Break-line Mode Valve Operation in Large Oil Hydraulic Systems

Abstract

Oil column separation in the return line of a large oil hydraulic system is studied analytically, and the relation between the valve operation of the break-line mode and the rejoin surge pressure is investigated. The valve operation of the break-line mode, which has a lower operation speed near the closing point, shortens the valve closing time without increasing the rejoin surge pressure following the oil column separation. There is a region of the dimensionless valve opening corresponding to the break point of the valve operation, in which the rejoin surge pressure is lowered. The critical value of this region depends upon the dimensionless parameters which describe the return line. The result obtained in this study is available for the design of the breakline mode valve operation which shortens the valve closing time.