Pump Solutions Group Neptune Series 6000 dia-PUMP MODELS 6100 thru 6250 - Manual (Page 21)

21
SECTION IX
DOUBLE DIAPHRAGM OPTION
Special Instructions for Series 6000 “dia-Pumps” with Double Diaphragm
The instructions below are for Neptune’s optional Double Diaphragm Kit.
Use of a double diaphragm allows diaphragms to be
monitored and provides an early warning upon failure of
either diaphragm allowing repairs to be made before
process fluid can mix with the pump’s hydraulic fluid.
Neptune’s double diaphragm is a kit, which may be
retrofitted to any pump currently in service or may be
installed on a new pump at the factory.
Figure 4, illustrates a Double Diaphragm Assembly.
An intermediate plate is located between the oil and
liquid heads with one diaphragm on each side of the
intermediate plate. The Intermediate Plate is
connected to a rupture alarm or pressure switch via a
capillary system. The area between the diaphragms
is evacuated. Rupture in either diaphragm produces
an increase in volume and, therefore, a pressure
increase, which can be sensed by a pressure switch
for alarm purposes.
DISASSEMBLY OF INTERMEDIATE PLATE
11.0.0 Shut pump off and disconnect suction and
discharge piping. Remove drain plug and
drain hydraulic fluid from the gearbox.
11.0.1 Remove 8 Screws and remove the liquid
head assembly. Some hydraulic oil and
process fluid will spill out when the head is
removed.
11.0.2 The intermediate plate, which is between the
pump heads can be removed easily.
11.0.3 Remove the rupture alarm (pressure switch)
and clean the capillary system.
11.0.4 Replace one or both diaphragms if needed.
11.0.5 To reassemble reverse above procedure. Be
certain that parts align properly.
FIGURE 4
VACUUM AIR FROM INTERMEDIATE SPACE
11.0.6 Open valve Item No. 5 (Figure 5).
11.0.7 To remove air, attach the vacuum pump with a hose connection Item No. 6 to the valve
Item No. 5 (Figure 5). The intermediate space is evacuated to 3 psig for normal operating
conditions.
11.0.8 Close valve Item No. 5 (Figure 5).