Component failure of flash drying equipment and introduction of mould temperature machine

The introduction of flash dryer's component failure and mold temperature machine continuous operation of flash dryer, heat and mass transfer and convection drying process at the same time The filter cake of the filter press is pushed into the population in the middle and lower part of the dryer by the screw, falling to the area of the upper dispersing blade of the high-speed rotation, which is quickly crushed, and contacts with the rotating and rising hot air for convective heat exchange With the heating evaporation and the bottom blade crushing, the particle size becomes smaller, and then moves upward in a spiral shape with the rotating air flow, while conveying and drying, the small particles with the required particle size and moisture content are brought out of the dryer with the air flow The inner diameter of flash dryer in this test is 1.65m, the design output is 1.5t/h, and the main motor is 37KW The main problem is that the output is lower than the design value, and it can run stably in the range of 0.6-0.8t/h When it is mentioned above 0.8, the current starts to rise sharply and jump violently until it trips and crashes The current of the main engine changes with the feeding quantity It can be seen from figure L that the average current of the main engine is not high and far from the rated current (72.) However, when the feeding amount increases to more than 0.8t/h, the current starts to beat, and the amplitude becomes larger and larger The change time is less than 1s, and the longer the time is, the larger the amplitude is At this time, the manhole of the main engine cylinder is opened for inspection, and it is found that the bottom material is about 50, and the particle size range is 1-5mm It can be started again after clearing the accumulated materials From the above analysis, it can be inferred that the flash dryer: after the increase of the feeding amount, the current will jump and trip, indicating that the load of the main engine changes greatly As shown in Figure 2, the structure of the main engine dispersion device is divided into three parts: upper part, middle part and lower part Upper part: the upper blade of the high-speed rotating dispersion device is mainly used to crush the paste material into small pieces After trip and stop, check that there is no big block of deposited material at the bottom, indicating that there is no problem here Middle part: the load on the middle blade of the main engine disperser is mainly powder suspended in the middle of the cylinder, so the load is not large Lower part: after tripping and stopping, it is found that there is a lot of material at the bottom, and the resistance is great when manually turning the motor pulley However, after a part of the material is removed (30%), the motor can be turned and the main engine can be started At this time, the operation is normal, and the current is only about 3oa It means that only increasing the resistance of 20kg material can cause the current overload of the main engine to stop It can be concluded that the large load of bottom blade is the main reason of motor trip and shutdown After the paste material is broken by the upper and middle parts of the loose leaves, the particle diameter gradually decreases and falls to the bottom of the broken fluidization section The hot air moves upward along the tangent direction to produce floating effect on small particles The angle of the inverted cone at the bottom is small After the hot air passes through the annular gap, the ventilation cross-section area expands rapidly and the air speed decreases (see Fig 3 for the change of ventilation cross-section area and no-load air speed at different heights from the bottom up) It is not enough to blow the crushed small particles to the middle part for further crushing and drying With the increase of the feeding amount, more and more particles are deposited at the bottom The load of dispersed blade at the bottom increases, resulting in overload shutdown In addition, the outer end of the lower blade extends to the plenum Put the materials into the air collecting chamber to block the air duct When parking, the induced draft is stopped, and the main engine and blades are still rotating depending on the inertia, hitting the air duct and hot blast stove with materials and dust, overflowing from the air inlet, polluting the equipment and environment Here is another kind of equipment die temperature machine, also called die temperature control machine, which is widely used in plastic molding, light guide plate die-casting, rubber tires, rollers, chemical reaction kettle, bonding, internal mixing and other industries In a broad sense, it is called temperature control equipment, which includes two aspects of temperature control: heating and freezing Mold temperature machine is widely used in the plastic industry Its main functions are: to improve the molding efficiency of products; to reduce the production of defective products; to improve the appearance of products and suppress the defects of products; to speed up the production progress, reduce energy consumption and save energy The application of die temperature machine in die casting industry also has a lot of space, especially in the manufacturing of magnesium alloy and aluminum alloy, the uneven or improper die temperature will lead to the instability of the casting size, the casting deformation during the production process, resulting in defects such as hot pressure, mould sticking, surface depression, internal shrinkage cavity and hot bubble It also affects the production cycle, such as filling time, cooling time and spraying time The service life of the die will also be impacted by supercooling and overheating, which will lead to hot cracking of expensive steel and accelerate its aging In the modern factory, it is urgent to save manpower, improve quality and reduce cost in response to the market competition The use of mould temperature machine can reduce the preheating time of mould, improve the surface quality of finished products and fully automate production It is necessary to improve the life of die to improve the productivity.