Hot air circulation oven, after several upgrades, reached the international advanced level; CT series hot air circulation oven for the first generation of products, the average thermal efficiency of about 30%, the use of centrifugal fan, box cardiopulmonary bypass, manual temperature control mode . After repeated transformation, forming a CT-C series hot air circulation oven, the series all use axial fans, equipped with an automatic temperature control system, and equipped with computer-controlled system for selection. Thermal efficiency of about 70%, CT-C series hot air circulation oven is the use of steam or electricity as the heat source, with axial fans for heat convection heat transfer mode heated air, hot air laminar flow through the baking tray with the material for heat transfer. Fresh air from the inlet supplement, waste heat discharged from the air humidity and mouth, constantly replenished with fresh air and exhaust humid air constantly, so to maintain the appropriate relative humidity within the oven. The most important feature of this series is part of the oven circulates hot air inside, the whole process is a closed loop, thus increasing the heat, saving energy. CT, CT-C series hot air circulation oven genus universal drying equipment, to adapt to a wide, widely used in heating the pharmaceutical, chemical, food, light industry, heavy industry materials and products, curing, drying dehydration. Such as: raw material medicine, medicine, Chinese Herbal Medicine, powders, granules, powder, pill bottle size, pigments, dyes, dehydrated vegetables, dried fruit, sausages, plastic resin, electric elements, drying varnish and so on.