GB2418177A - Inflatable means for securing cargo - Google Patents

Abstract

Cargo is secured in a cargo container, such as the hold of a ship by placing dunnage bags between the cargo items. Each dunnage bag 3 is connected to a manifold 7 by an individual bag hose 8 and the manifold is connected to a source of compressed air. The manifold 7 supplies compressed air to each bag 3 so that a substantially constant pressure is maintained in each bag. A method of automatically monitoring the pressure in each bag over a period of time and, if the pressure drops, automatically introducing air to the bags, is also disclosed.

Description

-1- 2418177 Securing Cargo This invention relates to the securing of cargo

in cargo containers. In most cases, the container will be a cargo hold of a ship, but the invention may find application in, for example, shipping containers or goods lorries.

Dunnage bags are air-filled cushions placed between cargo items to be secured, and between cargo items and walls of the cargo space.

Dunnage bags tend to lose pressure when used for long journeys, such as during a typical ocean voyage. The bags may experience small air leaks through their membrane, valves and seams. These leakages, together with variations in . :., ambient temperature and atmospheric pressure, combine to reduce the cargo l;;st securing capacity of the bags.

As the bags lose pressure, the cargo becomes loose in the hold. If the cargo is 1888.

2 not held securely, it may be damaged during pitching, rolling and yawing of the :::! vessel. If the cargo is able to move in the hold, small gaps which do not contain ' t dunnage bags are able to close up and larger gaps which do contain dunnage i0 bags get bigger. As the larger gaps widen, the dunnage bags are unable to exert .

sufficient force on the cargo unless they are topped up with air.

Currently, dunnage bags must be topped up manually, for example by deck hands.

: . . The dunnage bags require constant monitoring to determine which bags require topping up or even replacing if they burst. The procedure is often impractical as it ..

may be difficult to gain entry to the cargo hold or unsafe to perform such a.

e procedures during times of rough weather. If the dunnage bags burst or leak and : : are not replaced or topped up, the cargo may become damaged during the Journey. ...

According to the invention there is provided apparatus for securing cargo in a walled cargo container, the apparatus comprising a manifold adapted to be P4508.A2(1) 19 September 2005 connected to a source of compressed air, a plurality of dunnage bags, air hoses leading from the manifold to each of the bags, the manifold including means for admitting compressed air to each bag so that a substantially constant pressure is maintained in each bag.

The manifold may comprise a unit which can be placed inside the cargo container, the workings of the manifold being substantially located inside the unit, and the unit having an inlet for connection to a supply of compressed air, and a plurality of outlets for connecting to the plurality of dunnage bags. In use, hoses lead from each inlet to a dunnage bag.

Preferably the manifold includes an inlet and a plurality of outlets, the inlet being adapted for connection to a source of compressed air. The source of compressed I;;r air may be an air compressor unit located within the manifold, or external to the manifold. Alternatively, the manifold may be connected to the air supply line of a ship. Pressure regulating means may be located between the inlet and the source 1118t, of compressed air, to reduce the pressure of the air supplied to the manifold. -e 86.1

! ! Each dunnage bag may be connected to an outlet by an air hose. Preferably the air hoses have self-sealing couplings on each end for connection to the outlet and .

for connection to the dunnage bags. The manifold is designed to top-up dunnage bags with air if they lose pressure. The manifold preferably includes a top-up supply line coupled to the inlet, and pressure regulating means located between : . . the inlet and the top-up supply line for regulating the pressure in the top-up supply line to a predetermined inflation pressure. Preferably each outlet is coupled to the .e top-up supply line by a top-up conduit, wherein each top-up conduit includes .e restriction means for restricting air flow through said top-up conduit.

are-: The restriction means may be adjustable, such as a valve. Preferably, however, .

the restriction means is a fixed restrictor which restricts the rate of air flow through the top-up conduit to a predetermined rate characteristic of the restrictor and the predetermined inflation pressure. Using fixed restrictors is less costly than using P4508.A2(1) 19 September 2005 - 3 adjustable restrictors, and simplifies the construction and operation of the manifold.

