269results about "Vessel hatches/hatchways" patented technology

The utility model relates to the technical field of ships, in particular to a ship hatch cover convenient to open and close. The device comprises a hatch cover installed on a hatch through a rotating seat, the hatch cover is provided with a light energy power generation assembly and a battery protection shell, a battery is arranged in the battery protection shell, and the light energy power generation assembly is electrically connected into the battery; a vacuum locking structure and an air pressure unlocking structure are arranged in the cabin cover, an inductive switch is arranged on the inner side of the cabin cover, a handle is arranged on the cabin cover, and an opening button connected with the air pressure unlocking structure is arranged in the handle; according to the device, a vacuum locking structure is designed, the hatch cover is fixed in a low-pressure adsorption mode, a miniature vacuum pump is used for exhausting air, manual operation is not needed through control of an inductive switch, and use is convenient and fast; an air pressure unlocking structure is designed, so that complicated manual operation is not needed; the solar power generation assembly is designed, solar energy is used for power generation, and therefore independent operation is achieved, external power supply is not needed, and stable operation can be guaranteed under special conditions.

The horizontal opening hatch cover device for the submersible comprises a hatch body, a cover body is installed on the hatch body in a sealed mode, a rotating support is installed outside the center position of the cover body through a rotating ring, a support is arranged beside the hatch body and connected with the rotating support through a rotating shaft, and the rotating support turns over around the rotating shaft. Therefore, the support is rotated to drive the cover body to be opened and closed. Two symmetrical hatch seats are installed on the hatch body, a wrench is installed on each hatch seat in a matched mode, a gear is arranged at the bottom of each wrench, arc-shaped racks are symmetrically arranged in the circumferential direction of the cover body, and the arc-shaped racks are meshed with the gears; a transmission mechanism is further installed outside the cover body and used for balancing air pressure on the two sides of the cover body, and work is stable and reliable.

The invention relates to the technical field of ship composite material structures and forming, and provides a super-large-span full-composite material hatch cover plate and a preparation method thereof. The hatch cover plate comprises a lower panel, a middle layer, an upper panel and an external connecting structure; the lower panel is attached to the upper panel through the middle layer to form a hatch cover plate body, the two ends of the hatch cover plate body are connected with an external connecting structure respectively, the hatch cover plate body is rapidly and conveniently connected with the external structure through the method that the main beam and the lattice structure are combined, and the force transmission supporting effect is achieved. The preparation method of the hatch cover plate comprises the following steps: step 1, forming the lower panel; 2, preparing an intermediate layer; step 3, paving an upper panel; fourthly, the main beam is connected with an external structure; pouring according to a vacuum integral forming process to obtain the required hatch cover plate; by means of the method, the span not smaller than 5 meters can be achieved, deformation is smaller than 2 mm under the self-weight working condition, and the hatch cover plate has the advantages of being light, high in strength, high in rigidity, designable in lattice structure, low in manufacturing cost, high in forming rate, low in process risk and the like.

The invention relates to the technical field of hatch cover locking, and discloses a deep sea manned submersible hatch cover locking device, which comprises a main body, the interior of the main body is hollow, and the deep sea manned submersible hatch cover locking device further comprises an auxiliary mechanism, and the auxiliary mechanism is arranged at the top of the main body and is used for enhancing the locking strength of the main body. According to the device, the locking force between the hatch cover and the main body can be automatically enhanced along with the increase of the water depth pressure, so that the locking force of the device is stronger along with the increase of the water depth; therefore, the situation that the locking force of the bolt on the hatch cover is loosened or weakened due to continuous change and impact of the flowing direction and pressure in water when the submersible dives and sails in the water can be reduced, and the locking strength during locking can be further enhanced.

