It was particularly hard to disassemble the engine piston since most components are made to fit and are not made for repeated assemblies and disassemblies. As a result the piston was taken apart as much as was possible.
Connecting Rod Top
The connecting rod, after drop die forging is cracked at the top. It is made of Steel AISI 4340.
Connecting Rod Lower
The lower connecting rod' top side is visible in the photo. The lower end of the connecting rod could not be dislodged due to the piston bolt present but the geometry can be viewed in the CAD model here. It is made of Steel AISI 4340 by drop die forging.
Hex Bolts (Partially Threaded)
The threads on the hex bolts are visible in this picture. These are used to hold the lower and top connecting rods together along with the bolts. This is made up of Stainless Steel.
The piston head is made through stock machining of Aluminum 2618 T6. It is made for high temperature resistance since it is the part of the piston which comes in contact with the air-fuel. The extruded sides of the piston head stops the connecting rod from striking the head during high Rpms.
The Hex nuts are made from stainless steel and are ideally purchased. They help constrain the hex bolts and stop the lower and top ends of the connecting rods from moving.
Bill of Materials with Design for Assembly
After disassembly a detailed Bill of Materials was prepared. Functionality of each part was analysed and areas of optimization were analysed through the design for assembly process.
A possible area of improvement was identified to be the piston head and the extrusions. There were three concept sketches prepared with different side geometries of the piston heads.
Iterations to Improve recyclability and Pugh Matrix
Three Improvements for recycling:
Have recycling markers embedded onto the top portions of the piston heads for Aluminum Recycling as well as markers on the connecting rods embedded for steel recycling as is present on Apple products.
Make a standardized piston for most engines by the same manufacturer and reuse them from older cars in newer cars. Offer rebates and discounts for every piston/engine block that is returned.
Nuts and bolts are the most wasted resource in terms of machine parts and are an essential part of manufacturing. Have collection points for the nuts and bolts, so they can be recycled more effectively.
Have more engine reworking spots where professionals could rework certain engine parts. Similar setups exist for marine diesel engines where the two stroke engine components are reworked and sent back to the ship owners.
The main improvements identified were in the extrusion on the piston head that is used to contain the connecting rod. On the basis of the amount of material used to make the piston head, version 1 was deemed the appropriate approach.