Port Performance
I. BERTH PERFORMANCE INDICATORS
Calculate what?
-
Ships waiting time
Ships time in port
Their usage?
-
To utilize berths in the port
To avoid delays to the ship
To optimize port capital and resource
Main berth performance indicators:
1. Berth Throughput (BT)
2. Waiting Time (WT)
3. Service Time (ST)
4. Time in Port
5. Grade of Waiting (GW)
6. Berth Occupancy Ratio
7. Berth Working Time Ratio
(1) Berth Throughput:
BT = Total units handled in a period of time (usually a year)
RO-RO berths: BT= Total vehicles (cars, trailers/ trucks) or rolls/ year on the berth concerned
Container berths: BT= Total TEU/ year on the berth concerned
Bulk or general cargo berths: BT= Total tonnes/ year on the berth concerned
(2) Waiting Time:
The time a ship waiting for an available berth.
The delay between a ships arrival in the port and its tying up at the berth.
Waiting Ratio=
Time waiting for a berth
Service Time
Service time is the time the ship stays at the berth whether it works or not.
Task: In Nov 23rd 2005, a container ship arrived at Amsterdam Port to load the cargo. At 9:00
am, the ship arrived at the port. However, all adequate service points had been occupied so the
ship had to wait for an available berth until 5:00 am on the next day and then started loading. It
finished loading work at 6:00 am in Nov 26th and was allowed to leave the berth 1hour later.
Question: Determine Waiting Ratio for the ship, assuming that Amsterdam Port operates 24
hours a day.
Solution:
Waiting time (9:00 am of Nov 23rd - 5:00 am of Nov 24th): WT = 20 hrs
Service time (5:00 am of Nov 24th 7:00 am of Nov 26th): ST = 50 hrs
20
Waiting Ratio 50 =0.4
(3) Service Time:
The time a ship staying at a berth whether it is working or not.
From the first line to ashore to the time the last line is let go.
( Average) Service Time Ratio=
Cumulated Service Time
Total Number of Ships
Task:
There are two incoming ships A and B to Berth no.1 for discharging cargo. Ship A is served at
the berth as soon as it arrives at the port at 1 p.m. with handling time of 10 hrs. Ship B arrives at
the port at 2 p.m. with 4 hrs handling. Two ships leave the berth right after finishing their
discharging.
Question: Determine Service Time Ratio for Berth no.1, assuming that the length of Berth no.1 is
not long enough to serve two ships at one time and the port operates 24hrs a day.
Solution:
ST of Ship A = 10 hrs
ST of Ship B = 4 hrs
Service Time Ratio
10+ 4
=7 (hrs )
2
(4) Time in Port/ Turnaround time:
2
The total time the ship spends in the port from arrival at the port to final departure
( Average ) Turnaround Ratio=
Cumulated WT + ST
Total Number of Ships
Task:
There are two incoming ships A and B to Berth no.1 for discharging cargo. Ship A is served at
the berth as soon as it arrives at the port at 1 p.m. with handling time of 10 hrs. Ship B arrives at
the port at 2 p.m. with 4 hrs handling. Two ships leave the berth right after finishing their
discharging.
Question: Determine Turnaround Time Ratio for Berth no.1, assuming that the berth is not long
enough to serve two ships at one time and the port operates 24 hours a day.
Solution:
Ship A: WTA + STA = 0 + 10 = 10 (hrs)
Ship B: WTB + STB = 9 + 4 = 13 (hrs)
Turnaround Ratio
10+13
=11.5(hrs )
2
(5) Grade of Waiting:
The comparison of the waiting time with the service time
GW Ratio=
Cumulated Waiting Time
Cumulated Service Time
10% is acceptable
Lower is better
Task: In 2000, Port X has cumulated Service Time and cumulated Waiting Time as 8,000 and
1,750 hrs respectively.
