From single-source risk to reliable dual sourcing for an A356 pump housing program
A European Tier-1 automotive supplier needed a qualified second source for a leak-sensitive aluminum pump housing program. Bohua supported DFM review, free sampling, PPAP validation, pilot production, and scale-up into a stable dual-source supply model.
Program snapshot
Component: Water pump housing
Alloy: A356 aluminum
Volume: 180,000 pcs/year across three variants
Critical requirement: ±0.1 mm features and 100% leak testing
The challenge
A buyer problem that goes beyond simple pricing pressure
The customer was exposed to single-point failure risk. If its only supplier faced capacity, quality, or logistics disruption, the pump housing program could stall. Cost increases were also compounding because the procurement team had limited leverage without a qualified alternative.
The solution
A structured qualification path that reduced risk at each stage
Phase 1
Free sampling and DFM review
Bohua reviewed the existing design, improved metal flow with rib changes, reduced unnecessary mass, and proposed tooling adjustments that removed a secondary machining step.
Phase 2
PPAP documentation and validation
The program moved through dimensional reports, material certifications, PFMEA, control plans, MSA, and a 300-piece trial run with English documentation and traceability.
Phase 3
Pilot production ramp
Both teams used a staged monthly ramp from 5,000 pieces to 30,000 pieces so logistics, quality checkpoints, and scheduling could stabilize before larger allocation.
Phase 4
Full second-source qualification
After six months of stable pilot output, Bohua was approved as a qualified second source and awarded 40% of annual volume with room to expand.
The results
Measured gains across cost, quality, and supply resilience
22%
cost reduction per piece
0 PPM
customer defects over 18 months
12 → 8 weeks
lead-time improvement
150,000+
pieces delivered
What changed commercially
Weight optimization, tooling improvements, and dual-source leverage drove a 22% piece-price reduction while also improving purchasing flexibility.
What changed operationally
Lead time dropped from 12 weeks to 8 weeks, defect performance stayed at 0 PPM, and the customer gained a practical hedge against single-supplier disruption.
Key takeaways
Why this program worked
Who this page is for
OEM buyers qualifying a new aluminum casting supplier
If you are managing a pump housing, valve body, gearbox housing, or other leak-sensitive aluminum component, the second-source decision is not just about cost. It is about engineering discipline, documentation quality, and launch control.
Bohua supports programs that need DFM review, sampling, PPAP readiness, machining coordination, and export-oriented communication.
Recommended next step
Send the current drawing set, alloy target, annual volume, and critical dimensions. A serious supplier review starts with manufacturability, not just a quoted number.
Ready to evaluate your next project?
Contact us for a free DFM review
If you are looking for a second source for aluminum castings or want to benchmark a current supplier, Bohua can review your part and quotation inputs.