Abstract: A generally cylindrical restrictor insert for containing an axially movable, apertured restrictive member, housed in a flow control distributor housing of an orifice expansion device used for bi-directionally-flowing pressurized fluid, with a housing passageway being closed off via an annular adaptor flange also having an internal filter, the restrictor insert having a central axial through bore with a plurality of adjoining bore portions defining a central bore cavity, the restrictor insert also having a leading portion, with a frusto-conical front end surface, and intermediate and trailing portions, the latter having a shoulder portion and an annular end face, the restrictive member being located and axially freely movable within a distributor housing central bore cavity, with the restrictor insert, in turn being located, via slip-fit insertion, in a distributor housing central passageway.

Abstract: A universal housing body for a refrigeration expansion device including a movable orifice piston. The body is adapted for interchangeable use with a piston of a first variety having a radial boss portion extending along a first axial distance, L.sub.1, from a forward boss end having an annular sealing surface of a first maximum sealing diameter, d.sub.max1, to a rearward boss end, and a piston of a second variety having a radial boss portion and an annular seal member having a forward surface defining with a rearward end of the boss portion a second axial distance, L.sub.2, therebetween greater than the first axial distance L.sub.1, and having a second minimum sealing diameter, d.sub.min2, greater than d.sub.min1 and less than d.sub.max1. The housing body has an internal fluid passageway extending from a forward end to a rearward end which couplable with a flange end of an associated adapter. An annular valve seat, having an inner diametric extent, d.sub.i, intermediate d.sub.min2 and d.sub.