Patent ID: 7461831

Claim:
A workover rig comprising a derrick mounted on a support adjacent to a well; a first set of sheaves movably provided on said support; a second set of sheaves fixed with respect to said support and facing said first set of sheaves; a drive mechanism provided on said support, said drive mechanism connected to said first set of sheaves for moving said first set of sheaves with respect to said second set of sheaves; an assembly of crown sheaves provided on said derrick; an operating cable having both ends fixed, said operating cable extending around said first set of sheaves, said second set of sheaves and said assembly of crown sheaves; a traveling block positioned beneath said assembly of crown sheaves above the well; and traveling block sheaves rotatably provided on said traveling block for receiving said operating cable, wherein adjustment of said first set of sheaves with respect to said second set of sheaves responsive to operation of said drive mechanism selectively lengthens and shortens said operating cable between said first set of sheaves and said second set of sheaves and causes said traveling block to rise and fall above the well.