Design Iron Rule: Customer drawings and samples are the only legal basis for mold design, and all technical decisions must be based on them. Following is a systematic design implementation framework:
I. Standard Process for Product Analysis

 

1. Dimensional Accuracy Implementation Specifications

Note: Shrinkage Selection Formula: S_Actual = S_Nominal + α·ΔT·L
(α: Plastic Expansion Coefficient, such as PP takes 9×10⁻⁵/℃)
II. Key Technical Points of Product Characteristics
1. Demolding angle design matrix

2. Wall thickness balance control
Golden ratio:
■ Base wall thickness = 0.6×flow length ratio×material coefficient
■ Reinforcement rib = 0.6×main wall thickness
■ Corner R angle = 0.3×wall thickness
Testing standard:
► Ultrasonic thickness gauge scanning tolerance ±0.05mm
► CAE mold flow analysis shear rate <10000s⁻¹
III. Material decision tree
graph LR
A[Plastic type] --> B{Characteristics}
B -->|High wear| C[Carbide insert]
B -->|High glass fiber| D[Chrome plating/DLC coating]
B -->|Corrosive| E[Corrosion-resistant steel]
A --> F[Batch]
F -->|>500,000| G[Pre-hardened steel + TD treatment]
F -->|<100,000| H[Ordinary P20 steel]
Quick reference for mold steel selection:

IV. Batch production response plan
Mold cavity number calculation model
Optimal cavity number N = min(
⌊T_max/(t_cycle+t_aux)⌋,
⌊F_clamp/(P_inj×A_part)⌋,
⌊W_max/(W_part+W_runner)⌋)
Parameter description:
T_max: Daily production time (seconds)
t_cycle: Single piece cycle
F_clamp: Injection molding machine clamping force
A_part: Single piece projection area
Case: 10-hour production plan, 8-second cycle, 1000T injection molding machine
→ N = min(45000/8, 1000/(30 * 0.05)) = min(32,66) = 32 holes
V. Injection molding machine matching list

VI. Implementation specifications for special needs
Electroplating mold design
Technical points:
► Runner system: H-type layout (auxiliary runner width 4mm)
► Gate design: latent gate + cold material hole
► Separation scheme: pre-break line (depth 0.3×wall thickness)
Notes:
■ Laser cutting separation is required after electroplating
■ Stress analysis is required for pre-break point
Surface treatment process selection

VII. Design verification list
Dimension traceability system
Two-way verification of key dimensions and drawings (tolerance ±0.002mm)
Sample 3D scanning comparison (deviation chromatogram)
Molding simulation prediction
CAE must-check items:
□ Weld line position prediction
□ Shrinkage index <0.05
□ Ejection stress <30% of material yield strength
Design risk matrix

Final confirmation: After obtaining written approval from customer, mold is opened, and first piece needs to undergo a full dimensional inspection report (CPK≥1.33)
This specification can ensure that mold design has a one-time pass rate of ＞95%, and number of mold trials is ≤3 times, meeting development needs of various industrial products.