The Analysis And Structural Optimization Of The Crankshaft Based On Finite Element Method

Crankshaft is one of the most critical parts in reciprocating pump dynamic section, its reliability directly affect the economy, reliability, and service life of the machine. With the development of power intensity and intensification of the reciprocating pump, the work condition of the crankshaft will become more and more harsh. So the analysis and structural optimization of the crankshaft plays a key role in design and progress of the dynamic part of the reciprocating pump.There are many reasons affect the overall performance of the crankshaft, because its complex geometry and serious stress concentration phenomenon. And failure examples show that the main failure form is fatigue failure which caused by the alternate load though connecting rod plays on the crank bin. In the recent 20 years, study of pump crankshaft strength has been getting great progress with the improvement of computing technology and persisting effort of many researchers, especially in the aspect of calculation of crankshaft stress.Diaphragm reciprocating pump is a high-tech product, with the prominent characteristics of no leakage. At present, the domestic pump industry is paying more and more attention on the diaphragm pump products research. This paper takes model 6DM-100/1.0 diaphragm pump as an example which was used in Jiangsu Sopo Group of 600,000 tons/year acetic acid project, and will take advantage of different ways to the crankshaft which bears a two-way load for dynamic and static mechanical analysis and structural optimization. The detailed contents as follow:1. The load analysis of the crankshaft: comparative analysis will be made between the one-way load and the two-way load of crankshaft, and point out the differences between. 2. The stress analysis and calculation of the crankshaft: analyze the stress with continuous beam method of the one-piece crankshaft in model 6DM -100/1.0 diaphragm pump, and calculate the bending moment of support and the force of crank bin which provide boundary conditions for the three-dimensional analysis with finite element method.3. The stress and modal analysis of the one-piece crankshaft: create the modal of the double action one-piece crankshaft by the software Solidworks, and analyze its stress after import into software ANSYS. Under the method of Block Lanczos in software ANSYS, comparatively analyze modals among the structures of two supports, three supports and four supports of the three-throw crankshaft.4. Propose a new type of assembled crankshaft with few supports: based on defects of the traditional one-piece crankshaft, the paper introduces a new type of assembled crankshaft structure, and will give details of it.5. Virtual prototype simulation and physical prototype tests: comparatively analyze stress and modal of the traditional one-piece crankshaft and new assembled structure, and verify the advantage of the new one under the help of software ADAMS after virtual prototype simulation. Besides, the physical prototype of model 6DM -100/1.0 diaphragm reciprocating pump will be tested to determine its relevant performance parameters under normal operating conditions.