Barge Securing Manual -

CARGO SECURING MANUAL

DUMB BARGE “BARGE NAME”

Prepared by:

1

IMPORTANT THESE GUIDANCE NOTES ONLY APPLY TO THE NAMED BARGE OPERATING WITHIN THE FOLLOWING TRADING AREAS:SINGAPORE COASTAL WATERS INCLUDING VOYAGES TO BATAM (FOR OTHER BARGES AND VOYAGES BEYOND THESE LIMITS FURTHER SECURING MEASURES WILL HAVE TO BE AGREED WITH THE CLUB).

THE MASTER OF THE TUG TOWING A BARGE IS RESPONSIBLE FOR THE BARGE AND THE CARGO THAT HE IS TOWING. HE MUST BE SATISFIED THAT THE STEVEDORE HAS PROPERLY LOADED AND SECURED THE CARGO BEFORE SAILING. IF HE IS NOT SATISFIED AND THE STEVEDORE REFUSES TO CARRY OUT HIS REQUIREMENTS HE MUST NOT SAIL. HE MUST ALSO BE SATISFIED THAT THE BARGE IS SEAWORTHY AND THE TOWING BRIDLE AND OTHER EQUIPMENT IS IN GOOD CONDITION. MANY ACCIDENTS HAVE HAPPENING AROUND SINGAPORE BECAUSE BARGES HAVE BEEN IN POOR CONDITION OR BADLY LOADED. CARGO HAS FALLEN OVER THE SIDE, TUGS HAVE BEEN PULLED OVER BY THE BARGE AND CAPSIZED, KILLING CREWMEMBERS AND BARGES HAVE SUNK WITH ALL CARGO ON BOARD.

The main causes of accidents are 1) LOADING CONTAINERS TOO HIGH. When a strong wind squall hits the tug and barge, the barge is blown down-wind, the tug has been pulled sideways and capsized. This especially happens when the tug is not powerful enough. There is also a likelihood that the barge will suffer a loss of stability. 2) LOADING FULL CONTAINERS ABOVE EMPTY OR LIGHT CONTAINERS This makes the barge unstable. When the barge is pulled to one side or affected by strong wind and seas during the north-east monsoon or squalls, the barge lists because it is unstable and containers fall off. There is also a likelihood that the barge will suffer a loss of stability. 3) NOT STOWING OR SECURING CARGO PROPERLY. If cargo is not stowed properly it can fall over, slide or roll across the barge. When the barge is caused to list by heavy seas, strong wind, the tug pulling to one side or being pushed to one side by another vessel the cargo shifts, causing the barge to list. Then more cargo shifts and there is a bigger list until cargo falls over the side or the barge capsizes. 4) BARGE IS IN POOR CONDITION. The steel inside the barge is wasted and there are holes between the tanks. Water entering one tank runs into the next tank, the barge starts to list and the list gets bigger as the water runs across to one side, causing the barge with cargo to capsize. 2

5) COLLISION WITH OTHER VESSELS. When crossing the Strait at night ships have collided with poorly lit barges. The collision damages the barge allowing water into a compartment. The barge lists, cargo shifts and either the barge capsizes or cargo is lost. 6) OVERLOADING Overloaded barges have been lost due to taking on water after very small collisions. When overloaded all certification and insurance cover is cancelled and the barge’s stability can be seriously affected. IT IS THE TUG MASTER’S DUTY TO TAKE PROPER PRECAUTIONS AND ENSURE THAT NONE OF THE ABOVE HAPPEN.

CONTAINER LOADING & SECURING On barges larger than length 200’ (61m), beam 50’ (15m) and draught 9’ (2.75m), heavy containers (TEU 20’ containers of 18mt-20mt & FEU 40’ containers 25-30mt) can be stowed 2 high and 3rd and 4th tiers of empty containers can be stowed on top. Alternatively a bottom tier of full containers and 3 tiers of empty containers can be carried or 4 tiers of empty containers can be carried. IF MORE CONTAINERS ARE TO BE CARRIED THE BARGES STABILITY MUST BE RECALCULATED AND THE STABILITY MANUAL CONSULTED. AT ALL TIMES THE MINIMUM REQUIREMENTS OF THE STABILITY BOOK MUST BE COMPLIED WITH. HEAVY CONTAINERS SHOULD ALWAYS BE STOWED ON THE BOTTOM TIER. THEY MUST NEVER BE STOWED ON TOP OF LIGHTER CONTAINERS. LOADED CONTAINERS SHOULD NEVER BE STOWED ON TOP OF EMPTY CONTAINERS.

