Abstract: A thin film evaporator has a shell with tubes extending through the shell in at least one pass. The shell has a top and a bottom. Process fluid flows through the tubes. A suction from a compressor is applied to the top of the shell at a refrigerant outlet. Refrigerant is introduced into the shell at the bottom and is distributed across the bottom region of the shell. The refrigerant flows up and contacts the tubes, exchanging heat therewith before flowing out of the shell top. Oil in the refrigerant contacts the shell wall and drains into a sump.

Abstract: Automatic oil removal from an ammonia evaporator/low pressure vessel in a refrigeration system is disclosed. A liquid refrigerant level controller is utilized to drain the oil. The controller works under the principle of fluid thermal conductivity. Oil having lower thermal conductivity as compared to liquid ammonia, activates the probe which in turn opens the valve to drain the oil accumulated in a trap of an evaporator or a low pressure vessel.

Abstract: An evaporator for a refrigeration system is disclosed which includes a tube bundle with various kinds of tubes. Depending upon the size of a tube bundle, at least two different kinds of tubes are used along the height of the tube bundle. Highly efficient nucleate boiling characteristics tubes are used in the lower section and prime surface or only inside surface enhanced tubes are used in the top section to minimize the adverse effects of vapor blanketing. Tubes in the mid sections could be the same or different than the tubes in the lower and upper sections.

Abstract: The end bonnets for a dry expansion heat exchanger of the shell and tube type having a plurality of bundles of tubes. A pair of end bonnets on opposite ends of the shell. Vertical flat impingement plates between the horizontal baffle ribs within the bonnets subdivide the bonnets into subchambers corresponding to the tube count in respective tube bundles. The cross-sectional areas of successive bundles of tubes increase to allow for expansion of the coolant as it flows through the heat exchanger and absorbs heat from the fluid to be cooled. The vertical plates in the end bonnets define restricted flow areas for the coolant which increases in flow area corresponding to the respective tube bundles.

Abstract: An evaporator for a refrigeration system is disclosed which includes a tube bundle with various kinds of tubes. Depending upon the size of a tube bundle, at least two different kinds of tubes are used along the height of the tube bundle. Highly efficient nucleate boiling characteristics tubes are used in the lower section and prime surface or only inside surface enhanced tubes are used in the top section to minimize the adverse effects of vapor blanketing. Tubes in the mid sections could be the same or different than the tubes in the lower and upper sections.