Q1: Are MFM a recent technology? Has it been tried and tested?
A: The MFM is not a recent technology. The First Industrial Patent for the MFM dates back to the 1950s and the first
meter was manufactured in 1970s. Today it’s widely used in industries such as the Oil & Gas, Chemical, Life Sciences,
F&B etc. American Petroleum Institute (API) has approved the use of MFM for custody transfer in 2002. (API MPMS
5.6 Coriolis flowmeters)
Q2: How does MFM measures mass directly?
A: The MFM operates on the Coriolis principle which measures the oscillation frequency (ie: twisting) of the measuring
tubes in the meter. The sensors, at the inlet and outlet ends, register the resultant phase shift in the tube’s oscillation
geometry and compute the rate of mass flow.
Q3: Why has it taken so long for bunker quantity measurements to adopt metering while automobile fuels retailers
has adopted metering for some time?
A: The use of MFM for bunkering is not a “plug & play” system. From our experience in the test bedding programme,
we learnt that the piping configuration on each bunker tanker might vary. A proper set-up, including the piping
configurations, is crucial to ensure the optimal performance of the entire MFM system.
In 2009, MPA and SPRING Singapore jointly initiated a MFM Working Group (WG) to develop and validate the use of
MFM for bunkering. Since 2011, MPA and the WG had conducted extensive trials to ensure that the system is suitable
for Singapore’s bunkering environment. With the success of the trials, MPA had, in June 2012, approved the first
MFM for official custody transfer in the Port of Singapore. The first MFM was an Emerson’s meter. In Oct 2013, MPA
approved an MFM produced by Endress & Hauser for use in the port of Singapore.
It is important to note that the approval for custody transfer is not a system-type approval. All individual MFM
systems need to undergo and pass the physical acceptance test before approval is granted by MPA.
Q4: When will the delivery procedures by MFM be incorporated into SS600?
A: The WG is currently developing a Technical Reference (TR) which will eventually be developed into a Singapore
Standards (SS).
In the interim, the Singapore Standard Code of Practice for Bunkering (SS600) is being revised and will incorporate the
use of MFM for bunker deliveries. The revised SS600 (SS600:2014) will be launched at SIBCON 2014. All MFM
deliveries will have to adhere to the MPA- approved bunker tanker specific procedures. MPA has also published a
Generic Mass Flow Metering (MFM) delivery procedure for the industry as a guide for the bunkering stakeholders
Q5: What are the 3rd party certifications or audits that MFM installations are subjected to?
A: MFMs are calibrated in accordance to SPRING Singapore’s requirement. The requirements are in line with both
OIML R117 and ISO 17025 standards. All MFM systems onboard bunker tankers are to be evaluated and approved by
MPA, before they are allowed to be used for custody transfer of bunkers.
Q6: How reliable is the MFM system and are there any contingency plans when the system breaks down?
A: There are minimal moving parts in the system and MFMs have been reliably employed in other applications. MFM
systems are also equipped with an uninterrupted power source (UPS) that is able to run the system in the event of a
power failure.
In the unlikely event that the MFM stopped in the middle of a bunkering operation, pumping shall be stopped
immediately and the meter’s totalizer readings shall be recorded. Tank gauging, in accordance with SS 600, shall be
used to determine the remaining quantity to be delivered and a separate BDN shall be issued. The final quantity
delivered shall be the sum determined from the meter readings and the tank gauging recorded in the respective BDNs.
This procedure is covered under the Generic Generic Mass Flow Metering (MFM) delivery procedure that is available
Q7: Incentive eligibility
A: MPA has an incentive scheme to assist the industry in defraying a portion of the cost of MFM adoption. MPA will
be making a lump sum payment of $80,000 for all existing bunker tankers (holding a valid SB Harbour Craft (bunker
tanker) licence) delivering MFO in the port, upon the final approval for MFM to be used for custody transfer for
each bunker tanker.
Q8: I have a new bunker tanker which is estimated to be delivered between now and 31 Dec 2014. Do I qualify
for the incentive?
A: New bunker tankers will not be eligible for the incentive. For new bunker tankers that are being registered
between now till 31 Dec 2014, it is advisable to install the MFM system as soon as possible. The bunker tanker will
be scheduled for the acceptance test to be conducted by MPA. The bunker tanker will not be allowed to deliver
MFO after 1 Jan 2017.