Question:
a)
Determine Grade of Waiting Ratio for Port X
b)
Evaluate the quality of Port X
Solution:
a)
GW Ratio=
1,750
0.219 21.9
8,000
3
b) Port X is considered as an inefficient one with GW rate of 21.9%
(6) Berth Occupancy Ratio:
Berth Occupancy Ratio shows the level of demand for port services
Berth Occupancy Ratio=
Total Service Time
Hours aYear
Hours in a Year: 8,760
Task: In 2007, the total number of hours Berth X occupied was 7,500 hrs.
Question: Determine Berth Occupancy Ratio for Berth X in 2007
Solution:
Berth Occupancy Ratio=
7,500
0.856
8,760
85.6%
(7) Berth Working Time Ratio:
The number of hours during which a ship is worked in port during the Total Service time on the
berth
Relating to the quality of services to ships
Reasons for the idle time?
Berth WorkingTime Ratio=
Total Time Worked
Total Service Time
Task:
A vessel arrived at the berth at 4 a.m. and started unloading the cargo. Because of the rainfall
from 7 a.m. to 10 a.m., the vessel had to stop temporarily and then continued working. At 2 p.m.,
the unloading crane was broken down and spent 1.5 hrs to repair. The vessel finished unloading
at 5 p.m. on the same day.
Question: Determine Berth Working Time Ratio
Solution:
Total Service Time (4 a.m. 5 p.m.) = 13 (hrs)
Total Time Worked = 13 3 1.5 = 8.5 (hrs)
Berth Working Time Ratio=
8.5
0.65
13
65%
II. HANDLING OPERATION INDICATORS
4
Three Input resources for handling operations
-
Ship/ Shore Handling Equipment
Yard Transfer Equipment
Labor Force
(1) Ship Output- SO:
-
The rate at which the cargo is handled to and from a vessel
Showing how good the cargo handling operations are
Three Ship Output indicators:
Working Ship Output (WSO)
Berth Ship Output (BSO)
Port Ship Output (PSO)
Total tonnagehandled
Total hours port
Total tonnagehandled
Total hours worked
Total tonnagehandled
Total hours on berth
Task:
In the first week of January ship arrived at the port at 5 a.m., waited for a free berth until 7 a.m.
and then started loading the cargo. The crane was broken down from 9:30 a.m. - 1:30 p.m. After
loading totally 1,350 tonnes of the cargo, the ship was let go at 5 p.m. on the same day.
Question:
a) Determine Port Ship Output
b) Determine Berth Ship Output
c) Determine Working Ship Output
Solution:
Total tonnage handled = 1,350 tonnes
Total hours in port (5 a.m. - 5 p.m.) = 12 hrs
Total hours on berth = 12- 2 = 10 hrs
Total hours worked = 10 4 = 6 hrs
Port SO =
Berth SO =
1,350
12
1,350
10
= 112.5 tonnes/hr
= 135 tonnes/hr
Working SO =
1,350
6
= 225 tonnes/hr
(2) Gang Output- GO:
What does gang mean?
Tonnage handled
Average Output/Gang/Hour Total gang x hours worked
Average Number of Gangs/Ship
Total number of gangs
Number of ships
Task: The table shows the gangs used to handle the cargo in Port no.1 on the same day with the
following information:
Number of Gangs
Ship
Working hours
Tonnage handled
02
16
1,200
04
10
1,500
03
12
2,000
Question: Determine Average Output/Gang/Hour and Average Number of Gangs/Ship?
Solution:
Average Gang Output =
1,200+1,500+2,000
2 x 16+ 4 x 10+3 x 12
Average Number of Gangs/Ship =
9
3
= 43.5 (tonnes/gang/hr)
= 3 (gangs)
(3) Utilization Ratios:
The effectiveness of resource utilization
Number of worked hours
Rate of Utilization of Cranes Number of available hours
Number of man hours worked
Rate of Utilization of Workers Number of man hours available
Task: Calculate Utilization Rate of the crane in Port X, assuming that its total available time for
use is 147 hrs/week and the time it actually operates to handle the cargo is 86 hrs/week.
Solution:
Rate of Utilization of Crane =
86
147
= 0.59 = 59%
III. STORAGE OPERATION INDICATORS
Average Dwell Time:
Dwell Time is the time that the cargo stays in the port (yard/ shed/ CFS).
