ENGINIEERING INFO (ROLLERS)
Engineering Information of FYH Spherical Roller Bearings
Spherical Roller Bearing Life Calculations
The relationship between the basic rating life, the basic dynamic load rating, and the dynamic equivalent load of the spherical roller bearing is indicated in 1. If the spherical roller bearing unit is being used at a fixed rotating speed, the life is indicated as time. This is shown in 2.


L10:Basic Rating Life 10⁶rotations
L10h:Rated Life (hr)
Cr:Basic Dynamic Load Rating (lbf)
Pr:Dynamic equivalent Load (lbf)
n:Speed (min-¹)



Dynamic Equivalent Load
In many cases, a bearing is exposed to the combined vector load of both radial and axial load components. It may also be used under more severe conditions such as vibration and shock load. In this case, a direct comparison to the dynamic load rating is not appropriate. In such a case, find the load equivalent to a direct radial load only and compare this with the basic dynamic load rating. The converted virtual load is called dynamic equivalent load (Pr).

Calculation of dynamic equivalent load
The dynamic equivalent radial load (Pr) of a bearing that bears radial and axial loads as well as vibration and impact is found by the following formula.


Pr:Dynamic equivalent radial load, N
Fr:Radial load, N
Fr:Axial load, N
X:Radial load factor
Y:Axial load factor

Radial load factor ( X ) and axial load factor ( Y )
Basic Loads(lbf) e Fa / Fr <e Fa / Fr >e
Size Code Dynamic Cr Static Cor   X Y X Y
XS408 ZS408 19967 22744 0.28   2.41   3.59
XS409 ZS409 20834 24491 0.26   2.57   3.59
XS410 ZS410 21683 26306 0.24 1 2.77 0.67 3.82
XS411 ZS411 27191 33029 0.24 1 2.83 0.67 4.12
XS412 ZS412 39006 49591 0.25 1 2.71 0.67 4.21
XS413 ZS413 39006 49591 0.25 1 2.71 0.67 4.03
XS414 ZS414 42032 42032 0.22 1 3.00 0.67 4.03
XS415 ZS415 42032 54986 0.22 1 3.00 0.67 4.47
XS416 ZS416 63910 86343 0.24 1 2.86 0.67 4.47
XS417 ZS417 63910 86343 0.24 1 2.86 0.67 4.25
XS418 ZS418 63910 86343 0.24 1 2.86 0.67 4.25
XS420 ZS420 81897 111863 0.24 1 2.78 0.67 4.14
  *e is the Thrust load to radial load factor.



Load factor

Even if the static radial load and the axial load can be accurately calculated, the actual loads are generally greater than the calculated figures. This is due to the presence of vibration and shock load during actual machine operation.
To find the loads actually applied to a bearing, multiply the values determined for the static load by the following load factors.



F: Load actually applied to bearing, N
Fc:Theoretically calculated load,
fw:Load factor



Load factor fw
Operating conditions Applications fw
Virtually no vibration or impact Electric machines and instruments 1 -1.2
Ordinary operation
(light impact)
Agricultural machines and blower 1.2-2
Great vibration and impact Construction machines and grinders 2 -3
Limiting Speed for Seals
SIZE Standard Triple Lip Seal Limiting Non Contact Seal Limiting
XS408 2750 3200
XS409 2450 2800
XS410 2200 2600
XS411 2000 2360
XS413 1692 2000
XS415 1460 1730
XS418 1220 1440
XS420 1100 1300




Distribution of Bearing Load
In order to determine the radial load distribution to each bearing attached to a shaft, use the procedure shown below.










