A rotary airlock valve is a valve in which the rotation of a passage or passage in a transverse plug regulates the flow of liquid or gas through the connecting tube. A common plug valve is the simplest rotary valve. Rotary airlock valve has been used in a variety of applications, including: changing the pitch of brass instruments. The steam and exhaust ports of the steam engine are controlled, most notably in the Corliss steam engine. Regularly reverse the air and fuel flow through the open hearth. Load the sample on the column. Certain types of two-stroke engines. Most hydraulic vehicle power steering control valves.

In the industry, rotary airlock valve is used to regulate the flow of a product, usually to reduce the flow to a level that is more suitable for the ongoing process. A typical application is to feed the weigh hopper or to feed the mill that can be blocked by the product.