① The bed casting exhibits good wear resistance and shock absorption. Due to the graphite in cast iron, which aids in lubrication and oil storage, its wear resistance is excellent. Similarly, the gray cast iron, with its graphite content, has superior shock absorption compared to steel. ② The process performance is favorable. As gray cast iron has a high carbon content, approaching eutectic composition, it has a relatively low melting point, good fluidity, low shrinkage rate, making it suitable for casting complex or thin-walled bed castings. The blank is typically manufactured through casting methods, with most measuring tool castings currently using sand casting. For small-sized measuring tools with high precision requirements, special casting methods can be employed, such as precision casting, investment casting, and centrifugal casting, etc. The selection of the blank during the mechanical processing of casting measuring tools is a crucial step, as it not only affects the blank's processing technology and costs but also influences the mechanical processing methods and quality. Therefore, close collaboration between the two aspects of blank casting and mechanical processing is necessary to reasonably determine the type and structural shape of the blank. The blanks for measuring tools are generally manufactured through casting methods. Currently, most measuring tool castings use sand casting. For small-sized measuring tools with high precision requirements, special casting methods can be utilized, such as permanent mold casting, precision casting, pear-shaped casting, investment casting, and centrifugal casting, etc.