Technical Article

Design and analysis of the ball joint structure of the main cylinder of the fast forging hydraulic p

The fast forging press is an indispensable mother machine in the automation production process of the forging industry, which plays a very important role in improving productivity, improving production conditions, reducing labor intensity, and enhancing forging quality. The rationality, strength, and lifespan of the structural design of the working cylinder, as the power execution component of high-precision and intelligent large-scale forging equipment, determine the overall performance of the machine. In the process of free forging, the forging working environment is harsh, and the working cylinder is not only subjected to compressive stress from the hydraulic system, but also to lateral thrust, thermal stress, friction, etc. caused by partial load. Sometimes, it may even be subjected to certain impact forces, resulting in plunger pulling, hydraulic cylinder sealing, guide sleeve damage, and even destruction, seriously affecting the performance of the working cylinder. In order to reduce the damage caused by unbalanced load to the main cylinder seal, guide sleeve, etc., the current main cylinder plunger connection structure mainly adopts a double ball joint structure. Through a detailed and in-depth study of the design parameters of the ball joint structure on the anti eccentric load capacity of the main cylinder and its influence on the lateral thrust of the guide sleeve and seal, the following conclusions have been drawn:

(1) The maximum opening angle in the design parameters of the ball joint structure determines the anti eccentric load capacity and stress situation of the ball joint.

(2) The relationship between the radius of the ball joint friction circle, the friction torque acting on the ball joint, and the maximum opening angle of the sphere is a cosine like curve, and both fluctuate periodically with an increase in the maximum opening angle of the sphere, with a fluctuation period of about 10 ° and a stable fluctuation opening angle range of about 5 °.

(3) Under off load conditions, the radial thrust of the plunger on the guide sleeve and seal also exhibits a cosine like curve pattern, and fluctuates periodically with the increase of the maximum spherical angle, with a fluctuation period of about 10 ° and a stable fluctuation angle range of about 5 °.