Preferably the compressed air supplied to the manifold is at a pressure in the range 6 to 10 bar. Preferably, for ship-board use, the predetermined inflation pressure is in the range 0.2 to 1.0 bar, and more preferably in the range 0.4 to 0.6 bar. Preferably, the predetermined rate of air flow through each restrictor is substantially 5 litres per minute. This arrangement means that air leaks in the bags or the bag hoses of up to 5 litres per minute do not substantially affect the pressure of the other bags.

The top-up conduits may include non-retum valves to prevent air from escaping : from the bags back towards the air inlet of the manifold. Alternatively, a single I;;' non-return valve may be located in the top-up supply line to perform a similar function. Each dunnage bag may have a non-return valve integral to the air inlet of the bag. The top-up conduits may include isolation valves so that the air supply 1111.

to a bag may be completely shut off if the bag bursts or develops a major air leak. me-e.

The valve can be closed in the event of a major air leak in the dunnage bag or bag !.' conduit associated with said top-up conduit. This enables a leaking or burst dunnage bag to be isolated from the other bags such that the integrity of the . system is maintained and the remaining bags do not therefore lose pressure.

The manifold may also be adapted for rapidly filling the bags. Preferably the : . . manifold includes a fast-fill supply line coupled to the inlet, and to each outlet by a .

fast-fill conduit. A fast fill valve may be located between the inlet and the fast fill .e line to control the airflow through the manifold, such that the air can bypass the eves top-up conduits in order to fast fill the bags.

I

. The manifold may include pressure regulating means to prevent the bags from I. . 30 over inflating during fast-fill mode. This may be achieved by locating a pressure regulator between the inlet and fast-fill supply line for regulating the pressure in the fast-fill supply line to a predetermined fast-fill pressure. Preferably, the P4508.A2(1) 19 September 2005 - 4 predetermined fast-fill pressure is substantially 1 bar.

The fast-flu conduits may include non-return valves to prevent air from escaping from the bags back towards the air inlet of the manifold. Each fast-fill conduit may include an isolation valve. This enables a dunnage bag to be isolated from the rest of the system in the event of a major air leak such that the pressure in the remaining bags is substantially unaffected.

The manifold may further include pressure regulating means associated with each dunnage bag enabling the pressure in each bag to be independently controlled.

These pressure regulating means may be located within the manifold, or they may be external to the manifold and directly coupled to the air inlets of the dunnage * :.:. bags.

I *at I' .t The manifold may include a computer processing unit, such that the manifold is computer-controlled to automate the opening and closing of some or all of the individual valves, and control the pressure regulators. A. 1...1

!.' In an alternative arrangement the manifold may comprise one or more primary hoses suitable for connection to a source of compressed air and having a plurality of outlets along their length. In use, the primary hoses extend within the cargo container, and dunnage bags are connected to the outlets by secondary hoses.

The advantage of this system is that relatively short lengths of hosing are required.

Preferably the primary hoses are comprised of a number of hose sections which are connected together at junctions by junction units. The outlets are located at A. the junctions.

e..

. The junction units each preferably contain means for exposing the dunnage bags .e either to a flow of high pressure air or to a restricted flow of air, such that the bags can be rapidly filled to an approximate working pressure when exposed to the high pressure flow (fastfill mode), and substantially maintained at the working pressure P4508. A2(1) 19 September 2005

- -

when exposed to the restricted flow (top-up mode).

Each junction unit may comprise means for manually selecting the fastfill or top- up mode, such that each junction unit is manually and independently controllable by an operator. Alternatively or additionally, the junction units may be computer controlled, such that they are automatically switched from fast-fill mode to top-up mode when a predetermined inflation pressure is reached in the corresponding dunnage bag.

The junction units may include means for selectively restricting the flow of air introduced to the dunnage bags depending on the pressure of the introduced air.

: The invention also provides a method of securing cargo in a walled cargo i'.' container, the method comprising the steps of: 4e5 placing dunnage bags in spaces between cargo items; initially inflating the bags so that the bags occupy at least some of the spaces; and automatically monitoring " the pressure in each bag over a period of time and, if the pressure drops, :::! automatically introducing air to the bags. The method may also include the step of ! automatically expelling air from the bags if the pressure in the bags increases. me . I e e. . . e. . e e.

P4508.A2(1) 19 September 2005 - 6 The invention will now be further described, by way of example, with reference to the following drawings in which: Figure 1 shows prior art apparatus for securing cargo in a walled cargo container.