Allowable Radial Load (lbf) at Various RPM
SHAFT SIZE SIZE L10h RPM
50 100 150 300 500 750 1000 1200 1400 1600 1800 2000 2200 2400 2600 2800 3000 3200
1 3/8"
1 7/16"
1 1/2"
40 mm
XS408 10000 7197 5846 5177 4205 3607 3194 2930 2774 2649 2545 2456 2380 2313 2253 2200 2151 2107 2067
25000 5468 4441 3932 3194 2740 2426 2226 2107 2012 1933 1866 1808 1757 1712 1671 1634 1601 1570
50000 4441 3607 3194 2594 2226 1971 1808 1712 1634 1570 1516 1468 1427 1390 1357 1327 1300 1275
70000 4015 3261 2887 2345 2012 1782 1634 1547 1477 1419 1370 1327 1290 1257 1227 1200 1175 1153
100000 3607 2930 2594 2107 1808 1601 1468 1390 1327 1275 1231 1193 1159 1129 1102 1078 1056 1036
1 11/16"
1 3/4"
45 mm
XS409 10000 7510 6100 5401 4387 3764 3333 3057 2894 2764 2655 2563 2483 2413 2351 2295 2245
25000 5705 4634 4103 3333 2859 2532 2322 2199 2099 2017 1947 1886 1833 1786 1744 1705
50000 4634 3764 3333 2707 2322 2056 1886 1786 1705 1638 1581 1532 1489 1451 1416 1385
70000 4189 3402 3013 2447 2099 1859 1705 1615 1542 1481 1430 1385 1346 1311 1280 1252
100000 3764 3057 2707 2199 1886 1670 1532 1451 1385 1331 1285 1245 1209 1178 1150 1125
1 15/16"
2"
50 mm
XS410 10000 7816 6349 5621 4566 3917 3469 3182 3012 2876 2763 2667 2584 2512 2447 2389
25000 5937 4823 4270 3469 2976 2635 2417 2288 2185 2099 2026 1963 1908 1859 1815
50000 4823 3917 3469 2817 2417 2140 1963 1859 1775 1705 1646 1595 1550 1510 1474
70000 4360 3541 3136 2547 2185 1935 1775 1680 1604 1541 1488 1442 1401 1365 1332
100000 3917 3182 2817 2288 1963 1738 1595 1510 1442 1385 1337 1295 1259 1226 1197
2 3/16"
55 mm
XS411 10000 9801 7961 7049 5726 4912 4350 3990 3778 3607 3465 3345 3241 3150
25000 7446 6048 5355 4350 3732 3304 3031 2870 2740 2632 2541 2462 2393
50000 6048 4912 4350 3533 3031 2684 2462 2331 2226 2138 2064 2000 1943
70000 5467 4441 3932 3194 2740 2426 2226 2107 2012 1933 1866 1808 1757
100000 4912 3990 3533 2870 2462 2180 2000 1893 1808 1737 1676 1624 1579
2 7/16"
65 mm
XS413 10000 14060 11421 10113 8214 7047 6240 5724 5419 5174 4971 4798 4649
25000 10681 8676 7682 6240 5353 4740 4348 4117 3931 3776 3645 3532
50000 8676 7047 6240 5068 4348 3850 3532 3344 3193 3067 2961 2869
70000 7843 6370 5641 4582 3931 3480 3193 3023 2886 2773 2677 2593
100000 7047 5724 5068 4117 3532 3127 2869 2716 2593 2491 2405 2330
2 11/16"
2 15/16"
75 mm
XS415 10000 15151 12307 10897 8851 7594 6724 6168 5840 5576 5357
25000 11510 9349 8278 6724 5768 5108 4685 4436 4236 4069
50000 9349 7594 6724 5461 4685 4149 3806 3603 3440 3305
70000 8451 6864 6078 4937 4236 3750 3440 3257 3110 2988
100000 7594 6168 5461 4436 3806 3370 3091 2927 2794 2685
3 7/16"
90 mm
XS418 10000 23037 18712 16569 13458 11546 10224 9378 8879 8478
25000 17500 14215 12587 10224 8771 7766 7124 6745 6440
50000 14215 11546 10224 8304 7124 6308 5787 5479 5231
70000 12850 10437 9242 7507 6440 5703 5231 4953 4729
100000 11546 9378 8304 6745 5787 5124 4700 4450 4249
3 15/16"
100mm
XS420 10000 29521 23979 21232 17246 14796 13101 12018 11378 10864
25000 22426 18215 16129 13101 11240 9952 9129 8643 8253
50000 18215 14796 13101 10641 9129 8084 7415 7021 6703
70000 16467 13375 11843 9620 8253 7308 6703 6347 6060
100000 14796 12018 10641 8643 7415 6566 6023 5703 5445
  1.   Blue area The Standard Triple Lip Seal is used.
  2.   Green area A non-contact seal is used.