Marine loading arm

Abstract

 A marine loading arm (1) comprises a plurality of component arm parts including a support column (12) and one or more mutually movable arm elements (10, 38) driven by a driving system controlled by electric motors (24, 32, 48) and respective mechanical transmission or drive units (26, 34, 50).

Description

BACKGROUND OF THE INVENTION

[0001] The present invention relates to a marine loading arm.

[0002] As it is known, a marine loading arm is an apparatus comprising a plurality of structural elements articulatedly coupled to one another, for connecting a ship to a pipeline on a harbor pier.

[0003] Such an apparatus allows fluids with different pressures, temperatures and viscosities to be conveyed therethrough.

[0004] Marine loading arms are constructed depending on the conveyed liquid or gas type, pressure, temperature and flow-rate, and on environmental constraints, such as tide, wind and possible earthquake events.

[0005] Prior marine loading arms are conventionally either manually or hydraulically operated and comprise a plurality of articulations or articulated joints, to follow, within set limits, the movement of the moored ship.

[0006] Prior marine loading arms comprise a connection and disconnection device, including dedicated seals and gaskets, for safely coupling the arm to a ship manifold assembly.

[0007] Such a marine arm is selected based on factors such as the harbor characteristics, ship size, loading flow rate, pressure and temperature, environmental constraints, such as tide line and wind conditions and a resistance to possible earthquake.

[0008] The marine arm can also comprise additional components such as quick connections, either of a hydraulic or a manual type, position control devices and emergency unlocking or releasing systems.

[0009] The same Applicant has been making marine loading arms for several years, in a continuous attempt to improve their operating features and to meet all enforcing anti-polluting and safety requirements.

[0010] In all prior marine loading arms, the arm parts are operatively driven, to connect the arm to the ship manifold, by a driving system consisting of hydraulic pistons and a control central unit.

[0011] Said prior driving system involves a comparatively high maintenance requirement, because of the large weight, size and complex construction of said hydraulic control central unit, in addition to a limited operating area and a non perfectly even movement of the arm parts.

SUMMARY OF THE INVENTION

[0012] Accordingly, the aim of the present invention is to provide such a novel marine loading arm overcoming the above mentioned drawbacks of prior marine arms.

[0013] Within the scope of the above mentioned aim, a main object of the present invention is to provide such a marine loading arm all the parts of which are so driven as to simplify the overall apparatus.

[0014] Another object of the invention is to provide such a marine loading arm which may be managed or controlled with an improved managing or controlling speed.

[0015] A further object of the present invention is to provide such a marine loading arm having improved operating safety features.

[0016] A further object of the present invention is to provide such a marine loading arm which may be easily serviced and maintained.

[0017] A further object of the present invention is to provide such a marine loading arm without polluting oil leakages.

[0018] A further object of the present invention is to provide such a marine loading arm device which, owing to its specifically designed structural features is very reliable and safe in operation.

[0019] According to one aspect of the present invention, the above mentioned aim and objects, as well as further objects, which will become more apparent hereinafter, are achieved by a marine loading arm, characterized in that said marine loading arm comprises a plurality of component arm parts including a support column and one or more mutually movable arm elements driven by a driving system controlled by electric motors and respective mechanical transmission or drive units.

BRIEF DESCRIPTION OF THE DRAWINGS

[0020] Further characteristics and advantages of the present invention will become more apparent hereinafter from the following detailed disclosure of a preferred, though not exclusive, embodiment of the invention which is illustrated, by way of an indicative but not limitative example, in the accompanying drawings, where:

Figure 1 is a side elevation view showing the marine loading arm, according to the present invention, installed on a pier, therefrom/thereto a fluid must by transferred to/from a ship;

Figure 2 is a front elevation view of the marine loading arm support column;

Figure 3 is a rear elevation view;

Figure 4 is yet another schematic view showing the subject marine loading arm installed on a pier;

Figure 5 is a perspective view schematically showing the arrangement of a first electric motor and a related transmission gear;
and

Figure 6 is a perspective view schematically showing an arrangement of further electric motor-transmission assemblies.

DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0021] With reference to the number references of the above mentioned figures, the marine loading arm according to the present invention, which has been generally indicated by the reference number 1, is installed on a pier 100 therefrom/thereto a fluid must be transferred or conveyed to/from a ship 110.

[0022] As shown, said marine loading arm 1 comprises a support column 12, anchored to the pier 100, and supporting a fluid duct 20, at a bottom of which a flange 16 for connecting to a harbour system is arranged.

[0023] A rotary joint 22 is arranged at a top end portion of the duct 20 to allow the inner arm 10 to turn about a vertical axis of said column 12.

[0024] This rotary or turning movement is driven or controlled by an electric motor 24 coupled to a transmission assembly 26.

[0025] More specifically, the movement transmission to the marine loading arm portions may be performed by different driving systems which may comprise a gear wheel, a coupling assembly, or an worm screw system in replacement of hydraulic pistons, said system being analogous to that usually applied to an electrically operated gate.

[0026] In the embodiment shown here, a gear wheel system, representing one of several constructional possibilities of the arm structure, is used.

[0027] Above said joint 22, said duct comprises a right angle bent portion 28, at an end portion of which another joint 30, similar to said joint 22, is arranged.

[0028] Said joint 30 allows the inner arm 10 to turn with respect to the bent portion 28 about a horizontal axis, perpendicular to the plane formed by the column 12 and arm 10.

