6
■
FP
□
, FV
□
, FDT types
▪
Remove the flat valve and valve seat
(see [ 4.1 Removal FP
□
, FV
□
, FDT types] on P.3).
▪
Remove the 8 (12 on the NDP-15) retainer nuts from the
out chamber, and remove the out chamber. [Fig.5.4]
▪
Remove the center disk using the cap and
disk remover.
(special tool: Part No. 771132). (NDP-5) [Fig.5.5]
▪
Remove the center disk from one side.(NDP-15) [Fig.5.5]
▪
After the center disk (outside) has been removed, remove
the diaphragm and the center disk (inside).
▪
Remove the center disk and center rod from the opposite
side of the main body.
<NOTE>
▪
When the diaphragms are removed, the main body is
separated 2 pieces. For easy work, leave bolts fastened
temporarily before remove the diaphragms.
▪
Fix a double nut to one end of the center rod and take
the diaphragm and center disk off the opposite end.
[Fig.5.6]
▪
Be careful not to scratch or score the center rod.
5.2 Inspection
▪
Diaphragm
If the diaphragm is worn out or damaged, replace it.
New replace just one diaphragm.
Guideline of diaphragm life
NDP-5
PTFE 30,000,000
cycle
CR, NBR, PTFE
10,000,000 cycle
NDP-15
TPEE, TPO
15,000,000 cycle
▪
Center rod [Fig.5.7]
Measure the diameter, and if it is outside the usable range,
replace the rod.
Usable range of center rod
NDP-5
Ø
9.95 ~
Ø
10.0 mm
NDP-15
Ø
13.96 ~
Ø
14.0 mm
