With the aid of a sketch of the hydraulic system explain the following

Q1
a) With the aid of a sketch of the hydraulic system explain the following
i) A Reservoir ii) A pump and a prime mover iii) A pressure control and 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 the purpose of baffles in it.
Q2
a) Define the term ‘Filtration’ in a hydraulic system.
b) Explain the difference between a depth and surface type filter and list three kinds of filters with different applications in a hydraulic 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 before removing a component for servicing?
b) State a recommended procedure to use when you are testing a hydraulic line for leaks.
c) List two things you must take into consideration when you are using a cleaning solvent on hydraulic components.
d) State five contaminants that may be found in hydraulic systems.
Doc. No.: EXM/F/03 Page No.: 1/1 Issue No.: 1 Last Update: 15/04/08 Revision No.: 1 Date: 12/04/06 Author: EC Approved: DAA

Q4
a) Explain the term ‘Accumulator’ in a hydraulic system and its operation.
b) List the three different types of Accumulators used in a hydraulic system and explain the purpose of the nitrogen contained in 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 used in modern hydraulic systems and state the criteria on which a pump is selected for a system.
b. With a simple sketch describe the principle of operation of a gear pump.