The Computer Imitation Study On The Pneumatic Impact Hammer

The pneumatic impact hanyner in developing stage is a efficient equipment used in trenchless construction, however, its design theory is very imperfect. In this article, the haniner is taken as the object of study on the basis of analysing the trenchless construction technology and equipment, and is studied with computer imitation technology. The main contents of the study are as follows.(a)After analysing the plan of past pneumatic impact equipment and the structure of impact haniner abroad, a simple and eff{cient design plan of impact hantner is given according to its practical work condition. The qualitative study on the haniner is made.(b)Regarding impact haxrmner and air compressor which offer power for the impact hanmier as a system, the quantitative analysis of the internal dynamic property of the hanuier is carried out with the principle of dynamics and gas dynamics. The process of valve hole being on and off and the influence of the pipelines, through which the air is transported, on the dynamic property of air in t.he haniner are studied. The relation between the mass and pressure of the air in the hanmier and structure parameters of the hanmier is set up. The function parameters of the hanmer are linked with its structure parameters~ the function parameters of air compressor and the size of pipeline through which the air enter the haniner by mathematics formulas, that is, the mathematics model on the internal dynamic process of the haniner is set up.(c)Through the computer imitation study of the dynamic process, the solution of the model is given. Through the imitation analysis of the factors affecting the performance of impact haxmier, the relation between the performance and factors is ascertained.(d)The optimum method on the impact hanmer is obtained by the use of the study result above and optimum theory.(e)Based on the imitation and optimum study, the visual computer adied design program is given with VISUALBACJC language. A precise method is provided for the design and study of impact haniner.(f)The practical application of impact hantner is introduced briefly.