What is a common application for shoulder bolts?

Shoulder bolts, also known as shoulder screws, are specifically designed to create a pivot point or allow for rotational movement between components. The distinct design features a cylindrical shoulder that acts as a guide or bearing surface, facilitating smooth rotation around the shaft of the bolt. This is particularly useful in applications requiring rotating parts, such as in machinery or mechanisms where components need to move freely and precisely without excessive friction.

While shoulder bolts can play a role in fastening two components together by securing them, their primary function is not just holding components together but rather enabling movement. The other options, like supporting structural weight or electrical connectivity, do not fit the intended use of shoulder bolts, which is primarily focused on providing a stable rotational pivot rather than static support or electrical contact.