Lubricant Analysis

Overview

Engine lubricants play an important role in lubrication, cooling, cleaning, and rust prevention for vehicles, construction machinery, ships, airplanes, and other equipment with internal combustion or turbine engines. As the lubricant deteriorates through use, its performance will decline and the inside of the engine can wear, leading to a decrease in service life and potential malfunction.
Lubricants deteriorate due to decomposition and chemical changes of oil components and additives caused by physical and thermal stresses, as well as contamination by metal wear particles and incorporated fuel. Therefore, it is recommended to analyze the lubricant throughout its lifespan to assess its quality, utility, and remaining service life. These analyses can be accomplished with a number of instruments.

Typical causes of engine lubricant deterioration

Analytical Techniques

Lubricant Deterioration Analysis Using FT-IR
Fuel Dilution of Lubricants by GC
Analysis of Additive Elements, Wear Metals

Examples of ASTM Lubricant Analysis Methods

Analysis items (Elements)		Needed system	Standards
Deterioration	Oxidation	FT-IR	ASTM E2412
	Nitration
	Sulfate by-products
Contamination	Water	FT-IR	ASTM E2412
	Soot	FT-IR	ASTM E2412
	Gasoline	GC	ASTM D3525 ASTM D7593
	Gasoline	FT-IR	ASTM E2412
	Diesel	GC	ASTM D3525 ASTM D7593
	Diesel	FT-IR	ASTM E2412
	Coolant (B, Na, K)	ICP-AES	ASTM D5185
	Coolant (B, Na, K)	FT-IR	ASTM E2412
	Antifreeze (Na)	ICP-AES	ASTM D5185
	Dust (Si)
	Seal materials (Si)
Wear	Metals (Al, Fe, Cu, Cr, Ni, Zn, etc.)	ICP-AES	ASTM D5185
Additives	Anti-oxidant (Zn, Cu, B)	ICP-AES	ASTM D4951
	Anti-oxidant (Zn, Cu, B)	FT-IR	ASTM E2412
	Anti-wear agents (B, Cu, K, S, Zn, etc.)	ICP-AES	ASTM D4951
	Anti-wear agents (B, Cu, K, S, Zn, etc.)	FT-IR	ASTM E2412
	Detergent inhibitors (Ba, Mg, Ca, etc.)	ICP-AES	ASTM D4951
	Corrosion inhibitors (Ba, Zn)
	Anti-rusting agents (K, Ba)
	Friction modifier additives (Mo)