Introduction

With the rapid evolution of automotive electrification and intelligence, rubber components for sealing, dust‑proofing and damping applied in lamps, engines, wiring harnesses and NEV battery packs face stricter requirements: wide temperature resistance, ozone ageing resistance, waterproof & breathable performance, tight dimensional tolerance and long‑term operational stability.

Founded in 1996, KINGTOM has over 25‑year expertise in automotive rubber‑plastic manufacturing, owning a 45,000 ㎡ production plant, IATF 16949 certification and CNAS‑accredited in‑house laboratory. We provide one‑stop custom rubber‑part solutions for multiple OEMs and Tier‑1 customerskingtomrub.... Below is our real‑world joint‑development project covering multiple automotive rubber component categories.

Project Background

Our client is an international automotive Tier‑1 supplier developing multiple ICE and new‑energy vehicle platforms, requiring four major series of custom rubber parts:

1. Automotive lamp rubber parts: headlamp rear rubber covers, breathable rubber caps, lamp sealing gaskets, weather‑strips and rubber plugs to eliminate lamp fogging, water ingress and balance internal air pressure.

2. Engine‑compartment rubber parts: corrugated air intake hoses, dust boots and suspension bushings to withstand high temperature and oil contamination under‑hood conditions.

3. Wiring‑harness rubber components: cable grommets, harness bellows and connector waterproof stoppers for cable‑penetration sealing and electrical insulation protection.

4. NEV rubber components: battery‑pack sealing gaskets, high‑voltage‑connector dust caps and anti‑shock cushion pads to meet EV standards for flame retardancy, insulation and weather resistance.

Client key pain points: multi‑category parallel development with diverse material requirements; complex part geometry demanding strict dimensional accuracy, air tightness and anti‑ageing performance. The client required a supplier capable of full‑scope service: compound formulation, tooling fabrication, reliability testing and serial production complying with IATF 16949 procedures.

Project Implementation

1. Requirement Review & Material Selection

Upon project kick‑off, KINGTOM cross‑functional team (R&D, material engineering, quality, tooling) reviewed customer drawings, working conditions and environmental test specifications.We selected proper rubber polymers for each application: modified EPDM for lamp breathable components; NBR for oil‑resistant engine‑bay parts; EPDM for wiring‑harness insulation; flame‑retardant modified EPDM & silicone rubber for NEV battery‑system parts. Full material specification documents were issued and confirmed by the client before formal development.

2. Tooling Design & Prototype Sampling

Our in‑house tooling workshop designed and manufactured multiple precision compression‑molding & injection‑molding dies. Following IATF 16949 APQP procedures, prototype samples were produced for customer fit‑and‑assembly evaluation.

3. Full‑scale Reliability Validation (CNAS‑accredited Lab)

Comprehensive lab tests were performed at KINGTOM CNAS‑accredited testing center: thermal shock cycling, ozone ageing, compression‑set measurement, air‑tightness & waterproof test, oil immersion, vibration durability etc. Complete test reports were generated. Samples were iteratively optimized whenever sealing or dimensional risks were identified.

4. PPAP Submission & Pilot Run

After sample validation passed, full PPAP documentation package was submitted. Pilot serial runs were carried out to verify assembly performance, dimensional consistency and process stability; process parameters were fine‑tuned based on client feedback.

5. Mass‑Production Delivery

Once pilot production was fully approved, full‑volume manufacturing was launched with strict in‑process quality control, achieving stable delivery and maintaining automotive‑grade low PPM failure rates.

Project Outcomes & Customer Value

• Dozens of rubber parts across four product families obtained full customer approval and were released for multiple ICE & NEV vehicle platforms. Lamp‑assembly parts effectively eliminated fogging and water ingress; wiring‑harness grommets delivered consistent waterproof‑insulation performance for vehicle body penetration points; engine rubber components endured harsh under‑hood conditions; NEV parts satisfied battery‑pack sealing and flame‑retardant design requirements.

• The whole project strictly followed IATF16949 quality‑management procedures with traceable complete PPAP documentation. Most reliability tests were completed in‑house at our CNAS‑accredited lab, shortening overall project timeline and reducing customer third‑party testing expenses.

• One‑stop development & delivery for diversified components freed the client from managing multiple vendors. Tooling, compounding, testing and mass‑production are all completed internally for better lead‑time and cost control.

• High and stable production yield in serial phase with excellent on‑time delivery rate. KINGTOM keeps supporting customer's subsequent product revisions and new‑project iterations.

Conclusion

Small‑size yet critical, automotive rubber sealing and damping components directly determine long‑term reliability of vehicle electrics, powertrain and NEV e‑power systems. With more than 25‑year accumulation in automotive rubber‑plastic components, KINGTOM undertakes custom projects for lamp systems, engine compartments, wiring harnesses, suspension, NEV e‑powertrain systems and forklift rubber attachments. Please send us your drawings and working‑condition specifications for project cooperation discussion.