The Pallet rack/beam rack is the most widely used rack type, which has advantages of stable structure, high carrying capacity and convenient picking-up. It is composed of load-bearing upright frames and beams, which are connected by hanging with safety pins. The distance can be adjusted at a height of 50 and 76mm. The upright frames are fixed to the ground with expansion bolts. The bottom layer of the rack is placed on the ground with 2-3 pallets in each layer in general. The length of beams and depth of upright frames are depending on the size of pallets. Such a rack can flexibly equip with some safety or convenience components, such as support bar and rear support bar of pallets, wire mesh laminate, anti-collision protector and connecting beams. The rack layout is generally divided into the standard-aisle type, narrow-aisle type (VNA) and double-deep type, equipped with appropriate forklifts. Too many aisles may reduce the utilization rate of the warehouse, but the narrow-aisle type (VNA) and double-deep type can avoid such a shortcoming. In addition, because of its unique cargo management capabilities and extremely convenient pick-up functions, beam racks have become the first choice for logistics companies and other enterprises.