1

Loading and Unloading Containers: Examining the Efficiency of Goods Movements

Hsien-Yang Yeh, *Hen-Geul Yeh, and Panchali Choudhury

Mechanical and Aerospace Engineering Department *Electrical Engineering Department

California State University, Long Beach

Acknowledgement This project wouldn’t have been possible without the generous help we received from various individuals. Dr. Domenick Miretti, ILWU Senior Liaison ports of LA and LB, was the most experience and knowledge about the LA and LB terminals. He explained to us the safety problem and efficiency related crane operation procedures to us. We are extremely grateful to Mr. Richard Joe and Peter Yin from Engineering Division Port of Los Angeles whose valuable inputs regarding the kinds of cranes used in the port of LA. Many thanks also, to Ms. Rachel Campbell, who very kindly advised us to see Mr. Richard Joe. Thanks to Robert J. Perry, manager of crane operations/administrations at APM Terminals, and Daniel M. Blackburn, Manager Systems/Process Development, toured and briefed us about the APM terminal operation. Thanks to Tim Kennedy, manager of PMA (Pacific Maritime Association) and Gale W. Searing Director, West Coast Hamburg Sud North America, Inc.. Many thanks to Dr. Tom O'Brien, Director CITT. Many thanks to George Wan Captain/Yard Manager and Tony Teng of Yang Ming Mariine Transport Corp., Charles Zhao, President of West Basin Container Terminal (WBCT), Steven Hinds, Program Coordinator, CCDOTT.

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Table of Contents Summary ....................................................................................................................................3 1 Port of Los Angeles and Port of Long Beach.......................................................5

1.1 Port of Los Angeles [1] .................................................................................................... 5 1.1.1 Factual Information [1].......................................................................................5 1.1.2 Annual Statistics[1] .............................................................................................6 1.1.3 The Crane Terminals at the Port of LA [1]..........................................................7

1.2 Port of Long Beach [3]..................................................................................................... 8 1.2.1 Annual Statistics [2]............................................................................................9

1.3 Comparison Between the Annual Statistics of Ports of LA and LB… ……….. 11 1.4 Piers and Berths at Port of Long Beach [4] ......................................................13

2 Study of Port Loading and Unloading Procedures.............................................15 2.1 Work Flow of the Port.................................................................................................... 16 2.2 General Port Layout for Moving Containers................................................................... 17

2.2.1 Loading and Unloading Containers from Ship to Land......................................17 2.3 Loading and Unloading Containers From Land to Storage Area .......................22

2.4 Reclaimer ....................................................................................................................... 25 2.5 Container Dimensions .......................................................................................26

2.6 Type of Containers.……………………….. ………………… 26 3 Safety and Efficiency of Container Movement ..................................................27

3.1 Safety Analysis of the Container Cranes ........................................................................ 27 3.2 Dynamic Model of the Crane [8].................................................................................... 27

3.2.1 Outside Effect [10]............................................................................................28 3.2.2 Determination of Dynamic Load .......................................................................29 3.2.3 Loads During Stopping [10], [9] .......................................................................29 3.2.4 Load Induced Due to Passage Over Obstacles [10],[9]....................................30 3.2.5 Dynamic Load Due to Skewness [10], [9] ........................................................30

3.3 Analysis of the Schedule for Efficiency .......................................................................... 30 3.3.1 Factors Affecting the Work Flow .......................................................................31

3.4 GPS (Global Positioning System) ...................................................................................32 3.4.1 Auto Sterring Technology…………………………………………………………………………………….34 3.4.2 Pier Pass [11]: ..................................................................................................33 3.4.3 Success of Pier Pass [11] ..................................................................................34 3.4.4 Alameda Corridor [14],[15] ..............................................................................35

3.5 Conclusion and Recommendations ....................................................................36 4 APPENDIX .........................................................................................................37 5 References ........................................................................................................37

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SUMMARY

The report aims to present a preliminary study and analysis of the types of crane being used, the

loading and unloading procedures and the technologies at the two ports, the Port of Long Beach and the

Port of Los Angeles. The report highlights some significant statistical facts and suggests some areas of

potential improvement to increase the productivity of these two ports.

The first half of the Section 1, Port of Los Angeles and Port of Long Beach, goes on to describe

some important facts about the Port of Los Angeles and the kind of cargo that is loaded and unloaded at

the port. It also describes the statistical data of the number of containers, both empty and loaded that

were handled since 1995. Apart from this, the report also talks about the kind of cranes used and its

corresponding terminals at the Port of LA. The second half of the Section 1 is dedicated to the annual

statistics at the Port of Long Beach since 1995. The Section also highlights the different terminals at the

port. The terminals are categorized in terms of the methods used to store the cargo handled i.e.

Containerization, Dry bulk, Liquid bulk etc. Section 1 also analyses the statistical data of the containers

handled at both the ports, representing them in form of graphs. The change in the statistics is also

clearly in the form of graphs.

In Section 2, the port loading and unloading procedures are studied. It is elaborated on the

general view of a port and its workflow. The report outlines a typical port job-flow, the kind of

containers and the cranes that are available for the port in the market scenario. This helps us to put forth

a clear picture of the procedures in the port and helps us to understand the port operation.

In Section 3, safety and efficiency issues are discussed alone with conclusions and

recommendations. Four major suggestions are made including future research areas, which can

improve the efficiency of the job-flow (i.e. the number of containers moved during a time frame) and

ultimately can increase the level of productivity.

• The report suggests a proper time management or schedule management in the loading and

unloading procedures from ship to inland storage areas.

• The report also suggests the use of GPS in the loading and unloading of the containers

• As seen in the Annual Statistics of both the ports, it is observed that the Port of Long Beach and

the Port of Los Angeles, handles empty containers which are some times more than the number

of loaded containers handled by the port. Thus suggestions have been made to further

4

investigate a better manage the resources used to handle the empty containers, especially out-

bound procedures.

