Ventilation Structure of Cargo Hold in Cargo Ship

Abstract

Provided is a ventilation structure for a cargo hold of a cargo ship, which can increase the opening of a hatch and is such that a ventilation facility is less likely to be damaged during cargo handling. 【Solution means】In a cargo ship including a corrugated bulkhead 40 having a corrugated cross-sectional shape with unevenness for partitioning between two cargo holds CH, and winding type hatch covers 7A and 7B for opening and closing hatch coamings respectively provided at the upper part of each cargo hold, a mechanical blower 50 is installed on the coaming intermediate upper deck 3A in the space between the hatch coaming 20 and the other hatch coaming 30, and the height of the mechanical blower 50 is made lower than the heights of the hatch coamings 20 and 30. Since the mechanical blower 50 is installed using the dead space of the upper deck, the opening area of the hatch can be increased. Further, since the height of the mechanical blower 50 is lower than the heights of the hatch coamings 20 and 30, accidents such as contact with the cargo and breakage during cargo handling can be prevented.

Description

Technical Field

[0001] The present invention relates to a ventilation structure for a cargo hold in a cargo ship. More specifically, the present invention relates to a ventilation structure for a cargo hold in a cargo ship that transports bulk cargo such as limestone.

Background Art

[0002] In a cargo ship, a ventilation structure consisting of a ventilator for sending air into the cargo hold and an exhaust pipe for exhausting air is installed to ventilate the inside of the cargo hold so as not to cause condensation on the loaded cargo such as limestone or coal.

[0003] As a prior art of such a ventilation structure for a cargo hold, there is Patent Document 1. In this prior art, a ventilation pipe with a fan, a heater, and a dehumidifier built into the housing and an exhaust pipe with a fan built into the housing are installed on the upper deck beside the hatch coaming. The air sent into the cargo hold from the ventilation pipe passes through the cargo hold and exits from the exhaust pipe. Therefore, problems such as drying the inside of the cargo hold and preventing condensation from occurring on the loaded cargo have been prevented.

[0004] However, since the ventilation pipe and the exhaust pipe were installed beside the hatch coaming on the upper deck, they occupied a considerably large space on the upper deck and restricted the enlargement of the opening area of the hatch. When the opening of the hatch becomes narrow, the cargo handling efficiency decreases. In addition, since the heights of the ventilation pipe and the exhaust pipe are higher than the height of the hatch coaming, they interfere with the loading and unloading of cargo in the cargo hold using a crane or the like, and there has been a problem of damaging the ventilation pipe or the exhaust pipe.

Prior Art Documents

Patent Documents

[0005]

Patent Document 1

Summary of the Invention

Problems to be Solved by the Invention

[0006] In view of the above circumstances, an object of the present invention is to provide a ventilation structure for a cargo hold of a cargo ship that can increase the opening of the hatch and is less likely to be damaged during the loading and unloading of cargo by the ventilation equipment.

Means for Solving the Problems

[0007] The ventilation structure of a cargo hold in a cargo ship according to a first invention includes two adjacent cargo holds, a corrugated bulkhead having a corrugated cross-sectional shape with concavities and convexities for partitioning between the two cargo holds, a hatch coaming provided at the upper part of each cargo hold, and a winding type hatch cover for opening and closing the hatch coaming. In the cargo ship, a mechanical blower is installed on the upper surface of the upper deck in the space between the hatch coaming of one cargo hold and the hatch coaming of the other cargo hold, and the height of the mechanical blower is lower than the height of the hatch coaming. The ventilation structure of a cargo hold in a cargo ship according to a second invention is characterized in that, in the first invention, the mechanical blower is arranged such that the discharge port on its lower surface faces the recess of the corrugated bulkhead. The ventilation structure of a cargo hold in a cargo ship according to a third invention is characterized in that, in the first invention, in each cargo hold, an exhaust tower for discharging the air in the cargo hold to the outside of the ship is provided on the upper deck in the vicinity of the corrugated bulkhead facing the corrugated bulkhead on the side where the mechanical blower is installed.

