Text 9 An Introduction to Ship’s Turbine Generator

Turbine generator is a popular source of clean power generation on ships as they don’t use any type of fuel i.e. heavy or diesel oil. Steam is used for power production in case of turbine generators. Steam is an easy, environmental friendly and cheap form of fuel on ships. For turbine generators, the steam comes from the ship’s steam boiler plant.

In turbine generator, steam is used with high pressure to rotate turbine wherein the thermal energy of the steam gets converted into rotary motion. The turbine is connected to the alternator’s rotor; hence the rotary notion of the turbine is utilized to generate electric power.

Alternate Uses of Steam Turbine

On ships, the steam turbine can also be used as a direct propulsion plant, in which, the turbine shaft is connected to propeller shaft of the ship. Since the speed will be in thousand rpm, reduction gears and reduction systems are used to get a drop in propeller rpm.

The propelling plant of the ship can be driven by steam turbine through a slow speed motor. The turbine generator directly supplies power to these slow speed motors which are connected to the propeller shaft of the ship.

Understanding the Construction of Turbine Generator system:

Turbine Prime Mover

A turbine will act as a prime mover in turbo generator and is fitted on the same shaft as of the alternator’s rotor.

Alternator

The alternator is used to convert the rotary motion of the turbine to electrical energy and its output is supplied to the main switch board of the ship.

Steam Control Governor

The governor is used to control the speed of the turbine generator during starting, normal operation and shutting down. It controls the quantity of the steam inlet to the turbine generator.

Steam Control Valve

Different pressure control valves are fitted in the steam line and are controlled using governor for the flow of steam from the ship’s boiler system.

Condensate pump

The condensed steam, after the turbine is further cooled down, is pumped back to the cascade tank by condensate pump.

Vacuum pump for glands

The steam turbine shaft is provided with glands wherein steam is sprayed at a pressure of 0.3~ 0.5 bar so that the vacuum inside the turbine casing doesn’t drop.

Condenser

The heat exchanger acts as a condenser to cool down and condense all the steam from the turbine into water so that it can be pumped back to the hot well.

Vacuum pump header tank

A vacuum pump header tank is provided to cool down the vacuum pump as the later deals with high temperature steam.

Text 10 Coronav: High-Definition Corrosion Control

How can corrosion be detected on the most inaccessible parts of a ship, such as the outer painted hull, decks concealed by thick surface treatments, double hulls and complex piping carrying liquids? How can accurate and thorough checks be done avoiding dismantling or damage and ensuring no speck of rust has escaped detection?

The major company, DCN Brest, along with two small businesses, RoboPlanet and TE2M, are joining forces with the ENSIETA lab to design and produce the only detection system of its kind on the market. It will be more reliable and easier to deploy than any other inspection sampling systems currently available. Combining the areas of expertise of the two smaller companies – ultrasound and electromagnetic technology – the projected system involves plotting a dense network of inspection points across the entire surface of any type of naval or merchant vessel.

CORONAV will be offering an innovative solution to major problems encountered by ship repair yards, classification companies and also ship owners who, given increasingly stringent regulations governing maritime safety, will find it more and more in their interests to anticipate potential corrosion and maintenance problems in their fleets.