Dwell Time determines the space required.
Average DT =
Total Tonnage x dwell time
Total Tonnage stored per day
Task:
Containerized Cargo
TEU
Dwell time at CFS (days)
20
35
30
10
Question: Determine Average Dwell Time
Average DT =
20 x 6+35 x 3+30 x 10
20+35+30
= 6.2 days
IV. QUALITY OF SERVICE INDICATORS
(1) Working Hours Ratio:
The co-ordination of all administrative and operational port service
Need to reach a simultaneous working schedule for all services and departments.
Working Hours Ratio =
Number of noncoordinated hours
24 hrs
Task: Fill the blanks:
Service
Opening hours
Non-coordinated hours
Tugs/ pilots
06:00 22:00
Handling
00:00 24:00
Customs clearance
08:00 18:00
Delivery/ receipt
06:00 20:00
Port office
07:00 17:00
Total
Working hour Ratio
Solution:
Service
Opening hours
Non-coordinated hours
Tugs/ pilots
06:00 22:00
08 hrs
Handling
00:00 24:00
0 hr
Customs clearance
08:00 18:00
14 hrs
Delivery/ receipt
06:00 20:00
10 hrs
Port office
07:00 17:00
12 hrs
Total
46 hrs
Working hour Ratio
= 46/24
(2) Punctuality Ratio:
The ports ability to respect the forecasted times and schedules as plan
The ratio is the difference between planned and actual arrival and departure times and the
number of ship calls made.
Punctuality Ratio =
Total
delayed
Number of ship calls
Task: During the first month of 2013, U.S. Port had 75 ship calls. Total delayed times of these
calls is 10.
Question: Determine Punctuality Ratio
Solution:
10
75
Punctuality Ratio =
= 13.3%
(3) Reliability Ratio:
Popular factors affecting the reliability of a port?
Reliability Ratio =
Number of effective days worked
Number of scheduled working days
Task:
In 2005, Port X has total scheduled working days of 350 days. Because of 2 strikes lasting for 28
days and 10 days respectively, Port X had to stop working temporarily.
Question: Determine Reliability Ratio of Port X
Solution:
Reliability Ratio =
350 (28+10)
350
= 89%
V. BERTH CAPACITY
Annual Maximum Berth Capacity:
1.
Tonnes/ship-worked hr = tonnes/gang-worked hr x average number of gangs/ship
2.
Tonnes/service hour = tonnes/ship-worked hour x worked hour/service time
3.
Annual Max Berth Capacity
= tonnes/service hour x 24 hours x 365days x maximum occupancy ratio x number of berths
Cargo-type and packing methods influence a berths capacity:
Type of packing
Gang output (tonnes/gang-hour)
Cases and boxes
12-15
Bags
20-25
Pre-slung bags
40-50
Pallets
25-40
Containerized cargo:
Gantry crane
200-250
Ship crane
120-150
RO RO
300-500
Dry bulk
1,000
Task:
In Port X, there are 6 berths in the general cargo terminal with the followings:
Tons/gang/worked hour: 20 tonnes;
Number of gangs/Ship: 3 gangs;
Worked time/Service time: 60%;
Maximum berth occupancy ratio: 74%
Question: Calculate the maximum capacity of the terminal for general cargo
Solution:
Tonnes/Ship/worked hour = 20 x 3 = 60 tonnes
Tonnes/Service hour = 60 x 0.6 = 36 tonnes
Annual Maximum Berth Capacity = 36 x 24 x 365 x 0.74 x 6 = 1,400,198.4 tonnes for the 6
berth terminal
VI. STORAGE CAPACITY
Storage Capacity:
Storage Capacity =
tons throughput / year x Stowage Factor x dwell time
365
What is Dwell time?
What is Stowage Factor?
Task: In 2012, Port X throughput is 2,000,000 tons. Total Dwell time of the cargo is 100 days.
Stowage Factor of the cargo in Port X is 1.6m3/ton.
10
Question: Calculate the Storage Capacity of Port X
Solution:
Storage Capacity =
2,000,000 x 100 x 1.6
365
= 876,712 tonnes
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