line permits accurate regulation. Cooling water can be circulated through the stuffing box water
jacket (if any) in addition to the external flush.
3.
Cool liquid flushing - product cooling
In this arrangement, pumped liquid is piped from the pump casing, cooled in an external heat ex-
changer, then injected into the seal chamber. A control valve together with a rotometer and/or a
dial thermometer should be installed in a line from the exchanger to the seal circulated. Cooling
water, one to three GPM, should be circulated through the stuffing box jacket, if any.
3.1.5 Connection of drain pipping
All units contain tapped openings around the stuffing box for drainage. On corrosion resistant units, a
drain pan is supplied with a tapped opening. Check the assembly dimension print for size and location.
3.1.6 Connection of equalizing piping
Some multi-stage pumps have equalizing piping to equalize pressure on the stuffing boxes (see Section-
al view
10.1 Sectional View and Parts List on page 55
). This piping is in the box of fittings which accom-
panies the pump. The ends of the piping must be connected to the openings in each stuffing box.
3.1.7 Impeller adjustment
Some end suction pumps, in addition to vertical pumps, have means of adjusting impeller clearance with-
in the casing. The clearance was set at the factory, but in transit, the clearance may have been lost.
Proper clearance must be attained before a pump is operated or serious damage may occur. Check and
reset impeller clearance by method described in
6.2 Impeller clearance adjustment on page 35
.
3.1 Pump Bearings
26
Model 3415 Installation, Operation, and Maintenance Manual