Step 1: Understand the characteristics of different CMM types.
Coordinate Measuring Machines (CMMs) come in various configurations, each suited for different applications based on size, accuracy, and workpiece weight.
Cantilever type CMMs: These have the measuring probe mounted on a cantilever arm. They offer good access to the workpiece and are typically used for small to medium-sized components. They are generally not as rigid as bridge types and thus less suited for very large and heavy workpieces.
Bridge type CMMs: These are very common, offering high accuracy and rigidity. They have a bridge structure that moves along a granite base. They are suitable for a wide range of workpiece sizes, including medium to large.
Floated bridge type CMMs: A variation of the bridge type where the bridge "floats" on air bearings, providing very high accuracy and precision, especially for high-speed measurements. They are still within the general scope of bridge CMMs in terms of their overall structural capability for heavy workpieces.
Horizontal boring mill type CMMs (also known as horizontal arm CMMs or gantry CMMs): These CMMs are characterized by a horizontal arm that extends from a sturdy column. They are particularly robust and can be integrated with floor-mounted rotary tables, making them exceptionally well-suited for very large, heavy, and often irregularly shaped workpieces that might be difficult to load onto traditional CMM beds. Their open structure allows for easy loading and unloading of massive components.
Step 2: Identify the CMM best suited for large heavy workpieces.
Given the structural design and application suitability, the Horizontal boring mill type (or horizontal arm/gantry CMM) is specifically designed to handle very large and heavy workpieces due to its robust construction and accessibility.
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