Abstract: A pet litter container having a covering defines an interior space. A door opening in the covering allows for pet ingress and egress. A plurality of ventilation openings are provided in the covering. A power filter is located in fluid communication with the ventilation openings for removing and filtering odors from the air in the interior space. The power filter includes a power filter housing having an air inlet and an air outlet. An air path is defined by the power filter housing between the air inlet and the air outlet. A low voltage fan is mounted in the housing in the air path for moving air at a predetermined rate from the interior space, through the air inlet, and out the air outlet for exhausting filtered air from the interior space into an interior room in a house or an apartment. A self-contained filter cartridge is removably mounted in the housing in the air path for removing odors from the air in the air path.

Abstract: An additional barrier for a production tree works in conjunction with a conventional swab barrier. A spool with a bore is mounted on the tree above the swab valve. A tree cap is secured to the top of the spool. The spool has a nipple profile in its bore for receiving a multi-part retrievable plug. The plug is located across the junction between the tree cap and the tree and is wireline retrievable.

Abstract: A refrigerant recovery unit for large refrigerant systems has a suction compressor which withdraws vapor and a liquid pump which withdraws liquid refrigerant. The compressor and liquid pump pass the fluids to a heat exchanger and a condenser, both located within a bath of chilled liquid. The vapor condenses into a liquid and combines with the liquid refrigerant. The liquid passes to a storage tank. A feedback compressor withdraws vapor from the upper portion of the tank if the pressure is above a selected level and passes it to the condenser for further condensation. A bypass line directs refrigerant vapor to the inlet of the feedback compressor if the tank vapor pressure is below the selected level. A drawdown line allows the feedback compressor to draw all of the refrigerant from the recovery unit after the recovery unit has recovered the refrigerant from the refrigeration system.

Abstract: A orifice fitting for measuring fluid flow in fluid pipelines has a seal mechanism to seal the orifice plate to the orifice fitting body. The orifice fitting has an orifice plate carrier which moves downward into a seat slot to position an orifice plate in the fluid flow. An annular seal mounts to the orifice plate assembly for engaging and sealing against the downstream side of the seat slot. A retaining ring mounts to an upstream side of the plate carrier. Threads on the retaining ring allow the ring to be adjusted to set the overall width of the plate carrier assembly to provide an interference fit in the seat slot. Set screws in the retaining ring bear against the orifice plate, which in turn bears against the seal member.