Driveshaft repair is a specific activity, in which it is necessary to take into account many nuances, that at first glance doesn’t seam important. The unit in the process of its operation experiences heavy loads, that can cause defects to appear in various parts of the shaft. It will sooner or later lead to the failure of the entire driveshaft. Therefore, great attention is paid to its inspection. In this article, we will analyze common failures of the driveshaft and their causes.
Preventive Maintenance
Driveshaft inspection should be performed as part of your regular maintenance. Normal vehicle maintenance and recognition of component discrepancies are necessary to prevent serious mechanical problems and avoid driver discomfort. Failure to perform normal maintenance may also void the vehicle warranty.
Inspection of the driveshaft at the service
Inspection of the driveshaft at the service should be made in the presence of the client. It is important, because you can immediately focus his attention on the detected defects, while eliminating a lot of unnecessary questions.
Routine inspection steps
- Check the output and input end yokes for looseness.
- Check for excessive radial looseness of output/input shaft.
- Check for looseness across ends of u-joint.
- Check the slip spline for excessive radial movement.
- Check the shaft for damage, bent tubing, or missing balance weights.
- Check for a loose or missing slip yoke plug.
Common defects
1. Driveshaft flange failure:
Wear of the seating surfaces
Cause:
- Loose bolted connection
- Fracture of the seating surface when installing or removing the driveshaft
- Foreign body between flanges during operation or repair
- Driveshaft vibration
Presence of cracks
Cause:
- Metal defect
- Excessive shock loads
- Driveshaft vibration
- Careless removal of the driveshaft
2. Driveshaft cross failure:
Backlashes between the cross and forks
Cause:
- Wear of the cup hole
- Excessive shock loads
- Driveshaft vibration
- Aggressive driving style
Oil and rust spots on the crosshead
Cause:
- Wear of the sealing dust cap
- Water in the cup
Changing the color of the crossbody cup
Cause:
- Lack of lubricant
- Wear of the sealing dust cap
- Dirt entering the cup
3. Spline joint:
Slotted joint backlash
Cause:
- Natural wear and tear of the splined joint
- Metal fatigue
- Driveshaft vibration
- Wear of rubber cover
- Lack of lubrication
- Dirt between splines
Wear and tear of the rilsan coating
Cause:
- Overheating of the coating
- Material fatigue
- Dust cap wear
- Lack of grease
- Natural wear
4. Driveshaft outboard bearing failure:
Cracks in the rubber bearing
Cause:
- Material fatigue
- Increased driveshaft vibration
- Bearing wear
Wear of the bearing seating surface
Cause:
- Driveshaft vibration
- Bearing wear
- Bearing slippage
- Dirt entering between bearing seating surface and bearing
Bearing wear
Cause:
- Poor quality bearing
- Metal fatigue
- Excessive vibration
- Dirt inside the bearing
Changing the stiffness of the rubber support
Cause:
- Material fatigue
- Low operating temperatures
5. Driveshaft tube failure:
Pipe deflection
Cause:
- Material fatigue
- Increased driveshaft vibration
- Bearing wear
Cracks in the tube
Cause:
- Metal defect
- Welding seam defect
- Excessive vibration
- Intense stress
Dent in the tube
Cause:
- Radial impact
- Deformation of the pipe when removing/installing or repairing the driveshaft
- Incorrectly calculated pipe wall thickness
Afterword
Note how common excessive vibration is on this list. Usually, it’s caused by a lack of balance or poor balance.
This brings our article to an end. If you are interested in equipment for the driveshaft repair or balancing machine to eliminate vibration, you can contact our experts for advice. They will be happy to offer you the best set of equipment for you. Thank you for your attention and good luck in your work.