I had a great conversation this week about bearing selection and the intricacies of finding the right press fit. As a quick review, press fit is defined as the value of interference between the shaft and the inside diameter of the bearing, or the housing bore and the outside diameter of the bearing when installed.
Why is press fit important in bearing selection? Check out a recent calculation for our Ultracomp composite material.
In order to generate a proper press fit for our Ultracomp product line, TriStar Plastics requires the housing bore dimension with tolerances, the shaft dimension with tolerances, along with the exposed applications temperature variations. The example below features an example of a press fit utilizing a housing bore of 0.5934/0.5941,” shaft 0.499/0.498 with the temperature varying from 68 deg. F to 200 deg. F.”
To find the right press fit, you must also consider material creep and the vibration that occurs during rotational operation. Without the right fit, bearings can experience stress through extreme friction and heat due to thermal expansion, or they may be exposed to dust or other abrasive particles that are generated. Obtaining secure press fit also allows for torque transfer and for preserving axial location. Read about plastic custom fabrication in our Machining Plastics White Paper.
Key considerations for a good press fit:
We can do a similar calculation for your application, just fill out a Design Worksheet! Or want to discuss your bearing selection with an Expert? Just Ask!