Figure 2 shows apparatus for securing cargo in accordance with the present invention.

Figure 3 is a schematic of a manifold system.

Figure 4 shows a section of the manifold having isolation valves for :.: . isolating individual dunnage bags. !;i"'

L5 Figure 5 shows a section of the manifold having pressure regulators for controlling thepressureofindividualdunnage bags. teea'

Figure 6 shows an alternative embodiment of the invention, in which the !. ! manifold comprises a primary hose having outlets for connecting dunnage bags to via secondary hoses. ë

Figure 1 shows the prior art apparatus for securing cargo in a walled cargo container. A walled cargo container is shown generally at 1. The container contains bales of cargo 2. The bales 2 are arranged such that there are either #

25 small gaps 5, or larger gaps 6 between adjacent bales. Dunnage bags 3, ca...DTD: indicated by the hatching on Figure 1, are placed in the larger gaps 6 and are *.

individually inflated by the crew 4. The inflated dunnage bags 3 exert a force on a' the cargo which presses the bales against one another and against the walls of the container thus securing the cargo in place in the container 1. The pressure in -. 30 the dunnage bags is monitored by the crew 4 during the transit. If the pressure in a bag falls too low to secure the cargo, the bag is topped up by a member of the crew 4.

P4508.A2(1) 19 September 2005 - 7 Figure 2 shows apparatus for securing cargo in a walled cargo container 1 according to the present invention. The apparatus comprises a manifold 7 connected to a source of compressed air, a plurality of dunnage bags 3 and bag conduits 8 leading from the manifold to each of the bags 3. In this case, the bag conduits 8 are standard bag hoses. The manifold 7 in this example is a single unit having the workings contained substantially therein.

The manifold 7 can operate in two modes: a fast fill mode, and a top-up mode. In fast fill mode, the manifold 7 simultaneously inflates each dunnage bag 3 up to a predetermined fast-fill pressure. Once the predetermined fast-fill pressure is reached, the manifold is switched to top-up mode. In top-up mode, the manifold :: . maintains a predetemmined inflation pressure of the bags 3 by automatically ), j' supplying air to individual bags 3 if they lose pressure.

A manifold 7 is shown in more detail in Figure 3. The manifold shown is suitable llll HI for rapidly filling and maintaining a pressure in a set of twenty dunnage bags. The A' manifold components are located inside an enclosure indicated by the dotted line I 9 1 - 0 The manifold 7 has an inlet 13 and twenty outlets 50. The inlet 13 is connected to a source of compressed air 10 as described in more detail below. Each outlet 50 is coupled to a dunnage bag by an air hose 8. The air hose 8 is connected to the : ,*, outlet 50 by a coupling 15, and to a dunnage bag by an adapter 18. Outlet 55 in Figure 3 is illustrated turned sideways so that the coupling 15 to bag hose 8 may be seen. as ea Acne

area The manifold 7 also has a top-up supply line 20 coupled to the inlet 13 by a top-up supply line conduit 53. The top-up supply line conduit 53 includes a pressure Alga * 30 regulator 25 for regulating the pressure in the top-up supply line 20 to a o.

predetermined inflation pressure. Each outlet 50 is coupled to the top-up supply line 20 by a top-up conduit 51. Each top-up conduit 51 includes a fixed restrictor P4508.A2(1) 9 September 2005 - 8 17 for restricting air flow through the top-up conduit 51.

The manifold 7 has a fast-fill supply line 21 coupled to the inlet 13 by a fast-fill supply line conduit 54, and to each outlet 50 by a fast-fill conduit 52. A non-retum valve 16 is located in each fast-fill conduit 52 to prevent air escaping from the bags back towards the fast-fill supply line 21. The fast-fill supply line conduit 54 includes a fast fill valve 19, having open and closed positions, to switch the manifold between fastfill and top-up modes. The fast-fill supply line conduit 54 also includes a pressure gauge 24 and a pressure regulator 23 to regulate the pressure in the fast-fill supply line to a predetermined fast-fill pressure. The pressure regulator 23 is protected by a filter 22.

