Page 78 - Improving Machinery Reliability

50 Improving Machinery Reliability

For instance, the job specifications for centrifugal pumps were examined and con-
struction elements relating to casings, seals, guards, strainers, piping, and pipe sup-
ports tabulated in checklist form. Whenever necessary for clarity, illustration,
remarks, or sometimes cross references were added to the tabulations. These cross
references would point to standardized small-bore (auxiliary) piping or standardized
lubrication specifications, as shown in Figure 1-36.
Similar installation completeness checklists were developed for general-purpose
steam turbines, centrifugal fans, and equipment baseplates. In each case, the end
product was an installation or construction-related tabulation that reduced the con-
tractor's job specification to 10% or 20% of its initial bulk and restated only those

IN5TALLATIOFI COMPLETEIIEL; Page No. 1 01 5
Rev./Oate 0:3-2-79
REVIEW FOR ROTATING Reference Stdnddrd:
MACHINERY Plant Spec. 18-3.2
MACHINERY TYPE: All Exclusions: P-202. P-323
TOPIC OF REVIEW: Lubrication and Bearing Types
The illustrations used in this section cover bearing arrangement and lubricatfon for Flectric
motors, but the bearing types and principles apply to all oil or grease luhriiatrd bearings.
LUBRICATION
I. Ory Sump Oil Mist Lubrication: Shall be applied to machinery with rollinq elemPnsx-
ings only.
2. Wet Oil Sump or "Purge Mist": Shall be applied to machinery with sleeve bearings only.
3. Grease Lubricated Bearings: Uhere specified, shall have accessible grease flttings for
standard grease guns. Fittings must be accessible rlthout
requiring removal of guards or covers.
I ALL ROLLING ELEMENT BEARINGS
1. Double shielded bearings shall not be used with dry sump oil mist lubrication.
A. Double shielded bearings are normally used with grease lubricated bearings.
B. Double shielded bearings are indicated by the bearing identification code letters
"PP" on electric motor nameplates.
2. Sin le shielded bearin s are suitable for dry sump oil mist lubrication on w y Loaaed
ea?,n s. The hie ded' ide of the bearing shall be turned away from the mist cavxf.----~
k h l y lo~ded'motof bearings are indicated by the bearing identification code letters
"lp"
""
8. Single shielded bearings are indicated by the bearing identification code letter "P" on
electric motor nameplates. Inlet and outlet connections shall be at the top and bottom
housing cover.
THRUST BEARINGS ONLY
I. Nan-Shield thrust bearings shall be used with dry sump oil mist lubriiatioz.
FAntifriction thrust bearings are indicated by the bearing identificativ code !etter5
BN. BA, BT. BS, BK, or BG on electric motor nameplates.
B. No letters "P" are allowed in the thrust bearing identification code ri11 r.1ec.l-i~ ,rioter
nameplates.
2. Antifriction thrust bearings shall not be used as coupling end bearings on vertical e!pcIt-i:
motors driving pumps in hydrocarbon service.
A. Oil mist inlet and vent connections on vertical electric motors: Shall be u~rrndnenlli
marked with letter punches.
NOTE: If bearing shields are removed in order to bring equipment into compliance with any of
-
the above guidelines, the letter(s) "P" must be obliterated from the bearing
identification code on the motor nameplate.
Figure 1-36. Illustration completeness review for rotating machinery.