VACUUBRAND PC 3012 VARIO plastic housing - Manual (Page 106)

page 106 of 129
➨
Position new diaphragm (F) between dia-
phragm clamping disc with square head
screw (G) and diaphragm support disc (E).
+
Note: Position diaphragm with pale side
towards diaphragm clamping disc (facing
pump chamber).
+
Make sure that the square head screw of the diaphragm clamping disc
is correctly seated in the guide hole of the diaphragm support disc.
➨
Lift the diaphragm at the side. Place the diaphragm carefully together
with diaphragm clamping disc and diaphragm support disc in the dia-
phragm key.
+
Avoid damage of the diaphragm: Do not excessively bend or crease
the diaphragm.
➨
Check for washers (D) between the diaphragm support disc (E) and
the connecting rod (B). Do not mix the washers from the different pump
heads, since these are set at the factory to ensure proper pump per-
formance. Make sure that the original number is reassembled at the
individual pump head.
+
Too few washers: The pump will not attain vacuum specification. Too
many washers: Diaphragm clamping disc will hit head cover, causing
noisy operation and possibly causing the pump to seize up.
+
If the old diaphragm is difficult to separate from the diaphragm support
disc, immerse assembly in naphtha or petroleum ether. Do not inhale
vapors!
G
E
F
+
Assemble the original number of washers
(D) between diaphragm support disc (E)
and connecting rod (B).
➨
Screw diaphragm clamping disc (G), dia-
phragm (F), diaphragm support disc (E),
and washers (D) to connecting rod (B).
➨
Optimum torque for the diaphragm support disc: 4.4 ft . lb
f
(6 Nm), it is
recommended to use a torque wrench. Attach torque wrench to dia-
phragm key (hexagonal bolt 6 mm wide).
Note: Never use the diaphragm key with any additional tools like tongs
or Allen keys without appropriate torque limitation.
F
G