• The report highlights an advantage of using cranes such as dual hoisting and twin lift capability

cranes, factual information has been provided. Ports may consider these cranes, if applicable.

While certain suggestions have been made, the report does appreciate changes brought

about by as explained in Section 3. Pier-Pass increases the container transports in and out by

changing the truck schedules from the peak day hours to off-peak hours thus decreasing congestion

on the roads. Alameda Corridor connects the national rail system near downtown Los Angeles

California to the ports of Los Angeles and Long Beach, running parallel to Alameda Street thus

decreasing congestion in the railway system, which further increases container-handling rate of

both the ports.

1 PORT OF LOS ANGELES AND PORT OF LONG BEACH

1.1 Port of Los Angeles [1]

The Port of Los Angeles which is located in San Pedro Bay just 20 miles south of down town

Los Angeles is known to be the backbone of Southern California’s international commerce. This

seaport is known for its competitive edge with cargo operations, security measures and safety measures.

This Port is often referred as Los Angeles Harbor Department. The Port covers 7500 acres of land, 43

miles of waterfront and boasts of 26 cargo terminals, including dry and liquid bulk, container, break

bulk, automobile and omni facilities. Combined, these terminals handle more than 162 million metric

revenue tons of cargo annually. The Port (as shown in Figure 1) is also home to the nation's most

secure cruise passenger complex, the World Cruise Center.

Figure 1. The Port of Los Angeles.

1.1.1 Factual Information [1]

The Port of LA, founded in the year 1907, has been ranked as the busiest container port in The

United States, the 8th busiest container port in the world and the 5th busiest container complex in the

world when combined with the neighboring Port of Long Beach. Major containerized imports of the

port are Furniture, Toys, Electronics Equipment, Footwear, and Women‘s and Infant Wear. Major

containerized exports of the Port are Paper Products, Fabric, Pet and Animal Feed, Mixed Metals Scrap,

and Soybean.

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1.1.2 Annual Statistics [1]

In order to find out the average cargo that is loaded and unloaded each year, an in- depth study

of the annual statistics was done and tabulated as shown in Table 1.

Table 1: Annual statistics of the LA port.

Year Loaded Inbound TEUs

Empty Inbound TEUs

Loaded Outbound TEUs

Empty Outbound TEUs

Total (In and Out) TEUs

Jan 2007- April 2007

1,400,163.65

4,516.35 494,410.75

731,350.65 2630441.4

Jan 2006- Dec 2006

4,408,185.25 79,165.15 1,423,619.90 2,558,882.70 8,469,853.00

Jan 2005-Dec 2005

3,881,326.05 74,727.25 1,171,230.50 2,357,340.65 7,484,624.45

Jan 2004-Dec 2004

3,940,419.90 63,360.90 1,129,880.00 2,187,779.30 7,321,440.10

Jan 2003-Dec 2003

3,814,473.25 75,851.45 1,163,344.60 2,125,270.80 7,178,940.10

Jan 2002-Dec 2002

3,232,411.15 130,958.55 1,093,806.70 1,648,686.75 6,105,863.15

Jan 2001-Dec 2001

2,683,657.05 117,832.45 1,037,794.70 1,344,235.70 5,183,519.90

Jan 2000- Dec 2000

2,492,546.30 119,725.60 984,650.90 1,282,505.80 4,879,428.60

Jan 1999- Dec 1999

1,965,852.65 98,175.80 817,580.55 947,241.50 3,828,850.50

Jan 1998-Dec 1998

1,715,414.30 124,949.00 794,668.05 743,187.35 3,378,218.70

Jan 1997- Dec 1997

1,462,621.90 138,422.15 870,925.85 487,743.60 1,358,669.45

Jan 1996- Dec 1996

1,293,474.55 155,157.95 836,435.70 397,957.70 2,683,025.90

Jan 1995-Dec 1995

1,251.600.40 136,403.60 824,325.85 342,876.10 2,555,205.95

Note: Total = Loaded Inbound + Loaded Outbound + Empty Inbound + Empty Outbound

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1.1.3 The Crane Terminals at the Port of LA [1]

The Port stretches within an area of 7500 square miles (3300 water and 4200 Land) and

features 27 cargo terminals of Automobile, Break bulk, Container, Dry Bulk, Liquid Bulk, Warehouse.

The following two tables list the cranes and the related technical details used at the Port of LA. The

port has two kinds of cranes, the customer owned cranes and the Los Angeles Port owned cranes. Table

2 shows the port of LA owned container cranes and Table 3 shows the customer owned cranes with

technical data.

Table 2: Port of LA owned container cranes.

Terminal

Manufa

cturer

Lift

Height

(ft)

Back

Reach

(ft)

Rail

Gauge

(ft)

Set

Back

(ft)

Out

Reach

(ft)

Inside

Spacing

(ft)

Trolley

Speed

(length/

minute)

Hoist

(horse

power)

Ship

Service

Capability

209-18

Hitachi

85

50

50

7.3

112.9

55

500

250

13

209-19

Hitachi

85

50

50

7.3

112.9

55

500

250

13

209-13

Paceco

80

50

50

8.6

111.6

50

500

200

13

209-12

Paceco

100

50

50

8.6

111.6

50

500

200

13

209-14

Hitachi

85

50

50

7.3

112.9

55

500

250

13

209-15

Hitachi

85

50

50

7.3

112.9

55

500

250

13

209-16

Hitachi

85

50

50

9.6

110.6

55

500

250

13

209-08

Paceco

78

40

50

7.3

112.9

46

500

250

13

209-34

Paceco

80

40

50

7.3

112.9

46

400

250

13

209-11

ISI

80

40

50

8.6

111.9

50

400

250

13

209-08

ISI

80

40

50

7.3

112.9

50

500

500

13

209-10

ISI

80

40

50

7.3

112.9

50

500

500

13

209-35

Mitsui

90

60

34

8.0

112

55

None

None

13

8

Table 3: Customer owned container cranes.

