Reaming as a finishing process in machining Compared with drilling or boring, which statement best captures the primary advantages and characteristics of the reaming operation?

Introduction / Context:
Reaming is a precision finishing operation used after drilling or boring to bring a hole to an accurate size with an improved surface finish. Unlike roughing operations, reaming removes a very small allowance and is designed primarily for quality rather than speed. This question evaluates your understanding of what reaming actually achieves on a workpiece.

Given Data / Assumptions:

• Reaming follows a pre-formed hole (drilled or bored).
• Only a small allowance (typically 0.1 mm to 0.5 mm, depending on diameter) is left for reaming.
• Goal is accuracy and finish, not bulk metal removal.

Concept / Approach:
The performance indicators for reaming are dimensional accuracy (size control), form/roundness improvement in a modest sense, and a much smoother surface. Since allowance is small, the metal removal rate is inherently low. Selecting the best option requires recognizing that several of these benefits occur together in a properly set up reaming operation.

Step-by-Step Solution:
Identify the nature of reaming: a finishing, sizing, and smoothing process.Link low removal rate to the small allowance characteristic of finishing operations.Link high surface finish to multi-tooth, low feed/low chip thickness action of a reamer.Link high dimensional accuracy to guided tool geometry and minimal deflection.Therefore, all listed positive effects apply simultaneously.

Verification / Alternative check:
Inspection after reaming usually shows a tighter tolerance band and a lower roughness average than after drilling. Production handbooks specify typical H7/H8 grades after reaming (depending on setup), confirming accuracy and finish improvements.

Why Other Options Are Wrong:
Options (a), (b), and (c) are individually true but incomplete; reaming confers all three advantages at once. Option (e) is the opposite of reaming’s purpose.

Common Pitfalls:
Leaving too much allowance (causing chatter) or too little (tool rubs and burnsish only). Misalignment of the pre-formed hole can limit form correction; reaming improves size and finish but does not relocate a badly off-axis hole.

Final Answer:
All of the above