Exhaust gas treatment apparatus for working machine

摘要

An exhaust gas treatment apparatus for a working machine is provided which can reliably prevent a specific process that raises the exhaust temperature of an exhaust gas treatment section from being carried out during switching operation of a directional control valve. An exhaust gas treatment apparatus for a working machine includes: a directional control valve 14 that controls the flow of pressure oil supplied to an actuator 4a that is actuated upon supply of the pressure oil from a hydraulic pump 8; a pilot pump 16 that supplies pressure oil to an operating device 19 operated to switch the directional control valve 14; an open/close valve 13 arranged downstream of the directional control valve 14; a control valve 15 that controls the open/close valve 13; a lock valve 17 arranged between the pilot pump 16 and the operating device 19; a detecting section 12 that detects when a specific process that raises the exhaust temperature of an exhaust gas treatment section 11 becomes necessary, and outputs the corresponding detection signal; a controller 18 that controls the control valve 15; and a pipe 31 for performing a process of setting the open/close valve 13 to an open position 13a in accordance with the pilot pressure oil supplied from the pilot pump 16.