Ⅰ.Structure of the kiln body
The aluminum alloy kiln body uses special aluminum alloy shape as framework. The special aluminum alloy shape are connected by stainless steel bolt. The inner plates of kiln body are made of anticorrosive aluminum alloy plates which have been curved and are fixed to the framework with stainless steel bolt. Between aluminum alloy plate and the plate , the seams are sealed by the sealant specially made , and between the plate and the shape. So that the kiln is sealed well. The outer plates are made of ladder-shape aluminum alloy template. High density glass wool is stuffed as heat insulation material between the inner plate and the outer template. The whole kiln body is well-built and durable; the function of heat insulation is well . Additionally, The manufactory also provides brick structure kiln , and providing the drawing of the building and basement . Clients can build a brick house according to the drawing, then the manufactory installs corresponding component in the brick house. This kind of brick structure kiln is economic and functional ,the drying effect of the timbers is also the same as the aluminum alloy structure.
II. Main Door System
The kiln main door is completely made of aluminum alloy (the door of the brick and concrete mixed structure drying kiln also uses this kind). The main door uses aluminum shape as frame, the inner plate is made of anticorrosive aluminum , the outer plate is made of ladder-shape aluminum plate, high density glass wool is stuffed as heat insulation material between the inner plate and the outer plate. Folling locking bracing axle sleeve fixed at the two edges of the main door; and locking cant-plate fixed on the door-frame. When the main door is laid down, it can lock automatically depending on its own weight. The door and the door-frame is sealed with special rubber strip. The hanger of the main door is of motor-trolley structure, being made of steel. After the main door is lifted up, the door can move along the track with the hanger from left to right and vice versa, so that door can full be open for the convenience of loading and unloading the timber.
III. Inspection Door
The small checking door is also made of aluminum alloy completely and the small door uses aluminum shape as frame, the inner plate is made of anticorrosive aluminum , the outer plate is made of ladder-shape aluminum plate, high density glass wool is stuffed as heat insulation material between the inner plate and the outer plate. The checking door and the door-frame is connected by hinge. The small door and the door-frame is sealed with specially made rubber strip. Handle type lock fixed On the middle part of the other side of the door. It locks automatically when the door closes. On the rear part of the handle of the lock, a push rod is fixed and leading directly to the inner of the kiln . The operator in the kiln can open the checking door only by pushing outward the push rod, which guarantees the operator is safe.
IV. Pipeline System
Drawing a main inlet air pipeline in the operation room, separating it into two branch pipelines after the steam gets through main valve, one is heating branch, the other is spraying branch, passing both branches ,steam filter and solenoid valve are both fixed separately, aside the heating valve and the spraying valve the manual by-pass valve is fixed separately. The heating branch connects with the entering pipe of the radiator, the drain pipe of the radiator connects with the return water pipe. At the tip of the return water pipe,steam trap and by-pass valve fixed, the steam trap withholds the steam, letting the condensed water get through the valve hole. The spraying branch connects the spraying pipe inside the kiln. The by-pass valves on the two branches can be used to manually heat, spray. The by-pass valve on the return water branch can be used to eliminate the condensed water in the pipeline quickly, to avoid the steam and the water mixing in the pipeline and forming lashing.
They adopt the duplex metal structure and using the stainless steel pipe as the core pipe that is entwining aluminum fin around the core pipe. two ends of a few pipes entwined with fin are parallelly welded and connected with two pillars to make it a group, the quantity of groups is allocated according to the capacity of the drying kiln. When turning on the heating control valve, the steam goes through the radiator, the temperature of the kiln rises, then heating up the timbers.
VI. Spraying Pipeline
A stainless steel long pipe is fixed above the wind channel at the back kiln, that is ,to connect it with the inlet air pipe outside the kiln. There are many small holes on the long pipe which the steam passes through. During the timbers is dried, according to the drying technology, when it needs, to turn on the spraying control valve on the pipeline system, steam is sprayed into the kiln through the small holes on the spraying pipe, which can increase the humidity of the air dielectric in the kiln, and make it reach demanded value, guarantee the timbers’ drying quality.
VII. Air-blower Circulatory System
A second-storied shed is at the distance of 1.2 meters from the ceiling in the kiln, separating the room of the kiln into two parts,（ that means the second-storied shed is 1.2 meter from the ceiling）, the upper part is relatively small and the lower part is big relatively. The upper part is air-blower room and the air-blower is in it. The lower part is drying room and is used for storing timbers. The surface area of second-storied shed is smaller than that of the ceiling of the kiln because reserving 0.8—1.0 meter’s wind channel separately on the front and at the back of the kiln or on the left and right of the kiln. The radiator is fixed above the wind channel in the second-storied shed. The wind blows from one side air-blower after being heated by the radiator. The airflow blows into the timber stacks from one side wind channel to the other side , then it flows towards the other side air-blower, forming airflow circulation in the kiln, making the timbers be heated and dried. Additionally, it is possible to change the circulatory direction of the airflow in the kiln at regular time by way of the change of the positive-going and reversion of the air-blower, guaranteeing the timbers in the kiln be dried evenly.
VIII. Humidifying Device
On the top of the drying kiln (outside the kiln), there are several groups of air inlet and outlet tube in front of the air-blower and behind. aluminum turnover panel is fixed in the middle of the tube . the moisture produced during the timbers are dried ,when the moistness surpasses the setting value, the adjusting the built-in auxiliary switch will open the turnover panel, adjusting moistness through air inlet or outlet tube , and absorbing in fresh air from air-inlet outside of the kiln, driving out the moisture and realizing the exchange of the dry and wet.
IX. Control System
This kiln has two types of control systems. They are semiautomatic control and full-automatic control，Which change the temperature and humidity inside the drying kiln by meter display and controls of the switch of the valve. Control of temperature is realized by the change of the amount of steam sent to the radiator; control of humidity is realized by spraying or adjusting moisture; at the regular time the direction-changes of the air-blower are realized by changing the phase-sequence of the three-phase power supply of driving motor. Semiautomatic control is realized by operator adjusting the figure of temperature and humidity according to the drying technology of certain period of timber drying process. Operators should master some technology of drying timber and have responsibility. Full-automatic control is realized by computer system, checking automatically and controlling the temperature, equilibrium moisture content, timber moisture content in the kiln. Operators can use keyboard to input or choose directly timer-drying technology stored in the computer, then the computer will run according to the drying technology inputted or selected. During the drying process, it is possible to adjust drying parameter manually at any time if it needs, satisfying different demands.