Split block for extended travel

A crane block defining a central main fall symmetry line for vertical rope travel during movement of a rope hoist comprising:

• a crown block for mounting to a crane boom and having a first row of relatively large diameter sheaves in tandem with a second row of relatively small diameter sheaves;
• a movable block having a third row of relatively small diameter sheaves reeved with said second row;
• a traveling block having a fourth row of relatively large diameter sheaves reeved with said first row;
• one of said second or third rows having said sheaves canted with respect to said main fall symmetry line for vertical travel of said rope between said second and third rows of said sheaves;
• connecting means for removably securing said movable block with said traveling block for lifting relatively heavy loads over relatively small vertical travel;
• connecting means for removably securing said movable block in a two-blocked configuration beneath said crown block for lifting relatively lighter loads over relatively extended vertical travel;
• detachable support means on said traveling block for defining a set of outboard sheaves on either side of said main fall symmetry line and a set of inboard sheaves across said main fall symmetry line;
• means for detaching said outboard sheaves from said inboard sheaves for further extending vertical travel of said traveling block and reducing the size of said traveling block when said movable block is attached to said crown block;
• and
• means for removably attaching said detachable support means for said outboard sheaves to said movable block to reduce rope and sheave wear and to reduce down-haul weight when extended vertical travel is required for relatively light loads.