x s Shaft seals see pages onwards For detail B3HH-9-C Bevel-helical gear Reduction Box B3

Flender/Flender Gear Units/Bevel-helical gear Reduction Box B3

practice-oriented method to assess oil foaming behavior. The pour point should be at least 5 below the lowest operational temperature of the lubricant. Synthetic oils are more favourable than mineral oils in this respect. Depending on the application, attention may also need to be paid to oil water separation ability and air release property. 3.6.5 Oil Feed Splash lubrication is preferred as simple, operationally reliable lubricating systemfor low and medium circumferential speeds up to roughly 2 /. Given suitable internal oil guiding devices in the housing, splash lubrication can still be used at circumferential speeds up to 5 /. An oil level at which the complete face width of the wheel is fully immersed in the sump should be ensured duringoperation. The oil level while the gear is not running should be correspondinglyhigher if the oil has to travel some distance, for example to the distant bearings of apinion shaft. The quantity of oil supplied is often sufcient to provide lubricantlm with enough oil, but the majority of the oil is required to dissipate contact heat.Hypoid gears with large offsets, which generate considerable frictional heat,impose increased demands in this respect. Forced lubrication is employed for unfavourable shaft positions and continuous circumferential speeds >2 /. This more complex method requires additional elements in the form of pump, lter and cooler, but allows continuous oil manage-ment. The injected quantity is chosen such that heat generated in the contact isdissipated completely via the oil, using the designed temperature difference of an9 3 Design external radiator. Additional heat dissipation is also possible via thermal convection and radiation from the housing. The oil is usually sprayed into the ingoing mesh, producing the lowest gear bulk temperatures at that point. If no-load losses at high circumferential speeds are to be kept low, part of the oil can also be sprayed into the outgoing mesh to cool the gearafter conta