Abstract: The present invention refers to a connecting rod/piston arrangement for alternative compressor, comprising using at least an intermediate element capable of associating said connecting rod with the piston, wherein both do not radially contact with one another. A process for assembling said connecting rod/piston arrangement for alternative compressor is also disclosed. The connecting rod/piston arrangement for alternative compressor comprises at least a piston (1), at least an intermediate element (2) and at least a connecting rod (3), wherein said piston (1) comprises at least a non-through axial channel (11); said intermediate element (2) comprises at least a through axial channel (21); and said connecting rod (3) comprises at least a connection end (31). In this regard, the intermediate element (2) is securely housed inside the non-through axial channel (11) of piston (1); and said connection end (31) of connecting rod (3) is securely housed inside the through axial channel (21) of intermediate element (2).

Abstract: A sealing assembly, for example a piston ring, for use in harsh environments, e.g., high radiation levels. The piston ring has an annular sealing surface which together with a member forming a radially outer annular cylinder surface, e.g., a cylinder, forms a seal pocket. Received in the seal pocket is an annular seal comprised of a plurality of wraps of at least one strand of a substantially incompressible and inelastic material such as graphite fiber. The assembly further includes a compression ring and compression assembly which compresses the seal body between the support surface and the compression ring to displace the seal body into sealing engagement with the radially inner and outer sealing surfaces.

Abstract: A continuous seal ring member fitted in a ring groove of a piston of a compressor. The seal ring member has a washer-like initial shape with an internal diameter smaller than an outer diameter of the piston, whereby the inner peripheral portion of the seal ring member is expanded when the seal ring member is fitted in the ring groove. The outer peripheral portion of the ring seal member is then axially and inwardly collapsed relative to the inner peripheral portion thereof so that one of the side surfaces of the initial seal ring member constitutes an outer sealing surface for engagement with the cylinder bore and the outer peripheral portion in the original shape is arranged on the side of said compression chamber.

Abstract: The operation of a reciprocating expansion engine for cryogenic refrigeration is improved by changing the pistons and rings so that the piston can be operated from outside the engine to vary the groove in which the piston ring is located. This causes the ring, which is of a flexible material, to be squeezed so that its contact with the wall is subject to external control. This control may be made manually or it may be made automatically in response to instruments that sense the amount of blow-by of the cryogenic fluid and adjust for an optimum blow-by.

Abstract: A mud pump piston comprising an annular elastomeric ring having an annular circumferential surface defining an acute angle circumferential tip of relatively small area which engages the pump cylinder wall and an annular anti-extrusion ring connected to and displaceable with the elastomeric ring, the elastomeric ring being configurated to correspond with and rest against a dish shaped surface of the anti-extrusion ring presenting a bevelled or diagonal slope extending from the outside diameter (acute to the axis of the mud pump piston) spanning substantially more than half of the radial distance occupied by the annular elastomeric ring and the annular anti-extrusion ring, which diagonal surface merges with a flat surface normal to the axis of the mud pump piston whereby hydro-planing is reduced because of the increased unit pressure load on the small tip area, along a line contact, the tip is automatically wear compensating, friction is substantially reduced by reason of the smaller high pressure wipe area, lo