Hydraulic pump failures may be related to hardware or problem in oil. In this study, the excavator hydraulic pump failures were investigated by using visual observed and measuring the part component. The disassembled process of the pump was performed considering the manual part book of the excavator hydraulic pump. The abrasive wear on the pump slipper and swash plate was observed by comparing the guidelines for the reusable part. The value of more than 1.07 mm clearance within piston and cylinder bore was measured then the results over the allowable limit considering the manual part book. Properly analyzing of component failure can provide valuable information about what caused the failure and thus can be to avoiding future unscheduled downtime.

Rack grate is a component composed of rack clip and rack bone arrangement that serves as a dropping cross-section media of coal and as a media of coal burned in the boiler.  As part of the main component, the rack grate can be regarded as one of the components that ensure the success of combustion in the boiler. Failure to this component will certainly interfere with the implementation of boiler operations. In addition to require the boiler to be shut down while repaired, in addition to requiring the boiler to be extinguished during repairs, the inoperability of the boiler makes the steam production process at the PLTU impossible and ultimately the electricity generation process cannot be carried out as usual. Damage to the rack grate component has a type of plastic deformation with variable loads and fluctuating heat, which means that the thermal stress in the system has reached the yield stress point. To find out the root cause of this component damage quickly and accurately, an analysis of the results of the implementation of engineering software in this case Ansys Workbench, and a comparison of actual operating data, and data design is the best choice. Lastly, by evaluating the optimum values of temperature, equivalent stress and strain, total deformation, input process parameters value can be controlled to the desired values, resulting in less stress concentration occurs, so that the damage to the workpiece can be reduced or even eliminated.

Mesin penggerak conveyor terdiri dari motor, gearbox, serta conveyor sebagai alatmemindahkan lumpur dengan motor 2,2 KW putaran 1400 rpm. Rangsangan gaya luarmenyebabkan terjadinya getaran paksa jika rangsangan tersebut berosilasi maka sistemdipaksa bergetar pada frekuensi ransangan. Penelitian memfokuskan pada analisa getaran padabagian block mesin yaitu Seal input gearbox, Gear input dan Seal Output gearbox searahhorizontal dengan mengukur kecepatan getaran dan temperatur yang dihasilkan. Getaran pada daerah3 yaitu seal output gearbox mengalami peningkatan 4,95 mm/s yang tidak stabil sehingga diprediksibahwa elemen tersebut getarannya tidak stabil dibandingkan gear input dan seal ouput gearboxsehingga perlu adanya perbaikan lebih lanjut. Daerah 2 yaitu gear input mengalami peningkatantemperatur 53,6 0C dibanding daerah 1 dan 3 tetapi elemen tersebut masih dalam kondisi stabil.Getaran terjadi pada elemen mesin berbeda beda pada setiap priode waktu serta temperatur kerjasetiap elemen mesin juga mengalami perubahan setiap priode waktu.