Abstract: The invention relates to a method of producing a device or an element belonging to a piece of equipment that is made from steel or a steel alloy, which may come into contact with pressurised oxygen during the use thereof. The inventive method consists in producing a coating by thermally spraying a spray material that is selected from among nickel and the alloys of copper and nickel on at least part of the surface of the element or device, such as to obtain at least one coating layer on said surface, having a thickness of less than or equal to 5 mm.

Abstract: In this pump, each sealing ring (14) of the piston (2) consists of two juxtaposed elementary rings (19A, 19B), the gaps of which are straight or angled and are offset, when fitting them, 180° with respect to one another, and of a common expander (21), and the elementary rings are made of a composite which contains more than 50% bronze and about 5% molybdenum disulphide, the rest being PTFE.

Abstract: Atmospheric air passes through a droplet separator and then through one or more filtration stages. The first filtration stage is made of bag-filter elements with filter medium made up of synthetic fibres with a density which increases in the direction of air flow. The air is introduced thereinto at its natural temperature when between approximately −20° C. and +5° C.

Abstract: The atmospheric air possibly passes through a droplet separator (3) then passes through one or more filtration stages (5, 6). For the or the first filtration stage (5), use is made of bag-filter elements the filter medium of which is made up of synthetic fibers with a density which increases in the direction of flow of the air through this medium. The air is introduced thereinto at its natural temperature when this is between −20° C. and +5° C. approximately, outside of periods of freezing fog, supercooled rain or snow.