| 摘要 |
<p>A hydraulic control system with a pipeline antiburst safety device for a double acting drive cylinder, more particularly for adjusting and securing the position of a driven guide roller in the strand guide of a continuous casting plant which exerts an operationally conditioned reaction force, applied by the strand, on the piston of the drive cylinder. To prevent this reaction force causing the guide roller to retract in the event of a pipe burst, the control system substantially comprises a leakage-proof stop valve of cartridge construction disposed close to the drive cylinder and within the main control duct a leakage proof pilot valve situated close to the stop valve and having a spring-biased spool and a pressure retaining accumulator to maintain the pressure in the adjusting cylinder in the event of pressure failure in the main control duct, and a valve spool of the stop valve has three control surfaces and under normal position is in the closed position under the light pressure exerted by a compression spring which pressure can be overcome by an operationally conditioned pressure rise in the drive cylinder but in the event of a pipe burst the pilot valve changes over and momentarily replaces the absent pressure in the main control duct, normally biasing the control surface of the stop valve spool, by the pressure from the pressure retaining accumulator so that the stop valve remains in the closed position.</p> |