The invention relates to an intelligent monitoring type bulk cargo ship electric hatch cover in the field of ships, through infrared distance sensors arranged on the splicing end faces of a left cover and a right cover, the opening and closing gap of the hatch cover is monitored in real time, a traditional multi-person opening and closing operation mode and a manual sealing state detection mode are replaced, and the operation efficiency is improved. The operation efficiency and the accuracy of detecting the sealing performance are improved; meanwhile, through an opening and closing monitoring system comprising an alarm module, an alarm is given out in time when a local gap is too large after the cover is closed, and an operator can conduct maintenance and disposal in time conveniently; besides, through arrangement of a wedge-shaped block, a wedge-shaped strip and a hydraulic cylinder, the left cover and the right cover are extruded and limited, and the splicing pressure of a splicing gap is adjusted in cooperation with a pressure sensor, so that the sealing effect of the left cover, the right cover and a splicing sealing strip is further improved; in addition, the leakage condition of the splicing position is monitored in real time through the leakage detection mechanism, and the leakage loss is reduced.

The utility model belongs to the technical field of ship equipment, and particularly relates to a hatch cover with a good closing effect. Comprising a cabin body, a cabin cover, a pressing piece and a spring lock, the upper end of the cabin cover extends inwards to form a bearing face, the bearing face extends upwards to form a connecting face, the pressing piece is installed on the bearing face, the cabin cover is arranged on the connecting face, the pressing piece is fixed to the cabin body, the spring lock comprises a locking piece and a connecting piece, the locking piece is arranged on the cabin cover, and the connecting piece is arranged on the locking piece. And the fixing piece is arranged on the cabin body. In the practical application, the hatch cover is pressed through the pressing piece and then is locked with the hatch body in cooperation with the spring lock, it is ensured that air or water leakage can be reduced when the hatch cover is closed, and it is ensured that the spring lock can be rapidly locked in place when the locking piece is used in cooperation with the connecting piece.

The utility model provides a hatch cover locking mechanism which comprises a frame body, one side of the frame body is fixedly connected with a supporting base, the inner wall of the supporting base is provided with a plurality of positioning insertion openings, one side of the supporting base is provided with a first connecting base, the first connecting base is fixedly connected with a hinge, the other end of the hinge is connected with a second connecting base, and the second connecting base is provided with a plurality of positioning insertion openings. The second connecting seat is connected with the hatch cover, a plurality of movable grooves are formed in the peripheral wall of the hatch cover, a rotating shaft is fixedly installed in the hatch cover, a movable ring is fixedly connected to the rotating shaft, a plurality of movable rods are fixedly connected to the movable ring, and the movable rods are correspondingly installed in the movable grooves; a plurality of movable rods are arranged on the outer wall of the hatch cover, the movable rods are connected with a rotating ring, the rotating ring is fixedly connected to the outer wall of the hatch cover, a plurality of movable blocks are arranged on the rotating ring, and the movable blocks and the positioning inserting openings are in an assembling relation, so that the hatch cover can be conveniently and rapidly fixed, and it is ensured that the hatch cover can be kept in a stable state even in a severe environment.

The large bottom cabin door comprises a cabin section structure, lifting oil cylinders are fixed to the two sides of the bottom of the cabin section structure respectively, a vertical T-shaped guide rail is fixed to the side face, beside the lifting oil cylinders, of the cabin section structure, and a sliding butt joint hook is arranged in the vertical T-shaped guide rail; the end part of the sliding butt-joint hook is connected with the output end of the lifting oil cylinder, and the sliding butt-joint hook slides up and down in the vertical T-shaped guide rail under the driving of the lifting oil cylinder; opening and closing connecting rod mechanisms are further fixed to the two sides of the bottom of the cabin section structure, pressure-resistant door plates are assembled below the opening and closing connecting rod mechanisms, opening and closing driving mechanisms are arranged on the upper portions of the opening and closing connecting rod mechanisms, and the opening and closing driving mechanisms drive the opening and closing connecting rod mechanisms to achieve opening and closing work of the pressure-resistant door plates, so that the pressure-resistant door plates can be retracted into the submersible vehicle. The device is not influenced by a seabed flow field and internal waves, can be in linear fit with an external light shell of a submersible vehicle when sailing on the seabed, is permeable in the whole course, and ensures the high-speed sailing capability.

