Cargo hatch

Abstract

This invention relates to a cargo hatch for use on bulk carriers or other vessels and to allow access to a cargo hold. The cargo hatch includes one or more hatch covers disposed on a hatch coaming surrounding a hatch opening through which access to the cargo hold is permitted. To prevent water from entering the cargo hold from the external environment, a seal is typically provided between the hatch cover and the hatch coaming. These seals can be prone to degradation. This invention proposes a cargo hatch for a bulk carrier comprising a hatch coaming surrounding a hatch opening and a hatch cover configured to be removably positioned on the hatch coaming such that the hatch cover reversibly closes the hatch opening, wherein the cargo hatch includes two sealing systems configured to provide respective and separate seals between the hatch coaming and the hatch cover during use.

Description

Technical Field

[0001] This invention relates to cargo hatches, and more specifically and non-exclusively to cargo hatches for bulk carriers. Background Technology

[0002] Bulk carriers are commercial vessels that transport bulk cargoes such as coal, cement, ore, and grain. Typically, bulk cargo is directly stacked in one or more cargo holds of a bulk carrier without packaging or any additional containers, although bulk carriers can also be used to transport other cargoes (e.g., packaged cargo). On a bulk carrier, access to the cargo holds is via hatch openings on the ship's deck, which are covered by one or more hatch covers. Hatch covers are set on hatch coamings (vertically extending flat surfaces / plates) that completely surround the hatch openings and provide a seal to protect the cargo holds from weather and seawater.

[0003] Traditionally, a seal is achieved using a compression bar mounted on top of the hatch coaming and a mating gasket (e.g., a rubber gasket) installed in a channel (e.g., a steel channel) at the bottom of the hatch cover. When the hatch cover is in its closed position, the gasket rests on the compression bar, causing it to conform to the shape of the compression bar under the weight of the hatch cover, thus forming a seal. This type of prior art arrangement is known to provide protection against rainwater, but offers only limited protection against seawater entering the cargo hold (e.g., during severe weather at sea).

[0004] Furthermore, the effectiveness of this traditional type of sealing can deteriorate over the service life of a bulk carrier due to damage to components of the cargo hatches, such as hatch coamings, hatch covers, gaskets, or compression bars. This damage can be caused by weathering or corrosion over time, or even by accidents during loading and unloading. Therefore, one of the most common problems in transporting bulk cargoes and other goods on bulk carriers is contamination caused by seawater or rainwater entering one or more cargo holds. This can lead to cargo damage (especially since cargo is often unpackaged) and subsequent insurance claims.

[0005] The present invention was designed based on the above considerations. Summary of the Invention

[0006] In general, the present invention relates to a cargo hatch for a bulk carrier, the cargo hatch including a hatch coaming surrounding a hatch opening and a hatch cover configured to be removably positioned on the hatch coaming such that the hatch cover reversibly closes at least a portion of the hatch opening, wherein the cargo hatch includes two sealing systems (e.g., a double-seal arrangement) configured to provide respective and separate seals between the hatch coaming and the hatch cover in use.

[0007] In a first aspect, a cargo hatch for a bulk carrier is provided, comprising: a hatch coaming surrounding a hatch opening; a hatch cover configured to be removably positioned on the hatch coaming such that the hatch cover reversibly closes at least a portion of the hatch opening; a first sealing system including a gasket and a compression rod, and configured to provide a seal between the hatch coaming and the hatch cover in use; and a second sealing system including an expandable seal, and configured to provide a seal between the hatch coaming and the hatch cover in use.

[0008] As used in this article, "in use" means that the hatch cover is on the hatch coaming, so that the hatch opening is closed by the hatch cover. In this case, the cargo hatch can be said to be in the closed state.

[0009] By providing a cargo hatch according to the first aspect, an improved seal can be achieved between the hatch cover and the hatch opening (e.g., defined by the hatch coaming). In particular, water ingress into the cargo hold and contamination of the cargo within the hold can be reduced or eliminated. Specifically, a second sealing system including an expandable seal can help enhance the watertightness of the cargo hatch and the cargo hold. Furthermore, by providing a second sealing system including an expandable seal, the cargo hatch can remain watertight during repeated use, even though the hatch cover and / or hatch coaming (e.g., their dimensions) undergo physical changes over time, for example, due to weathering and / or corrosion.

[0010] The hatch cover can be configured to be removably positioned on the hatch coaming so that the hatch cover reversibly closes the hatch opening (e.g., the entire hatch opening). In other words, a single integral hatch cover can be used to close the hatch opening.

[0011] By providing a hatch cover that reversibly closes the entire hatch opening, fewer paths are provided to prevent potential water ingress into the hatch compared to conventional side-roll hatch covers that typically include two cooperating hatch covers, each covering a corresponding half of the hatch opening and meeting at the mid-section seam when closed. In this conventional type of side-roll hatch cover design, the mid-section seam provides an additional path for water to enter the hatch, in addition to the area around the edge of the hatch opening, where one or more hatch covers abut against the hatch coaming. In other words, in embodiments where the hatch cover reversibly closes the entire hatch opening, the length of one or more sealing systems required for the cargo hatch is reduced.

[0012] The operation of the cargo hatch according to the first aspect is as follows. After cargo is loaded into the cargo hold through the hatch opening, the hatch cover moves into place so that it rests on the hatch coaming. As a result, the hatch opening is closed by the hatch cover. This process can be referred to as closing the hatch cover. A gasket and a compression rod can be positioned on the opposing surfaces of the hatch cover and the hatch coaming. For example, the compression rod can be located on the hatch coaming, and the gasket can be located on the hatch cover. When the hatch cover is on the hatch coaming, the gasket abuts (e.g., is located on) the compression rod, and the gasket is shaped to fit the compression rod (e.g., under the weight of the hatch cover), thereby providing a seal between the hatch coaming and the hatch cover. This is the first sealing system.

[0013] When the hatch cover is closed, the expandable seal is in an unexpanded state. When the hatch cover is on the hatch coaming, the expandable seal expands into an expanded state. In the expanded state, the expandable seal abuts against both the hatch cover and the hatch coaming, and is shaped to fit the hatch cover (e.g., the hatch cover skirt, see below) and the hatch coaming such that the seal is positioned between the hatch cover and the hatch coaming. This is the second sealing system. In the expanded state, the volume of the expandable seal is larger than that of the expandable seal in the unexpanded state.

