Are inch series deep groove ball bearings suitable for some traditional mechanical design and engineering projects?

Yes, inch series deep groove ball bearings are indeed suitable for some traditional mechanical design and engineering projects. These bearings are usually associated with the markets of the United Kingdom and some English-speaking countries, including historical mechanical engineering applications and traditional manufacturing industries.
Traditional mechanical design usually follows old standards and specifications, which may prefer to use imperial units (inches) to define and measure part dimensions. Therefore, inch series deep groove ball bearings may be more common and applicable in these projects, which is different from metric series deep groove ball bearings (measured in millimeters).
In addition, some engineers and designers who have been using inch series bearings for a long time may be more accustomed to these specifications and sizes, so using inch series bearings can be more convenient and economical when designing, replacing and maintaining.
In general, inch series deep groove ball bearings have certain advantages and applicability in traditional mechanical design and engineering projects, especially in those fields that maintain heritage and compatibility with historical standards.