Containers should be stowed fore and aft. The bottom tier should be stowed on flat dunnage laid across the barge so that the corner posts are on the dunnage. Whenever possible the containers should be stowed against the side-boards of the barge and each container should be stowed closely against the next container. Any empty space left between containers after the stow has been completed must be chocked with heavy pieces of timber and wooden wedges. THE OUTBOARD CONTAINERS MUST HAVE TWISTLOCK ON ALL TIERS AND CONTAINERS ON THE 2nd, 3rd, OR 4th TIER WHICH ARE NOT STOWED AGAINST OTHER CONTAINERS MUST HAVE POSITIONING CONES.

3

GENERAL CARGO, STEEL COILS, CABLES & PIPES STOWAGE & SECURING Wherever possible cargo should be stowed against the side-boards of the barge or against other cargo to prevent movement in case the barge lists or rolls. Lashing eyes should be welded at suitable intervals (at least every 3 meters) onto the side-boards to make lashing easy.

Cases and general cargo should be secured so that they cannot slide or fall over. They should be chocked or lashed at the bottom to prevent sliding and stowed against other cargo if possible and chocked or lashed to prevent tipping over. Alternatively they can be lashed against the side boards.

Lashing to side board

Wooden wedge

4

Steel coils should be stowed ‘on the roll’, fore & aft, with heavy wooden wedges hammered between the curve of the coil and the deck of the barge to prevent movement. They should never be stowed more than 1 high.

Bundles of pipes or wire rods can be stowed across the barge or fore and aft. Large pipes should be stowed across the barge, wooden chocks or wedges hammered between the curve of the pipe and the deck of the barge and cargo or chocking stowed against the end of the pipes.

5

LARGE, HEAVY CARGO Special care must be taken when loading and securing large, heavy cargo. It is essential to place large dunnage on the deck of the barge to spread the load. Tomming and wire lashings should be used to ensure that, even if the barge lists, the cargo will not move. If the Master is not familiar with securing heavy cargo it is recommended that he requests the assistance of an experienced surveyor to attend.

6

7

8

EXAMPLES OF CALCULATING THE BARGES STABILITY CONDITION

The following pages show various examples of calculating whether or not a barges stability complies with the barges stability criteria.

9

CALCULATING STABILITY Example 1 1st and 2nd tiers heavy 20ft containers (20T), 3rd and 4th tiers empty 20ft containers Assumption for calculation •

Each tier fully stacked at 5 rows across by 8 containers fore and aft

•

Vertical Centre of Gravity, VCG, of containers is half height = half 2.59m = 1.295m

•

Weight of heavy container = 20T, weight of empty container = 2.4T

Taking moments about the deck to calculate the total cargo vertical centre of gravity, CVCG, above the deck Tier

Total Weight Tonnes (W) 5 x 8 x 20 = 800 5 x 8 x 20 = 800 5 x 8 x 2.4 = 96 5 x 8 x 2.4 = 96 1792

1st 2nd 3rd 4th

CVCG

=

total moment total weight

VCG above deck (m) 1.295 3.885 6.475 9.065

=

5635.84 1792

Moment (W x VCG) 1036 3108 621.6 870.24 5635.84 =

3.15m

From the Summary Table on page 7 we derive by interpolation that for a cargo weight (deadweight) of 1792 we find that extreme draft is 2.48m and the maximum permissible cargo VCG above deck is 4.24m Extreme Draft (m) 2.500 2.476 2.250

Cargo VCG above deck (m) 4.058 4.242 5.950

Deadweight (T) 1815.78 1792 1570.03

The calculated CVCG of 3.15m is less than the maximum permissible CVCG of 4.24m and therefore is within the permissible stability criteria and is safe. With the extreme draft of 2.48m and the CVCG of 3.15m we can also determine using the maximum cargo VCG curve on page 8 that the load plan is in the Safe Zone (see Figure 1 on page 10).