[0014] When access to the cargo hold is required, the hatch cover can be removed from the hatch opening, allowing entry into the cargo hold through the hatch opening. When the hatch cover is removed from the hatch opening, the cargo hatch can be considered to be in an uncovered state. In the uncovered state, the hatch cover can be adjacent to the hatch opening, allowing entry into the cargo hold through the hatch opening.

[0015] The expandable seal can be a reversible expandable seal. In other words, the expandable seal can expand from an unexpanded state to an expanded state, and also (e.g., subsequently) collapse (i.e., reduce in volume) from the expanded state back to the unexpanded state. In embodiments where the expandable seal is a reversible expandable seal, the operation of the expandable seal can be as follows: When the cargo hatch is closed, the expandable seal can expand from an unexpanded state to an expanded state to provide a seal between the hatch cover and the hatch coaming, as described above. When the hatch cover is to be removed, the expandable seal can collapse from the expanded state to the unexpanded state, such that a second seal is no longer provided between the hatch cover and the hatch coaming. This makes it easier to remove the hatch cover from the hatch opening to open the hatch. This also means that the expandable seal returns to the unexpanded state, for example, after new cargo has been loaded into the hatch via the hatch opening, preparing for the next closure of the hatch cover.

[0016] An expandable seal can be an inflatable seal. For example, the seal can be expanded from a non-expanded state to an expanded state by directing inflation gas (e.g., air) into an inflatable volume defined within the inflatable seal. Furthermore, the seal can collapse from an expanded state to an unexpanded state by venting or removing inflation gas from the inflatable volume. For example, an expandable seal may include a bladder surrounding a cavity. The volume of the cavity can be increased (e.g., from a non-expanded state to an expanded state) by injecting gas, and in embodiments with a reversible expandable seal, the volume of the cavity can be reduced (e.g., from an expanded state to an unexpanded state) by removing gas.

[0017] Hatch covers may include a bottom surface that faces the hatch opening during use, such as the cargo hold of a bulk carrier. Hatch covers may also include a top surface on the opposite side of the bottom surface from the hatch opening during use. In use, the top surface may form part of the bulk carrier's deck.

[0018] Hatch openings can have a main axis. Hatch covers can also have a corresponding main axis. The main axes of the hatch opening and hatch cover can extend vertically; for example, the main axis can be parallel to the vertical axis of the bulk carrier. When the cargo hatch is closed, the main axis of the hatch cover can be collinear with the main axis of the hatch opening.

[0019] The hatch opening can have a width of approximately 10m to 25m, for example, approximately 15m to 20m, or approximately 15m (e.g., in a direction roughly between the port and starboard sides of the bulk carrier). The length of the hatch opening can be approximately perpendicular to the width and therefore parallel to the centerline of the bulk carrier. The length of the hatch opening can be less than the width. For example, the length of the hatch opening can be between approximately 5m and approximately 20m, for example, between approximately 10m and approximately 15m, or approximately 10m.

[0020] The hatch coaming may include a compression rod of the first sealing system. For example, the hatch coaming may have a top surface to which the compression rod is attached (e.g., the deck facing away from the bulk carrier, for example, facing a generally vertical direction). The hatch cover may include a corresponding gasket that abuts against (e.g., is located on) the compression rod in use and is shaped to fit the compression rod, thereby providing a seal between the hatch coaming and the hatch cover. The seal can be maintained by the downward force of the hatch cover on the compression rod.

[0021] The first sealing system can extend between all connection areas between the hatch cover and the hatch coaming. For example, the compression rod can extend completely around the perimeter of the hatch coaming. For example, the compression rod can extend completely around the top of the hatch coaming. In such an embodiment, the gasket of the first sealing system can extend completely around the area of ​​the hatch cover (when the cargo hatch is closed) corresponding to the area where the hatch cover connects to the compression rod (e.g., via the gasket). For example, the gasket of the first sealing system can extend completely around the perimeter of the hatch cover (e.g., on the bottom surface of the hatch cover) and can be spaced inwardly from the outer edge of the hatch cover such that the shape of the gasket (when viewed from below) corresponds to the shape of the compression rod on the hatch coaming (when viewed from above).

[0022] In some embodiments, the hatch opening may have a quadrilateral (e.g., rectangular) shape. In other words, the hatch opening may be a quadrilateral hole (e.g., an opening) in the deck of a bulk carrier. Therefore, when viewed from above, the hatch coaming extending around the entire perimeter of the hatch opening may have a quadrilateral shape. Furthermore, when viewed from above, the compression bar (e.g., on the top surface of the hatch coaming) may also have a quadrilateral shape such that it surrounds the perimeter of the hatch opening.

[0023] In embodiments where the compression rod has a quadrilateral shape, the corresponding gasket of the first sealing system can also have a quadrilateral shape, such that it corresponds to the shape of the compression rod. For example, the gasket of the first sealing system can be located on the bottom surface of the hatch cover, such that when viewed from below, the gasket of the first sealing system can form a quadrilateral on the bottom surface of the hatch cover that corresponds to the shape of the compression rod.

[0024] The hatch cover may include an inner gasket channel (e.g., a steel channel) configured to receive a gasket from the first sealing system. The inner gasket channel may be on the bottom surface of the hatch cover. The inner gasket channel may be quadrilateral, such that the gasket of the first sealing system has a quadrilateral shape as described above.

[0025] The hatch coaming may include one or more side surfaces. These side surfaces may face a direction generally perpendicular to the main axis of the hatch opening. An expandable seal may be located on one or more side surfaces of the hatch coaming. For example, an expandable seal may be located on one or more side surfaces near the top of the hatch coaming, such that in the expanded state, the expandable seal abuts against the hatch cover to form a seal as described above.

[0026] By providing expandable seals on one or more side surfaces of the hatch coaming, the expandable seals can be spaced apart from a first sealing system that can be located on the top surface of the hatch coaming, and thus do not interfere with the operation of the first sealing system.

