Abstract: To provide a construction machine including a novel preheating unit that can efficiently preheat entire circulation channel where fluid flows, and a preheating method of the construction machine. A bypass channel is arranged in a circulation channel through which the fluid is circulated, this bypass channel is provided with the preheating unit that is formed of a heater and a bypass pump. According to such configuration, even in a state circulation of the fluid may stop in the circulation channel, the fluid can be heated while the fluid is circulated through the bypass channel, and therefore the entire circulation channel can be efficiently preheated. Moreover, since retrofitting to the existing circulation channel is possible, sound versatility can be exerted.

Abstract: To provide a construction machine including a novel preheating unit that can efficiently preheat entire circulation channel where fluid flows, and a preheating method of the construction machine. A bypass channel is arranged in a circulation channel through which the fluid is circulated, this bypass channel is provided with the preheating unit that is formed of a heater and a bypass pump. According to such configuration, even in a state circulation of the fluid may stop in the circulation channel, the fluid can be heated while the fluid is circulated through the bypass channel, and therefore the entire circulation channel can be efficiently preheated. Moreover, since retrofitting to the existing circulation channel is possible, sound versatility can be exerted.

Abstract: Provided is an abnormality detecting device for a construction machine that can estimate an abnormality occurring to a component (engine, pump, etc.) of the construction machine based on the relationship among a plurality of pieces of sensor information and thereby prevent machine failure. A correlation coefficient calculation unit 102 calculates correlation coefficients between time-series sensor values acquired by a plurality of sensors 101. A correlation coefficient comparison unit 103 compares the correlation coefficients and calculates the degree of difference between each correlation coefficient and other correlation coefficients. An abnormality judgment unit 104 judges that an abnormality has occurred to a part related to a sensor when the degree of difference calculated in regard to the sensor exceeds a preset value.

Abstract: Provided is an abnormality detecting device for a construction machine that can estimate an abnormality occurring to a component (engine, pump, etc.) of the construction machine based on the relationship among a plurality of pieces of sensor information and thereby prevent machine failure. A correlation coefficient calculation unit 102 calculates correlation coefficients between time-series sensor values acquired by a plurality of sensors 101. A correlation coefficient comparison unit 103 compares the correlation coefficients and calculates the degree of difference between each correlation coefficient and other correlation coefficients. An abnormality judgment unit 104 judges that an abnormality has occurred to a part related to a sensor when the degree of difference calculated in regard to the sensor exceeds a preset value.