| 摘要 |
PROBLEM TO BE SOLVED: To provide a rock hopper improving reliability while preventing lowering in operation efficiency. SOLUTION: When both valves 6, 7 provided on a discharging passage 20 of solid matter B so as to open/close are closed, a controlling/determining means 25 controls a pressurizing means 10 (10a) to make pressure P2 of a middle area 8 defined between both valves 6, 7 higher than specified pressure P1 of a pressurizing line 16 upstream to the upstream side valve 6. On the basis of the pressure P2 of the middle area 8 detected by a pressure detecting means 9 at a series of alternately opening/closing both valves 6, 7, the presence or absence of leakage from the upstream and downstream valves 6, 7 is determined, and the presence or absence of the leakage of the valves 6, 7 can be simultaneously detected with discharging the solid matter B without stopping discharging.
|
