DIAbide Inserts

for Machining Non-Metallic Materials

and Non-ferrous Metals

Applications

Turning graphite rotating seal wear parts A seal manufacturer uses sp³ TPG-322 inserts to turn graphite rings at 2500 rpm, .003 to .0085 ipr feed, and .250" DOC. No coolant is used. The required surface finish is 32 Ra. The sp³ inserts machine 2700 parts per edge for a cost per part of $.02, compared with 1200 parts per edge and per-part cost of $.06 for a competitive diamond-coated insert.
Turning abrasive carbon sp³ CVD diamond inserts show superior performance in turning applications of abrasive carbon. In one application a TPG-322 insert is used to turn a 5" diameter part at 2500 rpm (3270 sfm), .0035 fpr feed, and .250" DOC. The sp³ tool cuts 840 parts per edge vs. 96 parts per edge for a ceramic insert and 3 parts per edge for C2 carbide. Also, the operator does not have to continually check size because of the sp³ insert's superior wear resistance. In addition to reducing cutting cost per part—$.02 for sp³ vs. $.04 for ceramic and $.20 for carbide—scrap is virtually eliminated. Another application uses an sp³ TPG-322 insert to turn a 4" diameter part at 1500 rpm (1570 sfm), .0035 fpr feed and .300" DOC. The sp³ insert cuts 83 parts per edge vs. 12 parts per edge for a ceramic insert and 2 parts per edge for C2 carbide, with similar cost advantages.
	Grooving respirator components A manufacturer of purifying repirators has chosen to use sp³ inserts to groove graphite epoxy molded compoments because of dramatically increased tool life. The manufacturer was machining 150 parts per edge at 96% yield using carbide tools. Switching to sp³ diamond-coated tools has improved throughput to 3500 parts per edge as well as increasing yield to 99.8%
Turning aluminum castings for appliance motors A manufacturer of appliance parts uses sp³ TPG-321 inserts for turning and boring A383 aluminum castings. Machining parameters are: speed 1800 sfm; feed .004 ipr, DOC .062". A full cutting edge insert is required. No coolant is used , and a good visual finish is expected. The results are 27,000 parts per edge, 81,000 parts per insert for the sp³ tool, vs. 65,000 parts per insert for PCD. Cost for the sp³ TPG-321 insert is $50 for three edges; a full-edge PCD insert costs over $100.
	Turning automotive wheel hubs sp³ inserts are used to dry-turn wheel hubs diecast in 380 aluminum. With the carbide inserts previously used, built-up edge required shutdowns every half-hour to remove the edge from the tool. With sp³ inserts there is no built-up edge problem, plus tool life is 5 times that of the carbide inserts, allowing 25,000 parts to be machined per tool.
Machining aluminum engine parts sp³ inserts are used to machine a critical surface of pistons diecast from 380 (10% silicon) aluminum. Tool life equal to PCD has been demonstrated. The lower cost of CVD diamond inserts saves $4.00 in tooling per 1000 parts. With millions of pistons made per year, the annual cost saving is significant.
	Milling aluminum intake manifolds An automotive parts manufacturer uses sp3 SEC-422 inserts to mill A319 aluminum intake manifolds at 4200 sfm, .007 ipr and .100" DOC. A mist coolant is used, and a good visual finish is required. Wear life of the sp³ CVD diamond insert is 960 parts per edge, 3840 parts per tool, vs. 1000 parts per insert for PCD. Cost per part for sp³ is $.02 vs. $.06 for PCD.
Turning brake rotors The auto industry is introducing rear brake rotors made from metal matrix composite (MMC) materials. MMC brake rotors are 40% of the weight of traditional cast iron rotors, significantly reducing the vehicle's unsprung weight. MMCs are typically an alloy of aluminum and 25% silicon carbide particles, and can be machined only with diamond tools—carbide can't cut MMCs. CVD diamond coated tools are approximately half the cost per tip of PCD tools, providing sigificant savings.