Sand making machine Sand making machine is isolating rock into monomer particles, so that the complete separation of valuable mineral particles . Placer gravel extraction operation also need crushing and grinding process. Just the normal process does not meet. If placer deposits using hydraulic mining method to mine , the rock gravel extraction operations will be finished in the mining process simply. Other mining approach, the synthesis and classification of rocks, ore washing operations often stop in the same device (for example, flat screen or drum) Placer gold category Sand making machine's gravel extraction operation takes a certain power. The unit weight of material power consuming is specification of gravel extraction operation intensity of certain equipment . The more viscous of disposaled material is , the more the power needed. Gold placer based on level of difficulty of material crushing and washing, usually can be divided into washable(including gravel - pebble) ore, medium wash (with a small amount of clay) ores and hard to wash muddy (including a large number of clay) ore. The ration between placer gangue max particle size and placer gold minimum particle size is up to thousands of times, and large pieces of gravel is usually free of gold. Grading operations will be able to separate the bouldersand gravel of the metal free , thus substantially reducing the volume of thecandidate materials. Consumer theory indicate that in the placer gold beneficiation process,washing and grading are critical. Washing without a net can lead to a serious drain on metal , clay indestruction of the sorting operations, resulting in recoveries rates and gold production decreased. Jiang Su Zhongbo washing machine is fully able to meet production requirements. As classification is not good, thickness of the grain mix selection, sorting results are not good, too. Should be a systematic analysis of the particle size, composition of the ore ,and the detailed status of the mines , then work out really feasible washing, grading plan.