What are the common faults of tube bundle dryers?

1. Fault of reduced heat transfer efficiency
Tube bundle scaling problem
Reason: During long-term use, scale may form on the surface of the tube bundle due to impurities, minerals and other components in the material. For example, when processing aqueous solution materials containing calcium and magnesium ions, as the water evaporates, these ions may precipitate on the surface of the tube bundle to form scale. In addition, some sticky components in the material may also adhere to the surface of the tube bundle, gradually accumulating to form a scale layer.
Impact: Scaling will increase thermal resistance and reduce the thermal conductivity of the tube bundle. The heat of the heat medium is difficult to effectively transfer to the material side, resulting in a decrease in drying efficiency. For example, if the scaling thickness on the surface of the tube bundle reaches 1-2mm, the heat transfer coefficient may decrease by 30%-50%, which significantly prolongs the material drying time.
Tube bundle corrosion problem
Reason: If the dried material is corrosive or in a high temperature and high humidity environment, the tube bundle may corrode. For example, when processing acidic chemical raw materials, acidic substances will chemically react with the metal materials of the tube bundle and destroy the surface structure of the tube bundle. At the same time, when the protective coating on the surface of the tube bundle is damaged, it is also easy to cause corrosion.
Impact: Corrosion will make the tube wall of the tube bundle thinner, reducing its thermal conductivity and mechanical strength. Severe corrosion may cause perforation of the tube bundle and leakage of heat medium, which will not only affect the drying effect, but also cause safety hazards.
2. Mechanical failure
Tube bundle rotation problem
Transmission component failure: Wear and breakage of the transmission chain or gear are common reasons for the failure of the tube bundle to rotate normally. For example, due to long-term exposure to large torque and friction, the links of the transmission chain may wear, become loose, jump teeth or even break. In addition, wear on the tooth surface of the gear and broken gear teeth will also affect the transmission of power, making the tube bundle unable to rotate or unstable.
Bearing failure: The bearing is a key component that supports the rotation of the tube bundle, and its damage will cause the rotation of the tube bundle to be blocked. The bearing may be damaged due to long-term overload, poor lubrication or entry of foreign matter. For example, when the ball of the bearing is worn, the inner and outer rings are broken, or the retainer is damaged, the tube bundle will be stuck and vibrated during rotation, affecting the turning and drying effect of the material.
Cylinder sealing problem
Reason: The seals between the cylinder and the feed port, discharge port, and exhaust port may age, wear, or be damaged after long-term use. For example, the sealing rubber ring is prone to aging and hardening in a high temperature environment, losing elasticity, resulting in a decrease in sealing performance. In addition, the flushing of materials may also damage the seals.
Impact: Poor sealing will cause heat loss inside the dryer and reduce drying efficiency. At the same time, it may also cause material leakage, resulting in waste and environmental pollution.
3. Material flow problem
Material blockage failure
Feed port blockage: If the particle size distribution of the material is uneven or contains too large lumps, it may be blocked at the feed port. In addition, if the feed speed is too fast and exceeds the normal flow speed of the material in the cylinder, it will also cause the feed port to be blocked. For example, when processing materials containing fibers, the fibers are easy to entangle together and block the feed channel.
Cylinder blockage: In the cylinder, if the humidity of the material is too high, it is easy to form agglomeration and block between the tube bundles or in the corners of the cylinder. Moreover, when the tube bundle rotates too slowly, the material cannot be effectively turned over, which may also cause blockage. Material blockage will prevent the drying process from proceeding normally and affect production efficiency.
Uneven material distribution problem
Causes: Factors such as improper tube bundle rotation speed, unreasonable feeding method or internal structural design defects of the cylinder may cause uneven distribution of materials in the cylinder. For example, if the feed port position is set unreasonably, the material may be concentrated on one side of the cylinder and cannot fully contact the tube bundle.
Impact: Uneven material distribution will cause some tube bundles to fail to fully exert their drying effect and reduce drying efficiency. At the same time, it will also affect the drying quality of the material, making the moisture content of the dried material inconsistent.