Driveshafts

Are what transfers power from the source to the load.  In an automotive situation, the driveshaft takes power from the motor, and supplies it to the differential, and on to the wheels.  This principle is the same whatever the application, the driveshaft is just as important as any other part of your equipment.

What It Is 

A driveshaft is basically just a steel shaft designed to transfer rotational force between a source and a load.  In a vehicle, this is from the motor to the drive wheels.  The shaft has a pivot on at least one end, preferably both, to allow the shaft to operate correctly without needing source and load to be perfectly aligned.  This doesn't mean that they can be stuck in any position.....the driveshaft can generally take a deviation in one plane only.  This means that the source and load may not be aligned vertically, but then must be horizontally, or vice versa.

What Goes Wrong

Since a driveshaft's main operation is rotational, it is required to be extremely well balanced.  Any variation to the balance can cause vibration which increases as the rotational speed increases, potentially causing damage to the driveline components.  

All rotating shafts deflect during operation.  The amount of deflection depends upon the rotational speed, the stiffness of the shaft (the tube diameter and wall thickness), the distance between shaft supports and the angle of connection.  As deflection increases, the balance of the shaft changes and vibration increases.  Driveshafts have to be carefully designed to take into account all of these factors while keeping the shaft light enough to work effectively in the proposed situation.

The most effective way to reduce flex and vibration is to limit the angle of connection at each end of the shaft, which means careful planning of the location of source and load components.

At Loadtek, the technicians are trained in correct driveshaft planning, installation, repair and servicing.  Before you start locating equipment it would pay to contact us to ensure that optimum driveshaft condiditions can be met to maximise the life of your components.

PTO's (Power Take Off's)

Are similar in design and construction to driveshafts.  The main difference is that PTO's are designed for slower speed higher torque applications.  This means that the dynamic rotational balance doesn't have to be as perfect as with a driveshaft, but the shaft and components of the PTO must be able to withstand greater twisting force. as it is more likely a PTO will twist and shear than wobble significantly.

A PTO is made of two separate pieces designed to lock in the middle, allowing for the overall length to increase by as much as 35%.  This means that close tolerances have to be maintained between the two sections to ensure no slippage while under load.  

The yoke (end) connection can be designed with several forms of torque limitations built in, including shear bolt and disc clutch types.  All options including length, tube size and ends need to be carefully designed to meet your needs without overrating or underrating the duty cycle.

Loadtek can supply you with a PTO especially designed to suit your application and requirements, and also arrange fitting, repair or servicing of your existing equipment.

SERVICING

Most driveshaft and PTO manufacturers will agree to servicing schedules set out by vehicle manufacturers guidlines.  The regularity of service also depends on the duty cycle and angle of operation of the shaft.....the greater the angle, the more load is placed of bearings and splines and the more often they need to be checked and lubricated.  If no other guidelines exist, then you should really plan to get your shafts serviced on a regular basis:

Industrial Environment

• 100 hourly

or

• monthly

Automotive

• 3 monthly

or

• 8000km