The Isherwood System of Ship Construction

ISHERWOOD SYSTEM

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Koninklijke Maatschappij

„De Schfilde"

Scheepsbouw en Werktuigenfabriek

T H E I S H E R W O O D S Y S T E M O F

S H I P C O N S T R U C T I O N .

( P A T E N T ) . S O L E L I C E N S O R :

J . W. I S H E R W O O D ,

Z E T L A N D B U I L D I N G S , M I D D L E S B R O U G H . A G E N T S F O R G R E A T B R I T A I N :

S. C . C H A M B E R S & C O . ,

3 , KING S T R E E T , L I V E R P O O L . T e l e g r a m s : " I S H E R W O O D , M I D D L E S B R O U G H / Nat. T e l . : 661.

TIE ISHERWOOD SYSTEM OF SHIP CONSTRUCTION.

D E S C R I P T I O N O F T H E S Y S T E M .

I

N the Isherwood transverse frames spaced intervals, having established th s t r u c t u r e s f o r m complete transverse belts around tbe ship.- , T h e y are directly riveted to the shell plating and deck of the vessel, and are made of not fess strength than the number of transverse frames that are fitted in ordinary vessels for a c o r r e s p o n d i n g l e n g t h of s h i p . These strong trans-verse girder frames are slotted around their outer edges, in order to admit of continuous

longi-" system of construction, the and beams are fitted at

^yidely-tlie general practice, so far, is at about 12 f t . These

I N T E R N A L V I E W OF S.S. " G A S C O N Y , " B U I L T FOR D A V I D MAC IVER A N D C O . , L I V E R P O O L .

tudinal stiffeners being fitted, not only at the decks, but on the sides, bottom and tank top.

The fitting of these longitudinal stiffeners directly on to the plating prevents damage to the decks

through buckling, which has been sustained in vessels of the ordinary construction which have had no fore and aft support to t h e p l a t i n g i n between the trans-verse beams.

I n vessels with d o u b l e b o t t o m s , t r a n s v e r s e floor plates are fitted i n t e r m e d i a t e t o those at the sides and decks of the v e s s e l . T h e s e intermediates enable sectional materials, such as bulb angles.

being utilised as longitudinals both at the tank top and on the outside plating, thereby providing a double-bottom construction, which is much more ready of access than one built on the ordinary system.

ADVANTAGES

O F

THE SYSTEM.

Greatly increased l o n g i t u d i n a l strength and the prevention of deck damage through buckling owing to the support given to the plating by the fitting of con' t i n u o u s l o n g i -tudinals. Reduced cost of maintenance due to a l l parts of the s t r u c t u r e b e i n g readily accessible. S.S. " S O P H I E H , " B U I L T BY K O N I N K L I J K E M A A T S C H A P P I J " D E S C H E L D E , " F L U S H I N G , H O L L A N D , FOR S T O O M V A A R T M A A T S C H A P P I J " S O P H I E H , " R O T T E R D A M

Increased capacity for bale goods and for bulky cargoes on account of the floor being carried flat to the side of the vessel and the absence of beam knees between the widelyspaced transverses.

Increased deadweight carrying capacity without additional cost to the owners of the vessel. T h i s is important, as the additional deadweight is gained without increasing the draught of the ship. T h e

saving in weight of material has been effected by dispensing with beam knees, a number of bilge b r a c k e t s , t a n k knees, p a c k i n g , and many trans-verse connections which are necess-ary i n vessels of the ordinary construction. I f the addi-tional deadweight capacity is not required, advan-tage of the saving in weight might be taken i n producing a finer model, and so provide a vessel easier to drive and, therefore, more economical i n the matter of coal consumption, and, at the same time, provide for the same cargo

C O N S T R U C T I O N A L V I E W OF LARGE S I N G L E - D E C K E D S T E A M E R " T R A B B O C H , " B U I L T BY A R C H . M o M I L L A N & S O N , L T D . , D U M B A R T O N , FOR W . N. B I C K E T , L I V E R P O O L .

capacity i n proportion to the deadweight of the steamer.

Limber space can be recovered and utilised for water ballast when desired, and without the objection' a b l e o b s t r u c t i o n

caused by the fitting of frame brackets as in the ordinary type of vessel when the tank top is carried out flat to the side of t h e ship.

Reduction of v i -bration owing to the continuous fore and aft support given to the plating of the structure.

There are few pillars required i n the holds, it being only necessary, except i n the case of a

I N T E R N A L V I E W OF O I L T A N K S T E A M E R " P A U L P A I X , " B U I L T FOR L E N N A R D ' S C A R R Y I N G C O M P A N Y , L T D .

vessel w i t h great beam, to f i t pillars at the centre line at each of the transverse beams. T h i s gives a spacing of about 12 f t . , and provides an admirable arrangement i n steamers i n which large unobstructed

spaces are required for handling and stowing large and bulky goods.

