What type of fit is characterized by a shaft being smaller than a hole to allow easy assembly?

A clearance fit is defined as a type of fit where the shaft is smaller than the hole, allowing for easy assembly and movement between the two parts. This means there is intentional space between the parts, which facilitates assembly and ensures that they can operate smoothly without binding or restriction. This type of fit is commonly used in applications where parts need to move freely relative to one another, reducing the risk of wear and tear on the components.

In contrast, interference fits are designed to create a tight bond between two parts, where the shaft is larger than the hole, making assembly more challenging. Transition fits involve a combination of small tolerances that can result in either a clearance or interference fit, depending on the specific dimensions and tolerances of the parts. Form tolerance pertains to the geometric accuracy of parts, not directly to the fit between components. Understanding the distinctions among these types of fits is critical for engineers to ensure proper part functionality and longevity in mechanical applications.