Lesson 6 Decks and Hatches

1. Lesson 6Decks and Hatches

2. Contents • Decks at different levels in a ship. • Deck construction. • Deck plating. • Deck stiffening.

3. Lead-in Look at the picture and point out the following places: main deck, second deck, compass deck, boat deck, bridge deck, poop deck.

4. compass deck bridge deck boat deck accommodation deck poop deck forecastle deck cargo deck watertight deck strength deck freeboard deck lighter deck Language knowledge

5. BC:Bulk Carrier 散货船 COT:Cargo Oil Tanker 货油轮 DFF:高速渡轮 ERRV:救援船 FLNG:浮式液化天然气船（科代替岸上传统的液化天然气工厂） FPSO:浮式生产储油船 FPV:浮式生产设备 G-Cargo Ship:杂货船 LNG:液化天然气船 Roll-on/Roll-off ship:滚装船 UCLL: Ultra Large Crude Carrier: 超大型原油轮 各种船型英文缩写 LEG:液化乙烯汽船 LPG:全压式液化石油汽船 LSV:驳运支援船 LR成品油轮:stands for large range,远程成品油轮 MR成品油轮:stands for medium range,中程成品油轮 OSV:Offshore Support Vessel,海洋工程船 PSV:平台供应船 PC:重型石油化学制品运输船 PCC:Pure Car Carrier 汽车运输船 PCTC:Pure Car & Truck Carrier 大型轿车卡车专用船 RO-RO SHIP:客滚船

6. WORD FORMATION • en- • enable • encourage • encounter • enclose • endanger • engulf • enrich Prefix: dis- • disable • disadvantage • disagree • disappear • disapprove • disclose • disconnect • displace

7. Grammar: • Ellipsis • 1. The stringer plate (i.e. the strake of deck plating adjacent to the sheer strake) of ships less than 260m in length is of Grade B steel if the thickness is more than 15mm, Grade D if more than 25mm thickness over the amidships region and within the cargo hold region of container ships. • 2. and on superstructure decks the plating thickness may be further decreased within deckhouses, if sheathed, before fitting any form of sheathing the deck is treated to prevent corrosion between the deck plating and sheathing.

8. Grammar • Independent Nominative Structure • 1. The weather decks of ships are cambered, the camber being parabolic or straight. • 2. Within the forward 7.5 percent of the ship’s length, the forecastle and weather deck transverses are closely spaced and the longitudinal scantlings increased, the additional transverse and longitudinal stiffening forward being designed to avoid buckling of the deck plating on impact when shipping seas.

11. Watertight decks are fitted to maintain the integrity of the main watertight hull and the most important is the freeboard deck which is the uppermost deck having permanent means of closing all openings in the exposed portions of that deck. Although all decks contribute to some extent to the strength of the ship, the most important is that which forms the upper flange of the main hull girder, called the ‘strength deck’. • Weather decks may be covered with wood sheathing or an approved composition, which not only improves their appearance, but also provides protection from heat in way of any accommodation. • Both longitudinal and deck beam scantlings are increased in way of cargo decks where forklift trucks, and other wheeled vehicles which cause large point loads, are used. • In ways of the hatches fore and aft side girders are fitted to support the inboard ends of the half beams, and transverses. At the ends of the hatches heavy transverse beams are fitted and these may be connected at the intersection with the hatch side girder by horizontal gusset plates. Where the deck plating extends inside the coamings of hatches amidships the side coaming is extended in the form of tapered brackets.

12. Bird’s view of deck construction

15. Assignment • Memorize the language points . • Extended readings • Where will the heaviest deck plating be found? • Name the decks at different levels in a ship?