The utility model relates to the technical field of hatch covers, and discloses a sealed hatch cover capable of being opened and closed on two sides, which comprises an end cover and a hatch seat, the end cover is arranged at the port of the hatch seat, a plurality of handles are fixed on the end face of the end cover, a threaded pipe is fixed on the inner wall of the hatch seat, a lead screw is arranged in the threaded pipe, and the end face of the threaded pipe is provided with a screw rod. The screw rod is in threaded engagement with the threaded pipe, a penetrating rod is arranged at the end, away from the end cover, of the screw rod in a penetrating mode, a warping plate is fixed to one end of the end cover, a fixing shaft is arranged on the warping plate, a supporting part is fixed to the outer wall of the hatch seat, and the fixing shaft is connected with the end, away from the outer wall of the hatch seat, of the supporting part in a rotating fit mode; the double-face opening and closing effect of the hatch cover can be achieved, namely the hatch cover can be opened inside and outside the cabin, a user can be assisted in opening the hatch cover inside the cabin, and the situation that the hatch cover is hard to open inside the cabin due to the fact that the hatch cover is too heavy is avoided.

The present invention relates to a submarine with at least one first opening 130 between the interior of the submarine and the surrounding water area, wherein the first opening 130 is connected to a first cover 120, wherein the first opening 130 can be closed with the first cover 120, wherein the first cover 120 is rotatably mounted about a first axis of rotation 70, wherein the submarine has a first rotary drive 10, wherein the first rotary drive 10 is placed on a second axis of rotation 80 and its drive shaft is rotatably mounted thereon, wherein the first axis of rotation 70 and the second axis of rotation 80 are parallel and offset from each other, wherein the first rotary drive 10 and the first cover 120 are frictionally connected via a first linkage 20, wherein the first linkage 20 comprises a first crank 50, a first rocker arm 40 and a first coupling 60.wherein the first rotary drive 10 is frictionally connected to the first crank 50, wherein the first crank 50 is rotatably mounted about the second axis of rotation 80, wherein the first cover 120 is frictionally connected to the first rocker arm 40, wherein the first rocker arm 40 is rotatably mounted about the first axis of rotation 70, wherein the first crank 50 and the first rocker arm 40 are frictionally connected to each other via the first coupling 60, wherein the first rocker arm 40 is rotatably connected to the first coupling 60, wherein the first crank 50 is rotatably connected to the first coupling 60.

The present invention discloses a manhole cover mechanism, which relates to the technical field of container accessories, including a cover seat and a cover plate, wherein a pin lock assembly capable of being locked with the cover plate is slidably mounted on the cover seat, a power unit capable of being driven in forward and reverse directions is transmission-connected to the cover plate, a slide assembly is mounted on the cover seat, the slide assembly comprises a slide structure arranged on the cover seat, the slide structure has a first limit end and a second limit end, a sliding body is slidably adapted between the first limit end and the second limit end, the sliding body is connected to the power unit, the pin lock assembly is connected to the sliding body, and the pin lock assembly can complete the switching of the locking state as the reaction force generated by the power unit is driven in forward and reverse directions. During the whole process, the present invention does not need to control two power units separately, thereby simplifying the operation steps and improving the simplicity of operation.

A method and system for fumigating a vessel includes delivering a fumigation agent to a cargo area of ​​the vessel. In particular, the vessel may be a roll-on / roll-off vessel. In such a system, a pneumatic system is provided for maintaining a selected minimum pressure differential between a selected area of ​​the vessel above the cargo area and the cargo area such that the pressure in the selected area is greater than the cargo area. A control system may maintain the pressure differential.

The bulk cargo ship comprises the ship body, a hatch, lateral moving sliding rails, a hatch cover module, an outer cover plate, a rotating shaft, an inner cover plate and wing cover plates, the hatch cover module is divided into the outer cover plate and the inner cover plate, when the hatch cover module is laterally moved and slides to open the hatch, only the outer cover plate needs to slide away from the hatch, and the wing cover plates are arranged on the hatch cover module. The side moving sliding distance of the hatch cover is shorter, the needed side moving sliding rail length is shorter, at the moment, the inner cover plate is turned over by the wing cover plate, limitation of the inner cover plate is relieved, then the inner cover plate is turned over and stacked on the inner wall of the hatch through the rotating shaft, opening of the hatch is achieved, and compared with a traditional side moving type hatch cover, deck space needed by side moving of the hatch cover module is effectively reduced; and therefore, a larger hatch is formed in the bulk cargo ship, the bulk cargo ship can be conveniently matched with more efficient loading and unloading equipment, and the loading and unloading efficiency is effectively improved.