The hatchway pillars, which i n some cases have been fitted at the widelyspaced transverses abreast the hatchways, can be readily dispensed w i t h i f desired by the owner when the design is deter' mined upon, and this can be done without the " extra " required in vessels of the ordinary con-struction.

Improved ventila' tion due to the longitudinals f o r m ' ing fore and aft air courses. T h i s has been strikingly brought home i n the case of two " I s h e r w o o d "

ves-Plate trade, where sels employed in the River

there has not been a particle of sweat damage i n these vessels when carrying grain either i n bags or i n bulk. T h i s matter of ventilation w i l l be

found of great value for the r i c e ' c a r r y i n g trade.

The system is particuJarly advan-tageous when ap-plied to theconstruc-tion of vessels de-signed for carrying oil or other liquid cargoes in bulk. The simplicity and ease of erection and construction permits of consider-ably more hydraulic r i ^ ' e t i n g b e i n g done o n t h e ground, and most o f t h e i n s i d e riveting, caulking and general finish-ing off can be done to a much greater extent before the outside plating is fitted, or whilst it is being fitted.

The system has met with great success, and has been adopted by

vessels engaged i n many prominent shipowners, and, although the first steamer has only been at sea for 18 months, there are now 47 vessels built, or building, representing about 165,000 gross tons. The dimensions of these vessels range f r o m l 7 0 f t . t o 4 4 0 f t . for sea-going ships, t h e d e a d w e i g h t carrying capacity of the latter being nearly 11,000 tons. An ore carrying steamer, 580f t. long, is now being con-structed for trading on the Great Lakes of America for the Pittsburg Steam-ship Company, of Cleveland, Ohio. The method of c o n s t r u c t i o n has the approval of Lloyd's Register of B r i t i s h and Foreign Shipping, B u r e a u V e r i t a s , I n t e r n a t i o n a l " T H E S S A L Y , " B U I L T BY R I C H A R D S O N , DUCK A N D C O . , FOR D A V I D MAC IVER A N D S O N , L I V E R P O O L . 1 4

C O N S T R U C T I O N A L V I E W S OF S.S. " T H E S S A L Y , " B U I L T BY R I C H A R D S O N , DUCK A N D CO., FOR D A V I D MAC IVER A N D CO., L I V E R P O O L

Register, Britisli Corporation for tlie Survey and The following shipbuilders are at the present time Registry of Shipping, Norske Veritas, and German- building, or have already built, on the " i s h e r w o o d " ischer Lloyd. DESIGN FOR S T A T E R O O M IN V E S S E L C O N S T R U C T E D ON T H E " I S H E R W O O D " S Y S T E M . system of construction : Messns. W . H A M I L T O N * Co., Ltd., P o r t Glasgow. Messrs. R I C H A R D S O N , DUCK & Co.

T h o i ' i i a b y - o n - T e e s . Messrs. A R C H D . M o M I L L A N & S O N , L t d .

D u m b a r t o n . Messrs. C A M M E L L , L A I R D & Co., L t d .

_ B i r k e n h e a d . Messrs. K O N I N K L I J K E M A A T S C H A P P I J . , de S C H E L D E , F l u s h i n g , H o l l a n d . Messrs. M A R Y L A N D S T E E L C O M P A N Y , S p a r r o w ' s P o i n t , U.S.A. Messrs. N E D E R L A N D S C H E S C H E E P S B O U W M A A T S C H P P I J . , A m s t e r d a m , H o l l a n d . IVlessrs. S H O R T B R O S . , L t d . S u n d e r l a n d .

Messrs. S i r W. G. A R M S T R O N G , W H I T W O R T H & Co., L t d . W a l k e r S h i p y a r d , N e w o a s t l e - o n - T y n e . Messrs. T Y N E IRON S H I P B U I L D I N G C O M P A N Y , L t d , ,

W i l l i n g t o n Q u a y - o n - T y n e .

Messrs. N E W P O R T N E W S S H I P B U L D I N G & DRY DOCK Co., N e w p o r t News, U . S . A .

Messrs. G R E A T L A K E S E N G I N E E R I N G W O R K S , D e t r o i t , U.S.A.

Messrs. E T A B L I S S E M E N T F I J E N O O R D , R o t t e r d a m , H o l l a n d . Messrs. H A L L , R U S S E L L & Co., L t d . ,

A b e r d e e n . Messrs. B L O H M & VOSS,

H a m b u r g , G e r m a n y .

IN ADDITION SEVERAL OTHER SHIPBUILDERS ARE PREPARED TO BUILD ON THE SYSTEM,