How much greater should bearing block dimensions be compared to the nominal diameter?

The standard practice for determining the dimensions of bearing blocks in relation to the nominal diameter is to ensure adequate coverage and structural integrity. A common guideline is to make the bearing block dimensions at least 3% greater than the nominal diameter of the load-bearing component. This allowance accommodates potential variations in the size and positioning of the components, ensuring that there is sufficient area to distribute load and provide stability during testing and the final application.

Choosing 3% as an increment helps to minimize the risk of uneven load distribution or stress concentrations that could lead to structural failures. It also aids in avoiding issues related to misalignment and provides enough surface area for secure interface with the testing apparatus or structural element.