Positioning arrangement and method for positioning at least one object on a water bottom

Abstract

One aspect relates to a positioning arrangement ( 100 ) for positioning an object ( 50 ) under water ( 14 ) on a water bottom ( 15 ). The positioning arrangement ( 100 ) includes a barge ( 8 ) configured to float on the water ( 14 ); a carrier rig ( 1 ) positioned on the barge ( 8 ); a rope arrangement ( 7 ) by means of which the object ( 50 ) is suspended from a mast ( 28 ) of the carrier rig ( 1 ); and a positioning aid ( 60 ). The positioning aid ( 60 ) includes at least one of: (a) a constraining arrangement ( 4 ) arranged between the mast ( 28 ) and the object ( 50 ) and configured to restrict a lateral movement of the rope arrangement ( 7 ): and (b) a turntable arrangement ( 45 ) configured to adjust a rotational position of the object ( 50 ) about a vertical swiveling axis (a). A further aspect relates to a method for positioning an object ( 50 ) under water ( 14 ) on a water bottom ( 15 ). The method includes: providing a positioning arrangement ( 100 ) according to the first aspect; determining an actual position of the barge ( 8 ); determining an actual position of the object ( 50 ); controlling at least one of the constraining arrangement ( 4 ) and the turntable arrangement ( 45 ) to approach the object ( 50 ) to a desired position (P) above the water bottom based on at least one of the determined actual position of the barge ( 8 ) and the determined actual position of the object ( 50 ).

1 . A positioning arrangement for positioning an object under water on a water bottom, the positioning arrangement comprising:
 a barge configured to float on the water;   a carrier rig positioned on the barge;   a rope arrangement that suspends the object from a mast of the carrier rig; and   a positioning aid that includes at least one of: a constraining arrangement arranged between the mast and the object and configured to restrict a lateral movement of the rope arrangement or a turntable arrangement configured to adjust a rotational position of the object about a vertical swiveling axis.   
     
     
         2 . The positioning arrangement as claimed in  claim 1 , wherein a relative position between the barge and the constraining arrangement is adjustable in order to approach a desired position of the object on the water bottom. 
     
     
         3 . The positioning arrangement as claimed in  claim 1 , wherein a rotational position of the constraining arrangement is adjustable in order to approach a desired position of the object on the water bottom. 
     
     
         4 . The positioning arrangement as claimed in  claim 2 , further comprising:
 a control electronics that permanently regulates the relative position between the barge and the constraining arrangement and/or the rotational position of the object in order to approach the desired position of the object on the water bottom.   
     
     
         5 . The positioning arrangement as claimed in  claim 1 , wherein the positioning aid includes a localizer platform that carries the constraining arrangement and whose position relative to the barge is adjustable in order to approach the desired position of the object on the water bottom. 
     
     
         6 . The positioning arrangement as claimed in  claim 5 , wherein a relative position between the localizer platform and the constraining arrangement is adjustable by an adjustment mechanism in order to approach the desired position of the object on the water bottom. 
     
     
         7 . The positioning arrangement as claimed in  claim 5 , wherein the adjustment mechanism includes at least one hydraulic cylinder. 
     
     
         8 . The positioning arrangement as claimed in  claim 1 , wherein the rope arrangement includes a first rope and a second rope. 
     
     
         9 . The positioning arrangement as claimed in  claim 8 , wherein the constraining arrangement includes a first constraining device configured to constrict a lateral movement of the first rope and a second constraining device configured to constrict a lateral movement of the second rope. 
     
     
         10 . The positioning arrangement as claimed in  claim 8 , further comprising:
 a first winch and a second winch mounted on the carrier rig, wherein the first winch is configured to wind and/or unwind the first rope, the second winch is configured to wind and/or unwind the second rope, and the first winch and the second winch are configured to be operated in a synchronized manner and/or independently from one another.   
     
     
         11 . The positioning arrangement as claimed in  claim 10 , wherein the object includes a spreader bar; and the first winch and the second winch are configured to be controlled so that the spreader bar remains horizontal. 
     
     
         12 . The positioning arrangement as claimed in  claim 8 , further comprising:
 a swivel segment and a hinge that pivotably couples the swivel segment to the mast of the carrier rig;   a first deflection sheave mounted to the swivel segment and configured to deflect the first rope coming from the first winch downward; and   a second deflection sheave mounted to the swivel segment and configured to deflect the second rope coming from the second winch downward.   
     
     
         13 . The positioning arrangement as claimed in  claim 1 , further comprising:
 underwater distance measuring equipment configured to measure an actual position of the object above the water bottom underwater.   
     
     
         14 . The positioning arrangement as claimed in  claim 13 , wherein the underwater distance measuring equipment is mounted to a bottom of the barge. 
     
     
         15 . The positioning arrangement as claimed in  claim 13 , wherein the underwater distance measuring equipment includes at least one echo sounding device. 
     
     
         16 . The positioning arrangement as claimed in  claim 1 , wherein the object includes one or more depth vibrators. 
     
     
         17 . The positioning arrangement as claimed in  claim 16 , wherein the object includes a spreader bar and a number of depth vibrators attached to the spreader bar. 
     
     
         18 . The positioning arrangement as claimed in  claim 13 , wherein the spreader bar is mounted to the turntable arrangement. 
     
     
         19 . A method for positioning an object under water on a water bottom, comprising:
 providing a positioning arrangement having a barge configured to float on the water, a carrier rig positioned on the barge, a rope arrangement that suspends the object from a mast of the carrier rig, and a positioning aid that includes at least one of: a constraining arrangement arranged between the mast and the object and configured to restrict a lateral movement of the rope arrangement or a turntable arrangement configured to adjust a rotational position of the object about a vertical swiveling axis;   determining an actual position of the barge;   determining an actual position of the object;   controlling at least one of the constraining arrangement and the turntable arrangement to approach the object to a desired position above the water bottom based on at least one of the determined actual position of the barge and the determined actual position of the object).   
     
     
         20 . The method as claims in  claim 19 , wherein at least one of the following applies:
 the determined actual position of the barge includes a lateral position of the barge and/or a rotational position of the barge; and   the determined actual position of the object includes a lateral position of the object and/or a rotational position of the object.