Glossary of Terms
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ABANDONMENT Giving up the proprietary rights in insured property to the underwriter in exchange for payment of a constructive total loss
ACETONE Solvent particularly effective for cleaning tools soaked in uncured resins and for preparing a GRP surface before further laminating
ACTUAL TOTAL LOSS This occurs when: the insured property is completely destroyed; the assured is irretrievably deprived of the insured property; cargo changes in character so that it is no longer the thing that was insured e.g. cement, water damaged becomes concrete. A ship is posted "missing" at Lloyds.
ADVENTURE The exposure of property to risk
AERODYNAMIC Term relating to the behaviour of air (or other gas) under conditions of motion
AFT Toward, at, or near the stern
AIR PIPE Fitted to water ballast and oil tanks and led to the upper deck to allow the escape of air when the tanks are being filled
ALLOWABLE STRESS Design-targeted maximum stress in the material of a structure; less than the materials breaking strength in order to provide a factor of safety
ALLOY A mixture of metals plus, usually, non-metallic elements
ALOFT Up the mast; high up
AMERICAN BUREAU OF SHIPPING [ABS] A classification society that provides a service in regulating the construction and equipping of vessels
AMID SHIPS The portion of the ship at half its length
ANGLE OF SHEAR Angle of distortion resulting from shearing stress
ANGLE SECTION Stiffener, manufactured in long lengths and usually in metal, the section being of L form
ANISOTROPIC Term describing a material that possesses directional properties, notably strength and stiffness
ANNULAR GROWTH RINGS A trees growth rings, approximately circular in form, as seen in a tree section
APPROVED An "approved" vessel is one which the underwriters deem adequate to carry the insured cargo, at the agreed rate of premium
ARAMID FIBRE A synthetic, long-chained aromatic polyamide fibre possessing high tensile strength
ARBITRATION Method of settling disputes which is usually binding on the parties concerned
ARGON ARC Metal welding process in which the weld is surrounded by the inert gas argon
ASPECT RATIO Ratio of length to width; greater to lesser spacing of frames and longitudinals
ASSIGNMENT The passing of beneficial rights from one party to another
ASSURED Party indemnified against loss by means of insurance
ATHWARTSHIPS At right angles to the centre-line of a boat
AT THE FLYWHEEL Indicating that measured engine power is gross, not accounting for the energy used to rotate the transmission or the engines ancillaries
AUXILIARY BOILER Used for duties other than main propulsion but may still be very large boilers as found on tankers when cargo discharge is done using cargo pumps driven by steam turbines
AVERAGE A marine partial loss
AVOIDANCE The right of an underwriter, in the event of a breach of good faith or delay in commencement of an insured voyage, to step aside from the insurance contract and to treat it as though he never accepted the risk
BACKBONE Main centreline structural assembly of a yacht of traditional wood construction
BACKSTAY Stay running from high up the mast to the aft end of a yacht, in order to restrain downwind sail loads
BACKSWEPT SHROUDS Shrouds attached to the hull aft of the mast step rather than in line with the mast athwartships
BALLAST Any solid or liquid weight placed in a ship to increase the draught, to change the trim or to regulate the stability
BALLAST KEEL BOLTS Fastenings used to attach the ballast keel to the hull of a yacht
BALLAST TANK A watertight compartment to hold water to improve the ships stability
BANK GUARANTEE An undertaking given by a bank to pay a claim sometime in the future should the Member be found liable and the undertaking is provided by the bank for the Association
BARGE A flat bottomed vessel for carrying cargo
BARREL Effect in which the section of a relatively short compressive member increases when the material exceeds its elastic limit
BATTEN To "batten down" is to secure the hatchway tarpaulin
BEAM Fitted in the fore part of a ship to prevent vibration
BEAM SHELF Substantial structural member, used for boats of traditional wood construction, fastened along the upper edges of the hull
BEAM THEORY Engineering theory that permits a prediction of the structural behaviour of a beam under bending loads
BEDDING COMPOUND Putty-like material used to aid the fit and watertightness of non-glued joints
BENDING Consequential curvature in a structural member, as a result of loadings perpendicular to the axis
BENDING MOMENT (AT A SECTION) Sum of the moments about the section of all the forces acting to one side or the other of it
BERTH Where a ship is tied up or docked or a place to sleep aboard
BIAS Direction in a fabric at 45 degrees to the warp and weft
BILGE Curved portion between the bottom and the side shell plating, drainage space within the ship
BILGE STRINGER Longitudinal positioned at the bilge
BILL OF LADING A receipt for the cargo received into the care of the carrier must be issued to the shipper by the carrier. 1. Evidence of the contract of carriage 2. Title to the goods 3. Receipt for the goods
BIMETALLIC CORROSION As galvanic corrosion
BLOCK COEFFICIENT Ratio of the underwater volume of a vessel to the cuboid that surrounds the volume
