1.故障现象1台中联重科23t挖掘机工作时发动机“掉速”严重,且排气管冒黑烟,经观察明显感觉发动机过载,即出现“憋车”现象;而空载时动作却基本正常。分析认为,可能是发动机进气不畅,或者主液压泵功率控制系统有故障。为此我们依据该型挖掘机功率控制原理,进行以下分析及排查。2.工作原理该型挖掘机采用双泵双回路负流量 1. Symptom 1 SZ Zoomlion 23t excavator working “engine speed” serious, and the exhaust pipe black smoke, the engine obviously over-observed the feeling of overload, that is, Load time is basically normal. Analysis, may be poor engine intake, or main hydraulic pump power control system failure. To this end we based on the principle of excavator power control, the following analysis and troubleshooting. 2. The working principle of this type of excavator double pump dual negative flow