Effects of the Invention

[0008] According to the first invention, It has the following effects. a) In a cargo ship having a structure in which a winding type hatch cover is provided on the hatch coamings of adjacent cargo holds, a space is generated between the adjacent hatch coamings, so a mechanical blower can be installed on the upper deck of that space. By using the dead space on the upper deck in this way, the opening area of the hatch can be increased. b) Since the height of the mechanical blower is lower than the height of the hatch coaming, accidents such as contact with the grab bucket of the loading and unloading crane and damage during the loading and unloading of cargo can be prevented. c)Since the outlet of the mechanical blower faces the recess of the corrugated partition, the vertically extending recess of the corrugated partition serves as a ventilation duct that draws air into the cargo hold. Therefore, external air can be efficiently sent into the interior of the cargo hold without using a ventilation duct. No. 2 According to the invention , ship Since the air sent into the hold is discharged from the exhaust tower, the air moves in the cargo hold and the air in the cargo hold can be ventilated. Moreover, there is no need to provide an extra dedicated exhaust space.

Brief Description of the Drawings

[0009]

Figure 1

Figure 2

Figure 3

Figure 4

Figure 5

Figure 6

Figure 7

Figure 8

Embodiments for Carrying Out the Invention

[0010] Next, embodiments of the present invention will be described based on the drawings. First, based on FIGS. 7 and 8, the schematic structure of the cargo ship S to which the present invention is applied will be described. The cargo ship S to which the present invention is applied has a structure in which a plurality of cargo holds are provided under the upper deck 3 between the bow 1 and the stern 2, and a bridge 4 is provided at the stern. The cargo holds in the illustrated cargo ship S include a first cargo hold CH1, a second cargo hold CH2, a third cargo hold CH3, and a fourth cargo hold CH4. However, the present invention includes those with 3 or fewer cargo holds and those with 5 or more cargo holds.

[0011] In the ceiling part (i.e., the upper deck 3) of each of the first cargo hold CH1 to the fourth cargo hold CH4, hatches, which are openings for loading and unloading cargo, are formed, and hatch coamings that constitute the edges of the openings are erected at each hatch. On the upper surface of each hatch coaming, a hatch cover, which is a lid for opening and closing the hatch, is disposed.

[0012] A retractable hatch cover is used for the cargo ship S of the present invention, and the retractable hatch cover includes a winch 71 and a cover body 72 that can be stored and extended by winding and unwinding around the winch 71. In the illustrated cargo ship S, two hatch covers 7A and 7B are used. For the hatch cover 7A, the winch 71 is installed on the upper deck 3 on the bow side, and the cover body 72 has a length that covers the hatches of the first cargo hold CH1 and the second cargo hold CH2. In the state where the cover body 72 is extended, it covers the hatches of the first cargo hold CH1 and the second cargo hold CH2, and the end of the cover body 72 reaches the end of the hatch near the center of the hull of the second cargo hold CH2. When the entire cover body 72 is wound up by the winch 71, the hatches of the first cargo hold CH1 and the second cargo hold CH2 open.

[0013] For the hatch cover 7B, the winch 71 is installed on the upper deck 3 near the bridge 4 at the stern, and the cover body 72 has a length that covers the hatches of the third cargo hold CH3 and the fourth cargo hold CH4. In the state where the cover body 72 is extended, it covers the hatches of the third cargo hold CH3 and the fourth cargo hold CH4, and the end of the cover body 72 reaches the end of the hatch near the center of the hull of the fourth cargo hold CH4. When the entire cover body 72 is wound up by the winch 71, the hatches of the third cargo hold CH3 and the fourth cargo hold CH4 open.

[0014] When using the above-described retractable hatch covers 7A and 7B, the occupied space on the upper deck 3 can be significantly reduced when the hatch covers are retracted and stored, as compared to single-pull type or folding type hatch covers. In particular, since there is no need to install devices for opening and closing the hatch on both sides of the hatch, the opening area of the hatch in each cargo hold can be increased. For each hatch of the cargo holds CH1, CH2, CH3, and CH4, a hatch coaming is erected on the upper deck 3. However, there is a space without a hatch coaming between the cargo holds CH2 and CH3. Note that the hatch coamings are connected between the cargo holds CH1 and CH2, and between the cargo holds CH3 and CH4. In the ventilation structure of the present invention, the space 3S between the hatch of the second cargo hold CH2 and the hatch of the third cargo hold CH3 is utilized. For the first cargo hold CH1 and the fourth cargo hold CH4, a conventionally known ventilation structure or any other arbitrary ventilation structure is applied.