This invention belongs to the field of marine technology and discloses a hatch cover system and a cargo ship. The hatch cover system includes a hatch cover body rotatably mounted on the deck of the cargo ship, capable of rotating relative to the deck to switch between a covered state, a side enclosure state, and a deck extension state. In the covered state, the hatch cover body covers the upper part of the deck, thus covering the hatch opening of the cargo hold located below the deck. In the side enclosure state, the hatch cover body rotates to an angle with the deck, at which point it forms a side enclosure structure on the deck. In the deck extension state, the hatch cover body rotates to the outside of the cargo ship, at which point it can carry cargo. This hatch cover system can switch between multiple forms to function as a cover, a wall, and an extended deck area, improving functional integration and space utilization.

The utility model relates to ship hatch cover technical field, specifically disclose a detachable ship hatch cover, including hatch cover body, the hatch cover body is by the rectangular frame body of periphery and the inside detachable splicing subassembly constitute, the splicing subassembly includes a plurality of splicing blocks in the frame body is established, a plurality of splicing blocks are detachably connected through connecting component, and a plurality of splicing blocks jointly cover the internal area of frame body, through the second connecting piece and fix two splicing blocks of splicing adjacent, again by fixed bolt through third connecting piece to four adjacent splicing block's corner department meeting place upper surface fixed, by analogy, until the installation of whole hatch cover body is completed, and then through the hatch cover body design is detachable multiple splicing blocks, when maintaining and replacing, only need to dismount corresponding splicing block, do not need to hoist whole hatch cover body, has saved manpower, material resources and time, has reduced the operation difficulty.

The embodiment of the invention provides a hatch cover determination method and device applied to a ship, equipment, a medium and a product, and the method comprises the steps: obtaining the index data of a cabin body under at least two detection indexes for the cabin body of each cabin body type; the cabin type is determined according to the cabin information; according to the cabin body type, obtaining cabin cover geometric data of at least one to-be-selected cabin cover from a cabin cover provider; and for the same cabin body type, through the index data, the cabin cover geometric data and a preset error range threshold, determining the adaptation attribute of the to-be-selected cabin cover and the cabin body. According to the technical scheme provided by the embodiment of the invention, for the same cabin body type, through the index data, the cabin cover geometric data and the preset error range threshold value, the adaptation attribute of the cabin cover and the cabin body is quickly determined, and the manual comparison and trial assembly times are reduced, so that the effects of improving the cabin cover installation success rate, the installation reliability and the installation efficiency are achieved.

The invention relates to a cargo ship anti-instability hatch structure and a using method thereof.The cargo ship anti-instability hatch structure comprises a deck and a cover plate, a circular hatch is formed in the deck, the cover plate is in an inverted cone frustum shape, and a coaming matched with the side face of the cover plate in shape is arranged on the inner edge of the deck hatch; a supporting plate extending towards the center of the hatch is fixedly arranged at the bottom of the coaming, the diameter of the hatch is larger than that of the upper surface of the cover plate, when the cover plate covers the hatch, the hatch is attached to the cover plate along the transverse side of the cargo ship, and the cover plate, the anti-instability supporting part and the supporting plate on the side are locked through a locking mechanism. A gap is reserved between the other side of the hatch in the transverse direction of the cargo ship and the cover plate. The diameter of the cover plate is set to be smaller than that of the hatch, the gap is reserved between the side, in the transverse direction of the cargo ship, of the hatch and the cover plate during covering, space is reserved for deck deformation, the cover plate can still cover the hatch when the deck deforms, and the hatch structure is effectively prevented from being unstable under the action of external force.

