OIL PRESSURE TYPE ELEVATOR MODIFICATION METHOD

摘要

PROBLEM TO BE SOLVED: To provide an oil pressure type elevator modification method capable of suppressing man hour and cost of piping work related to additional installation of a duplex check valve to minimum level, and improving reliability and maintainability of the installed duplex check valve.SOLUTION: An internal piping 13 for connecting a control valve unit 20 and a muffler 42 in a power unit 15 of the oil pressure type elevator is replaced to a duplex check valve unit 30 having a duplex check valve 31 and a stop valve 32.