Case Studies

Automotive Pedal Bracket Project

Advanced Plastics were awarded the supply contract for an automotive Pedal Bracket Assembly by KSR Automotive Ltd - an industry leader in the design, engineering and manufacture of an array of automotive products, including sensors, electronic throttle controls, adjustable and fixed pedals.

The contract involved the finalisation of the product design to achieve tooling and manufacturing feasibility, the supply and development of production tooling & assembly equipment and the manufacture of serial production parts for the duration of the product lifecycle. The project carried challenging time constraints driven by the requirement for the OEM to perform crash testing utilising production representative parts produced from serial production tooling.

Project Parameters
- 8 week deadline to supply production representative parts from hard tooling for initial crash testing
- Mandatory Level 3 PPAP to TS16949 standards.
- Progress monitored closely by KSR and the OEM’s Purchasing & Tooling team members.

Product Parameters
- Complex geometry with multiple lines of draw.
- The injection moulded parts to be supplied as an assembly consisting of the plastic - bracket fitted with 3 off threaded brass inserts and 9 off sintered metal sleeves.
- Structurally critical part housing the vehicles brake pedal and accelerator pedal module.
- Two variants to suite LHD & RHD vehicles.
- Parts produced from 50% Glass Filled PA6 Material.
- Multiple Critical and Significant Characteristics.

Design Refinement
The 3D CAD models were received in an un-drafted state, draft angles were added paying particular attention to the areas of deep draw to ensure that the part could be successfully ejected from the mould tool.

Thick material sections were identified and eliminated in order to optimise the mould cycle time.
Fillet radii were added to promote material flow during moulding and increase part strength.
The form of the apertures into which the metal inserts are fitted were redesigned to aid the assembly process.

Mold flow analysis was performed to establish the optimum gating position, minimise part distortion, optimise the position of weld lines and predict the position of mould venting.

Mould Tool Design & Manufacture
Detailed mould tool designs were completed in UK in accordance with Advanced Plastics tooling specification.

A ‘Metal Safe’ strategy was employed on all critical characteristics and areas of predicted distortion.
Separate single impression mould tools for LHD and RHD variants were manufactured in China within a 6 week lead time from receipt of finalised tool design to T1 samples.

Initial dimensional adjustments were made within 24 hours enabling sufficiently representative T2 parts to be provided to the customer for vehicle evaluation and crash testing.
All ‘Metal Safe’ adjustments were made following a full ISIR with T3 trials completed within 5 days.

Production Part Approval Process
The completed mould tools were transferred to UK for the final production part approval process (PPAP).

Representative production trial runs were performed with all SC’s & CC’s proven to be process capable to <1.67cpk

A full layout ISIR was produced utilising our in house programmable CMM equipment.
Gauge R&R studies were performed to verify the repeatability and reproducibility of our control methods.

A Customer verified Launch Readiness Review (LRR) was successfully undertaken.
A full level 3 PPAP documentation submission was made to the customer.

Serial Production
The products are produced on a 450t injection moulding machine with robot de-moulding to ensure part protection and equalised cooling, the final assembly operations are performed at the moulding machine on a cellular manufacturing basis.

A Process Failure Mode & Effects Analysis (PFMEA) performed at the Advanced Product Quality Planning (APQP) phase of the project identified the potential failure modes within the manufacturing process driving the use of appropriate controls to reduce the risks to manageable levels and the use of poka-yoke wherever possible.

Production controls include a bespoke assembly and checking fixture to verify the presence of the sintered sleeves and threaded inserts, a checking fixture representative of the body in white (BIW) to verify the true positions of the multiple fixing points, a distortion check to verify the position of the accelerator pedal module mounting face together with our standard SPC based dimensional and attribute checks.

Project Conclusion

The project was successfully delivered On Time, Within Budget and gained PSW approval without amendment.

Advanced Plastics