D28 is a heavy-duty 3D flexible welding table with 28mm diameter holes and 100mm hole pitch, featuring through holes and grid lines on five surfaces. Made of cast iron/steel with nitriding treatment, it offers high load capacity and precision (flatness 0.1/1000mm). Ideal for large/heavy workpieces in steel structures, engineering machinery, shipbuilding, and energy equipment; enables fast positioning, flexible fixture combination, and improved welding accuracy and efficiency.