Terminal

Manufacturer

Lift

Height

(ft)

Back

Reach

(ft)

Rail

Gauge

(ft)

Set

Back

(ft)

Out

Reach

(ft)

Inside

spacing

(ft)

Electric

Power

(KV)

Ship

Service

Capability

Hitachi

Paceco-itsu 100 35 100 7.25 127.75 65 4.16

Bus Bar

13

Trapac Paceco-itsu 110 35 100 7.25 170.6 65 4.16

Bus Bar

18

Trapac Paceco-itsu 110 35 100 7.25 165 46.25 4.16

Bus Bar

19

Trapac Mitsubushi 105 50 100 7.25 137.75 60 4.16

Bus Bar

16

NYK Mitsubushi 114.5 50 100 7.25 135 55 4.16

Bus Bar

18

NYK Noell 110 50 100 20.67 160 60 4.16

Cable

19

Maersk ZPMC 130 74.75 100 20.67 189.3 60 4.16

Bus Bar

22

China

Shopping

ZPMC 120 74.75 100 7.75 190 60 4.16

Cable

Reel

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1.2 Port of Long Beach [3]

Port of Long Beach is one of the world’s busiest seaports in United States. The port

encompasses almost 3,200 acres of land, 10 piers, 80 berths and 71 post Panamax gantry cranes. About

$5.4 billion a year in U.S. Customs revenues are derived from the Long Beach. Also the port builds

revenue of $4.9 billion a year in local, state and general federal taxes from Port-related trade, more than

$47 billion in direct and indirect business sales yearly and about $14.5 billion in annual trade-related

wages. Top imports and exports of the Port comprises of Machinery Electrical Machinery, Vehicles,

Toys and Sports Equipments and Bedding. The map of Long Beach port is shown in Figure 2.

Figure 2. The map of Long Beach.

The Port of Long Beach’s facilities include information on the cargoes handled, berth

specifications, special equipment and company contacts. The piers and berths are divided into four

categories: Containerized cargoes, Dry Bulk cargoes, Liquid Bulk cargoes and Break Bulk cargoes.

1.2.1 Annual Statistics [2]

Similar to the Los Angeles Port analysis, a detailed study of the Port of Long Beach was done.

Table 4 presents the annual statistics of the port Long Beach in terms of containers.

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Table 4: Annual statistics of the port of Long Beach.

Year

Loaded In bounded

TEUs

Loaded Out Bounded

TEUs

Total Loaded TEUs

Empties TEUs

Total Containers

TEUs Jan 2007- Apr 2007 2,412,166 919,200 3,331,366 1,408,855 4,740,221 Jan 2006 – Dec 2006 3,719,680 1,290,843 5,010,523 2,279,842 7,290,365

Jan 2005 – Dec 2005 3,346,054 1,221,419 4,567,473 2,142,345 6,709,818

Jan 2004 – Dec 2004 2,987,980 1,007,913 3,995,893 1,783,959 5,779,852

Jan 2003 – Dec 2003 2,409,577 904,539 3,314,116 1,344,008 4,658,124 Jan 2002 – Dec 2002 2,452,490 855,202 3,307,692 1,218,673 4,526,365

Jan 2001 – Dec 2001 2,420,687 952,845 3,373,532 1,089,435 4,462,967 Jan 2000 – Dec 2000 2,456,188 1,044,353 3,500,541 1,100,246 4,600,787

Jan 1999 – Dec 1999 2,317,050 989,221 3,306,271 1,102,209 4,408,480

Jan 1998 – Dec 1998 2,096,901 973,647 3,070,548 1,027,141 4,097,689

Jan 1997 – Dec 1997 1,806,787 1,107,324 2,914,111 590,491 3,504,602

Jan 1996 – Dec 1996 1,547,578 1,081,887 2,629,465 437,869 3,067,334 Jan 1995 – Dec 1995 1,353,320 1,036,213 2,389,533 453,969 2,843,502

1.3 Comparison Between the Annual Statistics of Port of LA and Port of Long Beach

The annual statistics of Tables 1 and 4 of both the ports are analyzed and plotted with X –Axis having

the year and Y -Axis having the number of containers handled. Figure 3 shows the loaded in-bound

containers of Ports of LA and LB. The loaded in-bound containers has increase about three times in the

past 11 years. Figure 4 shows loaded out-bound containers of Port of LA and LB. Figure 5 shows

loaded out-bound and in-bound, empty out-bound and in-bound containers of Port of LA. The

significant finding is that the empty out-bound containers are about twice more than the loaded out-

bound container of LA port in 2006. This trend has been continuing and will keep going up for another

decade. Therefore, a study on how to handle empty container is needed, especially for out-bound

operation for port LA.

Loaded In bound TEUs

5.0E+05

1.0E+06

1.5E+06

2.0E+06

2.5E+06

3.0E+06

3.5E+06

4.0E+06

4.5E+06

5.0E+06

1995 1997 1999 2001 2003 2005 2007Year

Num

ber o

f Con

tain

ers

LA-Loaded In bound

LB-Loaded In bound

Figure 3. Loaded In-bound container of Ports of LA and LB.

Loaded Out bound TEUs

2.0E+05

4.0E+05

6.0E+05

8.0E+05

1.0E+06

1.2E+06

1.4E+06

1.6E+06

1995 1997 1999 2001 2003 2005 2007Year

Num

ber o

f Con

tain

ers

LA-Loaded Outbound

LB-Loaded Out Bound

Figure 4. Loaded Out-bound container of Port of LA and LB.

