Scratch and grind the flat plate with lines

Scratching and grinding flat plate is a precision measuring tool used for workpiece inspection, marking, and as a flat reference. It is made of high-strength cast iron or alloy material, with a working surface hardness of HB170-240. It is processed by manual annealing (600-700 ℃) and natural aging (2-3 years) to ensure accuracy stability and wear resistance.