DEVELOPMENT AND TESTING OF THE GLENN EDWARDS DREDGE PUMPS

摘要

Manson Construction Co. performs marine construction and dredging throughout the coastal United States and overseas. In January of 2006, Manson launched the largest trailing suction hopper dredge in the United States, the Glenn Edwards, having a 9,175 m~3 (12,000 yard~3) capacity. This dredge is fitted with two newly designed LHD-38x38-58(60.4) C/4HE GIW dredge pumps having 1.53 m (60.4 inch) diameter impellers with 1 m (39.37 inch) suctions, each being driven by a 1721 kW (2308 hp) diesel engine. These pumps were developed specially for this dredge and tested within the GIW Hydraulic Test Lab up to flows exceeding 6800 l/s (107,794 gal/min) corresponding to 307 rpm operation.The writers in this paper describe the design considerations, CFD modeling and development of the hydraulics for this new pump, some of the mechanical details of its construction and how its performance was validated under full-scale test conditions.Illustrative examples of pump operation for both sand-type dredging and water filling applications have been provided. In the case of the sand dredging scenario, no significant dredge limitation i.e. engine speed limit, engine power limit, pump/system suction limit (NPSH) would be reached. In the water filling illustration, the new design pump achieved ～21% greater flow-rate resulting in a 21% reduction in hopper fill time. At the maximum flow-rate, the pump consumed the full engine capacity and has reached its suction limit (NPSHR) based on the system NPSH availability indicating the design did meet the desired goals for the field application.