The invention relates to the technical field of ship equipment, in particular to a bilateral opening hatch cover system and a ship. The hatch cover system comprises a hatch body, a hatch cover plate and a driving structure. The hatch body comprises a port part, a middle part and a starboard part which are sequentially connected in the ship width direction. Rollers are arranged on the hatch cover plate, and the hatch cover plate is slidably connected to the hatch body through the rollers. The driving structure comprises a port driving part arranged on the left side of the hatch cover plate and a starboard driving part arranged on the right side of the hatch cover plate, the output end of the port driving part and the output end of the starboard driving part are connected with gear assemblies correspondingly, and the hatch cover plate is connected with a rack extending in the horizontal direction. The larboard driving piece and the starboard driving piece are in meshing transmission with the rack through corresponding gear assemblies, and the driving structure is used for driving the hatch cover plate to slide from the middle part to the larboard part or the starboard part. Therefore, the hatch cover plate slides from the middle part to the port part or the starboard part, and the requirement that an ore carrier passes through the two sides of the barge on the anchored ground and leans against the barge to load and unload cargos is met.

The present application provides a simple shelter for flood refuge, which is lightweight, easy to carry, compact when stored, and low cost. The simple shelter for flood refuge has a substantially cylindrical floating body (10) configured by stacking a plurality of floats (10a-10d) in the vertical direction and connecting adjacent floats in the vertical direction to each other, and two partition plates (20, 20) respectively provided on the inner circumferential side of the uppermost and lowermost floats (10a, 10d) among the plurality of floats (10a-10d), a closed accommodation space (SP) for preventing water from the outside from entering and accommodating refugees is formed by the inner circumferential surface of the floating body (10) and the two partition plates (20, 20), and doors (24) for the refugees to enter and exit the accommodation space (SP) are respectively provided on the two partition plates (20, 20).

This application is directed to systems and methods of locking and unlocking a hatch lid or any other type of opening having a hinged covering. In some embodiments, a blade is actuated by a motor or linear actuator. Blades of the inventive subject matter can include one or two racks that interact with one or two pinion gears. In embodiments having rotational motors, a pinion gear can be coupled with that motor and with a rack that can cause the blade to move when the motor turns. In embodiments having linear actuators, the linear actuator more directly causes the blade to move. Other embodiments of the inventive subject matter include a screw mechanism that can interact with a locker receptacle upon rotating a motor coupled thereto.

The application discloses a side-moving type hatch cover oil motor portable dismounting device, which comprises an oil motor supporting device and an oil motor base, the oil motor supporting device is installed on a hatch coaming, the oil motor base is provided with an oil motor body, the oil motor supporting device is used for supporting the oil motor base after moving out, the oil motor body is used for driving a cargo hatch cover, a plurality of groups of second lifting lugs are fixedly arranged on the reverse surface of the oil motor base, the second lifting lugs are used for lowering the oil motor body to a main deck position, and the oil motor supporting device is fixedly connected with the hatch coaming through a plurality of groups of split pins. The technical key points are as follows: the device has low manufacturing cost, is portable and does not occupy space on the ship, is convenient to operate, effectively solves the problem that the hydraulic motor cannot be hoisted in the case that there is no large crane on the ship, replaces the traditional scheme of calling a large shore-based crane, realizes self-dynamic transfer of the oil motor, guarantees maintenance efficiency, and saves the cost of renting a large crane.

The utility model discloses a marine engine transport ship, which relates to the technical field of shipbuilding industry and comprises a ship body and a hatch cover, the ship body comprises a head section, a cargo compartment section and a tail section which are integrally connected in sequence, and the cargo compartment section is provided with an engine placing cavity with a top opening. The engine containing cavity is higher than a marine engine needing to be transported, and the hatch cover is used for being in rigid sealing connection with the top of the cargo hold section so as to open or seal a top opening of the engine containing cavity. The rear enclosure bulkhead comprises a fixed enclosure bulkhead and a movable enclosure bulkhead, the bottom of the movable enclosure bulkhead is hinged to the top of the fixed enclosure bulkhead, and the movable enclosure bulkhead can be overturned to the horizontal position in the direction away from the engine containing cavity and can be overturned to make contact with the fixed enclosure bulkhead, the left enclosure bulkhead, the right enclosure bulkhead and the hatch cover and be in sealed connection with the fixed enclosure bulkhead, the left enclosure bulkhead and the right enclosure bulkhead; weather tight closing of the warehouse can be achieved, the engine transportation requirement is met, loading and unloading are convenient, and the hoisting requirement of a shipyard is effectively met.

