Internal Leakage Analysis of High Voltage Circuit Breaker Hydraulic Actuator Pilot Valve Oil Sealing Part and Leakage Prevention Method by Preliminary Deformation

While the high voltage circuit breaker hydraulic actuator valves open and close for a very short period of time (-ms), the pilot valve sealing failure which open close at first, and the behavior of the oil-sealing according to repeated loads wer analyzed. As a very high impact load is applied when opening and closing the oil-sealing part, cracks in the oil-sealing part or uneven deformation between the parts forming the oil-sealing part may occur, and unnecessary maintenance costs may occur due to the failure of the oil-sealing part. To prevent this, the convergence value of the oil -sealing deformation according to the repeated impact load of the oil-sealing portion was checked, and a method was developed and demonstrated to prevent internal leakage by applying a preload to the oil-sealing portion.