[0027] In some embodiments, the hatch coaming may include a channel configured to receive an expandable seal (e.g., a semi-tubular channel having a generally semi-circular cross-section). For example, one or more side surfaces of the hatch coaming may include the channel. For example, the channel may extend (e.g., continuously) around all sides of the hatch coaming. The channel may define an outwardly oriented opening. When expanding from an unexpanded state to an expanded state, the expandable seal may expand through the opening.

[0028] The passageway may be connected (e.g., attached) to the hatch coaming via a passageway support. The passageway support may extend away from the hatch coaming (e.g., in a direction generally perpendicular to the main axis of the hatch opening) such that the passageway is spaced apart from the hatch coaming (e.g., in a direction generally perpendicular to the main axis of the hatch opening). In some embodiments, one or more side surfaces of the hatch coaming may include the passageway support, for example, the passageway support may extend around all side surfaces of the hatch coaming (e.g., continuously). The passageway may be spaced apart from the hatch coaming (e.g., the passageway support extends from one or more side surfaces) by about 100 mm to about 500 mm, for example, about 150 mm to about 450 mm, for example, about 200 mm to about 400 mm, for example, about 250 mm to about 350 mm, for example, about 300 mm to about 350 mm, for example, about 300 mm. The channel may have a depth of approximately 20 mm to approximately 100 mm, for example, approximately 30 mm to approximately 90 mm, for example, approximately 40 mm to approximately 80 mm, for example, approximately 50 mm to approximately 70 mm, for example, approximately 50 mm to approximately 60 mm, for example, approximately 60 mm. Here, "channel depth" refers to the dimension of the channel extending from the channel opening, for example, in the direction perpendicular to the main axis of the hatch opening and / or in the direction of extension of the channel support on the side surface away from the hatch coaming. In embodiments where the channel is a semi-tubular channel, the semi-tubular channel may have a diameter of approximately 40 mm to approximately 200 mm, for example, approximately 60 mm to approximately 180 mm, for example, approximately 80 mm to approximately 160 mm, for example, approximately 100 mm to approximately 140 mm, for example, approximately 100 mm to approximately 120 mm, for example, approximately 120 mm.

[0029] One or more side surfaces of the hatch coaming may be one or more outer surfaces of the hatch coaming, such that the one or more side surfaces are away from the hatch opening (e.g., towards the flange of a bulk carrier). In other words, the one or more side surfaces may be oriented outward.

[0030] By providing an expandable seal on the outer surface of the hatch coaming, the second sealing system provides a seal between the hatch coaming and the hatch cover during use, isolating the first sealing system from the external environment. As a result, the second sealing system reduces the likelihood of damage to the first sealing system due to weathering or corrosion.

[0031] The second sealing system can extend around all connection areas between the hatch cover and the hatch coaming. For example, an expandable seal (e.g., and a channel configured to receive the expandable seal) can extend completely around the hatch coaming and the hatch opening.

[0032] In embodiments where the hatch opening has a quadrilateral shape (as described above), the expandable seal may extend (e.g., continuously) along each side of the quadrilateral shape. In these embodiments, the hatch coaming may include an expandable seal (e.g., and a channel for receiving the expandable seal) on each side of the quadrilateral shape.

[0033] Bulk carriers (like all ships) have a centerline. In embodiments where the hatch openings are quadrilateral in shape, the quadrilateral shape can be generally aligned with the centerline of the bulk carrier. In other words, the hatch openings can have four sides facing forward, stern, port, and starboard respectively. Furthermore, other features having corresponding quadrilateral shapes (as described above) can similarly be aligned with the centerline of the bulk carrier. For example, hatch coamings can have four outer surfaces facing forward, stern, port, and starboard respectively.

[0034] The hatch cover may include a skirt. The skirt may extend away from the hatch cover, for example, from the bottom surface of the hatch cover. For example, the hatch cover may include a skirt that, in use, extends from the bottom surface of the hatch cover toward the hatch opening. The skirt may resemble a plate attached to the hatch cover (e.g., attached to the bottom surface of the hatch cover), which is generally perpendicular to the hatch cover. For example, the skirt may include a plate forming a continuous loop that extends from and is generally perpendicular to the hatch cover. The skirt may include one or more side surfaces facing a direction generally perpendicular to the main axis of the hatch cover.

[0035] In use, the skirt can extend around the entire perimeter of the hatch opening. The shape of the skirt (when viewed from below) can be mathematically similar to the shape of the hatch coaming (when viewed from above). In embodiments where the hatch coaming is quadrilateral when viewed from above, the skirt can be a complementary quadrilateral when viewed from below.

[0036] In use, the skirt (e.g., one or more side surfaces of the skirt) may overlap with the hatch coaming (e.g., one or more side surfaces of the hatch coaming). In a preferred embodiment, the hatch coaming may be located on the side of the skirt closest to the hatch opening. In these embodiments, the skirt can be considered to be located outside the hatch coaming because it lies between the hatch coaming and the external environment. The spacing between the hatch coaming and the skirt may be uniform around the hatch opening.

[0037] When the hatch opening is closed by the hatch cover, the inner gasket channel (and gasket) can be positioned within the skirt such that the skirt is positioned between the inner gasket channel and the edge of the hatch cover. The outer wall of the inner gasket channel (e.g., the wall closest to the edge of the hatch cover) can be adjacent to (e.g., connected to and optionally aligned with) the skirt such that the gasket of the first sealing system is adjacent to (e.g., connected to) the skirt.

[0038] By providing a hatch cover with a skirt, which extends from the bottom surface of the hatch cover toward the hatch opening during use, seals and sealing systems can be more easily installed between the hatch cover and the hatch coaming. Furthermore, a longer and / or more complex path can be provided between the external environment and the hatch opening, thereby reducing the likelihood of water entering the cargo hold via the hatch opening. Specifically, by providing a skirt on the outside of the hatch coaming during use, the path for water ingress requires water to travel upwards before passing the top of the hatch coaming. Moreover, by positioning the skirt on the outside of the hatch coaming during use, the primary sealing system and the expandable seal are protected from the external environment by the skirt. This increases the lifespan of the sealing system by reducing damage caused by weathering and / or corrosion.