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LA - Loaded and Empty TEUs

0.0E+005.0E+051.0E+061.5E+062.0E+062.5E+063.0E+063.5E+064.0E+064.5E+065.0E+06

1995 1997 1999 2001 2003 2005 2007Year

Num

ber o

f Con

tain

ers

Loaded In BoundEmpty In BoundLoaded Out BoundEmpty Out Bound

Figure 5. LA port inbound, outbound, loaded, and empty containers.

These graphs compare the loaded in-bound containers and loaded out bound containers of both The Port

of LA and The Port of Long Beach. It is apparent that both the ports have shown a decent rise in the

number of containers handled since the year 1995. This is a good way to prove that the plans like Pier

Pass and Alameda Corridor (as explained in details in Section 3) have been successful to increase the

number of containers handled. The Port of LA shows higher in-bound and out-bound loaded containers

than that of Long Beach port. Figure 6 shows the total empty containers (both in-bound and out-bound)

of ports of LA and LB. Again, the Port of LA shows higher empty containers than that of Long Beach

port. Also the number of empty containers handled rises from 1995 to 2006. It is thus suggested to

note that the resources used handle the empty containers and the ones used for loaded could be better

managed for a better production level for both ports.

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Total Empty TEUs

0.0E+00

5.0E+05

1.0E+06

1.5E+06

2.0E+06

2.5E+06

3.0E+06

1995 1997 1999 2001 2003 2005 2007Year

Num

ber o

f Em

pty

Con

tain

ers

LA-Total EmptyLB-Total Empty

Figure 6. Empty containers of Port of LA and LB.

1.4 Piers and Berths at Port of Long Beach [4]

In this report, we focus on container movement. Although other goods movement is important

and mentioned here, it is out of the scope of this project. However, we list these goods at port together

with containers for completeness.

1.4.1.1 Containerization

Primarily finished goods like clothes, toys, and furniture are containerized. Liquids and other

unique cargoes may be shipped in specialized containers. The following are privately owned Terminals

for containerization at the Port of Long Beach:

• California United

• TTI / Hanjin Shipping Co

• International Transportation Service

• Long Beach Container

• Pacific Container

• SSA Terminals

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1.4.1.2 Dry Bulk

Dry cargoes shipped in bulk are measured by weight or volume (primarily tons), not by count. Cargoes

like petroleum coke, gypsum, salt and grains fit in this category. The following are privately owned

Terminals for dry bulk at the Port of Long Beach:

• G.P. Gypsum

• Koch Carbon, Inc

• Metropolitan Stevedore Co

• Mortons Salt

• National Gypsum Co.

• Pacific Coast Cement

1.4.1.3 Liquid Bulk

Liquid forms of bulk cargo are measured by weight or volume (primarily tons). Commodities like crude

oil, gasoline and miscellaneous chemicals are common liquid bulk cargoes. The following are privately

owned Terminals for liquid bulk at the Port of Long Beach:

• Baker Commodities Inc

• BP Pipeline - Pier T

• BP Pipeline - Pier B

1.4.1.4 Break & Roll On- Roll Off

Large or heavy items such as steel, lumber, machinery and food products moved on pallets are Break

Bulk cargoes. Roll On-Roll Off cargoes are items that are driven on and off a vessel.

2 STUDY OF PORT LOADING AND UNLOADING PROCEDURES

In order to exam the loading and unloading procedures of the ports, detailed study of both

the ports was done. The Los Angeles Port Layout (Fig. 7), for example, provides us with detailed and

clear view of locations of the various cranes, terminals at which the containers are unloaded or loaded,

the area where the ship docks etc.

Figure 7. The Port of LA – Layout.

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2.1 Work Flow of the Port

The workflow of the port begins at the stage where the container is loaded or unloaded from the

ship wharf to the terminals at the shore by quay cranes. Container carrying cranes then moves these

from the shore to the storage areas. The crane classifications are described in the coming Sections and

the job flow is as shown in the Figure 8.

Ship to wharf

Loading or unloading done along the wharf over a ship via cranes

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Figure 8. Flow chart of the container loading and unloading procedure.

Wharf to Land

Terminal loading or unloading on Land via cranes

Terminal to storage area

Container loading and unloading done from terminal to the storage area via trains or trucks

2.2 General Port Layout for Moving Containers

As mentioned in Section 1, the Port of LA has two types of cranes terminals (the customer

owned cranes and the Los Angeles Port owned cranes) to support the job flow shown in Figure 8. They

are classified as the ones used to transfer containers between ship and land and the ones used to transfer

containers between land and the storage area. An internet search on current crane types is conducted

along these two categories. They and their sub- type are discussed with pictures in the following

Sections.

2.2.1 Loading and Unloading Containers from Ship to Land

As shown in the port map (Figures 1 and 2), container cranes do the dockside loading and

unloading. The conventional quay side container cranes are popular for loading and unloading

containers from ship to shore and vice versa. Figure 9 shows the quay side container cranes. Note that

they can be used as the link between shore to the trucks as well as ship to shore cranes.

Figure 9. Conventional Quay side container cranes.

Another one of such a container crane is the “modified A frame” container crane manufactured

by Paceco (as shown in Figure 10). The studies done in this report is mainly on this 4th generation

Paceco container crane since it is considered as one of the best designed having fewest number of

pieces. History of the Paceco cranes began in the early 1958 when under the leadership of then –

President Dean Ramsden the company began to make conceptual drawings paying particular attention

to aesthetics resulting A frame configuration, for which Paceco later became very famous. This was

over a period of time was further modified and what we have today is the 4th generation Paceco 17

container crane of ‘modified A frame‘. The container cranes also include dual hoist machinery cranes

and twin hoist capability cranes.

Figure 10. A- Frame First Generation Paceco Cranes [5].

Dual hoist refers to a crane that is equipped with separate hoist machines in one crane structure.

