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5
4.2 Inspection
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Ball [Fig.4.10]
Measure the outside diameter, and if it is outside the usable
range, replace the ball.
Usable range of ball
NDP-40
Sø1.772 ~ Sø2.028 in
{Sø45.0 ~ Sø51.5 mm}
NDP-50
Sø2.232 ~ Sø2.555 in
{Sø56.7 ~ Sø64.9 mm}
NDP-80
Sø3.189 ~ Sø3.650 in
{Sø81.0 ~ Sø92.7 mm}
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Valve seat [Fig.4.11]
Measure the dimension shown at left, and if it is outside the
usable range, replace the seat.
Usable range of valve seat
B_C, B_N, B_E
B_V, B_H, B_S
B_T
NDP-40
0.181 ~ 0.453 in
{4.6 ~ 11.5 mm}
0.067 ~ 0.165 in
{1.7 ~ 4.2 mm}
NDP-50
0.197 ~ 0.492 in
{5.0 ~ 12.5 mm}
NDP-80
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O ring (other than PTFE)
If O ring is worn out or cracked, replace it.
4.3 Installation
For installation, see [Exploded View] on the separate sheet and install in the reverse order of disassembly.
Tightening torque for manifold retainer bolts
BA_, BS_
BP_, BV_
NDP-40
18 ft-Ibf {25 N-m}
15 ft-Ibf {20 N-m}
NDP-50
18 ft-Ibf {25 N-m}
NDP-80
<NOTE>
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Make sure there is no dust on the seal surface and the seal is
not damaged.
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Replace the PTFE O ring regardless of its condition.
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Match the convex and concave parts of the protector. [Fig.4.12]
(NDP-50 BP_·BV_, NDP-80 BP_)