In terms of detection methods, the current detection of iron content mainly includes atomic absorption method and atomic emission method. Although the atomic absorption spectroscopy method is accurate, it is slow and complex to operate. The atomic emission spectroscopy method has been widely applied, but it cannot effectively detect large wear particles (whether by rotating disk electrode or inductively coupled plasma). Its insensitivity to large particles can sometimes be fatal in monitoring and diagnosis, because the particles from normal wear of friction pairs are generally <10μm, while metal particles >15μm are generated by abnormal wear.

For the detection of iron particles, the compensatory approach is to increase iron content monitoring by using a ferromagnetic wear analyzer. The ferromagnetic wear analyzer developed by our company is a measuring device based on the principle of electromagnetic induction. The device is equipped with a sensitive electromagnetic coil. When the oil is placed in a magnetic field, the ferromagnetic wear particles in the oil will cause changes in the magnetic field strength. The magnitude of the electromagnetic induction intensity of the coil has a good correlation with the content of ferromagnetic wear particles. It can conveniently and quickly detect the content of ferromagnetic metal debris in lubricating oil, hydraulic oil, and grease, so as to determine the mechanical wear condition.