[0015] Based on FIGS. 1 to 5, a ventilation structure according to an embodiment of the present invention will be described. FIG. 1 is an enlarged view of a portion I shown in FIG. 7, and FIG. 2 is an enlarged view of a portion II shown in FIG. 8. In FIGS. 1 and 2, the hatch coaming of the second cargo hold CH2 is denoted by reference numeral 20, and the hatch coaming of the third cargo hold CH3 is denoted by reference numeral 30. Also, the vertical walls of the hatch coamings 20 and 30 are denoted by reference numerals 21 and 31, respectively.

[0016] In FIGS. 1 and 3, 11 is the outer bottom plate of the ship, 12 is the inner bottom plate, and 13 is the outer side plate of the ship. The inner bottom plate 12 also serves as the bottom plate of each of the cargo holds CH1 to CH4. As previously described with reference to FIG. 7, and as clearly shown in FIGS. 1 and 2, there is a space 3S where no hatch is formed between the vertical wall 21 of the hatch coaming 20 and the vertical wall 31 of the hatch coaming 30. The bottom of this space 3S is connected to the upper deck 3 throughout the hull. The upper deck of this space portion (hereinafter sometimes referred to as the upper deck between coamings) is labeled with reference numeral 3A to distinguish it from the upper deck 3 of other portions.

[0017] As shown in FIGS. 1 to 3, below the poop deck 3A, a corrugated bulkhead 40 serving as a bulkhead between the holds is installed, separating the second hold CH2 and the third hold CH3. This corrugated bulkhead (also referred to as a corrugated bulkhead) 40 has a corrugated cross-sectional shape and has a shape in which recesses 41 and protrusions 42 are alternately continuous in plan view. The corrugated bulkhead is characterized by higher strength compared to a flat bulkhead (also referred to as a plain bulkhead) forming a plane. Note that between the first hold CH1 and the second hold CH2, and between the third hold CH3 and the fourth hold CH4, they are also partitioned by bulkheads, and any bulkheads such as corrugated bulkheads or flat bulkheads can be used for those bulkheads.

[0018] As shown in FIGS. 1 and 4, below the lower part of the corrugated bulkhead 40, a lower stool 45, which is an obliquely inclined flat plate, is provided between the inner bottom plate 12 of the ship's bottom. In addition, in each recess of the corrugated bulkhead 40, a slant plate 43 is attached to facilitate the downward flow of general cargo.

[0019] As shown in FIGS. 1 to 4, a mechanical blower 50 is installed on the poop deck 3A. This mechanical blower 50 is a blower provided with a fan inside, and can suck air from above and blow it downward by the rotation of the fan. The mechanical blower 50 shown in FIG. 4 includes a fan 53 rotated by an electric motor 52 etc. in a housing 51, a damper 54 is provided in the upper part of the housing 51, and a discharge port 55 is formed in the lower part of the housing 51. Note that not limited to the above structure, a known mechanical blower or a blower with other structures can be adopted.

[0020] As shown in FIG. 4, since the discharge port on the lower surface of the mechanical blower 50 faces the recess of the corrugated bulkhead 40, the recess extending vertically in the corrugated bulkhead 40 serves as a ventilation duct for drawing air into the hold. Therefore, it is not necessary to use a dedicated ventilation duct, and the necessary hull structural members can be reduced.

[0021] As shown in Fig. 8, in each cargo hold, an exhaust tower 60 for discharging the air in the cargo hold to the outside of the ship is provided in the vicinity of the corrugated bulkhead 40 facing the corrugated bulkhead 40 on the side where the mechanical blower 50 is installed. The location where the exhaust tower 60 is provided is on the upper deck 3 beside the hatch. In the illustrated cargo ship S, since the port side is used for cargo handling using a quay crane or the like, the exhaust tower 60 is provided on the upper deck 3 on the starboard side. However, in the case of a cargo ship that performs cargo handling on the starboard side, the exhaust tower 60 may be provided on the upper deck 3 on the port side.

