Assessment and Analysis of Performance Characteristics of Selected Locally Manufactured Lubricants (Engine Oils)

Abstract

This study evaluates the performance characteristics of selected engine oils through comprehensive laboratory testing. The oils Oando SAE 20W50, Techno Super XL 20W50, Visco 2000 SAE 20W40, Conoil SAE 40, and AZ SAE 20W50 underwent analysis for viscosity, flash point, pour point, and carbon residue to determine their suitability for internal combustion engines. Viscosity, crucial for minimizing friction and wear, was measured from 24.8°C to 100°C at intervals. Visco 2000 exhibited the most stable viscosity profile (286MPa-s and 21.2 MPa-s at 24.8°C and 100°C, respectively), making it highly suitable across varying temperature conditions. In contrast, Conoil SAE 40, a monograde oil, showed significant viscosity changes (296.8 MPa-s and 15.60 MPa-s at 24.8°C and 100°C, respectively), suggesting limitations in high-temperature environments. Pour points, indicating oil flowability at low temperatures, ranging from -28°C to -15°C, ensuring usability in Nigerian and African climates. Synthetic oils like Visco 2000, with a pour point of -28°C, are preferred for better cold-start performance. Flashpoints are critical for engine safety, ranging from 102°C to 175°C, exceeding operational requirements. Carbon residue levels varied: Visco 2000 showed the lowest residue at 0.60%, indicating cleaner combustion and reduced deposits, while monograde oils like Conoil SAE 40 exhibited higher residues (1.00%). A pressure mapping experiment assessed oil performance using integrated equipment an internal combustion engine, thermocouple, tachometer, and pressure tube. This method provides rapid and effective evaluation by mapping oil pressures in real-time, recommending its adoption for evaluating lubricant effectiveness in local markets. In conclusion, while all tested oils are suitable for internal combustion engines, synthetic oils, notably Visco 2000, demonstrate superior performance across multiple parameters.