulent flow.

Polymer Degradation – Breakdown due to excess moisture or heat.

Sink Marks – Depressions in thicker sections from low holding pressure.

Short Shots – Incomplete filling from low pressure or material shortage.

Splay Marks – Silver streaks caused by moisture in resin.

Stringiness – Residual material from high nozzle temperature.

Voids – Air pockets caused by low holding pressure.

Weld Lines – Weak, discolored lines where flow fronts meet.

Warping – Twisted parts caused by uneven cooling or overheating.