WEARING METALS AND THEIR RESPECTIVE PARTS IN DIESEL LOCOMOTIVE

INTRODUCTION

Lube oil analysis of Diesel locomotive by using several  analytical techniques for the condition monitoring and monetizing the engine is very important for the long life of the engine. The analytical techniques involves techniques such as elemental analysis by RDE-AES or ICP-AES , Fourier transform infrared spectroscopy, Viscosity measurement , Particle counting wear debris analysis and Karl Fischer moisture. However we had discussed about some of the above analytical techniques in earlier posts and rest of the techniques we will discuss in upcoming post. In this post we are going to discuss about the wear metals and their respective affected parts.

Elemental analysis is the most basic tests for the lube oil analysis, it is used to determine the presence of wear metals in diesel oil locomotives. There are two types of instruments which are generally used for the elemental analysis of lube oils , "RDE-AES & ICP-AES" ,which can detect more than 20 elements in lube oil. We will discuss in detail about the differences between both the instrument in the upcoming posts, however in the mean time they serve the same purpose of determination of wear metals in PPM level inside the lube oil .

During machinery in working , wear metal debris particles are produced by rubbing motion of mechanical component parts , are either normal wear or abnormal wear, these wearing metals can be detected using spectroscopy . The wear metals indicate their respective sources i.e engine parts. For every diesel engines certain limits are set for respective metals in ppm ,above which failure may occur because of the higher rate of wearing. So using spectroscopy it is much easier to monitor the condition and can take appropriate action before it will be too late and can save from bigger loss.

BELOW IS THE LIST OF THE WEAR METALS AND THEIR RESPECTIVE SOURCES:

WEAR METAL	SOURCES
Aluminium	Piston, inappropriate filtrations, Crankcases on Reciprocating Engines, Bearing Surfaces, Pumps, Thrust Washers.
Copper	Bushing, Thrust Plates.
Silicon	Inappropriate air filtrations.
Iron	Bushing, Shaft, Ring.
Chromium	Cylinder liner, Exhaust Valves.
Tin	Main bearing, Con rod, TSC bearing.
Lead	Con road, TSC bearing, Seals, Solder, Grease.
Sodium	Water coolant leakage into oil.
Boron	Water coolant Leakage.
Magnesium	Oil additives.
Nickel	Alloy from bearing metals.
Molybdenum	Piston rings.
Phosphorous	Anti-wear additive.
Potassium	Coolant Leak, Airborne Contaminant.
Silver	Bearing cages ( Silver Plating ).
Zinc	Anti-wear additive.
Calcium	Detergent Dispersant Additive.
Barium	Synthetic Oil Additive Synthetic Fluid.