The design and construction of ships
THE DESIGN AND CONSTRUCTION OF SHIPSBY JOHN HARVARD BILES
VOL I - CALCULATIONS AND STRENGTH,
LONDON, CHARLES GRIFFIN AND COMPANY, 1908.
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PREFACE
This book cannot possibly lay any large claim to originality. The greater part is necessarily the work of others who went before or who are now working for the advancement of the science of Naval Architecture. Very little attempt has been made to acknowledge the sources of such help. The subject is too wide to attempt to acknowledge all the sources, even if one were qualified to do so. But there are parts which are original work given for the first time in the lecture-room, though some has been already published, mostly in the Transactions of the Institution of Naval Architects,
The subject is developing year by year, and often so rapidly as to make it very difficult, if not almost impossible, to read all that is published on the subject. There are further stores of knowledge which are never published, and are only accessible to individuals associated with the shipbuilding establishments, in which much expense is incurred in investigations and experiments for the advancement of knowledge of the subject. To many such I have been indebted from time to time for the ready reply to requests for information. It would be difficult to name all these individuals, but from circumstances of close proximity and old friendships, as well as their ability to give, the firms of Messrs John Brown & Co. and Messrs Wm. Denny Brothers have been most severely taxed by demands of all kinds, to which they have never failed to accede. My thanks to these and all others who have assisted me are gratefully offered.
This book is primarily intended for young students, but it is hoped that many who have been students, and some who in their daily work are interested in the problems dealt with, may find some assistance. There must be some errors and shortcomings in such an attempt ; but it is sincerely hoped that, in spite of these, the work may serve the purpose of assisting some to a better knowledge of the science of Naval Architecture.
The subject is developing year by year, and often so rapidly as to make it very difficult, if not almost impossible, to read all that is published on the subject. There are further stores of knowledge which are never published, and are only accessible to individuals associated with the shipbuilding establishments, in which much expense is incurred in investigations and experiments for the advancement of knowledge of the subject. To many such I have been indebted from time to time for the ready reply to requests for information. It would be difficult to name all these individuals, but from circumstances of close proximity and old friendships, as well as their ability to give, the firms of Messrs John Brown & Co. and Messrs Wm. Denny Brothers have been most severely taxed by demands of all kinds, to which they have never failed to accede. My thanks to these and all others who have assisted me are gratefully offered.
This book is primarily intended for young students, but it is hoped that many who have been students, and some who in their daily work are interested in the problems dealt with, may find some assistance. There must be some errors and shortcomings in such an attempt ; but it is sincerely hoped that, in spite of these, the work may serve the purpose of assisting some to a better knowledge of the science of Naval Architecture.
CONTENTS
PART I - AREAS, VOLUMES, AND CENTRES OF GRAVITY
PART II - SHIP CALCULATIONS
PART III - STRENGTH OF SHIPS
INTRODUCTION - GENERAL CONSIDERATIONS
Usually the problem of making a ship is one of doing something very like what has been done before. To understand fully how to make a new ship, it is necessary to study the qualities and history of creation of existing ships.
The finished ship is generally first seen floating at rest in smooth water. All the forces acting upon the ship are in equilibrium. The weight of the whole structure and all the ship contains must be balanced by the supporting forces of the water. The pressures of the water on the sides and bottom of the vessel are balanced by the resistances of the material to change of form. The vessel, when floating in absolutely smooth water, is in such a condition that a small inclination from its position of rest is not followed by an increased departure from this position, but by a return to it. This tendency is known as the stability of the vessel.
If we consider the duty which a ship has to perform by moving in smooth water, we see that force from some source has to be developed equal and opposite to the resistance to be overcome. If the circumstances are still further complicated by the water not being smooth, the ship will have movements other than in the direction of intended locomotion, and the movements impressed upon one part of the vessel will develop resistances to change of form in the material of the structure. These resistances are known as the strength of the ship.
When the vessel is in disturbed water, her movements other than directly forward will be oscillatory about the position of rest in smooth water.
The result of this general survey is that we must consider the vessel from the following points of view:
- Support or buoyancy
- Resistance
- Strength
- Oscillations
- Stability
The book has therefore been divided into Parts which treat the subject as follows:
VOLUME I
Part I. Areas, Volumes, and Centers of Gravity
Part II. Ship Calculations
Part III. Strength
VOLUME II
PART IV. Stability
Part V. The Theory of Waves: Oscillations of a Vessel among Waves,
Part V. Resistance and Propulsion
Part VII. Design
Part VIII. Construction
The finished ship is generally first seen floating at rest in smooth water. All the forces acting upon the ship are in equilibrium. The weight of the whole structure and all the ship contains must be balanced by the supporting forces of the water. The pressures of the water on the sides and bottom of the vessel are balanced by the resistances of the material to change of form. The vessel, when floating in absolutely smooth water, is in such a condition that a small inclination from its position of rest is not followed by an increased departure from this position, but by a return to it. This tendency is known as the stability of the vessel.
If we consider the duty which a ship has to perform by moving in smooth water, we see that force from some source has to be developed equal and opposite to the resistance to be overcome. If the circumstances are still further complicated by the water not being smooth, the ship will have movements other than in the direction of intended locomotion, and the movements impressed upon one part of the vessel will develop resistances to change of form in the material of the structure. These resistances are known as the strength of the ship.