The working of the hoist is such that one of the two hoists will handle the container between the ship

and a platform on the crane, the second lifts the containers between the platforms to the ground. The

Twin lift however works different from the dual hoist. The twin lift (as shown in Figure 11) crane is

capable of picking up two containers at a time, which makes the work go faster eventually increasing

the productivity.

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Figure 11. Twin Lift Cranes [6].

2.2.1.1 Rail Mounted Container Gantry Cranes

It is used as quay as well as crane link to shore and storage. Figure 12 shows a rail mounted

container gantry cranes. Note that it may be used for both ship to shore and for containers handling.

This is a specialized yard container handling machine. It can travel on rail by means of the yard power,

and lift and stack containers in the yard area with the equipment of the 20’ or 40’ telescopic spreader

(or twin-lift spreader if needed). Compared with the rubber-tyred gantry crane (RTG), the RMG has the

advantages of being driven by electrical power, clean, bigger lifting capacity, and high gantry traveling

speed with cargo. The RMG consists of lifting mechanism, trolley traversing mechanism, gantry

mechanism and sway-dampening mechanism. Figure 13 shows main hub gantries.

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Figure 12. Rail mounted container gantry cranes.

Figure 13. Main Hub Gantries.

2.2.1.2 Floating Cranes [8]

Floating Cranes used (as seen in the Figure 14) for occasional loading and unloading

of especially heavy or awkward loads on and off ships. Some floating cranes are mounted on a pontoon,

others are specialized crane barges with a lifting capacity exceeding 10,000 tones and have been used to

transport entire bridge sections. Floating cranes have also been used to salvage sunken ship.

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Figure 14. Floating cranes.

2.2.1.3 Double Boom Crane

Figure 15 shows double boom cranes. These cranes offer high transshipment capacity, suitable

for all types of cargo Multi-purpose terminals, especially, will benefit from this crane, but even if it will

only be used for hook, spreader, or grab duty, KENZ-FIGEE double boom crane will get excellent

results.

Figure 15. Double Boom Cranes.

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2.3 Loading and Unloading Containers from Land to Storage Areas

2.3.1 Loading and Unloading Containers from Land to Storage Area

The terminal loading and unloading on land is often done by Rubber Tire Gantry cranes. The

equipment is used to arrange and stack the containers in the container yard in a systematic manner for

transit.

2.3.1.1 Rubber Tyred Gantry Cranes

Rubber-tyred gantry RTG (Figure 16) cranes can be classified in to two based on wire rope revving

system. One is provided with mechanical sway—damping system with four anti-sway wire ropes and

the other one with eight anti-sway wire ropes (which can achieve bi—directional anti-sway). Figure 17

shows an inland terminal with cranes. Figure 18 shows a bulk handling machinery.

Figure 16. Rubber Tyred Gantry Cranes.

Figure 17. Inland terminal cranes.

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Figure 18. Bulk handling machinery.

The following are the types of cranes that are conventionally used to transfer containers on land.

There are special vehicles such as empty container handlers, loaded container handlers etc, to move

the cargo to the storage areas. The Figures 19 - 21 shows the different vehicles used to carry load

from land to storage area.

Figure 19. Loaded container handlers.

Figure 20. Empty container handlers.

23

Figure 21. Trailer and container handlers.

2.4 Reclaimer

A reclaimer (Figure 22) recovers and transports bulk materials from yard stockpiles onto the conveyor.

Figure 22. Reclaimer.

2.5 Container Dimensions [7]

Container dimensions are of five common standard lengths, 20 ft (6.1 m), 40 ft (12.2 m),

45ft (13.7ft), 48ft (14.6m), and 53 ft (16.2 m). Container capacity by US domestic standards is 20foot

containers designated as TEU (Twenty Equivalent foot) and 40foot containers designated as 2 TEU. A

twenty-foot equivalent unit is a measure of containerization cargo capacity equal to one standard 20 ft

(length) x 8 ft (width) x 8 ft and 6 inches (height). The maximum gross mass for a 20ft dry cargo is

24,000kg and for a 40 ft. is 30,480 kg.

2.6 Types of Containers [7]

Figure 23 shows a typical way of stocked containers in a ship.

24

Figure 23. Stacked containers on a ship.

Types of standard containers are as follows:

General purpose dry van for boxes, cartons, cases, sacks, bales, pallets, drums in standard, high or

half height

High cube pallet wide containers for euro pallet compatibility

Reefers.

Open top bulk containers for bulk minerals, heavy machinery

Open side for loading oversize pallet

Flush folding flat-rack containers for heavy and bulky semi-finished goods, out of gauge cargo

Platform or bolster for barrels and drums, crates, cable drums, out of gauge cargo, machinery, and

processed timber

Ventilated containers for organic products requiring ventilation

Tank containers for bulk liquids

Rolling floor for difficult to handle cargo

Gas bottle

Generator

Collapsible ISO

2.6.1 Reefers

Reefer are refrigerated containers used in inter modal freight transport for transportation of

temperature sensitive cargo. The temperature within the reefers is maintained between (from -25°c to

+25°c). While a reefer will have an integral refrigeration unit, they rely on external power to power

them, from electrical power points at a land based site. When being transported over the road on a

25

26

trailer they can be powered from diesel powered generators which attach to the container whilst on road

journeys.

2.6.2 Breaking Bulk

In ship gpin it is a maritime term for the taking out of a portion of the cargo of a ship or the

beginning of the unloading process from the ship's holds. Break bulk cargo is typically material stacked

on wooden pallets and lifted into and out of the hold of a vessel by cranes on the dock or aboard the

ship itself. The volume of break bulk cargo has declined dramatically worldwide as containerization has

grown.

