Conventional valves, such as butterfly valves, slide valves and brass gate valve in the powder when there are health and stop-flow problems. All of these devices are usually placed on semi-hard bulk containers (RIBC), hopper, feeder or hopper at the bottom, and many parts are immersed in the powder inside. Characteristics of powder to make it very difficult to smooth the flow through the valve, often bridging occurs, the phenomenon of empty or torrents. When the powder on both sides of the backlog in the brass angle valve does not occur when the bridge the flow phenomenon. Powder is caused by empty stranded, and will hold the middle hole, the powder flow from the hole. Backlog and powder, the flow is impeded Runs the contrary, can not control the flow of powder.

     Cutting aids
     In order to avoid the formation of bridge and hollow, in the container wall, or added to hopper vibrators or air gun, and sometimes may also be seen in the hopper adjacent to the operator there will be a hit with a hammer side of hopper. Although these methods have a certain flow of powder to help, but the situation is often worsened the backlog in the production of new, caking or torrents. And easy to create noise pollution and damage to the feeder.