*, The manifold 7 is connected to a supply of compressed air 10 via an inlet hose 11 !;i':. and connection 12. The manifold may be used on a ship, and connected to the ships air supply. Alternatively, the manifold may be connected to a separate air compressor. The pressure of the compressed air is typically in the range of 6 to life ' 10 bar. A filter 22 is located between the air supply 10 and the inlet hose 11 to le catch any liquid or particles from the air supply 10. Self sealing couplings 28 and ". t 29 are located at the ends of the inlet hose 11 to prevent air escaping at the | .8ee interface between the hose 11 and the manifold 7, and the hose and the filter 22.

The pressure regulator 25 which is located in the top-up supply line conduit 53 of the manifold 7 regulates the pressure during top-up mode. The pressure regulator is protected by a filter 30. The pressure in the top-up supply line 20 is indicated .,25 by a pressure gauge 26. A non-return valve 27 is located in the top- up supply line \ conduit 53 to prevent air from escaping out of the bags and back towards the . a! supply 10. ae.

In operation, the manifold 7 is connected to an air supply 10 and to twenty e i' 30 dunnage bags via twenty bag hoses 8. The dunnage bags are placed in spaces between individual bales of cargo and between the cargo and the walls of the cargo container. The pressure regulator 23 is set to a predetermined fast-fill P450B.A2(1) 19 September 2005 - 9 - pressure, and the pressure regulator 25 is set to a predetermined inflation pressure.

Air from air supply 10 enters the manifold through the inlet 13. Fast-fll valve 19 is initially set to an open position and the manifold 7 operates in fast-fill mode. In fast-fill mode, air passes from the inlet 13, through fast-fill supply line conduit 54, through the fast-fill supply line 21, through the fast-fill conduits 52, through the one-way valves 16, through bag conduits 8 and into the dunnage bags. Air flow continues until the pressure in the fast-fill supply line 21 reaches the predetermined fast-fill pressure.

When the predetermined fast-fill pressure is reached, the valve 19 is closed and the manifold 7 operates in top-up mode to substantially maintain an inflation 2 pressure in the bags. If a bag loses pressure, air flows from the inlet 13, through :iiF top-up supply line conduit 53, through top-up supply line 20, through top-up conduits 51, through restrictors 17, along air hose 8 and into the dunnage bag to : .' top-up the dunnage bag to the inflation pressure. i...'

: An alternative method involves fast-filling the bags to the approximate working pressure, and then switching the manifold to top-up mode to maintain the bags at the working pressure.

The restrictors 17 are selected to allow air to pass through at a predetermined rate. The manifold system is able to maintain the pressure in a bag having an air leak provided that the rate of air loss from the bag does not exceed the predetermined rate. Preferably the restrictors allow air to flow through at a rate of ^ . 5 litres per minute tl/min). With such restrictors, the manifold system can maintain the pressure in bags having air leaks of up to 5 I/min. e.

If the rate of air loss from a bag exceeds the predetermined rate, the relevant bag will gradually deflate. The integrity of the rest of the system will, however, be e.

substantially unaffected. The restrictors 17 effectively isolate the individual bags p4508.A2(1) 9 September 2005 - 10 such that major air leaks, or burst bags, only result in the system losing air at a rate not exceeding the predetermined rate, which is preferably 5 I/min. The foregoing also applies to leaks or splits in the hoses 8 or couplings 15. As the air supply 10 to the manifold can provide air at a rate far greater than 5 I/min, the pressure in the other bags is not affected.

Figure 4 shows a fast-fill conduit 52 having an isolation valve 31. Valve 31 can be closed if a major air leak occurs in the bag connected to the fast-fll conduit 52 during fast fill mode. The top-up conduit 51 also has an isolation valve 32 which can be closed to isolate the bag in the event of a major air leak during top-up mode. The valves may be controlled manually, or they may be computer controlled. , . 1.

i;is Figure 5 shows a top-up conduit 51 having a pressure regulator 33. With this s5 arrangement, the pressure in each bag may be independently controlled. A pressure gauge 34 is also shown. Each of the pressure regulators 23, 25 (Figure 3) and 33 (Figure 5) may be set manually, or may be computer controlled.

be,' hi a 4 lo An alternative embodiment of the invention is shown in Figure 6. In this ,2p embodiment, the manifold comprises primary hoses 60 which are connected to a supply of compressed air 62 through the walls of the container 1. The compressed air is passed through suitable water and particle filters fitted in an accessible position outside the container.

