LEAFLET Extra long service life UWC Cutter Blade Laboratory test results Several cutter blade materials are developed to meet demands on UWC（Underwater Cutting） pelletizing system. The most suited cutter blade material is selected to achieve customer’s individual needs for high cutting performance and wear resistance. JSW developed "JSW-HA", a cutter blade material that can be applied with a wide variety of polymers and maintain stable pelletizing through a long period. Features ■ Long service life Compared with conventional blade material, the friction coefficient with the die surface is low. As a result, the abrasion resistance is improved so that the service life is extended 2 times longer than conventional one. The Japan Steel Works, Ltd. Plastics Machinery Business Division Fig.1 Transition curve of relative coefficient of friction (vs standard die plate surface material) The friction coefficient of each materials during the pin on disk wear test is JSW-T>JSW-HA, which means that JSW-HA has better compatibility with the die plate. The uniform contact with the die plate can be achieved in a short grinding time at operation. ■ Extensive usage environment Since both abrasion resistance and corrosion resistance are excellent, it can be used in corrosive environments where JSW-Y (conventional wear resistant material) was not suitable. ■ Maintaining sharp edge Sharp edges are kept for a long time because JSW-HA has reasonable self-sharpening property. Advantages ■ Lower running cost Running cost of both the cutter blade and the die plate can be lowered by extending their service lives by the excellent compatibility with the die plate hard layer. Because of the extended service life of blades, the frequency of stopping the extruder for replacing blades can be decreased. It allows to reduce production loss, replacing work and starting and stopping cost. Fig.3 Pin on disc abrasive wear test results In case of JSW-Y, because of its high wear resistance, self-sharpening property is relatively low, and sharpness may be decreased gradually. In JSW-HA, the hardness is set smaller than JSW-Y so that the self-sharpening property is maintained for a long time. According to the wear test result, JSW-HA has about 5 times smaller wear volume than JSW-T; conventional standard material. It means JSW-HA allows to extend the service life dramatically. ■ Decrease of loss amount Since the sharp blade edge is kept for a long time, cutting troubles caused by the blunted blade edge are hardly occur. Fig.5 Performance map of blade material Japan Steel Works, Ltd. Tokyo Head Office Gate City Osaki West Tower 1-11-1, Osaki, Shinagawa-ku, Tokyo 141-0032, Japan Fig.4 Water immersion test results (Ionized water 25 ℃ , 7 days) Europe (Germany) JSW-HA has corrosion resistance equal to or h i g h e r t h a n J S W - T. Therefore JSW-HA is also applicable in the environment where JSW-Y may corrode. China (Shanghai)