User guide

Thrust bearings
The 3171 comes with a grease-lubricated duplex thrust bearing. The bearing is pre-lubricated at the
factory. Regrease the bearing according to the schedule in the following table.
Table 2: Lubricating intervals in operating hours
Drive-unit size
group
Below 1800 RPM 1800 RPM 3000 RPM 3600 RPM
S/ST 2,000 2,000 1,200 750
M/MT 2,000 1,800 800 450
L 2,000 1,200 - -
Lubricate the bearings after a shutdown period
1. Flush out the bearings and bearing frame with a light oil to remove contaminants.
During flushing, make sure to rotate the shaft slowly by hand.
2. Flush the bearing housing with the proper lubricating oil to ensure oil quality after cleaning.
Lubricating-grease requirements
Precautions
• NOTICE: Never mix greases of different consistencies (NLGI 1 or 3 with NLGI 2) or with
different thickeners. For example, never mix a lithium-based grease with a polyurea-based grease.
Doing so may result in decreased performance.
• NOTICE: Remove the bearings and old grease if you need to change the grease type or consistency.
Failure to do so may result in equipment damage or decreased performance.
Bearing temperature
Bearing temperatures are generally about 20°F (18°C) greater than bearing-housing outer surface
temperatures.
This table shows the type of grease required for the operating temperature of the pump.
Bearing temperature Type of grease
5°F to 230°F (-15°C to 110°C) Use a lithium-based mineral-oil grease with a
consistency of NLGI 2.
Exceed 350°F (177°C) Use a high-temperature grease. Mineral-oil greases
should have oxidation stabilizers and a consistency
of NGLI 3.
Grease recommendations based on temperature
Most pumps use Sunoco 2EP grease. High temperature units that can pump fluids with a temperature
greater than 350° F (177°C) use Mobil SCH32.
This table shows which brand of grease to use when lubricating the pump.
Brand When temperature of pumped
fluid is less than 350°F (177°C) -
NLGI consistency 2
When temperature of pumped
fluid is greater than350°F
(177°C) - NLGI consistency 3
Mobil Mobilux EP2 SCH32
Exxon Unirex N2 Unirex N3
Sunoco Mutipurpose 2EP N/A
SKF LGMT 2 LGMT 3
Maintenance (Continued)
36 Model 3171 Installation, Operation, and Maintenance Manual