Comparison of PK, POM, POM TF and PA 6.6
Compounder AKRO-PLASTIC GmbH from Niederzissen, in the Rhineland-Palatinate region of Germany, is a producer of aliphatic polyketone compounds which boast outstanding mechanical properties. Excellent wear breakage, very good chemical resistance, toughness on impact loading and an extremely high abrasion resistance are characteristic properties of these products, making them the ideal material for drive components from Zipperle Antriebstechnik, a company based in Renningen, Germany.
The property profile of polyketone allowed Zipperle Antriebstechnik to add to its product range an additional series of highly wear-resistant gears for the machine building and precision mechanics industries. Standard and customer parts are made with extremely high accuracy in various geometries. To complete its product portfolio, the company has opted to manufacture drive components from AKROTEK® PK, an aliphatic polyketone from AKRO-PLASTIC. Polyamides (PA) and polyacetal (POM) are currently the established materials for thermoplastic gears.
The addition of AKROTEK® PK provides a gear material which demonstrates advantages over PA and POM, thereby expanding the list of potential applications for various gears. Cylindrical gears and bevel gears made of polyketone have meanwhile been added to the product lineup and have already undergone extensive testing by Hans Zipperle Antriebstechnik on test rigs developed in-house. This included wear testing conducted on similar gear pairs using a bevel gear system. The tests demonstrated that the service life of AKROTEK® PK bevel gears can be extended significantly (see Tab. 1).
Whereas POM and PA bevel gears show extreme signs of wear, polyketone bevel gears remained virtually wear-free following the same test period (see Figures 5-7), thereby increasing the useful life of the gearboxes and decreasing downtime for repair and maintenance work. As Hans Zipperle sums it up, “Polyketone has become our go-to material for use in the gear sector and provides a superb alternative in our material profile.”
»The particularly favourable mechanical properties make this new material extremely interesting for our products. Its exceptionally high abrasion resistance and very good tribological properties make gears manufactured of polyketone suitable for significantly higher power transmissions than the gear materials typically used«
Hans Zipperle, Managing Director of Zipperle Antriebstechnik
Bevel gears following comparison loading on POM and PA 6.6, tip abrasion and tooth breakage