2.6.3 Bulk Cargo

It is cargo that is unpacked (un-bundled or un-bound) and is of the same or a similar kind or

nature (homogeneous). These cargos are usually dropped or poured, with a spout or shovel bucket, as a

liquid or solid, into a bulk carrier's hold, railroad car, or truck/ trailer/ semi-trailer body. Bulk cargos are

classified as liquid or dry. The largest bulk carrier cargo ship in the world is the iron ore carrier Berge

Stahl, weighing a massive 364,768 dead-weight-tons (metric). The busiest bulk cargo port in the world

is the New Orleans-area based Port of South Louisiana.

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3 SAFETY AND EFFICIENCY OF CONTAINER MOVEMENTS

The productivity of port operations depends heavily upon the movement of goods through the port, which

includes considerations of labor, terminal operations, and many other related issues. By improving quay crane

efficiency, ports can reduce the ship turn-around time, improve container terminal productivity and

throughput in the freight transportation system. On the other hands, crane operators visually load and unload

containers from a starting position to the destination. The process may be slow and may not be accurate,

especially the stacking up of containers to several stories high. For safety reasons, this loading and unloading

process must be done very carefully, and then slow down the process. Clearly, these two requirements are

conflicted each other. In this Section, we perform the safety analysis based on the dynamic loading.

Furthermore, we also propose several research areas for improving the port productivity. We must point out

that most terminals are doing well. The average loading or unloading rate is about 27 – 35 containers per

hour depending on weather condition. Notice that the average loading or unloading rate of port of Baltimore

is also about 35 containers per hour in good weather circumstance. We must employ high tech devices at

terminal in order to improve loading or unloading rate when weather permits.

3.1 Safety Analysis of the Container Cranes

In this Section, we analyze and formulate the possible dynamic load acting on the container crane at

the ports. We consider the 4th generation Paceco container crane at the Los Angeles port for dynamic

analysis. We assume the load carried at the port by the container of 20ft is 24,000 kg as per the standards. The

loads are divided into internal and external loads for convenience of analysis. It is assumed that the external

ones cause the internal loads. It is clear that the external load acting on a crane includes the weight of the load

being handled and the wind load.

3.2 Dynamic Model of the Crane [8]

The cyclic operations of a crane necessitate acceleration and deceleration during each motion. This

induces dynamic load. For analysis of the dynamic load acting on the crane in practical situations, we

consider dynamic load at a limited number of points of the system. For simplicity, Figure 24 shows a dynamic

model of the crane with two masses m1 and m2.

Figure 24. Dynamic model of the crane.

The following terms are used to model the crane as depicted in Figure 24. The Elements BE,CE, DE, AE are

the links. Element F is the base of the crane. Here m1 is the vertical component of the total load bored by the

crane, and m2 is the horizontal component of the total load bored by the crane. This diagram is constructed

with the following assumptions which are based on the various loadings explained in the previous Sections:

Complicated dynamic system with many degrees of freedom may be replaced by equivalent system with

two or three masses.

The clearance does not exert any significance effect on the transient processes.

The resistance in mechanism and metal structures, appearing during motion has little effect on the

amplitude in the first vibration period.

Vibration is neglected all together in extreme case.

A comprehensive listing of these assumptions and the related mathematical modeling is explained in detail in

[9] and [10].

3.2.1 Outside Effect [10]

The external forces exerted by the prime mover , brake or buffer stops on the crane which is either

stationary or moving at constant speeds; this force may be assumed to be independent of the

conditions of motion.

Stopping forces viz. impact by the crane moving at constant speed by one of its parts, or by the load

against the crane with the ensuing cessation of motion.

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Passage over obstacle

Changes in the mass of moving parts of the crane or of the crane as whole.

3.2.2 Determination of Dynamic Load

We proceed from mathematical models and consider first the basic theoretical case, namely that of

motion under the influence of a constant excess force which is independent of the motion itself. The driving

element of the system imparts a constant linear (γ ) and angular acceleration (ε ).

Pm

γ =∑

Ml

ε =∑

where,

P = Excess load (N)

m = Summation of the masses m1 and m2 (kg)

M = Excess momentum (N-m / sec)

l∑ = Summation of the momentum I1 and I2 (N-m / sec)

Dynamic load in all cases is then determined as,

Dynamic Load (N)

F m Kγ= × ×

where,

K is the coefficient through which the vibrations are taken in to account

3.2.3 Loads During Stopping [10], [9]

The kinetic energy of a crane stopped by impact during coasting is transformed in to potential strain energy.

The maximum dynamic load ( stopP ) is

2stopv c TP

π× ×

=×

where,

v = speed of the motion (m/s)

c = structural rigidity of the crane(Nm/s)

T = time period(s)

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3.2.4 Load Induced Due to Passage Over Obstacles [10],[9]

Investigations have shown that even in complex cases, where one wheel of a rubber tired crane passes over an

obstacle, the vibrations have fundamental frequency. It is therefore possible to determine the load

approximately by considering a single mass system. The dynamic load due to passage over obstacles ( )

is:

passP

2 sin( ) sin( )1

passh pP pt

wpw

ω⎛ ⎞= × − ×⎜ ⎟⎝ ⎠⎛ ⎞− ⎜ ⎟

⎝ ⎠

t

vplπ

= Where p is the frequency of the vibration of the spring mass system representative of the

mathematical model of the crane as it passes over the obstacle.

v = is the speed of motion.(m/s)

h = height of the obstacle (m)

c = structural rigidity of the frame

w = Natural frequency of the crane

t = time

3.2.5 Dynamic Load Due to Skewness [10], [9]

Numerous experiments and analysis have shown that starting and stopping of the propulsion drive a

crane moving on rails is accompanied by dynamic load due to propulsion.

In general, the cranes are deigned well and require regular maintenance. Hence, safety is guaranteed.

