Cold corrosion creates many new challenges for ship operators.

Patent No. 2910933

While in the past the selection and dosage of the lubricant was based solely on fuel sulphur content it is now necessary to take into account a number of new factors.

To comply with Tier II NOx regulations and the latest Energy Efficiency Design Index (EEDI) guidelines engine manufacturers have changed their engine design. As a result cold corrosion in these engines is more likely to occur due to liner operation temperatures below the acid dew point. To enable effective slow speed operation older engines are modified to optimize “fuel consumption”. These engines now suffer similar problems due to operation at lower temperatures.

Monitoring of the iron content in the cylinder drain oil and the launching of remedial actions in due time can help to avoid cold corrosion and unnecessary abrasive wear in the cylinder liner.

CMT has developed a unique and simple analysis kit to test for and quantify corrosive and abrasive iron especially in the cylinder drain oil.
Together with the CDO BN Test Kit the Electronic Iron Analysis Kit allows to monitor the most important parameters of the cylinder drain oil allowing to optimize the feed rate of the cylinder oil and and at the same time to avoid unnecessary wear of the individual cylinder liner.

The severity of the acid condensation resulting in cold corrosion on the cylinder liner wall is influenced by the following:

• Sulphur content of the fuel
• High pressure in the combustion area
• Liner wall temperature

Although slow steaming has dramatically reduced the problem of abrasive wear it is still a risk factor and needs to be monitored. Most common problems for abrasive wear in cylinder liners are:

• Broken or sticking piston rings.
• Disruption of the cylinders lubricating film caused by water.
• Presence of CAT fines in the injected fuel.
• Residue of calcium ash and carbon from burned cylinder lubricant or incomplete combustion.

Replacement reagents can be ordered on short notice from CMT and come in packs giving the user all he needs to perform the tests. Refill packs are not classified as hazardous for transport. A Test Kit Cleaner is provided for easy cleaning after using the CMT devices. Complete spare cells are available for all tests.