Tham khảo tài liệu 'root cause failure analysis episode 5', kỹ thuật - công nghệ, cơ khí - chế tạo máy phục vụ nhu cầu học tập, nghiên cứu và làm việc hiệu quả | 9 CONVEYORS Conveyors are used to transport materials from one location to another within a plant or facility. The variety of conveyor systems is almost infinite but the two major classifications used in typical chemical plants are pneumatic and mechanical. Note that the power requirements of a pneumatic-conveyor system are much greater than for a mechanical conveyor of equal capacity. However both systems offer some advantages. Pneumatic Pneumatic conveyors are used to transport dry free-flowing granular material in suspension within a pipe or duct. This is accomplished by the use of a high-velocity airstream or by the energy of expanding compressed air within a comparatively dense column of fluidized or aerated material. Principal uses are 1 dust collection 2 conveying soft materials such as flake or tow and 3 conveying hard materials such as fly ash cement and sawdust. The primary advantages of pneumatic-conveyor systems are the flexibility of piping configurations and their ability to greatly reduce the explosion hazard. Pneumatic conveyors can be installed in almost any configuration requừed to meet the specific application. With the exception of the primary driver there are no moving parts that can fail or cause injury. However when used to ưansport explosive materials the potential for static charge buildup that could cause an explosion remains. Configuration A typical pneumatic-conveyor system consists of Schedule-40 pipe or ductwork which provides the primary flow path used to transport the conveyed material. Motive power is provided by the primary driver which can be either a fan fluidizer or positive-displacement compressor. 112 Conveyors 113 Performance Pneumatic conveyor performance is determined by the following factors primarydriver output internal surface of the piping or ductwork and the condition of the transported material. Specific factors affecting performance include motive power friction loss and flow restrictions. Motive Power The motive .
