Feature Articles

At some time in his career the Diagnostic Engineer may well have to examine the running of a compression ignition engine. Many of the defects that occur on such units are down to wear in the main bearings causing the crankshaft to change its longitudinal straightness. Usually the first diagnostic test on such an engine is to take a series of measurements between the crank webs at various points round the circle of rotation called somewhat in correctly crankshaft deflections. If a driving engine is of the compression ignition type with a cylinder bore above about 250 mm (10 inches), it is also necessary to consider the alignment of its crankshaft. Below that size, the overall stiffness and small size of the unit and the fact that the crankshaft itself is an integral forging make the measurement of crankshaft deflections both extremely difficult and unnecessary.

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Feature article prepared by the Research & Development Department, Hempel A/S, February 2016 (Original paper published in 2008)

Traditional fouling release coatings consist of a silicone elastomer (PDMS) and rely on a low surface tension (hydrophobic) and a low modulus of elasticity, usually with a good initial foul free performance. With time, the coatings ability to self-clean is lowered, which results in a higher hull skin friction. The invention behind the 3rd generation fouling release coatings is a unique blend of silicone polymers that has and maintains a more hydrophilic surface, with fouling release performance that lasts. The foul free period is longer, and required speed for self-cleaning is lower. This results in a lower hull skin friction over time with potentially lower fuel consumption.

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We were lucky when we were struck by lightning on our small 35’ GRP cruising sailing boat in Turkey in 2013, but without an LPS. All the plastic and some of the metal gear at the top of the mast exploded (see photo below) and simultaneously the headlining in the saloon exploded downwards with a loud bang. So much smoke that we initially thought we were on fire; but my wife and I survived unscathed to tell the tale.

The most likely discharge exit was through the propeller shaft, but practically all electronics were violently destroyed and, as an electrical and electronic engineer, my assessment for our insurance claim afterwards showed that most devices had experienced severe arcing with small electronic components having exploded internally (see photo below).

Continue reading “An approach to a modern sailboat lightning protection system”

We are haemorrhaging money! Machinery is the biggest cost in terms of overall claims amount that insurers pay. Machinery incidents amount to over 40% of the overall claims paid by underwriters. To give some background, insurers cover the cost of replacing machinery which has broken as a result of negligence by the crew providing such loss or damage has not resulted from want of due diligence by the
insured, owners or managers. This is very wide coverage and effectively acts as warranty insurance for the machinery. Obviously it is open to abuse and insurers trust the owners to be open and honest when presenting a claim for machinery damage.

I have been in the insurance industry for over 30 years and have benefited from the Braemar’s, previously the Salvage Association, monthly reports. The top four causes of casualty are always machinery, grounding, fire and collision in that order. This is also backed up by the International Union of Marine Insurers (IUMI), where the data is kindly provided by Lloyd’s List Intelligence.

Continue reading “Machinery, what is the underwriter’s problem?”