Application
Including EV three-electric systems
High-voltage connectors, ECU and sensor housings, and battery module brackets: glass-filled resin. Dimensional stability and hydrolysis resistance are critical constraints.
Common components
High-voltage connectors, ECU and sensor housings, battery module brackets, busbar sleeves
Common resins
PA66+GF, PA9T, PA6T, PPS, LCP
Shot Weight and Wall Thickness
1–50 g per part
housings 0.8–2.0 mm
thin-wall connectors 0.2–0.5 mm
Shot weight, wall thickness, and flow ratio determine the gate; appearance and cleanliness requirements determine the nozzle type.
At the weld line, fibers do not bridge the joint, reducing strength to that of the resin alone; uneven fiber orientation also induces warpage during assembly. Moving the gate alters the flow pattern and changes fiber orientation again.
Excess moisture degrades the melt and causes silver streaks; prolonged residence time has the same effect. Drying and barrel residence time are more critical than increasing tip temperature.
Insertion force and housing fit depend on dimensional stability. If mold temperature, packing, and cooling time are not optimized, increasing melt temperature only adds internal stress.
Different gate practices are required for different components and requirements within the same industry. This table is organized by component, not by model.
Part | Common resins | Size and cavitation | Practice |
|---|---|---|---|
| Part High-voltage connectors | Common resins PA66+GF, PA9T | Size and cavitation 0.2–0.5 mm, multi-cavity | Practice SD or TP: gate position determined by pin layout; VG sequencing for critical appearance requirements. |
| Part ECU and sensor housings | Common resins PA66+GF, PPS | Size and cavitation 0.8–2.0 mm | Practice SD straight-through; position weld seams away from sealing and assembly surfaces |
| Part Battery module brackets | Common resins PA66+GF | Size and cavitation 1.5–3 mm | Practice SD straight-through; focus on warpage and shrinkage around inserts |
| Part Busbar sleeves | Common resins PA66+GF | Size and cavitation 0.8–1.5 mm | Practice SD; calculate gate position based on flow ratio for long-flow parts |
Each item first explains the mechanism, then our scope of work. Mold temperature, clamping, and drying are out of scope.
At the weld, glass fibers do not cross; strength depends on the weld angle and melt-front temperature.
PRACTICE
Place the weld line in a non-load-bearing area. If its position must be fixed, use VG sequencing to move the weld to the target location. Do not compensate with higher melt temperatures.
Fiber orientation and uneven cooling combine and relax after ejection.
PRACTICE
Run flow analysis first to balance gates and runners; then adjust packing time and mold temperature independently. The hot runner system controls only the gate section, not the mold temperature.
The gate section runs cold, causing the melt to cool before filling.
PRACTICE
Toggle gate-section heating on and off during the molding cycle; the straight-through nozzle has no reduced section. Isolate cold material from runner temperature, mold temperature, and stopped-machine residue.
Scope of services and exclusions are outlined before the proposal and quotation.
Open SD and TP, plus valve-gate VG and PVG; all suitable for automotive electronics. Specific model selection depends on gate position, appearance requirements, and cavitation.
Mold temperature, melt temperature, clamping force, and drying are part of the mold and molding process. A hot runner cannot replace them.
The no-clogging guarantee applies only to straight-through nozzles. Pin-point and valve-gate types have small sections and mating surfaces, so we cannot guarantee they will be clog-free.
We explain any out-of-range calculations at the proposal stage.
Articles on materials and applications in this industry, sorted by newest first.
As automotive electronics evolve, LCP is increasingly used in under-hood and high-density connectors. Its heat resistance, dimensional stability, flame retardancy, and flow properties make it well-suited for this application. However, issues like stringing, drooling, and gate clogging remain production challenges.
Dark brown or black patches with halos at part ends or weld lines that cannot be cleaned and appear consistently, caused by compressed gas heating the melt to carbonization temperatures.
Flat plates warp, long bars bend, and frames twist even when individual dimensions are within tolerance. This warpage results from uneven shrinkage.
Within the same part, some areas shrink more than others, causing thickness variations, slight local depressions, and inconsistent overall dimensions. This condition is known as uneven shrinkage.
Practice and results only; customer names are not disclosed.
Customer case studies for this industry are being prepared.
Send the mold 2D layout, part 3D data, resin grade, wall thickness (including the thinnest section), number of cavities, shot weight, current process parameters, and defect photos.