bolted around the hinge. The two hoist drum wire ropeson the crane are rigged as the holding and closing linesfor controlling of the bucket. An example of a clamshellrigging configuration is shown in figure 12-30.The tag line winder (fig. 12-31) controls the tensionon the tag line that helps prevent the clamshell fromtwisting during operations. Like the clamshell bucket,the tag line winder will exchange with most makes ormodels of cranes in the same-size range.DRAGLINEThe dragline component (fig. 12-32) consists of adragline bucket and fairlead assembly. The wire ropecomponents of the dragline are the drag cable, the buckethoist, and the dump. Once a crane is rigged with adragline, the crane is referred to by the name of theattachment,When you are loading the bucket, the fairlead (fig.12-33) guides the drag cable onto the hoist drum. Thehoist wire rope, which is reeved through the boom pointsheaves, raises and lowers the bucket.WARNINGOn some model of cranes, you must makesure the fairlead is in a vertical position whenlowering the boom to avoid bending the cordsof the boom base.Figure 12-31.—Tag line winder.When changing attachments from hook block orclamshell to dragline, check the operator’s manual forthe lengths and diameter size of wire rope required fordragline operations. The pulling force of the draglineFigure 12-30.-Clamshell rigging configuration.12-18
Integrated Publishing, Inc. - A (SDVOSB) Service Disabled Veteran Owned Small Business