Heidolph ROTAVAC Vario pumping unit - Manual (Page 54)

page 54 of 61
Documents are only to be used and distributed completely and unchanged. It is strictly the users´ responsibility to check carefully
the validity of this document with respect to his product. Manual-no.: 999248 / 28/04/2011
➨ Lift diaphragm at the side and position carefully together
with diaphragm clamping disc and diaphragm support disc
in the diaphragm key.
☞ Avoid damaging the diaphragm: Do not bend diaphragm
too much.
➨ Check for washers. Do not mix the washers from the dif-
ferent heads. Assemble the original number of washers
between support disc and connecting rod at the individual
pump head.
☞ Smaller number of washers: The pump will not attain final
vacuum. More washers: Clamping disc will hit head cover;
noise or even blockage of the pump.
11.3 Replacing the valves and assembly of the pump heads
☞ Make sure that the square head screw of the diaphragm
clamping disc is correctly seated in the guide hole of the
diaphragm support disc.
☞ Position washers between diaphragm support disc and
rod.
➨ Assemble diaphragm clamping disc, diaphragm and dia-
phragm support disc to connecting rod.
➨ Bring the diaphragms into a position in which they are in
contact with the housing and centred with respect to the
bore.
➨ Lay pump down and support appropriately.
➨ Assemble head covers and valves.
☞ Check for correct position (see also fig. below).