Liu Shuxun and others of Huazhong University of Science and Technology have carried out research on the phenomenon that the matching clearance of hydraulic sliding valve is too small, and the valve body and spool are deformed under the action of pressure, temperature and other loads, which is very easy to cause the spool to get stuck in the working process, thus causing the valve to fail suddenly.The matching clearance between body and spool of two-position four-way change-over spool valve with large diameter is studied and analyzed by means of thermal-structural coupling method. Under different operating conditions, the wall thickness and initial matching clearance of the valve body are optimized, in order to guarantee the strength of the valve body and avoid the spool jamming, at the same time, to ensure the reduction of leakage loss.The feasibility of the optimization design method is verified by a prototype, which provides certain theoretical basis for the design and development of large-diameter hydraulic sliding valve.
Liu Xinqiang of Lanzhou University of Technology and Yin Sheng of Zhongnan University analyzed the stress and strain of integral multi-way valve used in excavator under different working conditions by fluid-solid coupling method. The result shows that the deformation of valve body mainly occurs at the corner of the oil confluence window leading to the actuating mechanism; and the stress concentration is obvious at the corner of each flow channel and at the high-pressure oil port.Both stress and deformation increase with increasing flow field pressure in the valve.
Qin Tao of Jili Automotive Research Institute takes the hydraulic valve body of double clutch automatic transmission as the research object, establishes finite element models of upper valve body and lower valve body respectively from the angle of strength check, applies uniform load in the oil duct, obtains stress distribution and stress concentration point on the wall of each oil duct, and lightly designs the hydraulic valve body according to the calculation results.