Design And Practice Of Engineering Projects Incomplete Sets Of Engine Cylinder Head

Engine cylinder head is one of the key parts of the engine, which is used to seal and constitutes the combustion chamber of the cylinder box-type parts. The cylinder head belongs to the gas distribution mechanism in internal combustion engine, it supports the camshaft, trocker shaft, intake pipe and outtake pipe. First, in the aspect of machining process improvement, through the process of dispersed to concentrated, by using common tool machining to compound multi- blade cutting tool, reducing the number of machining centers, and reducing the positioning error caused by multiple repeat positioning, and give full play to the role of processing center; Second, the fixture clamping cylinder head using a plane and two pits, six degrees of freedom in space is fully positioned, the location of four supporting nail surface forms a support surface, which limit cylinder head moving along the Z axis and rotating around the X, Y axis, round pin limits X, Y axis movement, edge cutting pin limits rotation around the Z axis, the above measures are in order to ensure the positioning accuracy of cylinder head. In the aspect of automatic orientation device for fixture, hydraulic cylinder and the guide column to form an automatic feeding mechanism, in the process of supporting plate falling in, the workpiece has been positioned in the rear position of the supporting mechanism, combined with the taper of end of the locating pin, the self- looking and self- locating of the cylinder block is realized; In the end, the project evaluation model is obtained by using the reference of similar projects and experts for many years. The combination of AHP and fuzzy comprehensive evaluation method is used to evaluate the implementation of the project.The problem to be solved in this paper is as follows: From the project process design to the specific fixture design, and then to the production line has been completely completed, using integrated method of analytic hierarchy process and fuzzy comprehensive evaluation to evaluate the project evaluation model. Through the comprehensive evaluation results, it can make the project implementation effect have a quantitative criteria. Through the second level evaluation index, we can know that which is better in the target, progress and effectiveness, what aspects to be improved. Through the evaluation results put forward reasonable suggestions, in order to improve the implementation of the project, improve the quality of the project, in order to control the impact of similar projects in the future and the key factors of the whole system.