Nile Valley University
Faculty of Post Graduate Studies
Mechanical Department
Master Degree by Research in Mechanical Engineering
Study of Failure in Hydraulic Systems
(Case study of machinery used in local gold mining)
By
Salih Adam Burma

ACKNOWLEDGMENT
A journey is easier when you travel together. This project is the result of one year of work whereby I have been accompanied and supported by many people. It is a pleasant aspect that now I have opportunity to express my gratitude for all of them. I would like to express my deep gratitude to my supervisor assistant professor Osama Elmardi , for supporting the subject matter when introduced to him, for his encouragement and belief in me, for the uncountable number of hours spent sharing his knowledge and discussing various ideas, and for many useful comments and suggestions while examining my work. I would also like to express my thanks to faculty members of Mechanical Engineering Department and post graduate studies, who contributed a lot in completing and helping to finish this work in time.
I dedicated my work to my parents, and family members for their continual support and encouragement in attaining my academic achievements. Of all above, i would like to thank God almighty for having blessed me to carry out my research.

Abstract
This project describes different case studies of hydraulic failure in gold mining machines, the research was conducted to know and understand the components, construction, location, function, circuit diagram and the case studies of different failures in the hydraulic systems.
The case study includes all mobile machines that are used in the gold mining site which they have different types, sizes and applications. Hydraulic system consists of a prime mover engine or electrical motor to help in driving the hydraulic pump which draws the hydraulic oil from the reservoir via filter in the suction line and delivers it to the direction control valve via relief valve in the delivery line. Work is done smoothly by converting mechanical energy into hydraulic energy and then back to mechanical energy which is used to move the hydraulic cylinder linearly or rotate the hydraulic motor. Most problems of hydraulic failure in gold mining machines on field site are caused by either contamination or climate condition (temperature). Also usage of old and outdated of machines and lack of maintenance are other factors affecting the machines performance. These problems lead to increase the down time and decrease the productivity.