Page 119 - Improving Machinery Reliability

Machinery Reliability Audits arid Reviews 91

Table 3-2
Clearance Variations With Tolerances
Dimension Minimum Maximum
Bearing Bore, in. 3.0040 3.0070
Journal Diameter, in. 2.9990 3.0000
Pad Curvature (Diametrical), in. 3.0070 3.0090
CB CP Preload Brg. Bore Pad Bore Journal OD
mils mils M (dim) in. in. in.
2.50 4.00 0.3750 3.0040 3.0070 2.9990
2.50 5 .OO 0.5000 3.0040 3.0090 2.9990
4.00 4.00 0.0000 3.0070 3.0070 2.9990
4.00 5.00 0.2000 3.0070 3.0090 2.9990
2.00 3.50 0.4286 3.0040 3.0070 3.0000
2.00 4.50 0.5556 3.0040 3.0090 3.0000
3.50 3.50 0.0000 3.0070 3.0070 3.0000
3.50 4.50 0.2222 3.0070 3.0098 3.0000
CB is rhe assembled radicil clearatice.
CP is the rriachrrred rccclial clearatice.
M is the bearing preload foetor.

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- __ BALANCED
9
0 2000 4088 6000 6000 I0008 12000 14880
RUNNING SPEED, RPH
Figure 3-5. Comparison of balanced mechanical run and out-of-phase unbalance sen-
sitivity test.