The primary hoses 60 are formed from a number of hose sections 64 which are connected together at junctions 66 by junction units (not shown). Each junction unit is enclosed in a casing 72 for mechanical protection. Dunnage bags 3 are connected to an outlet 68 of each junction unit via secondary hoses 70. e.

e..: The junction units are formed from standard pneumatic components, and each junction unit incorporates a connection for fast-filling and a connection for topping up the dunnage bags 3.

p4508.A2(1) 9 September 2005 - 11 The junction units (not shown) each comprise a tube having connector portions at each end for connecting adjacent hose sections 64 together. A channel extends from the tube and includes a connector portion for connecting to a secondary hose 70.

In one embodiment, the junction units each include a valve which is manually controlled via a lever. The lever can be moved between first and second positions. Moving the lever to the first position causes the valve to open and allow high pressure air to flow from the primary hose 60 along a fast-fill path within the junction unit and to the dunnage bag 3 via the secondary hose 70. The junction units may also include suitable means to prevent the dunnage bags 3 from over inflating. Moving the lever to the second position causes the valve to close and i;;' ' divert air along a top-up path within the junction unit and to the dunnage bag 3 via 615 the secondary hose 70. The top-up path contains a pressure regulator and a "lo. restriction to restrict the rate of air-flow to the dunnage bag 3. 1: .

] In another embodiment, the junction units are arranged to operate in top-up mode, via a pressure regulator, as a default. In this embodiment, a valve is included so . alp that the pressure regulator can be by-passed during fast-fill mode. The valve is . manually operated for example by a lever. To fast-fill the bags, the pressure regulator is bypassed by opening the valve using the lever. The fast-fill and top-up paths are coincident with one another downstream of the pressure regulator. An in-line pressure-relief valve having a small aperture therein is included downstream of the pressure regulator for controlling the flow during top-up mode.

During fast-fill, the high pressure air causes the in-line pressure relief valve to - open and allow an unrestricted flow of high pressure air to flow threrethrough.

A. When in top-up mode, the lower pressure air is unable to open the inline pressure relief valve, but a small volume flows through the internal hole and into the dunnage bag to maintain the bag at the working pressure. : ...

In other embodiments, the junction units may be computer controlled or p4508.A2(1) 19 September 2005 - 12 pneumatically controlled such that they are automatically switchable between top- up or fast-fill modes. When operated automatically, the junction units initially operate in fast-fill mode to rapidly inflate the bags. The pressure in each bag is automatically monitored, and once a predetermined pressure is reached in a particular bag, the corresponding junction unit automatically switches to operate in top-up mode to substantially maintain the bag at the working pressure.

It should be understood that the invention has been described above by way of example only, and that modifications in detail can be made without departing from the scope of the invention as defined by the claims. t.) A. . ë ..e ..e ë Ace. .e e e -e . ..

P4508.A2(1) 19 September 2005 - 13

Claims (26)

1. Apparatus for securing cargo in a walled cargo container, the apparatus comprising a manifold adapted to be connected to a source of compressed air, a plurality of dunnage bags, air hoses leading from the manifold to each of the bags, the manifold including means for admitting compressed air to each bag so that a substantially constant pressure is maintained in each bag.

2. Apparatus as claimed in Claim 1, wherein the manifold includes an inlet and a plurality of outlets, the inlet being adapted for connection to a source of compressed air, each dunnage bag being connected to an outlet by an air hose, the manifold further including a top-up supply line coupled to the inlet, pressure regulating means located between the inlet and the top-up supply line for i.' regulating the pressure in the top-up supply line to a predetermined inflation :6 pressure, each outlet being coupled to the top-up supply line by a top- up conduit, wherein each top-up conduit includes restriction means for restricting air flow " " through said top-up conduit.

1 te,11 Alit.!

3. Apparatus as claimed in Claim 2, wherein the restriction means is a fixed i", restrictor which restricts the rate of air flow through the top-up conduit to a predetermined rate characteristic of the restrictor and the predetermined inflation pressure.

