PUMP COOLING REQUIREMENTS
Pumps may be furnished with the following jackets or cooling coil:
1) Stuffing box
2) Mechanical seal gland (optional)
3) Casing pedestals (optional)
4) Bearing housing cooling coil (optional)
Cooling is recommended under the following conditions:
STUFFING BOX COOLING
1) With a mechanical seal when the application requires
cooling.
2) With a mechanical seal when pumping liquids of 0.75 specific
gravity, or less, when the pumping temperature permits further
cooling.
3) With stuffing box packing, except Grafoil, at temperatures
above 250°F.
MECHANICAL SEAL GLAND COOLING
When the mechanical seal application requires cooling of the
seal faces. This depends on the liquid pumped and the pumping
temperature.
BEARING HOUSING COOLING
At pumping temperatures below 500°F, such cooling is rarely
necessary. Excessive cooling of the bearing housing may lead
to early bearing failure from moisture condensation and contami-
nation of the oil.
COOLING WATER PIPING
The cooling water piping depends on what cooling coil or jackets
are furnished and used. Jackets to be piped in series are, Casing
Pedestal Cooling, Stuffing Box Cooling, and Bearing Housing
Cooling, with the cooling water to flow in that sequence. Not all of
these jackets will necessarily be used. All other jackets or cooling
coil should be piped in parallel with separate flow to each. The cus-
tomer must provide piping and a shut-off valve on each cooling inlet.
The customer must also provide the outlet piping from each jacket or
cooling coil, fitted with a pressure relief valve set at a maximum of
150 PSIG, and then a flow control valve. Pipe each outlet from the
valve to it's own sight drain or through a suitable flow indicating
device into the plant cooling water system.
In no case should the outlets be piped into the municipal water
system.
COOLING WATER FLOW RATES
Stuffing box cooling,
when used, has flow rates related to pumping
temperature. See the chart below. The lower flow rates will lead to
higher cooling water temperature and promote more rapid scaling
within the jacket. Higher flow rates will do no harm.
Mechanical seal gland cooling
flow should be adjusted to about 1/2
GPM.
Bearing housing cooling
flow rate, when not in series with the stuff-
ing box cooling, should be adjusted to 1/2 GPM. This will maintain
the oil temperature below 130°F at all pumping temperatures.
The pumps may be operated without bearing housing cooling if
experience with the particular installation shows that the bearing
temperature, without cooling, does not rise above 200°F.
As stated before, pumps operating at 500°F and lower, seldom
require bearing housing cooling.
Casing pedestal cooling
flow rates are equal to stuffing box cooling
flow rates when piped in series. If piped separately, the flow need
not be over 1/2 GPM.
WARNING—EXTREME HAZARD TO PERSONNEL: When cool ing
water is used to cool the stuffing box, gland, or bearing housing
jackets, it is mandatory that the cooling water be allowed to flow at
any time the pump is running. Closing the inlet and/or outlet valves
under running conditions may result In the water In the jackets
reaching high pressure which may lead to the rupture of a water
jacket with extreme hazard to personnel.
WARNING—EXTREME HAZARD TO PERSONNEL: Improper connec-
tion of cooling water piping may result in the injection of cooling
water into the pump stuffing box and into the pumpage. Depending
on temperature this may cause a violent steam explosion in the
pump, piping, or associated equipment with extreme hazard to per-
sonnel. It may also cause serious contamination of the pumpage and
heavy corrosion of pump or equipment parts.
CASING PEDESTAL COOLING
Casing pedestal cooling is used to equalize and minimize thermal
expansion of the pedestal pump supports.
300
300
400
500
600
700
800
200
200
100
50
100
TYPICAL SEAL CHAMBER
COOLING DATA
BASED ON COOLING
WATER INLET
TEMPERATURE OF 70
O
F,
AND PUMPING HEAT
TRANSFER LIQUID
FLOW RATE-GPM
PUMPING TEMPERATURE-F
Temperature of Pumpage in the Seal Cavity
6
1
2
3
4
5
C
ASING
B
ACK
C
OVER WITH
J
ACKETED
S
TUFFING
B
OX
AS VIEWED FROM THE MOTOR END OF THE PUMP
,
SHOWING THE PIPING CONNECTIONS
.
SEAL CHAMBER
CONNECTION
JACKET COOLING
INLET
JACKET COOLING
OUTLET
WARNING: Improper con-
nection of cooling and/or
seal connection piping may
be dangerous and may
seriously damage pump
and system.
SEAL CHAMBER
CONNECTION
