Installation of Becker Mewis Duct

The reduction of operational cost is an important aspect of managing a company especially in a harsh financial environment. In that way companies have the ability of saving financial resources for whatever purpose they want. In the shipping industry, fuel oil consumption is one of the most crucial parameters in defining each year’s budget.

The Becker Mewis Duct (BMD) is a system that can be installed onboard ships making possible to either achieve significant reduction of fuel usage at a given speed or to allow the vessel to move faster for a particular power ratio. The BMD is comprised by fixed elements that are mounted/attached on the ship’s hull. These elements create a duct/nozzle, placed ahead of the propeller along with a fin system mounted within. This has the result of straightening and accelerating the hull’s wake into the propeller, producing also a clear forward thrust.

2014.12.01 - Installation of Becker Mewis Duct Figure 01

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Shaft Jack Up Test

Proper shaft alignment is a key issue on ships, especially on large vessels such as bulk carriers, tankers, container-ships and gas carriers. Any wrong alignment on the shaft can result in undesirable vibrations and higher operating costs. As a result there may be damages in stern tube bearings, propulsion system, M/E and eventually gear box.

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Turbo Charger Overhauling

A turbocharger is a very sensitive equipment onboard a ship and it should be carefully handled. A turbocharger has a turbine on one side and a compressor on other side. Dismantling should start from the compressor side measuring the critical clearance which must be kept between the compressor side end cover mounting face and the compressor side end shaft.

Left side: Air inlet blades – Right side: exhaust outlet blades

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Weld Defects in Ships

A welding structure in order to have the required reliability, during her lifetime, it should have satisfactory quality. This means that it should:

  1. Be designed in a way that is appropriate for its sought use during its forecasting lifetime.
  2. Be manufactured from materials and welding methods according to the requirements.
  3. Be used and maintained rightly.

Welding quality is a relative term and this means that it is not necessary a construction to have better quality from what is needed according to the requirements. When the requirements are strict, that has as consequence the cost of production to be extremely high. On the other hand when the requirements are loose, that has as consequence the cost of maintenance to be high and the forecasting lifetime to be reduced.

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Brief Analysis of Lifeboat Accidents

Lifeboats onboard merchant vessels although designed to save lives during emergencies on occasion they end up taking lives during drills or actual emergencies. The cause of a lifeboat accident can be easily attributed to human mistakes but a more thorough analysis may reveal that other factors may be the actual root cause of the accident. Basically the main causes of lifeboat accidents can be categorized to inadequate design, inadequate maintenance and inadequate training.

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Reliability Theory of Structures

The marine industry can improve its performance in designing systems, subsystems and components on which its operations depend on by using risk-based methods and tools. In an environment of increasingly complex engineering systems and structures, the concern about the operational safety of the latter continues to play an important role in their design, construction and operation procedures. A rational and quantitative approach for assessing the failure probabilities and the impact of failure of the structure on its environment (human beings, natural environment) is needed. [Read more…]