Without human error in operation, the crane should work as expected. For the operation of boom cranes a

significant high level of experience is needed to achieve a large amount of handled containers. Therefore, the

training for crane operator is important.

3.3 Analysis of the Schedule for Efficiency

A detailed study of the job flow of the port indicates that schedule is another important area which may

improve the productivity. A good way to look in the schedule of the process is discussed in the following

Section that we have come across earlier in the report.

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31

3.3.1 Factors Affecting the Work Flow

On analyzing the work flow, it was observed that the daily procedures and the corresponding time

consumption depend largely on the following factors:

• The Port has hours when the workers rest.

• There are situations when the cranes are stopped due to breakdowns.

• Unfavorable weather conditions.

• Transfer of the cranes from one operating station to the other.

• The time gap between one modes of transport to the other.

• Many repeated loading and unloading of the containers in the processes in the job flow.

Elaborating the last point that said that the time gap between each mode i.e. from the container crane to the

terminal and then to the storage if managed well in streamline operation can actually make a huge difference

in the time saving. Hence improve the port productivity. Let us consider the time between wharf loading to

land loading as T1, and then land loading to terminal loading as T2, the time between terminal loading and

storage to be T3. If the container delivery is scheduled and operated well without any delay, we observe that

the time gap between T1, T2 and T3 can be minimized. Hence, good scheduling can prove to be beneficial

for the efficiency without extra loading and unloading operations.

Also to improve productivity, containers should be loaded and unloaded accurately and quickly for

the fast movement of goods in good weather condition at terminal. In fact, one of the bottlenecks at ports is

quay crane availability. By improving quay crane efficiency, ports can reduce the ship turn-around time,

improve container terminal productivity and throughput in the freight transportation system. In the next

Section, we focus on the crane productivity at a container terminal loading from ship to land and vice versa

assuming that there is no berth congestion.

3.4 GPS (Global Positioning System)

In general, crane operators visually load and unload containers from a starting position to the

destination. The process may be slow and may not be accurate, especially the stacking up of containers to

several stories high. For safety reasons, this loading and unloading process must be done very carefully, and

then slow down the process.

Use of GPS (Global Positioning System) in the cranes and in the vehicles is another helpful factor for

a more efficient output. To understand the GPS aided crane, let us consider the diagram illustrated in Figure

25. A crane driver is at least 125 ft higher than the land and moving along the boom horizontally only to load

or unload containers. Figure 25 shows a side view of the crane using a GPS receiver. The GPS-B receiver at

the beam can be used to locate the exact position of the container in a stacked pile of cargo from a distance

(minimum 125 ft). Note that the bottom cell position (xb, yb, zb) can be calculated from the on-ship GPS-A

receiver. It is a variable position due to the fact that the total weight of the on-board containers may be

increased or decreased. The spreader position (xc, yc, zc) is measured by the GPS-B at the bottom of the beam

of the crane. The height of the container relative to the bottom cell can be calculated as

bc zzh −= .

This information can provide to the crane operator as a data-aided helper. This reduces the risk of damaging

the other container, makes it easier for the crane operator to unload or load cargo at any terminal of the port,

thus establishing a more efficient and safer way to handle cargo. This GPS-based automation system with

anti-sway abilities for boom cranes will increase the handling rate especially for inexperienced crane

operators.

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Figure 25. Side View of the crane using GPS Systems.

Beam1 FEU or 2 TEUs

Hoisting Device

Crane Operator Position

Boom

GPS B

125 ft

On-ship GPS A

3.4.1 Auto Steering Technology

The Auto Steering Technology system as shown in Figure 26 is an automated system, a programmable logic

controller (PLC) consisting a group of electronics devices and equipment. The status of the system is

monitored through signals from input devices. The input signals are generated through the continuous

execution of the programs done by the PLC. Finally based on the inputs, the required actions are decided as

out put. Thus the system monitors a crane deviation from its tracks and feeds the data to the crane’s auto-

steering system. Eventually this input is used to decide the position of the container.

Figure 26. Auto Steering Technology.

In order to address the issue of the transportation congestion from the shore to storage area the

concept of Pier Pass and Alameda Corridor was introduced. A short informative description about them is

given in the next Sections.

3.4.2 Pier Pass [11]:

A survey showed that the maximum transportation congestion happens during the peak hours of 0300

to 1800, Mondays through Fridays at the Los Angeles and Long Beach Ports. In order to attend the issue, an

organization owned and operated by the nation’s largest port terminal operators, Pier Pass Inc. came up with

the concept of Pier Pass. According to this plan all international container terminals at the Los Angeles and

Long Beach ports implemented five new shifts per week -- Monday through Thursday nights (6 PM. to 3

AM) and during the daytime on Saturdays (8.00 AM to 6.00 PM). In addition, a Traffic Mitigation Fee was

created, and is required for cargo movement through the ports during peak hours (Monday through Friday,

3:00 a.m. to 6:00 p.m.). The TMF is a congestion pricing mechanism providing an incentive to use the Off-

Peak shifts.

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The fee is $50 per TEU (20-foot equivalent unit) or $100 for all containers larger than a 20-foot unit.

This fee helps in paying for five off-peak shifts. Also the fee motivates the ship owners to make use of the

Off-peak hours when the trip is free of charge.

3.4.3 Success of Pier Pass [11]

As per Chapman University Purchasing Manager’s Survey: December 2006 [12] the number of trips

the truckers make per day has increased to a sizable amount. Statistic report (As of 2006) shows a decent rise

in the number of containers handled. When compared between the two Ports, Port of Los Angeles shows a

higher degree of increase as seen in the Figure 27. Trade activity in the LA basin in the year 2006 showed an

appreciable growth. It created a record of 425,000 inbound containers. Together, both the ports showed 11.6

million TEU’s year-to-date in September 2006 as compared to 14.2 million TEU’s million in all of 2005.