The present invention relates to the field of ship composite material structure and forming technology, and provides an ultra-large span all-composite material hatch cover and its preparation method, wherein the hatch cover comprises a lower panel, an intermediate layer, an upper panel and an external connection structure; the lower panel is bonded to the upper panel through the intermediate layer to form a hatch cover body, and both ends of the hatch cover body are respectively connected to the external connection structure, and are quickly and conveniently connected to the external structure by combining the main beam and the lattice structure, playing the role of force transmission support. The preparation method of the hatch cover comprises: step one, forming the lower panel; step two, preparing the intermediate layer; step three, laying the upper panel; step four, connecting the main beam to the external structure; pouring according to the vacuum integrated forming process to obtain the desired hatch cover; the present invention can achieve a span of not less than 5 meters, and the deformation under deadweight conditions is less than 2 mm. The hatch cover has the characteristics of light weight, high strength, high rigidity, designable lattice structure, low manufacturing cost, high forming rate, and low process risk.

The present application discloses a side loading system, including a cargo hold opening and closing assembly and a telescopic load-bearing assembly. The telescopic load-bearing assembly includes a transverse frame located at a corresponding position on the cabin top, a power unit for driving the transverse frame, and a load-bearing unit fixedly arranged on the transverse frame. In an embodiment of the present application, the above-mentioned side loading system is adopted. The porthole has two working modes when opened: upper opening and lower opening. In the lower opening state, the porthole can be used as a temporary loading platform for cargo. In the upper opening state, an open water space can be provided at the side plate for floating cargo. When the transversely movable transverse frame drives the load-bearing unit to move to the corresponding position of the cargo, the cargo can be hoisted by a steel wire rope, and the lifting and translation operations of the cargo can be realized by the cooperation of the transverse frame and the electric winch assembly. Compared with the side-swing and elevator loading and unloading systems, it has the characteristics of simple structure, high reliability and applicability.

The utility model relates to a bulk carrier electric hatch cover with high sealing performance, which is applied to the field of ships and comprises a cover plate positioned above a hatch of a cabin, a mounting plate fixedly connected to the lower end of the hatch of the cabin, a support frame slidably sleeved on the outer surface of the hatch of the cabin, two first cylinders fixedly connected between the support frame and the mounting plate, and two second cylinders fixedly connected between the support frame and the mounting plate. The left end and the right end of the cover plate are fixedly connected with top plates, the upper end of the supporting frame is fixedly connected with two top rods corresponding to the two top plates respectively, before the cover plate is rotated to be opened and closed, the cover plate can be moved upwards firstly, so that a gap is formed between the cover plate and a cabin opening, and then the cover plate is rotated to be opened and closed. When the hatch cover is closed, the sealing ring below the cover plate is difficult to rub with the hatch of the cabin, so that deformation caused by extrusion friction between the edge of the sealing ring and the hatch of the cabin is effectively avoided, and when the hatch cover is closed, the cover plate is pressed by the pressing assembly, so that the sealing performance of the hatch cover is improved.

