Auxiliary marine machinery systems

#Engines #Marine science #

1. AUXILIARY Marine MACHINERY SYSTEMS Submitted to: Prof. N.A.TALWAR Submitted by: ASK IKBAL M.F.Sc 1 st year 1 st sem. Dept. of Fishery Engineering. FET-505

2. Introduction Marine machinery is designed to ensure the proper functioning of a ship’s main engines, piping systems, and equipment. Auxiliary marine machinery includes pumps, compressors, and blowers for circulating fuel and the fresh water and seawater used in cooling systems, for supplying air to the starting system of the main engine, for cooling refrigerated holds, and for air-conditioning various parts of the ship and for refrigeration machinery . Auxiliary marine machinery also includes separators for removing water and other contaminants from fuel and oil, steering machinery, capstans, windlasses, winches for anchoring, mooring, and cargo loading, and cranes.

3. A ship might reasonably be divided into three distinct areas: the cargo-carrying holds or tanks, the accommodation and the machinery space . Depending upon the type each ship will assume varying proportions and functions. An oil tanker, for instance, will have the cargo-carrying region . The accommodation areas in each of these ship types will be sufficient to meet the requirements for the ship's crew, provide a navigating bridge area and a communications centre. The machinery space size will be decided by the particular machinery installed and the auxiliary equipment necessary . Machinery space requirements will probably be larger because of air conditioning equipment, stabilisers and other passenger related equipment.

4. Auxiliary Engines (Diesel Alternator) The engines used to drive the generators/alternators are the vessels primary source of power. This must always be taken into account in establishing priorities with regard to the operation, maintenance, and ordering of spares. It is essential that the manufacturer’s instructions are closely followed with regard to maintenance and overhaul of critical components such as connecting rods, bottom end bolts, shell bearings, pistons.

5. Steering gear Every ocean going cargo ship need to be provided with a main steering gear and an auxiliary steering gear unless the main steering gear comprises two or more identical power units . The main steering gear is to be capable of putting the rudder over from 35° on one side to 35° on the other side with the ship at its deepest draft and running ahead at maximum service speed, and under the same conditions from 35° on either side to 30° on the other side in not more than 28 seconds. The auxiliary steering gear is to be capable of putting the rudder over 15° on one side to 15° on the other side in not more than 60 seconds with the ship at its deepest draft and running ahead at half the maximum service speed or 7 knots whichever is greater.

6. Steering gear arrangement for cargo ships

7. The other auxiliary machineries includes Deck gears, Small deck machinery, Winches and Net and Line haulers.

8. Mast and Derricks Mast is a vertical spar primarily meant to carry sails but it is also used to carry radar, satellite aerials, and navigational lights. These are made either of wood or steel. Derrick is a large spar fixed to mast by goose neck and it is used like a crane for hoisting heavy weights.

9. Block, Pulleys and Fish pump These are common in all types of fishing vessel and are used for a variety of purposes like leading the ropes to convenient positions for handling the net. A block is a wooden or metal case in which one or more sheaves are fitted . Fish pumps are mainly used on purse seiners to transfer the catch from net to the deck.

10. Rollers and Gantries Powered stern rollers are used in gill netters to haul the gill nets by net reels. In Danish seiners, towing rollers are used to haul the rope. Gantry is a four-in-one contrivance used in trawlers which replaces gallows, mast, derrick and stays. It assists in positioning of warp leads, hitching of otter boards and lifting heavy catches etc.

11. Winches Winches are used commonly in trawlers, purse seiners and Danish seiners to haul the net and the catch on to the board. W inches are used for different fishing methods like single drum(split type), two-drum on one shaft or more drums on parallel shafts (double rigging and purse seining ). There are different kinds of winches. They are distinct from each other depending on their use. There are 7 types of winches currently available there. For example – Lever winch Snubbing Winch Wakeskate winch Glider Winch Air Winch Capstan winch Mooring winch They are placed in the fore and aft direction depending on the requirement. Winches can be driven either mechanically from the main engine or electrically or hydraulically or direct drive by separate engine.

12. 1. Lever Winch: Lever winches are particular kinds of winches that do not use spools. Instead of a spool, they have Self-gripping jaws. Therefore, they use Self-gripping jaws for moving cable or rope through the winch. One can move several tons of weight only by moving a handle back and forth by using a lever winch. 2. Snubbing Winch: Snubbing winch is a winch of a vertical spool. It has ratchet mechanism like a conventional winch. But it has no crank handle or another type of drive like a standard winch.The line can be reeled and tightened by pulling tail line. Snubbing Winch also allows a controlled release of pressure.To control stress, it uses an operator around the ratcheted spool. Also, it controls pressure using the friction of the line. 3 . Wake-skate Winch: Wakeskate winch using is growing widely among the watersports enthusiasts. It is a favorite pastime for them. It forms of a spool, engine, frame, handles, rope and other types of simple transmissions. 4 . Glider Winch: For launching a glider or plane, we use a particular type of winch. It is the glider winch. Usually, we fit them to a heavy vehicle or a trailer. This method is a cheaper alternative to aerotowing.European gliding clubs widely use this method. In a glider winch, the engine is usually of petrol, diesel or LPG. You will also find winches having electric or hydraulic engines.This winch can pull in a 1000 to 1600-meter cable attached to the glider. After a steep and short climb, you can release the cable at the height of 400 to 700 meters. 5 . Air Winch: Air winch is also known as air tugger or air hoist. This winch is the air- powered version of a winch. It can lift the materials. You can also utilize them for the suspension of materials.They are more durable, versatile and safer than hydraulic, diesel and electric winches. That's why various companies often prefer to use air winches. 6. Capstan Winch: Capstan winch is a vertical-axle winch. It is a rotating device made for using on sailing ships. Sailors use this winch in sailing ships to apply force to the cables and ropes. The principal of the capstan winch is similar to the windlass. 7. Mooring Winch: Mooring winch is a mechanical device. It is used to secure a ship to the berth. It is a device with some barrels that pulls the cables or wires. To berth, the ship ashore mooring winch plays a significant role.

13. Windlass Windlass is special type of winch used for handling anchor chain. This is also be driven with electric or hydraulic.

14. Net Haulers and Net Drums Net haulers are designed to suit the fishing method and popular mostly on trawlers, gill netters and purse seiners. They may be fitted on the rails on deck or hung from a boom. Net haulers can be driven mechanically, electrically or hydraulically. Net Drums are used in gill netting, trawling and seining. They differ from net haulers in that the entire net is wound on the drum. Most net drums are fitted at the stern. These also prevent the fouling of the gear during the operation.

15. Line Haulers Line haulers are used in heaving the lines. Line haulers are used in hauling the trolling lines, handlines and jigging lines. Other machineries like water separators, coiler, brailer , power blocks, triplex, jigging machines etc.

16. Conclusion Auxiliary Machineries are having very usages for boat deck arrangement and vessel or ships management. Many auxiliary Machineries are used in capturing fish holds and for casting the various nets, lowering the manoeuvring power as well as working loads.

17. References: http:// www.pfri.uniri.hr Fishing Gear and Craft Technology - Y. Sreekrishna and Latha Shenoy www.google.com/images