[0039] The skirt can extend from the bottom of the hatch cover by about 100mm to about 400mm, for example about 150mm to about 350mm, for example about 200mm to about 300mm, for example about 200mm to 300mm, for example about 270mm.

[0040] The skirt may include one or more reinforcing members. These reinforcing members may be disposed on one or more side surfaces of the skirt, such as one or more outer surfaces. The one or more outer surfaces of the skirt refer to one or more side surfaces that, in use, face away from the hatch opening. Multiple reinforcing members may be spaced apart from each other along the skirt. The reinforcing members may extend away from the bottom surface of the hatch cover. This reinforcing member is called a support.

[0041] The skirt (e.g., one or more side surfaces of the skirt) may include wedge-shaped notches around its perimeter. Some or all of the multiple reinforcing members may include corresponding wedge-shaped notches.

[0042] In embodiments where the skirt overlaps with the hatch coaming during use, when in an inflated state, the expandable seal abuts against the skirt (e.g., one or more side surfaces of the skirt) and the hatch coaming (e.g., one or more side surfaces of the hatch coaming). For example, in embodiments where the expandable seal is located on one or more outer surfaces of the hatch coaming and the skirt is positioned to the outside of the hatch coaming, the expandable seal abuts against the skirt and adapts to the shape of the skirt (e.g., the shape of one or more side surfaces of the skirt) to provide a seal between the hatch cover and the hatch coaming. In other words, the second sealing system may include an expandable seal and a skirt such that, in an inflated state, the expandable seal abuts against the skirt to provide a seal between the hatch coaming and the hatch cover.

[0043] By providing a second sealing system comprising an expandable seal and a skirt, the expandable seal, when inflated, abuts against the skirt and conforms to its shape, thereby providing a seal between the hatch cover and the hatch coaming. The skirt provides a surface against which the expandable seal abuts to form a high-quality seal. Furthermore, the skirt provides protection for the expandable seal against the external environment.

[0044] As described above, the hatch cover is moved into position such that after cargo is loaded into the cargo hold through the hatch opening, the hatch cover is positioned on the hatch coaming. Before being moved into position, the hatch cover is positioned adjacent to the hatch opening such that the hatch opening is uncovered (referred to as the uncovered state). The cargo hatch can reversibly switch between a covered state (where the hatch cover is above the hatch opening) and an uncovered state. The hatch cover can move between the covered and uncovered states in a direction generally parallel to the centerline of the bulk carrier.

[0045] In the covered state, the hatch cover is positioned above the hatch opening but not on the hatch coaming. Therefore, the cargo hatch can be reversibly moved (e.g., lowered and raised) between the covered and closed states.

[0046] To ensure that the hatch cover is correctly in its closed position when the cargo hatch is closed, the cargo hatch may include a device for correctly positioning the hatch cover, such as a wedge slider.

[0047] The hatch coaming may include one or more friction pads (bearing pads) to support the hatch cover. For example, the top surface of the hatch coaming may include multiple (e.g., four) friction pads to support the hatch cover. One or more friction pads may be bolted or welded to the hatch coaming. The hatch cover may support the compression rods (or multiple compression rods) described herein via individual washers and also support the friction pads.

[0048] Hatch covers can be mounted on tracks, such as wheel rails, allowing the hatch covers to move along the tracks to switch between covered and uncovered states. For example, a cargo hatch may include two tracks. The tracks may extend generally parallel to the centerline of the bulk carrier. One track may be located on the starboard side of the hatch opening, and the other track may be located on the port side of the hatch opening. Hatch covers may include wheels. One or more wheels may be configured to run along the corresponding tracks, for example, to be stationary and rolling on the corresponding tracks. For example, a hatch cover may include two wheels configured to be stationary and rolling on the starboard track and two wheels configured to be stationary and rolling on the port track. In some embodiments, a hatch cover may include four such wheels, for example, located near the various corners of the hatch cover.

[0049] One or more motors may be used to drive the wheels along the track. The hatch cover may include one or more motors. For example, each wheel may have a corresponding motor. The track and wheels may have teeth (e.g., making the track resemble a rack and pinion and the wheels resemble cooperating small gears).

[0050] When the hatch cover is to be closed, it can be moved above the hatch opening, for example, by moving it along a track. At this stage, the cargo hatch is covered but not yet closed. The hatch may include means for lowering the hatch cover onto the hatch coaming. For example, one or more hydraulic jacks may be provided to lower the hatch cover onto the hatch coaming. For example, four hydraulic jacks may be provided, such as one at each corner of the hatch cover. Thus, the hatch cover can be positioned on the hatch coaming (e.g., so that the hatch is closed), and the sealing system can then operate as described herein.

[0051] When access to the cargo hold is required, the hatch cover can be raised (e.g., by hydraulic jacks) to change the cargo hatch from a closed state to a covered state, and then moved away from the hatch opening (e.g., by rails) to change the cargo hatch from a covered state to an uncovered state.

[0052] In use, the hatch cover may extend beyond the hatch opening, such as the hatch coaming. For example, in use, the hatch cover may extend laterally beyond the hatch opening, such as towards the port and / or starboard side of a bulk carrier. In some embodiments, in use, one or more portions of the hatch cover extending beyond the hatch opening may cover a portion of the crew passage and / or a working space adjacent to the hatch opening. The working space may be located between the crew passage and the hatch coaming (e.g., on one or both sides of the bulk carrier).

[0053] In embodiments where the hatch cover extends beyond the hatch coaming, one or more edges of the hatch cover (in use) may connect to (e.g., located at) a support area of ​​the bulk carrier. For example, the support area may be part of the bulk carrier's deck. In some embodiments, an additional sealing system may be provided between the hatch cover and the support area (e.g., the bulk carrier's deck). This additional sealing system may include a gasket and a compression bar. For example, the support area (e.g., the deck) may include a compression bar, and the hatch cover may include an additional gasket for the additional sealing system. In use, the gasket of the additional sealing system may abut (e.g., located at) the compression bar in the support area and be shaped to fit the compression bar, thereby providing a seal between the hatch cover and the support area. The seal can be maintained by a downward force of the hatch cover on the compression bar.