10

example 1

0.75 1 1.5 2 2.25 2.5 2.75 3

16.906 14.199 10.161 7.548 5.95 4.058 2 0.5

0.893

0.893

3.15

2.48

11

CALCULATING STABILITY Example 2 1st and 2nd tiers heavy 40ft containers (30T), 3rd and 4th tiers empty 40ft containers Assumption for calculation •

Each tier fully stacked at 5 rows across by 4 containers fore and aft

•

Vertical Centre of Gravity, VCG, of containers is half height = half 2.59m = 1.295m

•

Weight of heavy container = 30T, weight of empty container = 4.0T

Taking moments about the deck to calculate the total cargo vertical centre of gravity, CVCG, above the deck Tier

Total Weight Tonnes (W) 5 x 4 x 30 = 600 5 x 4 x 30 = 600 5 x 4 x 4 = 80 5 x 4 x 4 = 80 1360

1st 2nd 3rd 4th

CVCG

=

total moment total weight

VCG above deck (m) 1.295 3.885 6.475 9.065

=

4351.2 1360

Moment (W x VCG) 777 2331 518 725.2 4351.2 =

3.20m

From the Summary Table on page 7 we derive by interpolation that for a cargo weight (deadweight) of 1360 we find that extreme draft is 2.03m and the maximum permissible cargo VCG above deck is 7.34m Extreme Draft (m) 2.250 2.033 2.000

Cargo VCG above deck (m) 5.950 7.337 7.548

Deadweight (T) 1570.03 1360 1328.06

The calculated CVCG of 3.20m is less than the maximum permissible CVCG of 7.34m and therefore is within the permissible stability criteria and is safe. With the extreme draft of 2.03m and the CVCG of 3.20m we can also determine using the maximum cargo VCG curve on page 8 that the load plan is in the Safe Zone (see Figure 2 on page 12).

12

Example 2

3.20 2.03

13

CALCULATING STABILITY Example 3 1st and 2nd tiers 20ft containers of 15T in weight, 3rd tier 20ft containers of 8T in weight, 4th tier empty 20ft containers Assumption for calculation •

Each tier fully stacked at 5 rows across by 8 containers fore and aft

•

Vertical Centre of Gravity, VCG, of containers is half height = half 2.59m = 1.295m

•

Weight of empty 20ft containers is 2.4T

Taking moments about the deck to calculate the total cargo vertical centre of gravity, CVCG, above the deck Tier

Total Weight Tonnes (W) 5 x 8 x 15 = 600 5 x 8 x 15 = 600 5 x 8 x 8 = 320 5 x 8 x 2.4 = 96 1616

1st 2nd 3rd 4th

CVCG

=

total moment total weight

VCG above deck (m) 1.295 3.885 6.475 9.065

=

6050.24 1616

Moment (W x VCG) 777 2331 2072 870.24 6050.24 =

3.74m

From the Summary Table on page 7 we derive by interpolation that for a cargo weight (deadweight) of 1616T we find that extreme draft is 2.30m and the maximum permissible Cargo VCG above deck is 5.60m Extreme Draft (m) 2.500 2.297 2.250

Cargo VCG above deck (m) 4.058 5.596 5.950

Deadweight (T) 1815.78 1616 1570.03

The calculated CVCG of 3.74m is less than the maximum permissible CVCG of 5.60m and therefore is within the permissible stability criteria and is safe. With the extreme draft of 2.30m and the CVCG of 3.74m we can also determine using the maximum cargo VCG curve on page 8 that the load plan is in the Safe Zone (see Figure 3 on page 14).

