Abstract: Obtaining a piston blank by forging a mass of metal. The metal mass is forged in a hollow anvil using a punch to chase said metal mass into an annular zone thereof while also forming a projection that projects from the center of a base, the punch including an open cavity suitable for giving rise to said projection. The projection is subsequently machined so as to include a bore suitable for receiving a hinge pin for a connecting rod.

Abstract: Apparatus for detecting degradation of the lubrication conditions of smooth bearings connecting a crank shaft to a connecting rod or connecting the crank shaft to the body of a machine that reciprocates in operation, lubrication being provided by oil circulation, the apparatus including means for detecting the phenomenon of seizure, wherein the apparatus comprises an additional bearing serving as a test bearing, said test bearing being lubricated by circulation of the same oil as is used for the other bearings and supporting a radially-loaded rotating shaft, said detection means being fitted to the test bearing which also includes means enabling it to be more sensitive than the other bearings to degraded lubrication conditions.

Abstract: An internal combustion engine for propelling ships that transport gaseous fuel, the engine comprising two groups of cylinders, a first group which is always fed with the same fuel, and a second group which is fed selectively either with said same fuel or else with a different fuel. The invention is applicable to methane tankers.