[0054] The support area of ​​a bulk carrier can extend completely around the hatch opening. An additional sealing system can extend between all connection areas between the hatch cover and the support area of ​​the bulk carrier. For example, the compression bar of the additional sealing system can extend completely around the hatch opening. In these embodiments, the gasket of the additional sealing system can extend completely around the area of ​​the hatch cover that corresponds to the area of ​​the hatch cover connected to the compression bar of the additional sealing system when the hatch cover is closed. For example, the gasket of the additional sealing system can extend completely around the perimeter of the hatch cover. The shape of the gasket of the additional sealing system (when viewed from below) can correspond to the shape of the compression bar on the support area, such as the deck of a bulk carrier (when viewed from above).

[0055] The compression rod of the additional sealing system can have a quadrilateral (e.g., rectangular) shape (when viewed from above) such that it surrounds the hatch opening. The corresponding gasket of the additional sealing system can also have a quadrilateral shape such that it corresponds to the shape of the compression rod of the additional sealing system. For example, if the hatch cover is quadrilateral, the gasket of the additional sealing system can extend along the edge of the hatch cover on the bottom surface, thus also having a quadrilateral shape.

[0056] The hatch cover may include an external gasket channel, such as a steel channel, configured to receive a gasket for an additional sealing system. The external gasket channel may be on the bottom surface of the hatch cover. The external gasket channel may have a quadrilateral shape, such that the gasket for the additional sealing system has a quadrilateral shape as described above.

[0057] In a second aspect, a bulk carrier is provided that includes one or more cargo hatches according to the first aspect. In some embodiments, the bulk carrier according to the second aspect may include more than one cargo hatch according to the first aspect, each cargo hatch including a corresponding hatch cover configured to be removably positioned on a corresponding hatch coaming such that the hatch cover reversibly closes the hatch opening (e.g., the entire hatch opening).

[0058] According to the second aspect, hatch covers on bulk carriers can be moved in a direction generally parallel to the centerline of the bulk carrier in order to cover or not cover the hatch openings.

[0059] In a third aspect, a method for closing a cargo hatch for a bulk carrier is provided, the method comprising the steps of: removably positioning a hatch cover on a hatch coaming of the cargo hatch; providing a first seal between the hatch coaming and the hatch cover using a first sealing system, wherein the first sealing system includes a gasket and a compression rod (e.g. on opposing surfaces of the hatch coaming and the hatch cover); and providing a second sealing system including an expandable seal, such that the expandable seal expands to provide a second seal between the hatch coaming and the hatch cover.

[0060] The steps of removably positioning a hatch cover on a hatch coaming of a cargo hatch may include: moving the hatch cover above the hatch opening (e.g., causing the cargo hatch to switch between an uncovered state and a covered state), and lowering the hatch cover so that it is positioned on the hatch coaming.

[0061] In order to provide access to the cargo holds of a bulk carrier via the hatch opening, the method according to the third aspect may further include the steps of: collapsing an expandable seal to remove a second seal, and moving the hatch cover away from the hatch coaming so that the hatch opening is accessible.

[0062] Moving a hatch cover above the hatch opening can include, for example, moving the hatch cover in a direction generally parallel to the centerline of the bulk carrier.

[0063] This invention includes combinations of the described aspects and preferred features, unless such combinations are obviously not permitted or explicitly avoided. For example, the method of the third aspect may involve a method of closing a cargo hatch according to the first aspect.

[0064] Throughout this specification, references to the cargo hatches of the first aspect on bulk carriers are made. However, it should be understood that cargo hatches of the first aspect can also be located on any type of vessel, not just bulk carriers. Therefore, those skilled in the art will understand that references to bulk carriers are also references to any other vessel.

[0065] In this specification, "viewed from above" means viewed facing the deck of a bulk carrier. In the context of hatch covers and their components (such as skirts and gaskets), "viewed from below" means viewed facing the bottom surface of the hatch cover. Attached Figure Description

[0066] Embodiments and examples illustrating the principles of the invention will now be discussed with reference to the accompanying drawings, in which:

[0067] Figure 1A top view of a bulk carrier with cargo hatches according to the first aspect is shown, wherein the cargo hatches are shown to be uncovered.

[0068] Figure 2 It shows Figure 1 The rear view of the hatch cover of the cargo hatch shown.

[0069] Figure 3 Shown from the starboard side Figure 2 A side view of the hatch cover.

[0070] Figure 4 It shows Figure 2 Bottom view of the hatch cover of the cargo hatch shown.

[0071] Figure 5 It shows Figure 1 A top view of a bulk carrier, with the cargo hatches shown as covered.

[0072] Figure 6 It shows Figure 1 The cross-sectional view of the starboard side of the bulk carrier shows the cargo hatches covered.

[0073] Figure 7 It shows Figure 1 The cross-sectional view of the bulk carrier shows the cargo hatches closed. Detailed Implementation

[0074] Various aspects and embodiments of the invention will now be discussed with reference to the accompanying drawings. Other aspects and embodiments will also be apparent to those skilled in the art. All references herein are incorporated by way of citation.

[0075] Figure 1 A top view of the longitudinal portion of a bulk carrier having a cargo hatch 100, according to the first aspect, is shown.

[0076] The bulk carrier 1 has a starboard upper ballast tank 2 and a port upper ballast tank 3, which are separated by a section of deck 4 through which a cargo hatch 100 is located. The two upper ballast tanks 2 and 3 are separated from the section of deck 4 with the cargo hatch 100 by corresponding longitudinally extending crew passages 5a and 5b. The cargo hatch 100 is symmetrical about the centerline 91 of the bulk carrier 1.

[0077] Although only one cargo hatch 100 is shown in the accompanying drawings, the bulk carrier 1 may have more than one cargo hatch 100, each having the same or similar structure as the cargo hatch 100 described herein. Each cargo hatch 100 is generally spaced apart from other cargo hatches along the centerline 91 of the bulk carrier 1 (i.e., in the longitudinal direction).

[0078] Cargo hatch 100 has a hatch opening 101, which is a rectangular opening in the deck 4 of the bulk carrier 1. The hatch opening 101 allows cargo to be loaded through the hatch opening and into the cargo holds of the bulk carrier.

