Q1
a) With the aid of a sketch of the hydraulic system explain thefollowing
i) A Reservoir ii) A pump and a prime mover iii) A pressure controland check valve iv) A power circuit which is made of actuators,motors or cylinders. v) Filter
b) List three functions that are performed by a reservoir and thepurpose of baffles in it.
Q2
a) Define the term ‘Filtration’ in a hydraulic system.
b) Explain the difference between a depth and surface type filterand list three kinds of filters with different applications in ahydraulic system.
c) Name the three ratings used to classify hydraulic filters.
d) Explain what is meant by the terms;
i) Viscosity index
ii) Viscosity
iii) Demulsification
Q3
a) What is the procedure for isolating hydraulic machine beforeremoving a component for servicing?
b) State a recommended procedure to use when you are testing ahydraulic line for leaks.
c) List two things you must take into consideration when you areusing a cleaning solvent on hydraulic components.
d) State five contaminants that may be found in hydraulicsystems.
Doc. No.: EXM/F/03 Page No.: 1/1 Issue No.: 1 Last Update: 15/04/08Revision No.: 1 Date: 12/04/06 Author: EC Approved: DAA
Q4
a) Explain the term ‘Accumulator’ in a hydraulic system and itsoperation.
b) List the three different types of Accumulators used in ahydraulic system and explain the purpose of the nitrogen containedin it.
c) Draw the symbols of the following in a hydraulic circuit.
i) Accumulator
ii) Hydraulic pump
iii) Hydraulic motor
vi) Cylinder double acting
v) Ball check valve
Q5
a. State four different types of positive displacement pumps usedin modern hydraulic systems and state the criteria on which a pumpis selected for a system.
b. With a simple sketch describe the principle of operation of agear pump.
