Page 343 - SKF-bearing-housings

Design considerations

Breaking loads and safety factors Table 2
Guideline values for the breaking loads for Breaking loads for SED plummer block housings
housings made of spheroidal graphite cast iron
are listed in table 2. To obtain the permissible
load for a housing, the appropriate breaking
load value should be divided by a factor based
on the safety requirements. In general engin-
eering, a safety factor of 6 is typical († Load
carrying capacity, page 44). P 55°
The permissible load can only be exploited if
the cap bolts are tightened at least to the Housing body Breaking loads
torque values listed in table 3 on page 339. Size P 55°
If the housing is not supported over its entire – kN
base, the load carrying capacity may be 6
affected. For additional information, contact 1 26 000
the SKF application engineering service.
2 30 000
Additional housing support
3 35 000
When loads acting parallel to the support sur- 4 48 000
face occur, a sufficiently strong stop should be
provided to counter the load. 5 49 000
6 69 000

Table 3
Tightening torque values for cap bolts
Housing body Cap bolts (Superbolts)
Size Designation to ISO 262 Jack bolt
Grade 10.9 bolt body Size Tightening torque
– – Nm

1 SB12-M 68x6x300/W M 16x1,5 350
2 SB12-M 68x6x300/W M 16x1,5 350
3 SB12-M 72x6x300/W M 16x1,5 350
4 SB12-M 80x6x350/W M 16x1,5 350
5 SB12-M 80x6x350/W M 16x1,5 350
6 SB12-M 80x6x350/W M 16x1,5 350

339