[0079] The hatch coaming 110 surrounds the hatch opening 101 such that it extends around the entire perimeter of the hatch opening 101. As those skilled in the art will understand, the hatch coaming 110 includes a flat surface / plate extending vertically around the hatch opening 101. Here, the hatch coaming 110 is analogous to the side of a cuboid such that it surrounds the entire perimeter of the hatch opening 101.

[0080] exist Figure 1 In the image, cargo hatch 100 is shown uncovered, with hatch cover 130 located near hatch opening 101 and facing the stern of the bulk carrier, allowing access to the cargo hold via hatch opening 101. For clarity, in Figure 1 The image shows the components below the hatch cover 130.

[0081] Hatch cover 130 is mounted on two longitudinally extending wheel rails 20a and 20b, which are located on the corresponding sides of hatch opening 101. When viewed from above, hatch cover 130 has a larger area than hatch opening and extends across crew passageways 5a and 5b on the port and starboard sides. Hydraulic jacks 120a, 120b, 120c, and 120d are provided near each corner of hatch opening 101 and aligned with wheel rails 20a and 20b.

[0082] Figure 2 It shows Figure 1 The diagram shows a stern view of hatch cover 130. Hatch cover 130 is a flat plate (e.g., a metal such as steel). In this embodiment, hatch cover 130 has a thickness of approximately 450 mm, a width of approximately 19 m, and a length (in the longitudinal direction) of approximately 11.5 m. Those skilled in the art will understand that the dimensions of hatch cover 130 may vary depending on the dimensions of cargo hatch 100 and / or bulk carrier 1.

[0083] The hatch cover 130 includes a skirt 131 extending from the bottom surface of the hatch cover 130. The skirt 131 extends around the periphery of the hatch cover 130 and is spaced inwardly from the edge of the hatch cover 130. The hatch cover 130 has a main axis extending vertically through the center of the hatch cover 130. The skirt 131 includes an outer surface 134 that, in use, faces a direction generally perpendicular to the main axis of the hatch cover. The outer surface 134 of the skirt 131 can be considered to include four consecutively connected outer surfaces 134 facing different directions (forward, stern, port, and starboard). Figure 2The outer surface 134 of the skirt 131 facing the tail is shown. The skirt includes a plurality of reinforcing members 135 spaced apart along the skirt 131 on the outer surface 134. The reinforcing members 135 (which may resemble ribs) extend away from the bottom surface of the hatch cover 130.

[0084] Figure 3 A side view of the hatch cover 130, viewed from the starboard side, is shown. Here, the outer surface 134 of the skirt 131 facing the starboard side can be seen to have reinforcing members 135 spaced apart therefrom.

[0085] The hatch cover 130, located below (attached to the bottom surface), includes four wheels 121a, 121b, 121c, and 121d. Each wheel is positioned between the skirt 131 and the side of the hatch cover 130. Figure 3 As shown, there are two wheels 121a and 121b on the starboard side, which are laterally aligned and longitudinally spaced from each other. There are also two wheels 121c and 121d on the port side, which are similarly laterally aligned and longitudinally spaced from each other (see...). Figure 4 Starboard side wheels 121a and 121b are mounted on starboard side rails 20a, and port side wheels 121c and 121d are mounted on port side rails 20b, allowing the hatch cover 130 to be movably supported on rails 20a and 20b. Wheels 121a, 121b, 121c, and 121d are configured to roll along rails 20a and 20b, enabling the hatch cover 130 to move along the rails. Each wheel 121a, 121b, 121c, and 121d is equipped with a corresponding motor 122a, 122b, 122c, and 122d, which drives wheels 121a, 121b, 121c, and 121d, causing the hatch cover 130 to move along rails 20a and 20b.

[0086] Figure 4 The hatch cover 130 is shown as a view from below. Figure 4 In the middle, near the corner of hatch cover 130, all four wheels 121a, 121b, 121c, 121d and their corresponding motors 122a, 122b, 122c, 122d can be seen. For example... Figure 4 As shown, when viewed from below, skirt 131 is rectangular.

[0087] The hatch cover 130 includes an inner gasket channel 132 disposed inside a skirt 131, such that the skirt 131 is positioned between the inner gasket channel 132 and the edge of the hatch cover 130. The inner gasket channel 132 extends completely around the interior of the skirt 131. When viewed from below, the inner gasket channel 132 follows a path having a corresponding rectangular shape. The outer wall of the inner gasket channel 132 is aligned with the skirt 131. The inner gasket channel 132 is configured to receive an inner gasket.

[0088] The hatch cover 130 also includes an outer gasket channel 133 that extends around the periphery of the bottom surface of the hatch cover 130 at its peripheral edge. When viewed from below, the outer gasket channel 133 also follows a rectangular path. The outer gasket channel 133 is configured to receive an outer gasket.

[0089] Figure 4 The hatch cover 130 shown is in Figure 4 The directions shown exhibit both horizontal and vertical symmetry.

[0090] The operation of cargo hatch 100 will be described next.

[0091] As explained above, Figure 1 The cargo hatch 100 is shown uncovered. Figure 5 In the diagram, the cargo hatch 100 is shown in a covered state, such that the hatch cover 130 is positioned above the hatch opening 101 (in Figure 5 (For clarity, the components below hatch cover 130 are shown in the image). Hatch cover 130 is located in... Figure 1 The uncovered state shown and Figure 5 The hatch cover 130 can be moved reversibly between the shown covered states. This is achieved by moving the hatch cover 130 along the wheel rails 20a and 20b on wheels 121a, 121b, 121c and 121d driven by motors 122a, 122b, 122c and 122d.

[0092] When covered, the hatch cover 130 is positioned above the hatch opening 101. Figure 6 A cross-sectional view of the starboard side of a bulk carrier is shown, in which cargo hatch 100 is covered (i.e., cargo hatch 100 is covered but not closed).

[0093] Figure 6 Three sealing systems are shown: a first sealing system 140; a second sealing system 150; and an additional sealing system 160.

