Conceptual Design Review

GT Technologies

• Assemble valve train components • Receive hundreds of parts from suppliers in five different continents • Contracts with Ford, Chrysler, John Deere, Volkswagen, Harley Davidson… • $100 million in business

GT Technologies

• Products include: – Roller finger followers – Rocker arm assemblies – Roller lifters – Lash adjustors – Cam follower rollers – Other Precision Stamped or Machined Components

Hydraulic lash adjustor

• Present in many modern IC engines • Reduce noise during cold start-up • Maintains zero valve clearance during thermal expansion of the valves • Eliminates the need for periodic valve clearance adjustment • Uses engine oil to supply pressure

Problem with HLA

• A small ball bearing valve in each HLA controls oil flow • Fit between check ball and valve seat is critical • Debris in oil, poor seat polish quality, extended periods of non use and incorrect engine oil viscosity all hurt performance

Polishing Process

• Diamond cut #9 fine grit ruby polishing stone • Spring supplies fixed pressure to polishing arm • Polishing stone comes in at an angle • Spherical seat created • Stone replaced every 500 parts polished • Oil based lubricant/coolant used • About 24 parts per minute polished per machine

Problem with Polishing

• Grinding vs. Polishing • Money spent on polishing stones • Loss of productivity • Is it even necessary?

Improvements to Polishing • Spring polish pressure • Machine RPMs • Length of polishing time • Type of polishing stone material • Lubricant • Angle of polish • Longevity of polishing stone

Quality control

• 2 parts out of 500 • Air check system • Visual check • Rejected products

Problem quality control

• Quantified data • What is a good seal?

• Treatment for non passing products

Improvements to Quality control • Develop a quantitative test system • Do not slow down production • Turn data into useful information

Questions?