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DESIGN
 The ram assemblies are equipped with cast steel interface heads which incorporate a plural tooth profile. The head assemblies are mounted on forged steel spherical supports which are designed to allow automatic alignment during engagement yet retain the greatest load bearing capacity in a minimum space. Horizontal rotation, caused by tug pitch, is transmitted to the ram by guide pins on the top and bottom of the interface head. Rotation is carried by a bronze bushing which is installed in the cylindrical ram housing. All other relative motions are restricted.
The extension and retraction of the ram assembly is accomplished by an alloy threaded shaft turning in a bronze threaded boss incorporated into the inboard end of the ram assembly. The screw is actuated by high speed and low speed electric motors driving through gear reduction mounted on the interior end of the housing assembly. In low speed mode, extension force exceeds 260,000 lbs. on each ram. Hydraulic drive motors are optionally available.
The transverse thrust from the actuator screw assembly is carried by a roller type thrust bearing rated in excess of the worst condition athwartship loads revealed in model tank tests. A load cell is incorporated into the bearing housing to monitor thrust forces.
MODEL TESTS
The Intercon System has been designed to meet severe operating conditions. These criteria and operating load parameters were tested by computer simulation, and dynamic tank testing at the Netherlands Ship Model Basin. These initial tank tests utilized models of a 260,000 barrel capacity barge pushed by a 6000 HP class tug equipped with lateral connecting rams simulating the Intercon design. Load tests were conducted in 22 ft. mean seas, and included various wave heights in the spectrum. Substantial data was generated by wave heights, periods, and directions; these results guided the final engineering phase of the Intercon System. Additional model testing is conducted to verify coupler sizing on new applications.
Upon review of the design and NSMB test data, the U.S. Coast Guard approved the System for Dual Mode tug-barge service as defined by USCG NAVIC 2-81.
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