| As a large manufacturing equipment, the pushing double column free forging hydraulic press inevitably appears the state of eccentric load in the forging process that highly demands on the eccentric load resistance. The research on eccentric load resistance of pushing double column forging hydraulic press has great significance to improve the designing and manufacturing capabilities of extreme manufacturing equipment in our country.Main connection form of working cylinders and movable beams in the pushing hydraulic presses are the connection of ball joint structures. Traditionally, the theory analysis of the eccentric load resistance of forging hydraulic press’ ignores the self-locking characteristic of ball join and just centers on the frame. Therefore, it is difficult to effectively reflect transfer route of eccentric forging force, mechanical analysis model of eccentric forge, and constraining factors of the eccentric forging. Furthermore, it causes security danger in the use of hydraulic press. As an important parameter, the eccentric load resistance should be evaluated. Meanwhile, the maximum allowable eccentricity need to be researched under the condition of the self-locking characteristic of forging hydraulic press.According to the condition of “Under the eccentric load, the ball hinge will be locked” a mechanical analysis model of large scale double column free forging hydraulic press’ eccentric forging is built. The self-locking load eccentricity, mechanism and constraining factors of forging hydraulic press in eccentric forging are analyzed. Combined with theoretical analysis and simulation calculation, the eccentric load resistance is researched. A method to determine the maximum allowable forging eccentricity has been proposed. A interstitial fluid model is built based on fluid solid coupling method. More exact and effective results are obtained.. We have proved that eccentric forging force would act on working cylinder by moving the beam of the press, when the ball joint meets its self-locking condition,so the working cylinder is the main control factor of the eccentric load resistance of forging hydraulic press. Ball joint structures can protect forging hydraulic press’ cylinder in the process of no-load & return due to its self-adapt rotating characteristics. It can effectively alleviate the thrust of the working cylinder resulted from the synchronization error of return cylinder. According to the self-locking conditions of forging hydraulic press and analysis results of eccentric load resistance, the maximum allows forging eccentricity of forging hydraulic press is determined. We have put forward the method to improve the eccentric loadresistance and provided basic for the design and optimization of forging hydraulic press machine structure. |
