Goulds Pumps 3408 - IOM - Manual (Page 31)

3408 IOM 03/99
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cavity between the bearing and grease fitting. Any greater
amount will, as a rule, be discharged by the seal or vent
and be wasted.
The importance of proper lubrication cannot be over
emphasized. Lubrication frequency depends upon the
speed, size and type of bearing, and operating
temperature or environmental conditions. Generally, the
smaller the bearing and faster the speed, the more
frequent the interval for relubrication with grease. It is
recommended that a certain amount of grease be added
at intervals of three to six months to replace the small
quantity of grease lost between grease flushing intervals.
For average bearing housing designs, one (1) ounce of
grease will be sufficient at these intervals. For larger or
smaller bearing housings this amount may have to be
adjusted.
Unfortunately, there is not a grease available which will
not harden over time and become less suitable for its
purpose due to oxidation. Therefore, it is good practice to
remove all the old grease about once a year and
thoroughly clean the bearings. This should be done
during major overhauls. After gaining experience with
each individual pump and its operating characteristics, the
relubrication and flushing intervals may be adjusted
accordingly. Keep good records and add grease at
regular intervals. Then adjustments can be made after the
first overhaul, if necessary.
PERIODIC ADDITION OF GREASE
Grease lubricated ball bearings are packed with grease at
the factory. Store the pump in a clean, dry place prior to
its first operation.
If one is uncertain about the amount of grease in a
bearing at relubrication intervals, the safe rule is to add
grease slowly (one ounce at a time) as the bearing
operates (if this is safe). Remember, a ball or roller
bearing in most applications is assured of adequate
lubrication if the level of grease is maintained at about the
capacity of the bearing and 1/3 to 1/2 of the cavity
between the bearing and grease fitting. Any greater
amount will, as a rule, be discharged by the seals or vent
and be wasted. Excess grease is the most common
cause of overheating of the bearings. Remove vent plugs
for the first 24 hours of operation after regreasing.
BEARING TEMPERATURE
Normally the maximum desirable operating temperature
for ball bearings is 180° F. Special designs may have
higher limits. Should the temperature of the bearing frame
rise above the limit, the pump should be shut down to
determine the cause. A bearing frame which feels hot to
the touch of the hand is not necessarily running hot.
Check with an accurate temperature measuring device to
be sure.
OIL LUBRICATION OF BEARINGS
Oil lubrication on 3408 pumps is considered special.
Oil lubricated pumps are installed with Trico oilers.
(See Fig. 15) The oilers keep the oil level in the
housings constant at proper level.
After the pump has been installed, flush the housing
to remove dirt, grit, and other impurities that may have
entered the bearing housing during shipment or
installation. Then refill the housing with proper
lubricant. (The housing must be filled using the Trico
oiler.) The oil level will be maintained by the Trico
oiler. (See the SERVICE section for the proper
instructions.)
A Mobil Oil, DTE Medium, or equal, meeting the
following specification will provide satisfactory
lubrication. Similar oils can be furnished by all major
oil companies. It is the responsibility of the oil vendor
to supply a suitable lubricant.
(1) Saybolt viscosity at 100° F . . . . . . . . 215 SSU-240 SSU
(2) Saybolt viscosity at 210° F . . . . . . . . . . . . . .49 SSU
(3) Viscosity index, minimum . . . . . . . . . . . . . . . . 95
(4) API gravity . . . . . . . . . . . . . . . . . . . . . .28-33
(5) Pour point, maximum . . . . . . . . . . . . . . . . +20° F
(6) Flash point, minimum . . . . . . . . . . . . . . . . 400° F
(7) Additives . . . . . . . . . . . . . Rust & Oxidation Inhibitors
(8) ISO viscosity . . . . . . . . . . . . . . . . . . . . . . 46
NOTE: Oils from different suppliers should not
be mixed. Engine oils are not recommended.
The oil should be a non-foaming, well refined, good
grade, straight cut, filtered mineral oil. It must be free
from water, sediment, resin, soaps, acid and fillers of
any kind.
Fig. 15
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