Environmentally Conscious Design & Manufacturing

1. Environmentally Conscious Design & Manufacturing Class20: Remanufacturing Prof. S. M. Pandit

2. Why Remanufacture? New Remanufactured (40% less) Cost Reused Potential Performance & reliability loss

3. Why Remanufacture ? • E.g. - Cartridge remanufacturing saves 38,000 tons of metal & plastics annually • 18 million gallons of oil needed annually to make cartridges • Encourages local small business • 1000 years needed for plastics to decompose

4. Bearing Remanufacture - 1

5. Bearing Remanufacture - 2 WEAR LIFE vs. FATIGUE LIFE The estimated service life of ball and roller bearings is based upon metal fatigue. Few bearings reach full life expectancy but are retired early because of wear, not fatigue. One recent investigation of 50,000bearings removed from service revealed that less than 10% were scrapped because of fatigue failure.

6. Rated average fatigue life = 80,000 hours. By the time they had averaged 22,000 hours in service, the internal clearance had increased an average of 0.10" and the bearings could no longer perform smoothly. Bearing Remanufacture - 3

7. YOU SAVE ABOUT 40-50% Worn bearings are restored to original prime condition-with performance guaranteed-for about 50% to 60% of the cost of new bearings of the same size and rating. Bearing Remanufacture - 4

8. Remanufacturing Processes Multi - stage remanufacturing process for engines

9. Example - 1 • Step 1 • Engines are stripped bare. • The block is baked for eight hours in a thermal oven at 700 degrees. • Naturally cooled, then steel shot for ten minutes. • The block is then magnafluxed and carefully inspected for flaws.

10. Example - 2 • Step 2 • The block is align honed • to insure the crankshaft main journals are on the same centerline; • this reduces bearing wear and improves oil pressure and performance. • Cylinders are then bored to specification and honed.

11. Example - 3 • The block deck surfaces are checked in reference to the crankshaft centerline. • The block then goes through a high pressure wash to clean all galley holes followed by the application of several coats of rust protectant after deburring and tapping. • New plugs and a set of cam bearings are installed.

12. Example - 4 • Step 3 • The crankshaft is precision ground, and oil holes are chamfered, micro polished, and rebalanced. • Shafts that won't grind to size arc discarded. • Connecting rods are resized and balanced, pistons are precision fitted to connecting rods, and assemblies are weighed and checked for balance.

13. Example - 5 • Step 4 • The block receives three coats of high temperature engine paint. • All bolts are heat treated, stress relieved, deburred, and hand inspected. • All external parts are inspected, painted, and brought to the clean room for final check out and final assembly.

14. Example - 6 • Step 5 • Cylinder head castings are remanufactured to exact specifications. • All heads receive hard seats for unleaded or regular fuel. • Valve seats are triple angle cut, and valve guides are replaced or resized. • Valves are refaced or replaced as required.

15. Example - 7 • The head surface is milled to ensure a perfect mating surface. • All valve heights are measured and adjusted. • Each spring is pressure tested and each combustion chamber is vacuum tested. • Every bolt hole is tapped. Cylinder heads receive three coats of high temperature paint.

16. Example - 8 • Step 6 (Blue print and final assembly) • Each bore is checked with a precision dial bore gauge. • Lifter bores are checked for size and correct clearance. • Each lifter bore is polished with flap wheels • to assure smooth lifter rotation.

17. Example - 9 • Each piston ring is checked in bore for proper end gap. • Crank and main bearings are installed in block and bearing clearances are checked. • Camshaft is installed in block and checked for proper clearance. • Timing chain and sprockets are installed, and camshaft degree is checked. Pistons and rod assemblies are installed in bores.

18. Example - 10 • Each rod is checked for correct clearances. Crankshaft thrust end play is checked and centered. • Cylinder heads are installed and torqued to block. • Lifters are installed and clearance checked. • New pushrods are installed.

19. Example - 11 • All valves are adjusted perfectly to obtain optimum lifter preload. • All cylinders are vacuum tested. • Complete oiling system is pressure tested to ensure all internal clearances are perfect.

20. Example - 12 • Step 7 • Dyna testing. Every engine is installed in a dyna testing machine. Engine is tested for • Internal oil pressure • The ability to hold pressure without leaking out internally; • Oil pressure and volume running at 1000 RPM.

21. Example - 13 • Each cylinder is checked for instant compression and leak down. • Engine is load tested to ensure there are no tight spots. • Engine is visually inspected for any external oil leaks and smoothness of operation.

23. Quick Facts - 1 • 53 billion dollar industry • There are over 73,000 firms in the U.S. • Automotive remanufacturing is a 36.5 billion dollar industry • 46% of the parts on today’s automobile are available as remanufactured units

24. Quick Facts - 2 • Automotive remanufacturing recycles 80% of the energy and 85% of the materials. • Automotive remanufacturing reduces emissions

25. References • http://www.laser-service.com • http://www.cardone.com/products/articles.htm