Apart of this, 4500 transportation and warehouse jobs were added by the end of 2006. Reports also prove that

within the first six months of the implementation of the program the two marine terminals shot to between 30

percent and 35 percent of all marine terminal gate activity.

Figure 27. Pier Pass Statistics Report.

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35

3.4.4 Alameda Corridor [14],[15]

Records show The San Pedro Bay ports handles more than 40% of the nation’s total containerization.

Cargo import traffic and 24% of the nation’s total export. It contributed $256 billion in total national trade in

2005 with $62.5 billion of that trade in California. Apart from this, study estimates more than 886,000 jobs in

California as result of the two ports. The taxes are generated from sales, motor vehicle and local tax Revenue.

Thus it was established that the two ports play an important Power- House and job generators for both, the

state and national economies.

It thus became compulsive that goods flow with no congestion in and out of these two areas. In order

to reduce congestion on rail routes on the west coast of America, a project $2.4 billion was invested on a

project called Alameda corridor. The project is a 20mile freight rail expressway owned by the Alameda

Corridor Transportation Authority directly connecting the national rail system near downtown Los Angeles

California to the ports of Los Angeles and Long Beach, running parallel to Alameda Street. The striking

feature of the Alameda street is the fact that it’s an underground triple tracked rail line that stretches 10miles

in length 33 feet deep and 50 feet wide and is shared by two major rail operators, Burlington Northern Santa

Fe (BNSF) and Union Pacific (UP).The corridor has a maximum speed of 40 miles per hour.

Within the first three year of operation, it was noted that the total number of trains using the corridor

increased 12.5%. The number of containers increased nearby 34% from 4117 containers Per day in 2002 to

5514 containers per day in 2004. Statistics also show that the impact on national trade since 1994 grew from

$74 billion to $256 billion due to the implementation of the Alameda project. Thus project proved to be

profitable and showed growth in the number of containers being transported in and out of the San Pedro. The

success of the projects can be clearly seen in the growth in the number of containers handled which is

explained in details in the Section 1.

3.5 Conclusions And Recommendations

Finally, with all the above studies and analysis, the following issues are the strong recommendations

that we come to.

3.5.1 Research on Scheduling and Related Factors

Although the factor of transportation (as seen in Section 3.4) is taken care of by the Pier Pass Plan and

Alameda Corridor, there lies the factors that are needed to be attended. They are:

• The Slack hours of the port when the workers rest.

• Situations when the cranes are stops due to breakdowns.

• Unfavorable weather conditions.

36

• Transfer of the cranes from one operating station to the other.

• Dynamic loading analysis

These factors are yet to be analyzed further to find the proper time schedule and reduce time taken for the

procedures. A fundamental understanding of the existing equipment used in the work place is imperative.

3.5.2 Suggestion to Use GPS Receiver in the Crane

From the above discussion, we conclude that, use of GPS in the loading and unloading procedures

will prove to be a faster and a more convenient way to handle containers. The Anti Sway system of the

containers can arrange the containers in efficiently without too much of maneuvering and is a way less time

consuming. As seen in the Section 3.4, both the anti-sway system and the auto steering system are an efficient

way of handling the containers.

3.5.3 Research in Handing Empty Containers

As seen in the Annual Statistics of both the ports (Section 1.3), it is observed that the Port of Long Beach and

The Port of Los Angeles, handles empty containers which are all most half, or more than half, and some times

more than the number of loaded containers handled by the port. Thus suggestions have been made to further

investigate a better manage the resources used to handle the empty containers, especially the out-bound

operation.

3.5.4 Research in Twin Lift Cranes

The report highlights an advantage of using cranes such as dual hoisting and twin lift capability cranes,

factual information has been provided. Ports may consider these cranes, if applicable.

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4 APPENDIX - TERMINOLOGIES

CITT: Center for International Trade and Transportation.

Berth: A space allotted for a ship to dock or lie at anchor.

FEU: 40 ft equivalent units (L: 40 ft, W: 8 ft, H: 8’6”)

Gantry Crane: A framework spanning a railroad track or tracks for displaying signals, any of various

spanning frameworks, as a bridge like portion of certain cranes

Gangs: A group of persons form a team at terminal for mooring.

ILWU: International Longshoremen's & Warehousemen's Union

Land Bridge: An actual or hypothetical strip of land that connects adjacent continental landmasses and

serves as a route of ships.

Moor: To secure a ship in a particular place as by cables and anchors or by lines .

Moorage: A place for mooring.

PMA: Pacific Maritime Association

Stevedore: A person or company engaged in the loading or unloading of ships.

TEU: 20 ft equivalent units (L: 20 ft, W: 8 ft, H: 8’6”)

5 REFERENCES

[1] http://www.portoflosangeles.org/index.htm [2] http://www.polb.com/about/port_stats/yearly_teus.asp [3] http://www.polb.com [4] http://www.polb.com/facilities/default.asp [5] http://files.asme.org/ASMEORG/Communities/History/Landmarks/5613.pdf [6] http://www.cssc.net.cn/images/10023.jpg [7] http://en.wikipedia.org/wiki/Teu [8] http://en.wikipedia.org/wiki/Crane_(machine)#Floating_crane [9] J. Kogan, Crane Design: Theory And Calculation of Reliability, Pg. 177, Wiley, 1976. [10] J. Kogan, Crane Design: Theory And Calculation of Reliability, Pg. 183 – pg 197, Wiley, 1976.

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[11] http://www.bd ternational.com/news/Pierpass8-05.asppin [12] http://www.transwestern.net/Documents/MarketReports/LA- OCOutlookYear-End2006.pdf [13] http://www.polb.com/facilities [14] http://en.wikipedia.org/wiki/Image:Alameda_Corridor_map.svg [15] http://www.polb.com/civica/filebank/blobdload.asp?BlobID=2145