The utility model discloses a rotary oil tank cover for a ship. The rotary oil tank cover comprises a hatch seat, a cover body, a bent supporting rod and a rotary disc, an extension table is fixed to the outer side wall of the hatch seat, a vertical pipe is fixed to the extension table, the hatch seat is covered with the cover body, a lead screw is fixed to the circle center of the outer end face of the cover body, a plurality of vertical grooves are formed in the side face of the lead screw, one end of the bent supporting rod is inserted into the vertical pipe, and the other end of the bent supporting rod is inserted into the vertical pipe. A first lantern ring and a second lantern ring are fixed to the other end of the bent supporting rod, the second lantern ring and the first lantern ring are mutually fixed in the mode that the central axes coincide, a plurality of clamping strips are arranged on the inner side wall of the second lantern ring, a plurality of connecting rods are fixed to the inner side of the rotating disc, and a nut base is fixed to the connecting position of the connecting rods; a thread is formed in the nut seat; the nut base is connected into the first lantern ring in a rotating fit mode, and the lead screw penetrates through the second lantern ring and the nut base and can assist the oil tank cover to be opened and closed in a labor-saving mode.

The present invention patent relates to an accessory for shiploaders for protection against rain. This device is applied in the field of marine and port logistics operations and more specifically concerns a covering accessory for rain protection and dust isolation during the loading of moisture-sensitive bulk products onto bulk carriers, and polluting products onto cargo ships. The accessory offers the advantages of being fixed to the shiploader and simple to operate, and having a compact and lightweight structure. The rotary covering accessory (ACR) is provided with a cage (3), a central structure (6), and beam assemblies (4-a). Alternatively, the covering accessory (AC) comprises a flange (11), a sealing duct (10), and arch assemblies (1-a) and (1-b).

A methods and systems of fumigating a vessel include delivering fumigant to a cargo area of the vessel. In particular, the vessel may be a roll-on / roll-off vessel. In such a system, an air pressure system is provided for maintaining a selected minimum pressure differential between a selected area of the vessel above the cargo area and the cargo area, such that pressure of the selected area is greater than the cargo area. A control system may maintain the pressure differential.

The portable hanging base for the hatch cover comprises a supporting bottom plate, one side plate body of the supporting bottom plate is attached to the top end of a hatch coaming, the other side plate body of the supporting bottom plate extends out of the edge of the hatch coaming in an overhanging mode, and the part, corresponding to a hatch inside the hatch coaming, of the plate body of the supporting bottom plate is provided with a hollow first avoiding part; bolt holes are formed in the positions, corresponding to the hatch coaming fixing studs, of the plate body; the fixed cylinder is vertically fixed on the overhanging section plate body of the supporting bottom plate, and the top of the cylinder body of the fixed cylinder is provided with an opening; a bottom stand column of the portable crane is arranged in the fixing cylinder in a penetrating mode and fixedly connected with the fixing cylinder through a limiting assembly. The portable crane base is simple in structure and convenient to disassemble, the portable crane base is installed and fixed through existing fixing studs of the hatch coaming, under the condition that stable rooting of the base is guaranteed, too much extra space is not occupied, repeated turnover use of a plurality of hatches can be achieved in a disassembling and installing mode, compared with a traditional base, the ship space is saved, and the cost is reduced. And the construction cost is reduced.

The application discloses a super-large square mud door installation structure and a drag suction dredger and a use method thereof, and belongs to the technical field of mud doors. The super-large square mud door installation structure comprises a mounting frame arranged on a main deck on the top of a mud tank, and further comprises a mud door oil cylinder, a sleeve, a supporting piece, a pushing piece and a positioning pin mechanism. The mud door oil cylinder is fixedly arranged on the mounting frame. The top of the sleeve is connected with the mounting frame, and the bottom of the sleeve extends into the mud tank through the main deck. The supporting piece is fixedly arranged on the inclined bottom plate of the mud tank, and the end, away from the inner wall of the mud tank, of the supporting piece is connected with the bottom of the sleeve. The pushing piece is slidably arranged in the sleeve, and the top of the pushing piece is connected with the piston rod of the mud door oil cylinder. The bottom of the pushing piece is movably connected with the mud door body which is hingedly connected with the bottom of the mud tank. The positioning pin mechanism is arranged on the mud door body. The mud door opening and closing and the positioning lock decoupling are simultaneously completed through a single stroke of the oil cylinder. The limitation that a traditional system needs independent oil paths / electric controls is broken, and the mechanical intelligentization of the ship heavy mechanism is realized.