[0029] The above rotary or turning movement is driven or controlled by a second electric motor 32, coupled to a transmission or drive 34, as shown in figure 3.

[0030] Thus, the inner arm 10 and related inner duct 36 are adapted to freely turn or swing in a vertical plane, through the joint 30, and further turn and swing in a horizontal plane, through the joint 22.

[0031] As shown, the duct 36 is coupled to an outer duct 38, forming the outer arm, by a third rotary joint 40 and being driven by a driving rod coupled to a parallelogram assembly 42.

[0032] Said parallelogram assembly 42 is adapted to turn in its laying plane about pivot pins 44 and 46, as driven by a third electric motor 48, shown in figure 2, coupled to a transmission or drive 50, shown in figure 3.

[0033] Thus, with the rotary movement of the parallelogram assembly, the outer duct 38 will be adapted to freely turn with respect to the inner duct 36, according to a horizontal axis, with a fulcrum pivot at the rotary joint 40.

[0034] The outer duct 14, in turn, supports, at a bottom end portion thereof, a device formed by assembling three joints with a quickly detached valve and a coupling assembly 18, allowing a quick connection/disconnection of the manifold of the ship 110.

[0035] Thus, the coupling assembly 18 will have three further freedom degrees.

[0036] It has been found that the invention fully achieves the intended aim and objects.

[0037] In fact, the invention has provided a marine loading arm comprising a plurality of arm portions which may be mutually operated or displaced to allow a movement according to three freedom degrees of an end connecting element.

[0038] Differently from prior driving systems, in which the above mentioned arm portions are controlled or driven by a hydraulic driving system including a hydraulic control central unit, the marine loading arm according to the present invention has a much more simple construction and is driven by an electric motor system which, through an electronically controlled transmission or drive device, drives all the arm parts without the need of providing any hydraulic central control unit.

[0039] In particular, the electric motors may so drive the arm parts thereby allowing the arm coupling system to be easily anchored to the ship manifold mouth portion.

[0040] In such an operation, the inventive electric motor system precisely fits the ship swinging movement, in an active managing mode of operation which, in an emergency condition, allows to immediately intervene, even with the loading arm in a connected condition thereof, to greatly release stress and strains on the arm construction and ship manifold mouth portion.

[0041] Moreover, the rotary electric motor drive according to the present invention provides an operating apparatus which may drive the arm parts in a very flexible, broad and even manner, through 360° on a horizontal plane.

[0042] Furthermore, the reaction times of the inventive apparatus are much shorter than those of a prior apparatus controlled by a hydraulic system.

[0043] Moreover, the subject apparatus has the further main advantage that it allows to operate with a very high precision, through electric step motors and sensors, by determining the arm and arm part positions, which is very useful for a safe operation and in emergency conditions.

[0044] Another very important advantage of the marine loading arm according to the present invention is that it is operated without oil leakages.

[0045] Moreover, the inventive apparatus has the further main feature that, for operation, the sole power source which is always available on the pier may be used.

[0046] As a further main feature of the inventive marine loading arm, it may be serviced and maintained at a low cost since it has a size, weight and structural complexity much smaller than prior hydraulic system driven marine arm apparatus.

[0047] It should be apparent that the used materials, as well as the contingent size and shapes, may be any, depending on requirements.

Claims

1. A marine loading arm, characterized in that said arm comprises a plurality of component arm parts including a support column and one or more mutually movable arm elements driven by a driving system controlled by electric motors and respective mechanical transmission or drive units.

2. A marine loading arm, according to claim 1, characterized in that said transmission or drive units comprise gear wheels.

3. A marine loading arm, according to claim 1, characterized in that each said transmission or drive unit is coupled by a direct type of coupling.

4. A marine loading arm, according to claim 1, characterized in that each said transmission or drive unit comprises a worm screw.

5. A marine loading arm, according to claim 1, characterized in that said marine loading arm comprises a support column connected to a pier and supporting a fluid duct having a flange arranged at a bottom thereof for coupling to a harbor system, a rotary joint being arranged at a top end portion of the duct for allowing the inner arm to rotate about a vertical axis of said column, said inner arm being rotatively driven by a first electric motor coupled to a said transmission or drive unit.

6. A marine loading arm, according to claim 5, characterized in that said fluid duct comprises, on a top of said joint, a right angle bent portion at an end portion of which a second joint is arranged, said second joint allowing the inner arm to rotate with respect to said right angle bent portion about a horizontal axis perpendicular to a plane formed by said column and inner arm, said rotary movement being controlled by a second electric motor coupled to a said transmission or drive unit, said inner arm and related inner duct being free of turning or swinging in a vertical plane through said first joint and further turning and swinging in a horizontal plane, through said second joint.

7. A marine loading arm, according to claim 6, characterized in that said fluid duct is coupled to a further outer duct constituting the outer arm, through a third rotary joint and being driven by a driving rod coupled to a parallelogram assembly adapted to rotate about respective pivot pins and being driven by a third electric motor coupled to a said transmission or drive unit, thereby, as said parallelogram assembly is rotatively driven, said outer duct may rotate about the inner duct according to a horizontal axis with a fulcrum at the rotary joint.

8. A marine loading arm, according to claim 7, characterized in that said outer duct has a bottom end portion supporting a device formed by coupling three joints with a quickly detached valve and a coupling assembly allowing a quick connection/disconnection of a ship manifold, said coupling assembly having three further freedom degrees.

Drawing