When the vessel is in disturbed water, her movements other than directly forward will be oscillatory about the position of rest in smooth water.
The result of this general survey is that we must consider the vessel from the following points of view:
- Support or buoyancy
- Resistance
- Strength
- Oscillations
- Stability
The book has therefore been divided into Parts which treat the subject as follows:
VOLUME I
Part I. Areas, Volumes, and Centers of Gravity
Part II. Ship Calculations
Part III. Strength
VOLUME II
PART IV. Stability
Part V. The Theory of Waves: Oscillations of a Vessel among Waves,
Part V. Resistance and Propulsion
Part VII. Design
Part VIII. Construction
SHIPS FOR PASSENGER AND CARGO CARRYING
The next class of vessels we have to consider is the class for carrying passengers and cargo. Of this class there is a large number of different types, which to describe in detail would be too laborious a task.
Some merchant vessels are driven by the wind pressure on the sails. Even at the present time, when the method of driving by steam is in such a state of perfection, some sailing-vessels can still be run with profit, and new ones are still occasionally ordered.
Practically all sailing-vessels are used only for cargo-carrying purposes. There is no special point requiring notice in the construction of the hull: it is merely a shell, with one or two continuous decks.
Only one bulkhead is necessary, the forward or "collision" bulkhead. Nearly all the space in the hull is available for carrying cargo, and there is the advantage that the holds are free and open, except for the pillars and masts, thus allowing the stowage of long timbers, rails, or beams. The only erections are usually a poop and a forecastle for accommodation and ship's stores. Sometimes there is a house amidships in which the crew is housed. The masts are carried through the decks and stepped on the floors above the keel.
An important point in a sailing-vessel is the rig. There are different types of rigs.
A schooner is rigged fore and aft on each mast (fig. 40), and may have as many as seven masts. Some schooners have one or two square sails on the foremast (fig. 41), and are called topsail schooners.
A brigantine is a vessel square rigged on the foremast and fore-and-aft rigged on the main (fig. 42).
A brig is a vessel square rigged on both masts (fig. 43).
A barque has two masts square rigged and one fore-and-aft rigged (fig. 44).
A barquentine has one mast square rigged and two masts fore-and-aft rigged (fig. 45).
A ship has three masts square rigged. Some ships have four masts, sometimes three only being ship rigged and the fourth fore-and-aft rigged. The three masts of a ship are called fore, main, and mizzen, which are all square rigged.
In the four-masted ship the after mast is called the jigger (fig. 46).
Merchant steamers form by far the largest proportion of ships afloat. They carry on the commerce between the countries. Most of them, especially those carrying passengers, keep up a regular trade, and ply along fixed routes or lines and are called liners. They are mostly owned by shipping companies or companies engaged in a certain trade, and some of the passenger vessels are paid by the Government to carry the mails. Many steamers, however,
Many ships that are intended for passengers or cargo are built to a certain class of one of the Societies of Registration, among which may be mentioned "Lloyd's Register," "Germanischer Lloyd's," "Bureau Veritas," "British Corporation," and the "Record of American and Foreign Shipping."
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Some merchant vessels are driven by the wind pressure on the sails. Even at the present time, when the method of driving by steam is in such a state of perfection, some sailing-vessels can still be run with profit, and new ones are still occasionally ordered.
Practically all sailing-vessels are used only for cargo-carrying purposes. There is no special point requiring notice in the construction of the hull: it is merely a shell, with one or two continuous decks.
Only one bulkhead is necessary, the forward or "collision" bulkhead. Nearly all the space in the hull is available for carrying cargo, and there is the advantage that the holds are free and open, except for the pillars and masts, thus allowing the stowage of long timbers, rails, or beams. The only erections are usually a poop and a forecastle for accommodation and ship's stores. Sometimes there is a house amidships in which the crew is housed. The masts are carried through the decks and stepped on the floors above the keel.
An important point in a sailing-vessel is the rig. There are different types of rigs.
A schooner is rigged fore and aft on each mast (fig. 40), and may have as many as seven masts. Some schooners have one or two square sails on the foremast (fig. 41), and are called topsail schooners.
A brigantine is a vessel square rigged on the foremast and fore-and-aft rigged on the main (fig. 42).
A brig is a vessel square rigged on both masts (fig. 43).
A barque has two masts square rigged and one fore-and-aft rigged (fig. 44).
A barquentine has one mast square rigged and two masts fore-and-aft rigged (fig. 45).
A ship has three masts square rigged. Some ships have four masts, sometimes three only being ship rigged and the fourth fore-and-aft rigged. The three masts of a ship are called fore, main, and mizzen, which are all square rigged.
In the four-masted ship the after mast is called the jigger (fig. 46).
Merchant steamers form by far the largest proportion of ships afloat. They carry on the commerce between the countries. Most of them, especially those carrying passengers, keep up a regular trade, and ply along fixed routes or lines and are called liners. They are mostly owned by shipping companies or companies engaged in a certain trade, and some of the passenger vessels are paid by the Government to carry the mails. Many steamers, however,
Many ships that are intended for passengers or cargo are built to a certain class of one of the Societies of Registration, among which may be mentioned "Lloyd's Register," "Germanischer Lloyd's," "Bureau Veritas," "British Corporation," and the "Record of American and Foreign Shipping."
DOWNLOAD FREE SHIPBUILDING BOOK:
The design and construction of ships
