1. Maintenance

2. diagram only not to scale
Maintenance
the generator units are not normally manned and are remotely controlled
each group of rotor units could be fitted with a current sheltered dock for workboats
a helideck on each group will permit rapid evacuation of a casualty
Stroma 3
security considerations may prefer inspection and maintenance access
to be by helicopter only with no access being made available from the sea
© clf anderson
diagram only not to scale

3. Maintenance access roadways are installed during final commissioning
Stroma 3
access roadways are installed
during final commissioning
equipment such as a mobile crane and
HP water jetting equipment could be held
on each group of generator units as required
© clf anderson
diagram only
not to scale

4. diagram only not to scale
Maintenance
trash screens are self cleaning when the current changes direction
Note: screen bars run
horizontally not vertically
as shown in this diagram
the screens prevent access to the rotor by cetaceans, pinipeds and large fish
each screen is designed to be easily lifted from its slot mounting and replaced
inspection of underwater parts can be by ROVs (remotely operated vehicles)
shellfish accretions can be removed using high pressure water jetting robots
© clf anderson
diagram only not to scale

5. © clf anderson diagram only not to scale
Maintenance
isolation
gates open
isolation
gates closed
conventional canal lock gates may be used
isolation gates are moved at slack tide to allow maintenance on the rotor and the drive
these gates would be kept closed until the unit is in place and fully commissioned
power would then be immediately available to produce revenue
© clf anderson diagram only not to scale

6. © clf anderson diagram only not to scale
Maintenance
isolation
gates open
gates may be made
adjustable to control
the entry flow
isolation
gates closed
gate
disk base
top bearing
high pressure water is pumped down the gate spindle to flush out
grit and to lift the gate to allow it to be turned during slack tide
reaction jets at the blade tips may be used to turn each gate
floor of guide chamber
these are the only underwater bearings in the whole device
automatic gates can be used to close off the bypass channels
© clf anderson diagram only not to scale

7. © clf anderson diagram only not to scale
Maintenance
this unit is in operation
this unit is fully isolated
if required, the isolation gates can be fully sealed using water bags to allow
the water level in the guide chamber to lowered for extensive maintenance
the water bags would be retained in place regardless of the state of the tide
© clf anderson diagram only not to scale

8. © clf anderson diagram only not to scale
Maintenance
flow guides
water-filled bags
water bags alone may be used to isolate the rotor chamber thus saving costs
© clf anderson diagram only not to scale

9. © clf anderson diagram only not to scale
Maintenance
the chamber may be provided with guide slots in the sides of the water passages
isolation gates may simply be lowered into place when isolation is required
high pressure water jets at the bottom edges of each gate will clear shellfish
and weed from the guidance slots as it is lowered into place
conventional canal lock gates may also be used
© clf anderson diagram only not to scale