34
N
S
E
W
N
S
E
W
Leg 1
Leg 1
Leg 2
Leg 2
Leg 3
Leg 3
Leg 4
Leg 4
Leg 5
Leg 5
Leg 6
Leg 6
180"
135"
45"
155.88"
77.94"
Pivot Point
Pivot Point
Required Bridge Leg Elevation Change
'
(Pivot Point Distance)(Out of Plumb)
Shaft Length
Legs 1
%
4
'
(77.94)(32)
434.5
'
5.74 mils
Leg 1
'
(180)(37)
434.5
'
15.3 mils
Legs 2
%
3
'
(155.88)(32)
434.5
'
11.48 mils
Legs 2
%
6
'
(135)(37)
434.5
'
11.5 mils
Legs 3
%
5
'
(45)(37)
434.5
'
3.8 mils
Legs 5
%
6
'
0 mils
Leg 4 is the Pivot Point
'
0 mils
Analytical Shim Calculation - 6 Legged Bridge
Given Data
Shaft Length =434.5"
Bridge Diameter = 180"
Out of Plumb of Center of Runout = 0.037 West, 0.032 South
East-West
North-South
Bridge Shim Calculation
(Thousands of an inch or mils)
Bridge Leg No.
EAST-WEST
NORTH-SOUTH
TOTAL
SHIM
ADDITIONS
1
15.3
5.75
21.04
17.24
2
11.5
11.48
22.98
19.18
3
3.8
11.48
15.28
11.48
4
0
5.74
5.74
1.94
5
3.8
0
3.8
0
6
11.5
0
11.5
7.7
Figure 20.--Analytical bridge shim calculation