Pressure gauge block sand platform as the only repair of measuring instruments, it will directly affect the amount of the block repair quality cast ductile iron pressure plate is made of sand, its characteristics are: high-phosphorus alloy, ductile. pressure sand platform to test a variety of precision surface of the other parts (light-gap method), repair of a variety of gauge blocks, work card, measuring tools, optical and other precision parts and tools for other parts of flatness pressure sand platform by JB / T7974-99 standards for manufacturing, mining useful for face grinding process for grinding parts, measuring the repair of this product after grinding of the workpiece surface roughness Ra ≤ 0.08μm. pressure sand platform specifications: 200 × 200, 300 × 200,300 × 300,400 × 300,400 × 400,500 × 300,500 × 400,600 × 400,600 × 500, etc. 9 different specifications, classification of 0, a two level. 
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