Nexen RSTC1100 964528 - Manual (Page 26)

FORM NO. L-21204-C-0908 26
APPENDIX
SERVICE INSTRUCTIONS
Nexen does not recommend customer servicing of this product. Contact Nexen for replacement parts or repair.
The value of WK 2 is important for applications involving
timed, cyclic duty or when starting or stopping heavy
loads. Use one or all of the three methods shown here
to estimate the inertia.
1. The inertia of solid steel shafting is given in the
following table. The values given are per inch of shaft
length.
To determine WK 2 of a normal shaft or disc, multiply
the WK 2 from the chart by the length of the shaft or
thickness of the disc in inches.
Note: For hollow shafts, subtract WK 2 of the i.d. from
WK 2 of the o.d. and multiply by the length.
2. For solid cylinders of a given weight, WK 2 is estimated
by:
Where: WK 2 = intertia in lb ft 2
R = cylinder radius in feet
W = weight in pounds
3. For solid or hollow cylinders, the inertia is calculated
by the following equations:
Solid Cylinder: Hollow Cylinder:
WK 2 = .000681 p LD
4
WK 2 = .000681 p L (D
2
4 -
D
1
4 )
Where WK 2 = lb ft 2
D, D
1
, D
2
, and L are in inches
p = lb/in 3
where p (aluminum) = .0924
p (cast iron) = .260
p (steel) = .282
Calculate the inertia of complex, concentric, rotating
parts by breaking the part into simple cylinders,
calculating the inertia or each, and summing the values.
WK 2 = W ( )
R 2
2
D
L
Dia
(in.)
WK 2
(lb ft 2 )
Dia
(in.)
WK 2
(lb ft 2 )
Dia
(in.)
WK 2
(lb ft 2 )
0.750 0.00006 7.500 0.6110 13.250 5.9600
1.000 0.0002 7.750 0.6990
13.500 6.4200
1.250 0.0005 8.000 0.7910 13.750 6.9100
1.500 0.0010 8.250 0.8950 14.000 7.4200
1.750 0.0020 8.500 1.0000 14.250 7.9700
2.000 0.0030 8.750 1.1300 14.500 8.5400
2.250 0.0050 9.000 1.2700
14.750 9.1500
2.500 0.0080 9.250 1.4100 15.000 9.7500
2.750 0.0110 9.500 1.5500 16.000 12.6100
3.000 0.0160 9.750 1.7500 17.000 16.0700
3.500 0.0290 10.000 1.9300 18.000 20.2100
3.750 0.0380 10.250 2.1300 19.000 25.0800
4.000 0.0490 10.500 2.3500 20.000 30.7900
4.250 0.0630 10.750 2.5800 21.000 37.4300
4.500 0.0790 11.000 2.8300 22.000 45.0900
5.000 0.1200 11.250 3.0900 23.000 53.8700
5.500 0.1770 11.500 3.3800 24.000 63.8600
6.000 0.2500 11.750 3.6800 25.000 75.1900
6.250 0.2960 12.000 4.0000 26.000 87.9600
6.500 0.3450 12.250 4.3500 27.000 102.3000
6.750 0.4020 12.500 4.7200 28.000 118.3100
7.000 0.4640 12.750 5.1100 29.000 136.1400
7.250 0.5350 13.000 5.5800 30.000 155.9200