Research On Theory And Technology Of Health Maintenance For Large-scale Rotary Kiln With Multi-support

Rotary kiln is a key equipment in the metallurgy, chemistry and architectural material. Once stop will bring interruption to the whole production line, and make a great productivity losses. So safety, efficiency and healthiness operation is the key-point to advance benefit of the enterprise.Kiln always have weight of kiloton, length of hectometer and four to nine supporting aprons. It is a statically indeterminate system with heavy load, large torque and multi-supporting mechanism. Because of the axis variations in operating, which leads to the loads distributed hardly equally, sorts of accidents related to mechanical failures and safety happen.To the problem, aim at forming the theory and method to maintain equipments according to the kiln's health conditions, and the relation between axis and its movement, force, strength, and fatigue has been studied deeply. As well as axis measurement, axis adjustment, and broken-axle diagnoses are all studied.Starting from studying the statically beam with complex-load and variable-stiffness, a procedure method to solve the supporting-load distribution is obtained. A linear formula about wheel is derived. Some conclusions are gained. Load distribution bears linear to axis deviation. The middle deviation influence load distribution mostly. The vertical deviation influence load distributions on every apron while horizontal influence on side wheel.Using the software of ANSYS, the dissertation studies the stress distribution of the supporting wheel, the roll and the body. The relation between its magnitude and the load on them is also studied. The study shows: for the wheel, the largest stress is on the middle cross-section, ambient stress distribute in pulsation that is independent of load while the maximum bear linear to it. For the roll, the stress is in multi-varying pulsation, which is independent of load, but its amplitude bears on it, and the largest stress bearing linear on both load and ratio of load is on the inside. About enclose, ambient stress is more larger then axial stress. Much difference exists on the surface. The maximum ambient stress is near the supporting while the less is far from them, but the axial stress quit the reverse.Applying the contact mechanics and the micro-mechanics of elastic slide, axial direction speed formula to calculation the elastic deformations on the surface of contact is derived. The principle and method to control axial direction movement about deflected wheel's variable friction are set forth. The speed model and speed control formula are obtained. And some conclusions are as the follows. In the surface of contact tangential, strain difference will lead to elastic slide. The transmission friction will lead to ambient slide while the slide stress leading to axial slide. The speed bears direct proportion relationship to load's square. Single-valued minus function to coefficient of friction. Axial slid speed is general 200mm/h. When coefficient of friction is in available range of 0.05-0.3, skid speeds variation is over 10mm/h.The equipment health maintenance modal of kiln combined status maintenance with prediction maintenance is proposed. The relation modal between main subassembly's fatigue damage and life with axis is set up, and research the method to prediction its life. Some conclusions are obtained. The wheel axis's equal stress bears line relationship to load. The roller 's equivalent stress in a circle bears line relationship to axis. The kiln main subassembly's fatigue damage and life bears functional relationship to load. So health state can be mastered and predicted from detecting the kiln's axis.The new concept of optimization adjustment kiln is presented combining with the instance of production. It is studied that the supporting system's equal load, the main subassembly's equal strength and equal life .It shows that general method is blind however the optimization method of the rotary can operate well.By synthesis the above investigation, three sorts of axis detection methods are invented, such as time-dom...