초록 ▼

A jack usable for leveling a marine platform jacket by lifting a tubular leg or pile guide relative to a pile extending upwardly therethrough includes a gripping unit having slips which engage and grip the pile and which in a predetermined elevated condition of the tubular member are engaged by that

A jack usable for leveling a marine platform jacket by lifting a tubular leg or pile guide relative to a pile extending upwardly therethrough includes a gripping unit having slips which engage and grip the pile and which in a predetermined elevated condition of the tubular member are engaged by that member and urged axially thereby in a grip tightening direction acting to positively lock the gripping unit against movement either upwardly or downwardly relative to the pile.

대표청구항 ▼

The combination comprising first and second members, and jacking mechanism for moving said members along an axis relative to one another, said jacking mechanism comprising: two structures which are relatively axially movable and transmit force in opposite directions to said two members respectively;

The combination comprising first and second members, and jacking mechanism for moving said members along an axis relative to one another, said jacking mechanism comprising: two structures which are relatively axially movable and transmit force in opposite directions to said two members respectively; and power operated means for moving said two structures axially relative to one another and thereby jacking said two members axially relative to one another; one of said structures including a slip bowl adapted to be urged axially by said power actuated means, and at least one slip engaging said bowl in a relation to be cammed thereby against said first member in gripping relation; said second member having a portion extending to a location at which it can apply axial force to said slip in a grip tightening direction upon relative axial actuation of said members by said power operated means.