One of thirty three “transfer” mould tools with multiple configuration changes.
A top tier medical device OEM had made a number of acquisitions, and as a result, an existing network of suppliers was inherited, and also number of dissatisfied customers. In short time, an executive decision was made to withdraw tooling from one supplier that was non-ISO, unable to satisfy quality requirements, and frequently late on deliveries. In addition, the existing supplier employed lax systems for documentation, control of spares, and change-over’s from one moulded part configuration to another were dependent on “tribal knowledge”.
* To relocate approximately 33 mould tools that could best be characterised as low volume, high maintenance and labor intensive.
* To balance (raw material) inventory needs to satisfy demand, and build a “buffer stock” to allow for down-time (transport, process development, maintenance and refurbishment, re-qualification).
The entire programme to relocate the tooling to a new supplier and be in a qualified “production ready state” was earmarked for completion in six months.
Project lead (Tooling Engineer), Purchasing Manager (OEM), Product line process Engineer (OEM).
Later stages engaged project team at incumbent supplier consisting of project manager, moulding process engineer, tool room manager, quality manager.
A comprehensive tooling audit and evaluation was conducted at the outgoing supplier, capturing hardware specifics, press information, peripheral equipment, measuring techniques etc, and a thorough understanding of “current tool condition”.
Financial resources would be needed to refurbish tooling, and build an inventory of spares.
Priorities were set in line with demand (forecast), and a time-line was established that would facilitate three mould tools every other week to be shipped to the incumbent supplier.
Advance “retain samples” were shipped to the new supplier for evaluation and metrology assessment.
A consensus was reached that building a “buffer stock” of raw material (plastic components) would allow time for the tools to be taken out of service for repairs and refurbishment as necessary.
A tooling “pack and ship” protocol was developed and shared with the team.
A re-qualification plan was developed based on capturing three critical to quality (CTQ) dimensions from five samples of each part. Full validation was deemed redundant in light of the tooling being closer to the end of it’s tool-life than the beginning. Additionally, the moulded part was not regulated.
Weekly conference calls were scheduled to review status, address concerns and problems, and anticipate potential issues with the next batch of tools.
Process trials were scheduled at the incumbent supplier.
Upon receipt of each batch of three mould tools, the incumbent supplier took photographs of everything received, noting any anomalies.
Tools were bench evaluated. Repairs / modifications were initiated. Change-over configurations were registered. Spares were inventoried.
Process trials were initiated, with the assumption that any process data shipped with the tooling was likely unreliable, (many tools were not capable of producing acceptable parts at a nominal process).
Critical to quality measurements were captured on five samples, and compared to metrology data. First article inspections were completed , with non-conformances* highlighted and submitted for review to (OEM) project team for review.
First sample parts were received by the customer(OEM), and released with a similar quantity of samples from buffer stock for manufacturing assembly and functional testing. This provided an “apples to apples” comparison analysis, and a pass / fail benchmark. First sample parts that failed functional testing were evaluated for failure mode, and addressed with the moulding supplier, typically requiring a moulding process tweak or minor tool modification to correct the issue.
*Original design intent was not always available, however, as a non-regulated component of the end product, assumptions could be made as to design intent, and documented in the form of drawing notations.
A “blanket” PO was initiated to cover the costs associated with mould tool repairs.
Reconciliation / Project close:
All mould tooling was restored to good running order.
All recorded non-conformances were resolved. This was achieved primarily by mould repair. In some instances where mould repair was not possible, a review of the specifications for mating components, (fit, form and function), tolerances could be expanded or shifted to facilitate, thus making the part compliant.
All changes were submitted through engineering change control process, resulting in either a new drawing or revised specification.
Raw material part acceptance forms were submitted by the supplier for approval, and signed off.
With capable tooling, accurate drawings and specifications, and elimination of deviations and waivers, the new supplier was in a strong position to supply reliable product, below customer (OEM) AQL of 3%.
Tribal knowledge was largely eliminated with the initiation of a mould tool history file, chronicling all defects, performance attributes, and mould changes.
“Dock to Stock” status was achieved after 3 consecutive shipments below the 3% AQL.
The “staggered” system of shipping three moulds per week was successful, and the goal of all tools being relocated and qualified within six months was achieved.
About the author: Paul Mulville is the owner of Tooling Transfers, a tooling services company based in Maine, USA. He is a graduate of Carshalton College, Surrey, England. His career has encompassed toolmaker, tooling manager, tooling engineer, and global project management (India and China), he has worked both sides of the fence, for custom and captive moulders, and also for Giant OEM companies, serving medical device, consumer goods, electronics and automotive.