Hydraulics - Seafish

96
SAQ4
There are quite a numberof things you can list in this answer,
but you should first have looked for 'slow movement in Table 8
on page 89. It gives you four possible causes:
• Oil viscosity too high
• Insufficient lubrication
• Sticking servo valve
• Worn component
But it also tells you to look under 'low;flow' on page 87 where
you are given another eight possible causes, one of which,
namely, 'worn component', has already been listed. So, there
are eleven possible causes which you should have listed.
SAQ5
The 3 main sources of contamination are:
(a)
(b)
(c)
Contaminants in the replacement oil.
From the atmosphere through seals and from the surfaces
of cylinder rods, and through the breather on the tank.
From the wearing of components in the system.
Seafish Open Learning