ANALISA KEGAGALAN RODA GIGI LURUS (SPUR GEAR) PADA MESIN KEMPA (SCREW PRESS) DAN PENCEGAHANNYA

Abstract

One unit of screw press machine at mills (PKS) PTPN V Sungi Galuh, Kampar, Riau damaged spur gear during operation of 250 hours of work. After the replacementof parts (reactive maintenance) a pair of spur gear drive worm screw press. Damage occurs in gear uneven portion on the surface of the tooth. In this study used several hypotheses, examination and testing of samples of the test object, among others: (1) Observation and study of literature, (2) visual examination, (3) Mode of gear failure diagram, (4) Preparation of fish bone diagram (5) Testing violence, (6) Test of chemical composition, (7) Test metallography, (8) fraktografi test. The observation of the fracture surface spur gear (tooth fracture) identify the occurrence of damage overload (overload breakage) shown by the fracture surface in the form of a smooth, flat-lined, looks blurry and deformed (deformation) at fault spur gear while chevron mark on the fracture surface is not clearly visible, which looks just like the line - fault lines are layered irregular. At the micro structure pembentukaan adannya spur gear is not visible signs of damage caused by the increase in operating temperature or the formation of destructive patterns in the structure. Damage in the form of overload breakage caused because the mechanical properties test results spur gear with an average hardness BHN 102.73 with a tensile strength of 35.93 kg / mm² literature under the mechanical strength of the manufacturing material for machining gears with hardness 123-183 BHN for tensile strength 45 kg / mm². While damage to the slant-shaped portion of the head caused by a pair of axles tooth spur gear drive worm screw press is no longer in the position of the centerline. This damage begins with the destruction of the bearing axle spur gear drive worm screw press.