Welding assembly platform is mainly used for testing, measuring, welding, welding, marking, assembly, assembly, dynamic mechanical testing. The material for the HT200-300; hardness HB170-240, accuracy: 0-3; Standard: JB / T7974-1999. Precision: According to the national standard verification procedures JJG117-91 execution, divided into two, three, fine planing three. Size: 4000mm * 8000mm following specifications, larger than this size can be spliced ??using a welding assembly platform for different parts of the plane benchmark gauges welding, and welding plate, no holes above the working surface is flat or with a T-slot! . High-quality high-strength gray cast iron HT200-250, face hardness HB170-240, casting after two annealing 600 ℃ -700 ℃ artificial or natural aging 2-3 years, the complete removal of internal stress, accuracy and stability, good wear resistance. Products made stiffener plate, reasonable design structure. Face not have serious impact on the appearance and performance of sand holes and pores, cracks, slag, shrinkage, scratches, bumps, rust spots and other defects. Sand casting surface should be clear and smooth, painted solid. Registration accuracy level is 0 -3 flat work surface, the hole diameter of less than 15mm of sand of the same material allows the plug, its hardness should be less than the hardness of the surrounding material. Face clogged sand holes should be no more than four, and the spacing between the sand holes should not be less than 80mm. Welding assembly plate should be used to manufacture high-quality platform fine gray cast iron or alloys and other materials, which face hardness should 170-220HB. Face normally be by scraping process. Processing using the scraping of the plate working surface 3, the maximum allowable value of the surface roughness Ra 5um. Face flatness tolerances specified in Table 2. Scraping process should be carried out using painted on research testing. After the research on the area of ??contact points to display a predetermined ratio shown in Table 3: or according to a square area of ??25mm × 25mm a predetermined number of contact points are shown in Table 3, and between any of 25mm × 25mm number of contact points should be less than 5:00