[0022] As shown in Fig. 5, the exhaust tower 60 is a box-shaped structure with an exhaust port 62 formed in the housing 61. The housing 61 of the exhaust tower 60 and the inside of the cargo hold CH are connected by an exhaust passage 64 formed in the pipe space 63. The exhaust passage 64 is a cavity formed by using the upper space part of the pipe space 63, and an opening 67 leading to the cargo hold CH is formed. Therefore, the air in the cargo hold CH can be induced as shown by the arrow and exhausted to the outside of the ship.

[0023] The bottom wall 66 of the exhaust passage 64 is inclined toward the inside of the cargo hold CH, and the inclination angle θ is set to be larger than the angle of repose of bulk cargo, for example, limestone. Therefore, even if the limestone tower in the cargo hold CH is sucked into the exhaust passage 64, it will fall back into the cargo hold CH again and will not be discharged to the outside of the ship. Since various pipes 68 passing through the ship are collectively arranged in the pipe space 63, by forming the exhaust passage 64 in this part, it is not necessary to provide an extra dedicated exhaust space.

[0024] The housing 61 of the exhaust tower 60 is installed on the upper deck 3 beside the hatch (transverse in the width direction of the hull), and it is preferable to install a wave-breaking plate in front of it (in the forward direction in the longitudinal direction of the hull). By doing so, seawater will not enter the cargo hold CH during navigation.

[0025] As shown in FIGS. 6A and 6B, the air sent into the cargo hold by the mechanical blower 50 is discharged outside the ship from the exhaust tower 60 as indicated by the white arrows, so that the air moves sufficiently in the cargo hold CH without stagnating. Therefore, the air in the cargo hold CH can be sufficiently ventilated, and inconveniences such as condensation on the cargo in the cargo hold do not occur.

[0026] As described above based on FIG. 1, the mechanical blower 50 is installed on the upper deck 3A of the coaming space 3S between the hatches 20 and 30 in the adjacent cargo holds CH2 and CH3. If the cargo ship S is in navigation, the hatch is covered with the hatch cover 72, but the space above the space 3S is open without being covered. Therefore, the mechanical blower 50 can suck in air without hindrance and send it into the cargo hold CH.

[0027] With this ventilation structure, the dead space of the upper deck 3 is utilized, so that a wide space of the cargo hold CH can be secured. Furthermore, since the height of the mechanical blower 50 is lower than the height of the hatches 20 and 30, accidents such as damage caused by contact between the grab bucket of the cargo handling crane and the cargo during cargo handling can be prevented.

Explanation of Signs

[0028] 1 Bow 2 Stern 3 Upper deck 4 Bridge 7A Hatch cover 7B Hatch cover 20 Hatch coaming of the second cargo hold CH2 30 Hatch coaming of the third cargo hold CH3 40 Corrugated bulkhead 41 Recess 42 Projection 43 Slant plate 45 Lower tool 50 Mechanical blower 51 Housing 52 Electric motor 53 Fan 60 Exhaust tower 61 Housing 62 Exhaust port 63 Pipe space

Claims

1. A cargo ship having two adjacent holds, a corrugated bulkhead having a corrugated cross-sectional shape for separating the two holds, hatch coamings provided at the top of each hold, and a roll-up hatch cover for opening and closing the hatch coamings, A mechanical fan is installed on the upper surface of the upper deck in the space between the hatch coaming of one hold and the hatch coaming of the other hold, The mechanical blower is disposed so that a discharge port on a lower surface thereof faces the recess of the corrugated partition wall, The height of the mechanical blower is lower than the height of the hatch coaming. A ventilation structure for a cargo hold in a cargo ship.

2. An exhaust tower is provided on the upper deck next to the hatch coaming provided at the top of each of the holds, The exhaust tower and the hold are connected by an exhaust passage provided in the space above the pipe space, which is a section in which various pipes that run through the ship are arranged.

2. The ventilation structure for a cargo hold in a cargo ship according to claim 1.

Images