1. A proposed test programme should be submitted
prior to the testing.
2. During testing of continuous bollard pull (BP)
the main engine(s) should be run at the manufacturer's recommended
maximum torque according to maximum continuous rating. Verification
of the actual output should be requested during the test.
3. During testing of overload pull, the main engine(s)
should be run at the manufacturer's recommended maximum rating that
can be maintained for minimum 30 minutes.
The overload test may be omitted.
4. The propeller(s) fitted when performing the
test should be the propeller(s) used when the vessel is in normal
operation.
5. All auxiliary equipment such as pumps, generators
and other equipment which are driven from the main engine(s) or propeller
shaft(s) in normal operation of the vessel should be connected during
the test.
6. The length of the towline should not be less
than 300 metres, measured between the stern of the vessel and the
test bollard. A minimum length of twice the vessel length might be
accepted.
7. The water depth at the test location should
not be less than 20 metres within a radius of 100 metres of the vessel.
If the water depth of 20 metres cannot be obtained at the test location,
then a minimum water depth which is equal to twice the maximum draft
of the vessel may be accepted. It should be noted that reduced water
depth may adversely affect the test results.
8. The test should be carried out with the vessel's
displacement corresponding to full ballast and half fuel capacity.
9. The vessel should be trimmed at even keel or
at a trim by stern not exceeding 2% of the vessel's length.
10. The vessel should be able to maintain a fixed
course for not less than 10 minutes while pulling as specified in
items 2. or 3. above. Certified continuous bollard pull is the average
reading of the 10 minutes period.
11. The test should be performed with a wind speed
not exceeding 5 m/sec.
12. The current at the test location should not
exceed 0.5 m/sec. in any direction.
13. The load cell used for the test should be
approved by a competent body and be accurate within +/- 2% within
the range of loads to be measured and for the environmental conditions
experienced during the test.
14. An instrument giving a continuous read-out
and also a recording instrument recording the bollard pull graphically
as a function of time should both be connected to the load cell. The
instruments should if possible be placed and monitored ashore.
15. The load cell should be fitted between the
eye of the towline and the bollard.
16. The figure certified as the vessel's continuous
bollard pull shall be the towing force recorded as being maintained
without any tendency to decline for a duration of not less than 10
minutes.
17. Certification of bollard pull figures recorded
when running the engine(s) at overload, reduced RPM or with a reduced
number of main engines or propellers operating can be given and noted
on the certificate.
18. A communication system shall be established
between the vessel and the person(s) monitoring the load cell and
the recording instrument ashore, by means of VHF or telephone connection,
for the duration of the test.