Demurrage

Is the 24 hour Pumping Clause Dead?

WARNING – I have rewritten this post – my original was based on ExxonMobil VOY2012 version 1.0. The latest and only official version of ExxonMobil VOY2012 is version 2.0 dated March 21 2012 which I’ve only just discovered myself. There’s not a great deal of difference between the two but the pumping clause is slightly different.

We are all used to seeing pumping clauses which oblige the vessel to discharge within 24 hours or maintain 100psi. These clauses have been around for as long as I can remember and all follow a familiar theme, i.e. the vessel must do one or the other to protect the Owners demurrage claim. If the vessel discharges within 24 hours then the pumping time counts as laytime or demurrage. If the vessel takes longer than 24 hours to discharge but maintains 100 psi at the manifold then again time counts.

So if the vessel discharges within 24 hours and does not maintain 100psi the Owner is home and dry? Not if you’ve fixed on ExxonMobil VOY2012 as an Owner was telling me at LTOPS earlier this year. His vessel discharged well within 24 hours but Charterers claimed excess pumping based on the wording of Clause 18 which reads:

Owner warrants that Vessel shall discharge entire cargo (be it one or more grades)by maintaining the maximum safe psi pressure at Vessel’s rail that the Vessel can discharge at, but always at a minimum of 100 psi, during the entire period of discharge provided shore facilities permit. All time lost as a result of Vessel being unable to discharge its cargo in accordance with the pumping warranty shall not count as laytime….’

ExxonMobil have dropped the 24 hours part of this clause altogether and it is now a pressure warranty only.

This clause mentions the words ‘maximum safe psi pressure’ and similar wording can be found in other charter parties such as BPVOY4. I can understand this from a charterer’s point of view as I have heard of a case where a vessel was discharging at 100psi with two pumps. The shore requested an increase in pressure but the master refused to start another pump on the basis that he was already meeting the 100psi part of the pumping warranty. Adding words like maximum safe pressure allows the charterers to justify a higher pressure as long as it is safe, but this is the first clause I’ve seen that penalises Owners that discharge a cargo in less than 24 hours.

What if the vessel is pumping at full capacity but there is no shore restriction and therefore there is minimal back pressure – the wording of this clause appears to allow charterers to claim excess pumping even though 100 psi is a physical impossibility.

What do you think of this clause? Have you had arguments over this? Have you got any other pumping clause stories to share? Please add your comments here.

8 thoughts on “Is the 24 hour Pumping Clause Dead?

  1. Phil, This is a well-thought out article. Your question "What if the vessel is pumping at full capacity but there is no shore restriction and therefore there is minimal back pressure?" is certainly valid. The clause says that the vessel must pump "always at a minimum of 100 psi". However, I don't think this means the charterers can invariably claim excess pumping even though 100 psi is a physical impossibility. The clause says "provided shore facilities permit" which would, I hope, be interpreted by a sensible arbitrator to the effect that the vessel cannot be held to be at fault where the shore facilities are so good that they do not provide sufficient backpressure to allow the vessel to reach 100 psi. Nevertheless, there are plenty of borderline cases where it is far from clear whether the vessel or the terminal prevented the vessel's pumps from reaching 100 psi backpressure. It will be interesting to see if this clause creates many new disputes.

    Incidentally, I just happen to be looking at a vessel which discharged a full cargo of 32,600 mt of naphtha in 17.25 hours. The average backpressure achieved at the ship's manifold was only 3 kg/cm2 (42.7 psi). Just as a matter of interest, I used the pumping performance formula to see, how long it would have taken to discharge the cargo at 100 psi. The answer is 11.25 hours – 6 hours less which would indeed have been a physical impossibility. I would like to think that owners would be protected by the phrase "provided shore facilities permit". However, these words have traditionally only been used when the terminal has imposed a restriction on the rate of discharge, not when the facilities are too good!

  2. Hi Roger,

    thanks for your comment. It will be interesting to see how this is interpreted in the future. The example you give of the naphtha cargo shows just how far these arguments could go. The words "provided shore facilities permit' seem to refer to the maximum back pressure and not the maximum flow rate. I agree a sensible arbitrator should be able to work it out, unfortunately despite the history of pumping disputes going back over many years it is not an area that is understood by everyone so I'm not confident we would get the correct answer every time!

