Abstract: An installation for following up the evolution of the quality of a lubricant circulating in equipment includes a conduit connected, upstream, to the piece of equipment and downstream to a recovery pan. A first controlled interruption valve circulates the lubricant in the conduit, a buffer reservoir accumulates lubricant, and a first bypass line is connected to the conduit, upstream from the first valve and to the buffer reservoir. A second controlled interruption valve circulates the lubricant in the first bypass line, a second discharge line discharges the lubricant, from the buffer reservoir to the recovery pan and a third controlled interruption valve circulates the lubricant in the second discharge line. A sensor determines content in a predetermined chemical element of a lubricant sample at the outlet of the buffer reservoir. This sensor includes an X-ray source and detector and a sample cell with a poly X-ray window.

Abstract: This installation for following up the evolution of the quality of a lubricant circulating in a piece of equipment includes a conduit for circulating the lubricant, this conduit connecting upstream equipment and a downstream recovery pan. The installation further includes a first controlled valve for interrupting lubricant circulation in the conduit, a buffer tank accumulating the lubricant, a first bypass line connected to the conduit, upstream from the first valve and to the buffer tank. The installation also includes a second controlled valve for interrupting the circulation of the lubricant in the first bypass line, a second line for discharging the lubricant, from the buffer tank to a recovery pan and a third controlled valve for interrupting the circulation of the lubricants in the second discharge line. A sensor allows determination of the dissolved iron content of an amount of lubricant contained in the buffer tank.

Abstract: This installation (2) for following up the evolution of the basicity of a lubricant circulating in a piece of equipment (M) comprises at least one conduit (4) for circulating (F1) the lubricant, this conduit being connected, upstream, to the piece of equipment (M) and the, downstream, to a recovery pan (6) as well as at least one sensor (48) for determining the basicity index of the lubricant. The installation further comprises a first controlled valve (20) for interrupting the circulation (F1) of the lubricant in the conduit (4), a buffer tank (26) for accumulating the lubricant, a first bypass line (28) connected to the conduit (4), upstream from the first valve (20) on the one hand and to the buffer tank (26) on the other hand.

Abstract: The invention concerns a lubricant for a two-stroke slow speed crosshead marine engine, powered with a fuel with sulfur content not less than 1%, consisting of a mixture of distillates used as lubricating bases containing x wt. % of dispersing additive of the succinimide type, y wt. % of an overbased detergent additive of the sulfonate type, and z wt. % of an overbased detergent additive of the phenate type. The invention is characterized in that x, y and z are selected in the intervals 0.5≦x≦2.5, 2.5≦y≦10 and 11≦z≦24.5 such that 15≦x+y+z≦36 and 1.5≦y/x≦13, the BN of the lubricant, determined according to the ASTM D-2896 standard, is not less than 70 mg KOH/g, and the speed at which sulfuric acid is neutralized by the lubricant, defined by the maximum speed of pressure increase of a closed chamber, with its walls covered with a film of said lubricant from 80 to 100 &mgr;m thick, maintained at 100° C.

Abstract: The invention relates to the study and the manufacture of lubricants used in particular in diesel engines. According to the invention, the neutralization capacity of a lubricant comprising detergent additives is determined by a method which consists in reacting, in a leaktight tank, at a constant temperature, the bases contributed by the additives present in a lubricant film of known mass with a predetermined amount of a liquid acid and in recording, as a function of the time, the values of the pressure within the leaktight tank, and in then determining, from the recorded values of the pressure, at lest one of the following three characterizing parameters: an initiation period for the reaction, a neutralization potential and a reaction rate. The invention finds its application in research and control laboratories of manufacturers of lubricants and in those of engine manufacturers.

Abstract: Fuel compositions containing a major proportion of at least one fuel base and a minor proportion of at least one fulvene derivative, characterized in that the said fulvene derivative is a 5-(alkylalkylidene)-1,3-cyclopentadiene of formula (I) below: ##STR1## where R.sub.1 is the hydrogen atom or an alkyl group containing from one to three carbon atoms and R.sub.2 is a hydrogen atom or a saturated or unsaturated aliphatic group containing from one to four carbon atoms. Use of the fuel compositions in reciprocating engines with spark ignition and turbine and jet engines.

Abstract: This invention relates to superbasic additives for lubricant oils containing an organic molybdenum complex virtually insoluble in hydrocarbons. The complexes are formed with organic compounds such as amines, diamines, alkoxylated amines, glycols and polyols.The additives according to the invention have anti-wear, friction-reducing and antioxidant properties in the lubricant formulations.