Cutting vs grinding: which of the following is not classified as a cutting machine in solids processing?

Introduction / Context:
Solids size reduction equipment can be grouped by the dominant mechanism: cutting, compression, impact, or attrition. Correct classification aids in selecting equipment for specific materials (e.g., fibrous, ductile, brittle) and desired product forms (flakes, granules, powders).

Given Data / Assumptions:

• "Cutting" implies blade-based separation (shear) producing chips or slices.
• Tube mills are tumbling grinders with media, not blades.
• Dicers, knife cutters, slitters use edges to shear material.

Concept / Approach:
Dicers, knife cutters, and slitters employ sharp edges and controlled clearances to produce precise cuts, common in food and polymer film processing. Tube mills (a form of ball/rod mill) perform comminution by cascading media that apply impact and attrition, producing powders instead of clean cuts.

Step-by-Step Solution:
Identify cutting machines: dicer, knife cutter, slitter.Recognize tube mill: grinding device using media and rotation.Hence, "Tube mills" is the non-cutting option.

Verification / Alternative check:
Tubular mills are widely used in cement and mineral industries for powder production, confirming they are grinding, not cutting, machines.

Why Other Options Are Wrong:
Dicers/knife cutters/slitters clearly rely on blade shear mechanisms and are standard cutting equipment.

Common Pitfalls:
Assuming any size reduction is "cutting;" many unit operations rely on impact or abrasion rather than shear.

Final Answer:
Tube mills