An elongated pull element (14), in particular for an element of an expandable heavy equipment (1) comprises a bundle of load bearing fibers/fibres (41) extending along the length of the elongated pull element (14), and stiffening means (54) comprising an exoskeleton for increasing the bending stiffness of the elongated pull element (14), compared to the bending stiffness of the load bearing fibers/fibres (41).

Expandable heavy equipment 1, comprising a first frame element 5, a connector 11, at least one elongated pull element 14, and further frame elements 7. The pull element 14 is connected to the first frame element 5 with a first coupler 31 and to one 9 of the further frame elements 7 with a second coupler 35. The pull element 14 is in a folded state in a transport condition and in an extended state in a working condition. The pull element 14 comprises load bearing fibers/fibres 141 extending from the first coupler 31 to the second coupler 35. The pull element 14 comprises at least one flexible part 43 and at least two stiff parts 45. The flexible part 43 has a lower bending stiffness than the two stiff parts 45 and enables the pull element 14 to be arranged in the folded state.

Expandable heavy equipment 1, comprising a first frame element 5, a connector 11, at least one elongated pull element 14, and further frame elements 7. The pull element 14 is connected to the first frame element 5 with a first coupler 31 and to one 9 of the further frame elements 7 with a second coupler 35. The pull element 14 is in a folded state in a transport condition and in an extended state in a working condition. The pull element 14 comprises load bearing fibers/fibres 141 extending from the first coupler 31 to the second coupler 35. The pull element 14 comprises at least one flexible part 43 and at least two stiff parts 45. The flexible part 43 has a lower bending stiffness than the two stiff parts 45 and enables the pull element 14 to be arranged in the folded state.

A marine vessel and a method of operation of such a marine vessel include a crane with a boom including a main boom section and a jib section and a variable length stay mechanism. The lattice boom is movable from a hoisting position into a parking position by a routine including operating the variable length stay mechanism allowing the jib section to fold towards the main boom section. The crane is provided with a fixation device adapted to establish fixation of the jib section relative to the main boom section in a folded position. A boom rest is mounted on the hull. The routine further includes operating the luffing assembly to position the jib member of the folded jib section, fixated to the main boom section, in the parking position onto the boom rest.

A marine vessel and a method of operation of such a marine vessel include a crane with a boom including a main boom section and a jib section and a variable length stay mechanism. The lattice boom is movable from a hoisting position into a parking position by a routine including operating the variable length stay mechanism allowing the jib section to fold towards the main boom section. The crane is provided with a fixation device adapted to establish fixation of the jib section relative to the main boom section in a folded position. A boom rest is mounted on the hull. The routine further includes operating the luffing assembly to position the jib member of the folded jib section, fixated to the main boom section, in the parking position onto the boom rest.

A hydraulic rotary drive includes a first rotary drive element and at least two annular pistons connected to the first rotary drive element in a rotationally fixed manner and configured to be axially movable on the first rotary drive element between two end positions. Each annular piston has two annular spur serrations directed away from one another. The hydraulic rotary drive includes a second rotary drive element with ring type serrations that are complementary to the spur serrations of the annular pistons. The hydraulic rotary drive includes a control unit that is configured to control supply of hydraulic fluid to the annular pistons to cause a reciprocating movement of the annular pistons on a shaft in accordance with an operating signal. The hydraulic rotary drive includes a sensor arrangement communicatively coupled to the control unit and arranged to detect the positions of the annular pistons along respective sliding paths.

A hydraulic rotary drive includes a first rotary drive element and at least two annular pistons connected to the first rotary drive element in a rotationally fixed manner and configured to be axially movable on the first rotary drive element between two end positions. Each annular piston has two annular spur serrations directed away from one another. The hydraulic rotary drive includes a second rotary drive element with ring type serrations that are complementary to the spur serrations of the annular pistons. The hydraulic rotary drive includes a control unit that is configured to control supply of hydraulic fluid to the annular pistons to cause a reciprocating movement of the annular pistons on a shaft in accordance with an operating signal. The hydraulic rotary drive includes a sensor arrangement communicatively coupled to the control unit and arranged to detect the positions of the annular pistons along respective sliding paths.

A telescoping extendable boom and a foldable telescoping extendable boom for transporting an item, are disclosed. The foldable telescoping extendable boom having tubular elements (12) and (14) and (15, 17, 18, 19) and (20) each arranged with a longitudinally extending track (25, 29) inside the tubular element. Each longitudinally extending track (25, 29) supports a single shuttle (26) and (30) respectively, internally inside its tubular element (17) and (15), respectively, for movement therealong. Each shuttle (26) and (30) is equipped with a clamp (27) and (30) to selectively clamp the item (298). The longitudinally extending tracks (25, 29) of immediately connecting telescoping tubular elements (17) and (15) are located opposite each other. The inner tubular elements inside said telescoping extendable boom are arranged at their near ends to allow their shuttles to access shuttles of outer tubular elements to enable the clamps (27) and (31) thereof to transfer a said item (298) therebetween.

A telescoping extendable boom and a foldable telescoping extendable boom for transporting an item, are disclosed. The foldable telescoping extendable boom having tubular elements (12) and (14) and (15, 17, 18, 19) and (20) each arranged with a longitudinally extending track (25, 29) inside the tubular element. Each longitudinally extending track (25, 29) supports a single shuttle (26) and (30) respectively, internally inside its tubular element (17) and (15), respectively, for movement therealong. Each shuttle (26) and (30) is equipped with a clamp (27) and (30) to selectively clamp the item (298). The longitudinally extending tracks (25, 29) of immediately connecting telescoping tubular elements (17) and (15) are located opposite each other. The inner tubular elements inside said telescoping extendable boom are arranged at their near ends to allow their shuttles to access shuttles of outer tubular elements to enable the clamps (27) and (31) thereof to transfer a said item (298) therebetween.

A self-erecting crane includes a mast supporting a foldable jib having jib elements articulated together, configurable between a transport configuration and a work configuration. The crane also includes a motor-driven folding/unfolding system for performing configuration change operations implementing kinematics of folding and unfolding the jib, and a control/command system connected to the motor-driven folding/unfolding system to drive it. One or several inclinometer(s) are mounted on one or several jib element(s) to measure actual inclinations of the jib element(s) with respect to a reference axis. The control/command system is configured to drive the motor-driven folding/unfolding system according to the actual inclinations of the jib element(s) during the kinematics of folding and unfolding the jib.