4. Apparatus as claimed in Claim 2 or Claim 3, wherein each top-up conduit has an isolation valve.

5. Apparatus as claimed in any one of Claims 2 to 4, wherein the manifold further includes a fast-fill supply line coupled to the inlet, and to each outlet by a fast-fill conduit. .. t0

6. Apparatus as claimed in Claim 5, wherein a fast fill valve is located between : the inlet and the fast fill line. ë

P4508.A2(1) 19 September 2005 - 14

7. Apparatus as claimed in Claim 5 or Claim 6, wherein a pressure regulator is located between the inlet and fast-fill supply line to regulate the pressure in the fast-fill supply line to a predetermined fast-fill pressure.

8. Apparatus as claimed in Claim 7, wherein the fast fill pressure is substantially 1 bar.

9. Apparatus as claimed in any one of Claims 5 to 8, wherein each fastfir conduit has an isolation valve.

10. Apparatus as claimed in any one of Claims 2 to 9, wherein a pressure regulator is associated with each dunnage bag. t8 88

)6

11. Apparatus as claimed in any preceding claim, the apparatus further ttt8 including a computer processing unit and at least one computer controlled valve "" which can be actuated by said computer processing unit, the apparatus arranged I such that in use the control of said valve is automated. 38' a.

",

12. A method of securing cargo in a walled cargo container, the method . comprising the steps of: placing dunnage bags in spaces between cargo items; initially inflating the bags so that the bags occupy at least some of the spaces; and automatically monitoring the pressure in each bag over a period of time . :.: . and, if the pressure drops, automatically introducing air to the bags. ..

13. A method as claimed in Claim 12, wherein the step of initially inflating the bags is performed in a fast-fill mode in which the bags are rapidly inflated to a .e 30 pressure not exceeding a predetermined fast-fill pressure. : -e

.:

14. A method as claimed in Claim 12 or Claim 13, further including the step of P4508.A2(1) 19 September 2005 - 15 coupling each bag to a restricted air top-up conduit, such that air is supplied to each bag at a restricted rate to maintain a substantially constant pressure in the bags over an extended period of time.

15. A method as claimed in any one of Claims 12 to 14, further including the steps of detecting a dunnage bag having air leaking therefrom and, if the air is leaking at a rate below a predetermined rate, increasing the air supply to said dunnage bag or, if the air is leaking at a rate equal to or greater than said predetermined rate, closing an isolation valve to prevent air flow to said dunnage bag.

16. A method as claimed in Claim 15, wherein the isolation valve is computer controlled.

1.1' ' 16

17. A method as claimed in any one of Claims 12 to 16, further including the 6883 step of independently selecting the pressure of each dunnage bag by adjusting a " " pressure regulator associated with each bag. ...'

id!

18. A method as claimed in Claim 17, wherein the pressure regulator l associated with each bag is computer controlled.

19. Apparatus as claimed in Claim 1, wherein the manifold comprises one or more primary hoses, the primary hoses having a plurality of outlets along their length for connecting to the plurality of dunnage bags.

:: .

20. Apparatus as claimed in Claim 19, wherein the primary hoses are comprised . of a number of hose sections which are connected together at junctions by junction units, and wherein an outlet is located at each junction. A-.

21. Apparatus as claimed in Claim 20, wherein the junction units each contain means for exposing the dunnage bags to a flow of high pressure air or to a restricted flow of air, such that the bags can be rapidly filled to an approximate P4508.A2(1) 19 September 2005 - 16 working pressure when exposed to the high pressure flow, and substantially maintained at the working pressure when exposed to the restricted flow.

22. Apparatus as claimed in Claim 21, wherein each junction unit comprises means for manually selecting a fast-fill or a top-up mode.

23. Apparatus as claimed in any one of Claims 21 or Claim 22, wherein the junction units include means for selectively restricting the flow of air introduced to the dunnage bags depending on the pressure of the introduced air.

24. Apparatus as claimed in any one of claims 21 to 23, wherein the junction units are controlled to be automatically switchable between a fast-fill and a top-up mode. !.:':

1

25. Apparatus for securing cargo in a walled cargo container substantially as herein described with reference to or as shown in Figures 2 to 6 of the "" accompanying drawings. l"'i

t.'

26. A method of securing cargo in a walled cargo container substantially as ]0 herein described with reference to Figures 2 to 6 of the accompanying drawings. . . .. -e A. ...e . eve. ..

p4508.A2(1) 19 September 2005