[0094] The first sealing system 140 includes an inner gasket 141 received in an inner gasket channel 132 of the hatch cover. The first sealing system 140 also includes an inner compression rod 142 located at the top of the hatch coaming 110. The compression rod 142 extends completely around the top of the hatch coaming 110, such that when viewed from above, the compression rod 142 is rectangular in shape (similar to the hatch coaming 110). When the cargo hatch 100 is in a position such as... Figure 6 In the covered state shown, the inner washer channel 132 is vertically aligned with the compression rod 142.

[0095] The second sealing system 150 includes an expandable seal 151 and a skirt 131 of the hatch cover 130. The expandable seal 151 is housed in a semi-tubular channel 158 located on the outer surface 111 of the hatch coaming 110, near the top of the hatch coaming 110. Specifically, the outer surface 111 of the hatch coaming 110 has a channel support 159 extending outward away from the hatch coaming 110 (in a direction generally perpendicular to the main axis 101 of the hatch opening 101). The semi-tubular channel 158, having a semi-circular cross-section, is located at the end of the channel support 159, such that it is positioned approximately 300 mm from the hatch coaming 110. The semi-tubular channel 158 extends completely around the hatch coaming 110. The radius of the semi-tubular channel 158 is approximately 60 mm.

[0096] The expandable seal 151 is configured to reversibly expand from an unexpanded state to an expanded state. When expanding from an unexpanded state to an expanded state, the expandable seal 151 expands through an outward-facing opening 157 in a semi-tube passage 158 away from the hatch coaming 110.

[0097] The additional sealing system 160 includes an outer gasket 161 received in an outer gasket channel 133 of the hatch cover 130. The additional sealing system 160 also includes an outer compression rod 162 located on the deck 4 of the bulk carrier 1. When viewed from above, the outer compression rod 162 is rectangular, such that when the cargo hatch 100 is in a position as shown in the image... Figure 6 In the covered state, the outer gasket channel 133 is vertically aligned with the compression rod 162. In other words, when the cargo hatch 100 is covered, each portion of the outer gasket channel 133 is vertically aligned with a portion of the compression rod 162. As a result, the outer compression rod 162 surrounds and is spaced apart from the hatch opening 101 and the hatch coaming 110.

[0098] Figure 7 A cross-sectional view of bulk carrier 1 is shown. Figure 7 In the diagram, cargo hatch 100 is shown in the closed state, with hatch cover 130 positioned on hatch coaming 110. To close cargo hatch 100, cargo hatch 100 is... Figure 6 The coverage status shown has decreased to Figure 7 The hatch cover 130 is shown in the closed position. Specifically, the hatch cover 130 is lowered from its covered position to the closed position (on the hatch coaming 110) by hydraulic jacks 120a, 120b, 120c, and 120d. As those skilled in the art will understand, in the closed position, the hatch cover 130 can be secured in a conventional manner, for example by clamps provided around the skirt 131.

[0099] In the closed state, the inner gasket 141 of the first sealing system 140 is positioned on the inner compression rod 142. Under the weight of the hatch cover 130, the inner gasket 141 adapts to the shape of the inner compression rod 142, thereby providing a waterproof seal between the hatch cover 130 and the hatch coaming 110, thus sealing the cargo hold against the external environment.

[0100] In the closed state, the outer gasket 161 of the additional sealing system 160 rests on the outer compression rod 162. Under the weight of the hatch cover 130, the outer gasket 161 adapts to the shape of the outer compression rod 162, thereby providing an additional seal between the hatch cover 130 and the deck 4. Thus, the additional sealing system provides a waterproof seal between the crew passages 5a, 5b and the external environment.

[0101] In the closed state, the skirt 131 of the hatch cover 130 tightly surrounds the hatch coaming 110. When viewed from below, the shape of the skirt 131 is mathematically similar to the shape of the hatch coaming 110 when viewed from above (i.e., the rectangular shape in the illustrated embodiment). The proximity of the hatch coaming 110 and the skirt 131 facilitates the formation of the second sealing system 150.

[0102] In a condition where the cargo hatch is never covered (e.g.) Figure 1 (As shown) transition to covered state (e.g.) Figure 5 and Figure 6 (as shown), then to the off state (as shown) Figure 7 During the period shown, the expandable seal 151 remains in an unexpanded state. When the cargo hatch 100 is closed, the expandable seal 151 expands from an unexpanded state to an expanded state through the opening 157 of the semi-tube passage 158, causing it to abut against the skirt 131. When expanded in this manner, the expandable seal 151 adapts to the shape of the skirt 131, thereby providing a seal between the hatch cover 130 and the hatch coaming 110. Therefore, the second sealing system 150 provides a waterproof seal between the hatch opening 101 and the external environment. Furthermore, since the second sealing system 150 is located outside the first sealing system 140, the second sealing system 150 protects the first sealing system 140.

[0103] When access to the cargo hold is desired via hatch opening 101, the expandable seal 151 collapses from an expanded state to an unexpanded state, and hydraulic jacks 120a, 120b, 120c, and 120d operate to raise hatch cover 130, causing cargo hatch 100 to change from a closed state to a covered state. Hatch cover 130 then moves along wheel rails 20a and 20b, leaving hatch opening 101 uncovered (i.e., cargo hatch 100 changes from a covered state to an uncovered state).

[0104] It should be understood that the expandable seal 151 can expand in various different ways. In some embodiments, for example, the expandable seal 151 is pneumatically expanded by inflating it by introducing a certain amount of expanding gas into its internal volume. In some such examples, the inflating gas can be air, and can be introduced into the expandable seal in a known manner via a compressor device 180. As will be understood, such embodiments may further include a ventilation device configured to ventilate the internal volume of the expandable seal 151 to release the inflated air and thereby change the expandable seal 151 from its expanded state back to its unexpanded state.

[0105] Contemplate alternative embodiments in which the expandable seal 151 is hydraulically expanded by directing a suitable amount of hydraulic fluid into the internal volume of the expandable seal 151. In some such arrangements, the hydraulic fluid may be located within a closed hydraulic circuit (not shown) comprising a reservoir in fluid communication with the internal volume of the expandable seal 151 and one or more fluid conduits. A reversibly operable hydraulic pump may be provided to i) pump hydraulic fluid from the reservoir into the internal volume of the expandable seal 151 to expand the expandable seal 151, and ii) pump hydraulic fluid from the internal volume of the expandable seal 151 into the reservoir to collapse the expandable seal 151.

