自由鍛造プレスのもどり管路における油柱分離に関する一考察

抄録

In a large free forging press, the high speed operation of a directional control valve often causes an oil column separation in the return line of the valve. This paper deals with the numerical analysis of the pil column separation in the return line of large oil hydraulic systems caused by the valve stroking of linear mode. The relation between the valve closing time and the rejoinder surge pressure following the oil column separation is investigated in detail. The expression of valve characteristic can be simplified by the use of an effective valve stroke. By introducing dimensionless variables for the basic equations, dimensionless parameters are induced. The oil column separation caused by the valve stroking of linear mode is expressed by using the dimensionless parameters.