Abstract: An apparatus for chilling and shrinking workpieces being conveyed to a workstation on an assembly line comprises, a chilling chamber, a conveyer for transporting workpieces, at least one generally vertical conduit for transporting cryogenic liquid out of a bath to an outlet above the bath, wells for storing cryogenic fluid bath, baffles for slowing the counterflow of cryogenic vapor and a lid for maintaining vapor in the chilling chamber. The workpieces first go through the pre-cooling process where cryogenic vapor flows in a counterflow to chill the workpieces. The workpieces move through openings in the baffles, and after the pre-cooling process, the conveyer transports the workpieces to the cooling stage where baths of cryogenic liquid are stored in wells. Generally vertical conduits are immersed in the wells. The density of cryogenic fluid in the conduit is reduced by warm vapor, enabling the cryogen to flow up the conduit.

Abstract: Liquid cryogen is added to a container of particulate material (e.g. powder, flakes or granules) immediately before the container is capped as part of a process for pressurizing the container. A liquid cryogen retainer is positioned within the unsealed container above the particulate material, and the flow of liquid cryogen is directed to the retainer to substantially prevent eruption from the container of the particulate material, which may otherwise result when the liquid nitrogen penetrates the particulate material and causes the particulate material to erupt, with an unacceptable loss of the particulate material and of the liquid cryogen.

Abstract: Workpieces (e.g. valve seats, valve guides, or cylinder liners for an internal combustion engine) are chilled as they are supplied to a station on an assembly line, using a feeder/chiller that includes a passage to convey workpieces downwardly from a location at the top of the passage to an assembly line station. The chiller/feeder is fed cryogen from a reservoir of liquid cryogen. Because cryogen fluid (chilled nitrogen vapor) entering the passage is denser than air, downward flow of cryogen fluid must be restricted. For example, the passage includes a constriction below the position at which cryogen is fed to the passage. The constriction is configured and sized to allow workpieces to move through the constriction, yet the constriction is small enough to restrict the downward flow of cryogenic fluid when a workpiece is positioned in the constriction. Above the constriction, the cooling passage is large enough to allow sufficient clearance around workpieces to permit an upward flow of cryogenic fluid.