An air knife is a tool or system used to blow off liquids, dust, or debris from products, parts, or surfaces, typically as they move along a conveyor. It delivers a high-velocity, controlled sheet of air for cleaning, drying, or cooling in various industrial applications. Air knives are also known as air curtains, air jets or precision drying systems.
Key features include a pressurized plenum with a narrow slot or series of holes that create a laminar, uniform airflow. This airflow can be amplified by the Coandă effect, entraining surrounding air to increase volume and efficiency. Air knives are available in various materials like aluminum, stainless steel, and PVDF to suit different environments. They come in different sizes, ranging from a few inches to several feet in length, and can be customized for specific applications.
Many manufacturers produce air knives including AiRTX International, EXAIR, Streamtek, Sonic Air Systems, Air Knife Systems, and Dereike. Air knives are available from suppliers such as Tameson, and RS Americas. The price range varies widely depending on size, material, and features, with some models starting around $126 and others exceeding $2,000. Availability can range from in-stock to requiring a lead time for custom orders.