14

Example 3

3.74m

2.30m

15

CALCULATING STABILITY Example 4 1st and 2nd tiers heavy 20ft containers (20T) and 3rd tier 20ft containers of 10T in weight Assumption for calculation •

Each tier fully stacked at 5 rows across by 8 containers fore and aft

•

Vertical Centre of Gravity, VCG, of containers is half height = half 2.59m = 1.295m

Taking moments about the deck to calculate the total cargo vertical centre of gravity, CVCG, above the deck Tier

Total Weight Tonnes (W) 5 x 8 x 20 = 800 5 x 8 x 20 = 800 5 x 8 x 10 = 400

1st 2nd 3rd

VCG above deck (m) 1.295 3.885 6.475

Moment (W x VCG) 1036 3108 2590

2000 CVCG

=

total moment total weight

6734 =

6734 2000

=

3.37m

From the Summary Table on page 7 we derive by interpolation that for a cargo weight (deadweight) of 2000T we find that extreme draft is 2.68m and the maximum permissible Cargo VCG above deck is 2.42m Extreme Draft (m) 2.855 2.684 2.500

Cargo VCG above deck (m) 0.893 2.417 4.058

Deadweight (T) 2171.09 2000 1815.78

The calculated CVCG of 3.37m is greater than the maximum permissible CVCG of 2.42m and therefore is outside the permissible stability criteria and is NOT SAFE. With the extreme draft of 2.68m and the CVCG of 3.37m we can also determine using the maximum cargo VCG curve on page 8 that the load plan is in the UNSAFE ZONE (see Figure 4 on page 16).

16

example 4

3.37m

2.68m

17

CALCULATING STABILITY Example 5 Mixed Cargo - Container and General Cargo Stowage: Containers, tier 1 and 2 heavy (20T), tiers 3 and 4 empty (2.4T) x 4 bays, Frames 2 – 16 Boxes, General, Stowed to 3.8m high, total 325T, Frames 16 - 20 Steel Coils, 1.5m dia x 2.4 width x 12T, stowed fore and aft ‘on the roll’, 3 rows x 9 coils per row, Frames 20 -24 Pipes, 40ft x 30ins dia x 7T, stowed across the barge, stacked 3 high, Frames 24 - 30 Assumption for calculation • • • •

Vertical Centre of Gravity, VCG, of containers is half height = half 2.59m = 1.295m Vertical Centre of Gravity, VCG, of boxes is half height = half 3.8m = 1.9m Vertical Centre of Gravity of coils is half diameter = half 1.5m = 0.75m Vertical Centre of Gravity of pipe is half diameter = half 0.762m = 0.381m

Taking moments about the deck to calculate the total cargo vertical centre of gravity, CVCG, above the deck Cargo Frames Tier Containers 2 -16 1 2 3 4 Sub total

Wt (T) 5x4x20= 400 5x4x20= 400 5x4x2.4= 48 5x4x2.4= 48 896

VCG(m) 1.295 3.885 6.475 9.065

Moment 518 1554 310.8 435.12 2817.92

Boxes

16 – 20

1

325

1.9

617.5

Coils

20 – 24

1

3x9x12 = 324

0.75

243

Pipes

24 – 32

1 2 3

0.381 1.143 1.905

Sub total

14x7=98 13x7=91 12x7=84 273

37.34 104.01 160.02 301.37

Totals

1818

18

3979.79

CVCG

=

total moment = 3979.79 = 2.19m total weight 1818 From the Summary Table on page 7 we derive by interpolation that for a cargo weight (deadweight) of 1818T we find that extreme draft is 2.50m and the maximum permissible Cargo VCG above deck is 4.04m Extreme Draft (m) 2.855 2.504 2.500

Cargo VCG above deck (m) 0.893 4.038 4.058

Deadweight (T) 2171.09 1818 1815.78

The calculated CVCG of 2.19m is less than the maximum permissible CVCG of 4.04m and therefore is within the permissible stability criteria and is safe. With the extreme draft of 2.50m and the CVCG of 2.19m we can also determine using the maximum cargo VCG curve on page 8 that the load plan is in the Safe Zone (see Figure 5 on page 19).

19

Example 5

20