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FAQ: Frequently asked questions

Find answers to common questions about ExxonMobil marine products and technical services. Contact ExxonMobil with any additional questions.


Cold corrosion

Certain engines have shown they are prone to cold corrosion in cylinder liners, caused by the cylinders operating at temperatures below the acid dew point. The SOx present in the cylinder atmosphere dissolves in the water vapour that is condensing on the cylinder liner wall, which creates sulphuric acid and leads to corrosion.

The main engines affected are those designed to comply with the Tier II NOx regulations and the latest Energy Efficiency Design Index (EEDI) guidelines. The issue can be exacerbated by slow steaming operational practices – as well as new engines with higher pressures at low- and part-load – and by using fuels with high sulphur content. Older engine designs that have been modified with fuel optimization kits for low-load and part-load operation to enable effective slow-speed running have also been affected.

Cold corrosion can be counteracted by raising the temperature of the exposed parts of the cylinder liner through modifications to the cylinder liner design and the cooling water system. To prevent the onset of cold corrosion, our MobilGard™ Cylinder Condition Monitoring (CCM) enables cylinder conditions to be closely monitored and cylinder oil feed rates to be optimized accordingly. This helps to enable safe and reliable engine operation and reduce engine wear. In addition, Mobilgard™ 5100 cylinder oil delivers exceptional acid neutralization performance, deposit control and oxidation stability to help mitigate against cold corrosion, optimise feed rates and control costs.

Vessel General Permit

In March 2013, the United States Environment Protection Agency (EPA) issued a revised Vessel General Permit (VGP) that became effective on December 19, 2013, introducing new environmental regulations on vessels operating in US coastal waters. These environmentally acceptable lubricants (EAL) must be used in all oil-to-sea interfaces on any vessel greater than 79 feet. There are also stipulations to maintain seals and equipment to regulation standards, with fines for non-compliance.
The new legislation states that Environmentally Acceptable Lubricants must be biodegradable, minimally toxic and not bioaccumulative, as per the standards defined in Appendix A of the VGP.

In March 2013, the United States Environment Protection Agency (EPA) issued a revised Vessel General Permit (VGP) that became effective on December 19, 2013, introducing new environmental regulations on vessels operating in US coastal waters. These environmentally acceptable lubricants (EAL) must be used in all oil-to-sea interfaces on any vessel greater than 79 feet. There are also stipulations to maintain seals and equipment to regulation standards, with fines for non-compliance.

Mobil SHC™ Aware™ range of high-performance synthetic environmentally acceptable lubricants is specially formulated to provide optimal protection for shipboard equipment affected by the VGP.

Synthetic lubricants

Synthetic lubricants are unique high-performance oils that deliver superior protection and performance when compared to conventional mineral oils.

Buying ExxonMobil marine products

You can check availability and order our lubricants online by using our ports and services guide, which lets you search by location or product across our extensive global port supply network.

Mobil Serv℠ Lubricant Analysis

Mobil Serv℠ Lubricant Analysis is our proprietary used oil analysis service. Visit our Mobil Serv page to find out how to understand your report, sample oil correctly, reset your online password and print labels for oil samples.

Mass Flow Metering System

ExxonMobil’s mass flow metering system (MFMS) is designed to enhance the integrity, security and efficiency of fuel quantity measurement. The technology facilitates the continual and automatic monitoring of direct mass flow, density and temperature. This removes the need for complex conversions using traditional measurement methods and results in enhanced efficiency, complete accuracy and greater transparency of marine fuel measurement and supply.

ExxonMobil is the first organization in the marine industry to adopt a system for mass flow metering approved by a port authority (the Maritime and Port Authority of Singapore) for bunker fuel delivery.

  • mass flow metering system

    Mass flow metering system (MFMS)

    ExxonMobil is the first accredited bunker fuel supplier to introduce a mass flow metering system (MFMS) in Singapore and Hong Kong to enhance the reliability and integrity of fuel quantity measurement.

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    Contact us

    Get in touch with our customer service teams and technical help desk professionals for help with your marine needs.

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