The introduction and mandating use of mass flow meters is widely considered to have enhanced transparency and have managed manipulations on delivery quantity, such as the “cappuccino” bunker effect.
However, for some time now there have been talks in the market about whether the MFM readings could be manipulated with the use of magnets. In this regards, Petro Inspect says that during a recent bunker survey on board an established bunker supplier’s barge in Singapore, one of the surveyors caught the use of a powerful magnet. This seems to be the first public evidence of such manipulation.
Founder of Petro Inspect, Kaivan H. Chinoy, said that since the company had heard about such potential malpractices, they took the initiate to contact MFM manufacturers in order to get further advice about the effects that the magnet could have on the MFM. The industry leader, Siemens Coriolis Flow Meter advised that a magnet could potentially have an effect on the MFM’s performance, depending mainly on the power of the magnet and where same was placed.
According to Siemens, strong magnets should be placed where the pickup sensors are located and remain in that position for some period of time in order for the meter’s reading to be affected. Furthermore, Siemens said that a flow meter which is exposed in such a magnetic field may give inaccurate results even after the magnet is removed and in this case re-calibration will be necessary.
Another interesting point raised by Siemens is that the Coriolis Flow Meter largely consists of non-magnetic material and therefore in order for a magnet to be attached on a MFM, an other material such as a tape should be used. Indeed, Petro Inspect says that in this case the magnet was attached on the MFM with a tape. Furthermore, according to Petro Inspect, evidence has been found that tapes were used in previous cases to attach unknown items on MFMs of other barges.
Petro Inspect explains that in this case there was not any evidence neither that there was theft on delivered quantity, nor that the magnet met the requirements to interfere with the MFM readings. However, “bunker buyers should now be on the lookout for such a malpractice” Chinoy concluded.