Bearing Clearance Measuring
Bearing clearance, also known as endplay, is the maximum allowable space between the two races of a bearing. It is integral for ensuring the correct bearing performance and should be adjusted to a manufacturer-specified setting for every application. Measuring measuring bearing clearances is relatively simple, provided that you have the correct tools and adhere to a few tips from experienced engineers.
Tools Needed
To measure bearing clearances, you will need a dial indicator, a reference scale, and a feeler gauge. The dial indicator should have the appropriate thread size (1/2”) to mount onto the bearing cup face. The reference scale should have a graduated scale of 0.0002 inches or 0.0005 inches per line. The feeler gauge should relate to the clearance measurements you are taking.
Identify Rotational Position
Prior to adjusting the bearing, you must first identify its rotational position relative to the measuring mechanism. This allows you to make clearance adjustments relative to the same point of contact when re-measuring the bearing clearance.
Mount Dial Indicator
Next, you must mount the dial indicator to the bearing cup face. Ensure that the dial indicator is securely tightened before you continue measuring.
Measure the bearing clearance
Start by zeroing the dial indicator to the reference scale. With the dial indicator zeroed, you can measure the bearing clearance. To do this, you must place the feeler gauge between the bearing cup face and the bearing cone. Rotate the gauge and adjust the reference scale until the gauge slides freely between the two parts. Once the reference scale has been properly adjusted, you can read the bearing clearance as displayed on the dial indicator.
Record the clearance reading
Once you have taken the bearing clearance measurement, you should record the reading in a journal or log book. Additionally, you should also note the bearing type and job code, as this will be useful when referencing the clearance in the future.
Adjust the bearing clearance
Once you have taken the clearance measurement, you should adjust the bearing clearance to the manufacturer-specified setting. If you are not sure of the manufacturer-specified setting, you can consult the manufacturer or the bearing’s technical manual. If the clearance needs to be tightened, first use an adjustable wrench to turn the bearing cone clockwise. If the clearance needs to be loosened, turn the bearing cone counterclockwise.
Re-measure the clearance
Once the adjustment has been made, you should re-measure the bearing clearance to ensure the manufacturer-specified setting has been achieved. Use the same steps and tools to measure the new clearance as you did when taking the initial measurement.
Conclusion
Measuring bearing clearance is a simple process, provided that you have the right tools and adhere to the guidelines outlined in this article. Accuracy and awareness is the key to ensuring that your bearings are adjusted to the manufacturer-specified settings and perform optimally. If you have any doubts, always consult the manufacturer or a qualified engineer for advice on how best to measure and adjust your bearing clearance.
