Section 3. Ship’s principle dimensions

Words and Terms to be Remembered

Read the text and find the answers to the following questions.

1. What is a classification society?
2. What does classification imply?
3. What principle classification societies in the world are known?
4. When are classification certificates issued?

CLASSIFICATION SOCIETIES

Every ship is designed and constructed to the certain class and is operated in the conditions related to the given class. Class means the character assigned to a vessel by a classification society, depending on the design of the vessel, the quality of materials employed, the scantlings of the various structural members, and the outfit and equipment, all of which should be up to the standard specified by the society's rules. To ensure that the condition and seaworthiness of classed ships are maintained they are examined periodically and upon the result of such survey depends the continuance of the class.

Classification society is a special institution which has as its purpose the supervision of vessels during their construction and afterwards, in respect to their seaworthiness and upkeep, and the placing of vessels in grades or "classes" according to the society's rules for each particular type of vessel. The principle classification societies are: Lloyd's Register, London; American Bureau of Shipping, New-York; Bureau Veritas, Paris; Germanischer Lloyd, Berlin; Norske Veritas, Oslo; Japanese Marine Corporation, Tokyo; Russian Maritime Register of Shipping, St. Petersburg. Lloyd's Register of shipping is the largest and oldest British classification society, established in 1834.

The Classification Societies are known to have a profound influence on shipping, ship design and ship safety. The fundamental purpose of classification is to ensure maintenance of seaworthiness of all classed ships. Withdrawal of a class means cessation of the Register supervision when renewal of a class seems impossible for the Register. The class might be withdrawn by the Register at the shipowner's desire as well. The Classification societies operate throughout the world and publish rules and regulations directly related to the structural efficiency of the ship and the reliability of the propelling machinery. Classification implies the ship and the machinery to conform to the standards published in the rules of the Society.

Classification societies' rules are not absolutely rigid in every detail, as the progress of shipbuilding methods and materials makes it necessary that a certain amount of latitude be allowed. They represent the minimum standards which the society considers necessary for a particular type of vessel. In classed vessels the materials and the actual construction are under the supervision of the society's surveyors. At the completion of the building and after trials at sea, classification certificates are issued and handed to the owners.

Classification certificate states that the ship has been found to comply with the rules of the society. It also mentions the class granted to the ship and the conditions which have to be complied with if the class is to be maintained. The record in the Register Book is given in symbols.

100A.1. indicates the highest class for steel ships and is assigned to all vessels built under survey and in accordance with the society's rules and regulations. The figure 1 after letter A indicates that the anchors and cables have been tested by the society's surveyors and are in accordance with the rules and in good condition. If there is anything amiss, it is replaced by a dash, so "100A.1." and "100A.-" respectively. The class 100A.1. is followed by the descriptive notation, such as "oil tanker", "bulker", etc. The Maltese cross indicates that the vessel has been built under survey.

L.M.C. signifies that a "Lloyd's Machinery Certificate" has been granted.

Surveys, repairs and any alterations to the hull or machinery of the vessel are mentioned on the certificate. Two certificates are issued to the mechanically propelled vessels, one for the hull and another for the engines and/or boilers.

Exercises and assignments

Ex. 1. Form the nouns from the following verbs. Find them in the text and translate the sentences in which they are used.

Ex. 2. Arrange the given words into the pairs of synonyms. Find in the text the sentences in which they are used and translate the sentences into Russian.

Ex. 4. Review the vocabulary items. Match the explanations with vocabulary items.

Section 3. Ship’s principle dimensions

Words and Terms to be Remembered

Read the text and answer the following questions.
1. What are the ship's principle dimensions?
2. What is the difference between the overall and extreme dimensions?
3. Do the principle dimensions influence the ship hull shape?

PRINCIPLE DIMENSIONS OF A SHIP

The principle dimensions of ships are the combination of constructive, designed and overall ship's measurements. They are: length, breadth and draught.
Length between perpendiculars (Lbp) is the distance between fore and aft perpendiculars on the constructive waterline plane. Forward perpendicular (F.P.) is a vertical line through the intersection of the load waterline with the fore side of the stem. After perpendicular (A.P.) is a vertical line through the intersection of the load waterline with the after side of rudder post.
Length overall (Loa) is the greatest length of a vessel from the extreme fore end to the extreme after end without projecting parts. Lloyd's or registered length is measured from the fore edge of stem to the after edge of sternpost at the level of the upper deck.
Breadth (B) or beam is the width of a ship. Extreme breadth is the greatest one to the outside of plating. Breadth moulded (Bm) means the greatest breadth of a ship to the outside of frames.
Depth (H) is the vertical distance measured at the middle of the vessel's length from top of keel to top of upper deck at sides, or to the top of the upper deck beam for designed depth. The designed depth depends on the draught and freeboard required.
Draught, draft (T) is the depth of water which a ship requires to float freely. It's the depth of a vessel below the waterline, measured vertically to the lowest part of the hull, propellers or other reference points. Extreme draft is the vertical distance from the designed waterline to the lowest projecting portion of the vessel at any point in a vessel's length.
The principle dimension ratios give the idea of ship hull shape and potential possibilities of ensuring some operational qualities of a vessel. The greater the L/B ratio, the faster the ship; the greater the B/T ratio, the better the ship stability; the greater the H/T ratio, the higher the degree of unsinkability.

L_bp

A.P. F.P.

Fig. 6.

Exercises and assignments

Ex. 1. Give the initial forms of the following nouns and translate them into Russian:
length, breadth, depth, width, measurements, combination, construction, plating, possibility, operation, reference, unsinkability.

Ex. 2. For the words in (a) find the synonyms given in (b):
a) length, breadth, draught, dimensions, designed, overall, upper, project, ratio, fast, principle;
b) relationship, distance, immersion, width, whole, moulded, measurements, top, high-speed, protrude, basic.

Ex. 3. Give the forms with -ed in the function of attribute from the following verbs. Find corresponding nouns for them in the text and translate the word combinations into Russian:
to design, to measure, to register, to mould, to frame, to require, to receive, to calculate.

Ex.4. Give Russian equivalents for the following word combinations. Consult a maritime dictionary:
moulded dimensions, limiting dimensions, overall dimensions, linear dimensions;
registered length, waterline length, overall length;
extreme breadth, overall breadth;
freeboard depth, registered depth, moulded depth;
after draught, allowable draught, forward draught, full draught, ballast draught, designed draught.

Ex.5. Compare the principle particulars of the two different vessels.

M/V "FORTUNA COAST"
Multipurpose vessel

Fig. 7.

M/V "PRESIDENT TRUMAN"

Container carrier

Fig. 8.

Date: 2014-12-28; view: 2730