  3. Hi Phil

    A cleverly worded pumping clause from a charterers perspective but onerous for an owner. Roger mentions the Asdem pumping performance formula, which I promote whenever I speak about pumping. The formula is by far the best first call 'arbiter' for pumping disputes. I promote it whenever I speak on courses and when delegates see it first hand they want to use it for their pumping disputes, both charterers and owners. Why, because it is fair.

    During one discussion I had about pumping a Master Mariner told me that when a vessel was designed it was kitted out with sufficient pumps and manifolds to enable it to discharge a total cargo wihin 24 hours. But we know that a vessel is rarely, if ever, able to use all manifolds due to lack of sufficient shore facilities. Would this not constitute 'shore restriction?

    I believe the clause will create many new disputes.

  4. Hi David,

    Thanks for your comments.

    I think there has been a case or an arbitration on the lack of hoses argument but I can't recall the details. If the shore don't supply enough hoses it will be a shore resatriction but it should make it easlier for the vesasel to meet 100psi so I guess it won't relieve Owners obligation to meet the back pressure.

    I agree the Asdem pumping formula is a good way of resolving disputes although as Roger has illustrated it could lead to some strange results if other factors are ignored.

    I also agree with your view that this clause will increase the number of pumping disputes unless it is applied with some common sense

  5. Hi Phil, David and Roger,
    These comments are very interesting and I shall certainly be sharing them with my Tanker Chartering students.
    I wonder how many lawyers and arbitrators are aware of these new interpretations in order not to arrive at misinformed awards or judgments ?!

  6. Thanks Jeffrey

    I don't think some of these points are that new but pumping generally is one of those areas where unless one understands what happens in practice and the physical laws that apply it could lead to some odd conclusions.

    Let's see how the next dispute is resolved in court or arbitration….

  7. Hi Phil,
    It it indeed not nice to see that one of the cornerstones of tanker charter parties, that of 24 hrs OR 100 psi, is no longer there in ExxonMobil Voy2012. It is common practice to maximize the discharge rate to satisfy the receivers but to see that this now an obligation is something different.
    Regarding the irregularities of applying the ASDEM formula and if applying the ASDEM formula can be accepted in the court, I could elaborate further. If anybody wishes to know how, please take my e-mail address and I will send you a recently published work.

  8. Returning to this issue, I would like to add that the wording in BPVoy4 19.9 has the additional description 'pursuant to a restriction imposed by the terminal or arising from physical attributes of the terminal'. This will allow the owner to defend the cases where the terminal is too good that the back pressure will be very low.

    In case of low back pressure a VLCC (or any other vessel) must discharge her cargo is 24 hrs.
    A tanker therefore loaded with 330,000 m3 (280,000 mt of Ar.L) must achieve a rate of 330,000/24 = 13,750 m3/hr.

    VLCCs are equipped with 3 cargo pumps with following characteristics:
    5,000 (or max 5,500) m3/hr at 150 m total head at max RPM.

    This means that one pump working alone discharging crude oil from a number of cargo tanks can achieve a flow rate of 5,000 m3 provided the total head is 180 m.
    (Total head of 180 m means that the pressure at the manifold is about 12 kgrs/cm2).

    What must become clear however is that adding a second pump in parallel (e.g. having two pumps discharing cargo to a common shore tank) does not double the pumping rate. The increase in the rate by adding a second pump is only a fraction of the rate by having one pump only. Adding a third pump will have an even smaller effect. The reason for that is that the pumps always work at the point where the head supplied by the pump is equal to the head demanded by the pumping system (like supply and demand curves in economics).

    The pump rate will be doubled by adding a second pump only if the second pump works independently, which means that each pump is connected to its segregation of tanks only and discharges to a separate shore tank via a separate shore line.
    Otherwise a tanker cannot achieve the required rate of 13,750 m3/hr, and that would be due to 'physical attributes of the terminal' according to BPVoy4.

    I think that it is time that these issues start to appear in defence on pumping disputes.

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