According to the way of heat transfer to the veneer, it is divided into: 1 air convection dryer. The heat is transferred to the veneer by means of hot air convection to dry the veneers, such as various mesh belt dryers. 2 contact dryer. The hot steel plate is in contact with the single plate, and the heat is directly transmitted to the veneer to dry the veneer, such as a hot plate dryer. 3 radiant dryer. The radiant energy such as microwave and infrared rays (including far infrared rays) is used as a heat source to dry the veneers. 4 compound dryer. It is the composite drying of the above several methods. For example, the heat transfer mode of the roller dryer is convection-contact composite heat transfer.
According to the transfer mode of the veneer, it can be divided into two types: a roller dryer and a mesh belt dryer. The roller and mesh belt dryers are further divided into a roller dryer, a jet roller dryer, a mesh belt dryer and a jet belt dryer according to whether the circulating hot air is vertically sprayed onto the surface of the veneer. The jet mesh belt dryer has wide application because of its high drying speed, the ability to enter the board in the transverse direction, and the advantages of the first dry and rear shearing process. The jet roller dryer also has the advantages of smoothing the flat veneer and good quality, and is suitable for drying the single veneer with a thickness of 1.0 mm or more, and becomes one of the main veneer drying devices.
Structure and performance
The dryer is mainly composed of a drying section and a cooling section. The drying section is used to heat the veneer and accelerate the discharge of moisture in the veneer by circulating hot air. The drying section is composed of several sub-chambers, each of which has the same structure, and the two compartments are connected by screws. The longer the drying section, the higher the efficiency of the dryer. The cooling section is to suck the outdoor cold air from the suction pipe through the fan, and pass through the cooling compartment horizontally. The other side fan discharges the air into the atmosphere through the exhaust pipe, and cools the dried veneer, generally from 1 to 2. Each compartment is composed. Any type of dryer can be divided into a frame, a transmission, a cooling section, a thermal insulation wall and an auxiliary device, but different types of dryers have both commonality and particularity.