[0106] Figure 7 The workspaces 6a and 6b located between the hatch coaming 110 and the corresponding crew passages 5a and 5b are also shown.

[0107] exist Figure 6 and Figure 7 The diagram shows the main axis 92 of the hatch opening 101. Figure 2 and Figure 3 The diagram shows the main axis 93 of the hatch cover 130. These main axes are parallel to the vertical axis of the bulk carrier. In this specification, references to vertical, top, bottom, etc., refer to directions when the bulk carrier is in its normal upright position, such as in a dock. In other words, when the centerline of the bulk carrier is horizontal, the longitudinal axis of the hatch opening is vertical (e.g., as shown in the figure). Those skilled in the art will understand that the orientation of the bulk carrier and cargo hatches may change when, for example, the bulk carrier is at sea. Therefore, any direction mentioned should not be construed as limiting the invention to the orientation of the cargo hatches shown in the figure.

[0108] The features disclosed in the foregoing description, or in the appended claims, or in the drawings, are expressed in their particular form or as means for performing the disclosed functions or as methods or processes for obtaining the disclosed results, and, as appropriate, may be used alone or in any combination of these features to implement the invention in various forms.

[0109] Although the present invention has been described in conjunction with the exemplary embodiments described above, many equivalent modifications and variations will become apparent to those skilled in the art when the invention is presented. Therefore, the exemplary embodiments of the invention set forth above should be considered illustrative rather than restrictive. Various changes can be made to the described embodiments without departing from the spirit and scope of the invention.

[0110] To avoid any ambiguity, any theoretical explanations provided herein are intended to enhance the reader's understanding. The inventor does not wish to be bound by any of these theoretical explanations.

[0111] The headings of any section used in this article are for organizational purposes only and are not intended to limit the subject matter described.

[0112] Throughout this specification, including the appended claims, unless the context otherwise requires, the words “comprising” and “including” and variations thereof shall be construed as implying the inclusion of the stated number or step or number or group of steps, but not excluding any other number or step or number or group of steps.

[0113] It must be noted that the singular forms “the” and “the” used in the specification and appended claims include the plural forms unless the context clearly specifies otherwise. A range herein may be expressed as from “about” a particular value and / or to “about” another particular value. When such a range is expressed, another embodiment includes from one particular value and / or to another particular value. Similarly, by using the antecedent “about” when a value is expressed as an approximation, it will be understood that the particular value forms another embodiment. The term “about” in relation to numerical values ​​is optional and may mean, for example, + / - 10%.

Claims

1. A cargo hatch (100) for a bulk carrier (1), comprising: A hatch coaming (110) surrounds a hatch opening (101) having a main axis extending in the vertical direction; A hatch cover (130) is configured to be removably positioned on the hatch coaming such that the hatch cover reversibly closes at least a portion of the hatch opening; A first sealing system (140) includes a gasket (141) and a compression rod (142) and is configured to provide a seal between the hatch coaming and the hatch cover in the closed state; and The second sealing system (150) includes an expandable seal (151) and is configured to provide a seal between the hatch coaming (110) and the hatch cover (130) in the closed state. The hatch coaming includes a side surface (111) facing a direction substantially perpendicular to the main axis of the hatch opening. The expandable seal (151) is located on the side surface of the hatch coaming, near the top of the hatch coaming (110), such that in the expanded state, the expandable seal abuts against the hatch cover (130) to form a seal in the closed state.

2. The cargo hatch according to claim 1, wherein, The expandable seal (151) is a reversible expandable seal.

3. The cargo hatch according to claim 1 or 2, wherein, The expandable seal (151) is an inflatable seal.

4. The cargo hatch according to any one of the preceding claims, wherein, The side surface (111) is the outer surface facing away from the hatch opening.

5. The cargo hatch according to any one of the preceding claims, wherein, The hatch cover includes a skirt (131) that extends from the bottom surface of the hatch cover (130) toward the hatch opening (101) so as to overlap with the hatch coaming (110) in the closed state.

6. The cargo hatch according to claim 5, wherein, In use, the skirt (131) is located on the outside of the hatch coaming.

7. The cargo hatch according to claim 5 or 6, wherein, The second sealing system (150) includes the skirt (131) such that, in an inflated state, the inflatable seal (151) abuts against the skirt (131) to provide a seal between the hatch coaming (110) and the hatch cover (130).

8. The cargo hatch according to any one of the preceding claims, wherein, The hatch cover (130) is configured to be removably positioned on the hatch coaming (110) such that the hatch cover reversibly closes the entire hatch opening (101).

9. The cargo hatch according to any one of the preceding claims, wherein, The hatch cover (130) is movable between a covered position and an open position in a direction generally parallel to the centerline of the bulk carrier (1), wherein the hatch opening (101) is covered by the hatch cover in the covered position and the hatch opening is not covered in the open position.

10. A bulk carrier comprising one or more cargo hatches according to any one of claims 1 to 9.

11. A method for closing a cargo hatch (100) according to any one of claims 1 to 9, the method comprising the steps of: The hatch cover (130) is removably positioned on the hatch coaming (110) of the cargo hatch; A first seal is provided between the hatch coaming and the hatch cover using a first sealing system (140) including a gasket (141) and a compression rod (142); Provides a second sealing system (150) including an expandable seal (151); and The expandable seal is expanded to provide a second seal between the hatch coaming and the hatch cover.

12. The method according to claim 11, wherein, The step of removably positioning the hatch cover on the hatch coaming of the cargo hatch includes the following steps: moving the hatch cover (130) above the hatch opening (101) in a direction generally parallel to the centerline of the bulk carrier, and lowering the hatch cover so that the hatch cover is positioned on the hatch coaming (110).

13. The method according to any one of claims 11 and 12, comprising the following steps: The expandable seal (151) is collapsed, thereby removing the second seal; Move the hatch cover (130) away from the hatch coaming (110) so that the hatch opening (101) is accessible.

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