Abstract: An apparatus for gauging the height and outer diameter of a collar in a heat exchanger plate fin. The apparatus comprises a vertically displaceable carriage overhanging a base on which a plate fin can be mounted for measurement. On the carriage are mounted two displacement indicators, in the preferred embodiment electrical linear gauges. One indicator is oriented so that its indicator probe measures vertical displacement and, through the configuration of the apparatus, produces an output that can be translated to a measure of the height of the fin collar. The other indicator is oriented so that its indicator probe measures horizontal displacement. The independent but concerted positioning of two measuring blades to contact diametrically opposite points on the fin collar is resolved into an output from the horizontal indicator that can be translated into a measure of the outer diameter of the fin collar. In a preferred embodiment, the outputs of the two indicators are read on electrical digital readouts.

Abstract: A single-station tube expander apparatus bells and expands the open ends of heat exchanger hairpin tubes in a plate-fin heat exchanger unit. A frame supports belling jaw fingers which close over and the open ends of the tubes so that a belling device can enter the tube ends to urge the tube outward into a profile surface formed in the mating faces of the fingers. Also on the frame are mounted expander jaw fingers which close over tube ends which have been belled previously, and hold the associated hairpin tubes against axial movement while expander rods pass into the associated tube legs to urge the hairpin tube legs outward to contact against the fin plates and tube sheets of the fin pack heat exchanger. The belling fingers and belling device move step by step from one tube to another, and the expander gripping fingers and expander rods follow the belling fingers and belling device.

Abstract: A flexibly programmable belling and tension expanding device for plate fin heat exchanger coils is carried on a shuttle or carriage that moves between first and second work stations. An operator assembles a fin plate heat exchanger unit at a work table at one work station while the device automatically bells and expands the hairpin tubes of another unit at a second station. When assembly is complete, the operator signals a programmable controller, and the shuttle brings the device to the one coil after it completes the expanding of the other, and it commences an automatic expanding operation. Then the operator removes the expanded coil and assembles another coil at the second station while the device is belling and coiling at the one station.