Wear Element Monitoring by Spectrometric Analysis in Automatic Transmission Bus

Abstract

Heavy duty fleets face many issues regarding lube service intervals, recommended maintenance procedures, and equipment operating costs. Spectrometric analysis is based on the principles of atomic physics whereby an atom emits/absorbs light of a certain wavelength within the ultraviolet and visible region of the energy spectrum if there is an upset in the energy balance within its atomic structure. In this study, transmission fluid samples were taken from automatic transmission gearbox of different mileages. The Atomic Emission Spectroscopy (AES) testing was conducted by using BAIRD MOA spectrometer to detect chemical elements that were present in the transmission fluid. From spectrometric test, wear element concentrations were obtained. The elements traced were phosphorus (P), boron (B), zinc (Zn), magnesium (Mg), calcium (Ca), nickel (Ni), potassium (K), silicon (Si), aluminium (Al), chromium (Cr), copper (Cu), iron (Fe), silver (Ag), tin (Sn) and sodium (Na). These traced elements were grouped into three main categories; group 1 for wear elements with concentration more than 10 ppm (P, B and Zn), group 2 for wear elements with concentration in the range of 0 to 10 ppm (Mg, Ca, Ni, K, Si and Pb) and group 3 for wear elements with concentration less than 0 ppm (Al, Cr, Cu, Fe, Ag, Sn and Na). Based on the results, P which functions as an anti-wear additive has the highest concentration for fresh ATF and is reduced in used lubricant oil.