SELVA MARINE Kingfish 25, Руководство по обслуживанию

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2-16
2
Tilt up operation
When the up side of the PTT switch is pushed, fluid pressure created by the gear pump
2
causes
PTT fluid to flow into the up side of the shuttle piston
c
and pushes the up valve
a
, causing it to
open. At this point, the fluid pressure forces the shuttle piston
c
to slide to the down valve
b
. The
protrusion on the shuttle piston
c
opens the down valve
b
, which opens the return passage. Then,
the PTT fluid flows into the lower chamber of the cylinder to force the free piston
0
and the tilt ram
assembly
A
to move up.
The relief valve
3
of the fluid pressure passage will open when the fluid pressure is more than the
limit, while the relief valve
3
in the upstream will not operate in the trim range because the passage
is blocked with the free piston rubber seal
g
. The up-relief valve opens at 3.6 MPa (36.0 kgf/cm
2
,
522.0 psi)
.
h
Fluid pressure passage
k
Return passage
m
Relief passage
È
F25
É
FT25
È
3
3
É
g
0
A
c
a
b
2
h
k
m
PTT unit