Sealing Structure Analysis And Design For The End Shaft Of Vibrating Concrete Mixer

Double horizontal shaft vibratory concrete mixer, carrying good mixing quality, high production efficiency and many other advantages, has begun to be applied to all types of large cement concrete construction projects. However, the shaft end sealing problems is an important factor of limiting vibratory concrete mixer marketing. There is an urgent need for a new shaft seal structure for vibratory concrete mixer.In this paper, according to the "ask a question- analyze the problem- problem solving" research ideas, using literature analysis, list, contrast, theoretical analysis, simulation analysis and experimental research methods to study concrete mixer dynamic vibration shaft sealing problems. In the analysis stage, firstly, the particularity of the dynamic shaft sealing problems are analyzed, and pointed out the three problems for dynamic shaft sealing structure; then, the sealing structure and principle, the precision manufacturing and storage of parts, the vibration and dynamic balance of mixing shaft system, the deform of mixing shaft system after the force as well as mixing device this five aspects of dynamic sealing technology influence factors were analyzed; finally, the existing dynamic shaft seal technology has been introduced, and its seal structure and principles has been described, and the external manifestations and underlying causes of shaft seal failure has been explored. In structural design phase, in accordance with the "design plans-- program design—structure design" design process, first of all, put forward the design goals and tasks; then, through the "two level evaluation method" the best scheme has been proposed in a number of possible schemes; finally, combined with the enumeration method, comparison method, experience design method, and the system design method p ?V ?T ?h is introduced in theoretical calculation, completed the design of seal structure. After new structure design is finished, dynamic analysis of the new structure and operating state analysis had been done by ABAQUS FEA software. The analysis showed that the front of six natural frequencies of the new structure is 170.14 Hz, 170.17 Hz, 187.04 Hz, 214.97 Hz, 234.67 Hz, 234.75 Hz, which do not coincide with the mixer system excitation frequency, and avoided resonance; elastic damping element is reasonable, and the sealing interface under conventional impact load can maintain the normal working condition; rule of motion is consistent with the actual observation conditions, which can get good stress state. Then, performance test of the new structure has been designed. During the vibratory concrete mixer in the actual production environment continuously 100 h test, the temperature and wear of the shaft end sealing structure are in line with the requirements, none of cement mortar leakage and grease leakage phenomenon has been found. Experimental results show that the shaft end sealing structure have good sealing performance, which can meet the design requirements, and the shaft end sealing structure can be used in industry.