Q9: What is the approval process for MFM system and what is the downtime expected?
A: The approval for MFM is an 8-step process (Annex A) covering from system procurement until the final approval
for custody transfer. The entire process is estimated to take around 4 months. However, the downtime for the
bunker tanker is approximately 1.5 weeks.
(Installation: 1 week, acceptance test: 3 days)
MPA will be scheduling existing bunker tankers for the acceptance test. This will be done approximately 2 weeks
after the deadline of the docking of the bunker tankers. With this arrangement, the downtime of the bunker
tankers will be minimised.
Q10: What happens when there is a difference between the reading of MFM and the terminal delivered figure
during loading?
A: All custody transfer meters used in terminals are required to follow the requirements as stipulated by SPRING
Singapore. SPRING Singapore’s requirement for the MFM is similar.
Our trial results showed that the variance between the MFM reading and the terminal delivered figure are within
the industry acceptable standard of 0.5%. In addition, there is no change from the current arrangement and
procedures when bunker tankers load from terminals. In the event of a bunker quantity dispute, the bunker tanker
should raise a note of protest as per current practice. In such situation, the bunker tanker will be able to
understand the loading operation in greater details through the recorded data.
Q11: How often will calibration be done and how is it done?
A: SPRING Singapore requires calibration procedures to comply with international standards OIML R117 and ISO
17025. The current requirement is for the meter to be calibrated every 3 years. Unlike traditional geared meters,
MFM does not have mechanical parts or moving parts and therefore the need for re-calibration is relatively lower.
The current approved meters were evaluated and are still performing in good condition.
Under the current practice, the MFM is required to be sent to a SPRING Singapore’s Recognised Testing Laboratory
(RTL) for re-verification/re-calibration. The bunker craft operator should time such operation to coincide with its
docking schedule to reduce the downtime for the bunker tanker.
Q12: Will my bunker tanker still be allowed to perform delivery via sounding (SS600) once the MFM system is
approved for use by the bunker tanker??
A: The mandatory use of MFM for MFO delivery is 1 Jan 2017. Once MPA approves the MFM system for custody
transfer for the bunker tanker, the approved MFM system should be used as the default measuring equipment for
bunker transfer/deliveries. In the event, there is a contractual agreement, between buyers and sellers, to use SS600
procedures (sounding) to measure the quantity of bunkers, MPA will not object to the arrangement. However, the
MFM system shall be kept operational during all operations and the information recorded on the MFM system will
be used in bunker dispute investigations.
Q13: How will the cost of bunker be affected by the implementation of MFM?
calculated the monetary impact to bunker supplier and bunker craft operator using the cost of the MFM
system as a base. The calculations did not consider the gain in efficiency enjoyed by the bunker craft operator with
the expected bunker tanker’s higher turnaround rate.
Estimated cost of MFM inclusive of
(Estimated cost of $300,000 - $80,000*)
Estimated yearly maintenance cost
inclusive of calibrations
Period of amortization
Average tanker capacity
Average number of turns per
Bunker delivered per month
Unit cost for MFM
5 years
32,000 mt
*MPA incentive of $80,000 to existing bunker tankers delivering MFO
Q14: How is the testing of MFM system conducted?
A: Since 2011, MPA and the Working Group had conducted extensive trials on the MFM at varying operating
conditions to ensure that the system is suitable for Singapore’s bunkering environment. A total of 17 bunker
tankers participated in the test-bedding programme.
All meters approved for custody transfer meets the recommendations set by the Organisation of Legal Metrology
(OIML)’s R117:2007 standard - an international recommendation for measuring system for liquids other than water.
The meters are then sent to a SPRING Singapore’s Recognised Testing Laboratory (RTL) for calibration before it is
installed on the bunker tanker. Once fitted onboard and sealed, all MFM systems have to undergo 3 rounds of test.
During the tests, the entire delivery system are put through the verification process to ensure all pass-by are
blanked out and sealed. Sealings are to be done by an independent party to ensure the integrity of the system. The
data collected during the test were sent to Singapore’s National Metrology Centre for validation.
Q15: How do I ensure the integrity of MFM system is not compromised?
A: MPA requires the meter system set up to have no by-pass of flow after the meter. Any pass-by system on bunker
tankers shall be blanked out and sealed.
