Determination of structural and dimensional changes of rubber seals immersed in oil

Abstract

The purpose of this work is to investigate the suitability use of vegetable-based oil in hydraulic system and the compatibility between the rubber seals and lubricant extracted from vegetable-based oil in hydraulic system. Two types of o-ring rubber seals were used which are Fluoroelastomer (VITON) and Nitrile Rubber (NBR). These rubber seals were fully immersed in two different types of oil, which are Seri Murni Palm Olein Oil and Pennzoil 68 Hydraulic Oil for two months. Detailed analysis on the rubber seals mass, thickness and perimeter, swelling test, Secondary Electron Microscope (SEM) test and oxidation test were done during the study period in order to investigate the dimensional and structural changes of rubber seals. The viscosities of immersed oils were also tested to analyze its impact on the physical changes on seals. The analysis was done using the ASTM standard method. Result shows that the Seri Murni Palm Olein Oil has the potential to be used as hydraulic fluid especially when using with VITON seal. However, some of physical and its chemical properties need to be enhanced first by adding additives to the olein in order to improve the effectiveness of the vegetable based oil as hydraulic fluid.