The quantification of trace elements in used lubricating oil is useful for evaluating the wearing of specific components of engines. In the present work, inductively coupled plasma optical emission spectrometry (ICPOES) was used for determining five refractory elements (Ni, Mo, Cr, V and Ti) in lubricating-oil samples. The methodology was developed while aiming at the introduction of such organ...

On 9 October 2001 two US oil companies Chevron and Texaco merged. Their long-term joint venture operation, known as Caltex (formed in 1936 and operating in East and Southern Africa, Middle East, Asia and Australasia), was incorporated into the one global energy company. This global enterprise will be highly competitive across all energy sectors, as the new company brings together a wealth of ta...

Lubricating greases are colloid disperse systems consisting of a base oil and a thickener (additional additives). The lubricant is modeled as a tribological system, and the reaction of a fluid friction stress is investigated. The energetic situation of the volume element is analyzed and the system entropy described. The description of the structural degradation and the used entropy was realized...

Re-refined lubricants have been produced in New Zealand for over 50 years. However, their acceptance as a high quality lubricant has been a gradual process, largely because of the scepticism of the public that the product can be re-refined to its original condition. In New Zealand Dominion Oil rerefines about 7 million litres per year, while an older acid clay method is used at Turua near Thame...

There is an increasing demand for the on-line condition monitoring of lubricating oils. In our recent research, we considered various sensor principles for the on-line monitoring of thermal aging of engine oils. One of the investigated parameters is the viscosity of the lubricating oil, which can be efficiently measured using microacoustic sensors. Compared to conventional viscometers, these se...