Under the approved delivery procedure, opening and closing procedures for a bunker delivery differ slightly All
bunker tankers installed with the MPA-approved MFM are to maintain the latest seal verification report and
metering system diagram indicating all the sealing points. The vessel representative and bunker surveyor, if
engaged, are required to check and ensure all listed seals are intact. They shall sign on the Mass Flow Metering
System Seal Checklist to indicate that the seals are intact. The same should be done be done for the closing
Other than the Mass Flow Metering System Seal Checklist, the Meter Reading Record Form and Bunker Metering
Ticket generated by the system will provide an additional layer of security. All these requirements are stated in the
Generic Mass Flow Metering (MFM) delivery procedure.
Q16: How will transparency be enhanced when compared to tank sounding?
A: There is continuous digital data captured during the delivery process, the data can be viewed in the form of a
delivery profile. At any instance in time, and we are able to trace the amount of mass transferred. The MFM system
is also able to detect changes in operating conditions e.g. when we change supply tank, or when we clear the lines
at the end of the delivery.
The delivery profile data can be extracted from the system, if required.
Q17: Is there still a need for bunker surveyors for deliveries done via the mass-flow meters?
A: Yes. The role of bunker surveyor being an independent party to witness and ensure compliance to bunker
delivery processes remains unchanged.
There is a change in the function of bunker surveyors for MFM deliveries. For example, the surveyor is required to
cross check the seal verification report and the actual physical seals at various locations in the MFM system. This
procedure is to ensure the integrity of the entire MFM before and after the delivery. The detailed actions required
from bunker surveyors are covered under the Generic MFM delivery procedure.
MPA is also looking to expand the scope of work for surveyor and exploring the possibilities to train bunker
surveyor to perform zero verification for approved MFM system.
Q18: Will there be training provided to ensure bunker surveyors have the competency on MFM delivery?
A: Yes. MPA is currently working with various organisations to conduct technical workshops, pre-conference
symposium and bunker surveyor refresher courses to ensure bunker surveyors attain the competency to handle
MFM delivery. We will be contacting accredited bunker surveying firms to share further details.
Q19: If it’s required by the owner/charterer to perform opening/closing using sounding method. Will MPA allow
A: For a bunker delivery done via a MPA- approved MFM system, there is no need for sounding to be conducted. The
BDN will reflect the delivered amount as registered on the MFM system. In the event there is a contractual
agreement between the bunker buyer and bunker supplier to conduct a bunker delivery as per SS600 procedures,
MPA will not object to such arrangement before 1 Jan 2017. However the appointed cargo officer and bunker
surveyor shall ensure that the MFM system is kept operational during all operations.
Documents available on MPA website
Generic Mass Flow Metering (MFM) delivery procedure
Annex A
Certification stages
Endorsing Party
1. Sizing of MFM
(correct operating range)
Procurement of MFM system
2. Registration with MPA for incentive
scheme, if eligible
(Submission of Purchase order)
Arrival of MFM system
SPRING Singapore’s approval
Installation of MFM system
MFM System Commissioning
Official Acceptance test of
MFM system
Data Verification of test
result by National Metrology
Submission of documents to
MPA for approval
1. Complete water calibration
2. Submission of all required documents to
SPRING Singapore
1. Level 1 & 2 approval
1. Installation
2. Development of sealing plan
1. Submission of class endorsed revised
piping diagram and proposed seals location
for endorsement by MPA
2. Submission of bunker tanker specific MFM
delivery procedure
(to refer to generic MFM delivery procedure)
3. Submission of MFM vendor and BCO’s
attestation on system & crew readiness for
acceptance test
4. Completion of sealing by SPRING
Singapore & Authorised Verifier/ authorised
1. 3 runs of test
(3 x loadings and 3 x deliveries with MPA
chartered bunker tanker.
Test date is scheduled by MPA
SPRING Singapore
Data collection
supervisor, test
(approximately 2 weeks after deadline of docking)
1. Submission of test data and test
1. Submission of all relevant documents*
2. Lump sum incentive payment, if
*list of documents required for application
Meter Certification
Water Calibration Certification
SPRING Singapore certification of verification
Water to Bunker conversion attestation
Mass Flow Metering system (Design, layout, configuration etc)
Endorsed Sealing plan and bunker tanker piping diagram
Latest Seal verification report
Zero verification procedure
All Zero verification reports
Endorsed MFM delivery procedure specific to the bunker tanker