BODY PLAN A drawing depicting the sections of the hull
BOLLARD Fitted for the purpose of securing ropes
BONA FIDE In good faith, without fraud or deceit
BOTTLESCREW Device used to adjust the tension of shrouds and stays
BOW LINE As for a buttock line, but forward of amidships
BOWS NOTATION System of analysis in which the loadings in the members of a space- frame may be represented by a complex, complete vector diagram, the spaces and vectors being labelled appropriately as an aid to its construction
BRAKE POWER Power of an engine at the flywheel
BRITTLE Term describing a material apt to fracture readily when subject to a sudden load
BOWTHRUSTER An additional motor driven propulsion unit to provide transverse movement
BROKER A person who transacts the business of negotiating between merchants and ship owners respecting cargoes and clearances, or one who effects insurances with underwriters
BUCKLE Failure of a strut when not in column
BULBOUS BOW A ship which has a bulbous profile which improves the speed and efficiency/characteristics of the vessel
BULKHEAD A crosswise/longitudinal division of a ship
BULWARK The plating fitted for protection at the sides of a ship on and above the weather deck
BUNKER Ships fuel
BUOYANCY Upthrust, as a result of water pressure; for equilibrium, the buoyancy of the hull is equal to the weight of the vessel
BUOYANCY TANK Watertight compartment in the hull intended to provide buoyancy when the hull is otherwise filled with water
BUTTOCK LINE Imaginary line on the hull resulting from a vertical cutting plane aft of amidships and parallel to the centerline
BUTT Meeting of two planks or other members end to end
BUTT JOINT Joint formed between the ends of two members that come together but do not overlap
BUTT STRAP Member that bridges a butt joint, providing strength
CALL The premium charged by a P & I Club
CANTILEVER Fixed-end beam, otherwise unsupported
CARBON (FILTER) Treated polyacrylonitrile fibre, with high strength and modulus
CARGO INTERESTS Parties having an interest in the cargo.
CARLING Construction member running fore and aft to give support to the inner ends of half beams in way of the superstructure
CARRIER Operator or charterer of a ship, usually a ship owner
CARVEL System of wood hull construction in which the planks are laid flush and edge to edge
CATALYST Chemical agent that initiates the curing of polyester resin (in context)
CATENARY Curve, and hence structural configuration, of a flexible member subject to a uniformly-distributed load and resisted by placing the member in tension
CAULKING Process in which caulking cotton is forced in to the seams, primarily for watertightness
CAULKING COTTON Bundled cotton fibres, available in long lengths, for caulking
CAULKING IRON Tool used for driving in caulking cotton
CENTRE OF EFFORT Centre of force of the wind in the sails, usually considered when sailing upwind
CENTRE OF GRAVITY Point at which the weight of an object may be considered to act
CENTRE OF LATERAL RESISTANCE Centre of force of the water on the hull, keel and rudder combination
CENTRIFUGAL SEPARATORS Used on ships to treat fuels and lubricating oils. They spin at very high speeds, typically 6000 rpm and separate out water and solids.
CERTIFICATE OF ENTRY A document issued by the Association which records the names of Members interested in, and is evidence of a contract of insurance in respect of, an entered ship.
CENTROID Centre of an area; centre of gravity if the area were represented by a material of consistent thickness
CESSER When a term comes to an end
C-FLEX One-off GRP construction based upon longitudinal glass fibre-resin rods
CHAINPLATE Fitting enabling rigging to be attached to the hull or deck
CHARTERER Person who hires a vessel either on a voyage or for a period of time
CHARTERPARTY A contract between a ship owner and a party who hires his ship for an agreed period of time, or for a specific voyage or a series of voyages
CHINE 1. Corner where adjacent hull panels meet, other than on the centerline; 2. As chine log
CHINE LOG The longitudinal member to resistance over that of mild steel to which the panels are fastened at the chine
CHOPPED STRAND MAT Glass-fibre reinforcement material, comprising of short strands randomly bound with an agent to form a mat, available in different thicknesses (weights)
CLASSIFICATION LENGTH Hull length as defined by a classification society
CLASSIFICATION SOCIETY Bodies approved by governments to ensure the practical enforcement of statute for the safety of life at sea
CLEAT A fitting having two horns around which ropes may be tied, a clip on the frames to hold the cargo battens in place
CLEW Lower, aft comer of a sail
CLINKER System of wood hull construction in which the edges of the planks overlap and are through-fastened
CO-INSURANCE Where two or more parties share the same insured risk
COLD MOULDING Process of modern wood construction in which layers of planks of veneer are built up using a resin adhesive able to cure at room temperature
COLLISION Physical impact between two or more ships or vessels used for navigation
COMPOSITE Construction comprising two or more distinct materials
COMPOUND CURVATURE Curvature in more than one direction of a panel, as for a sphere
COMPRESSIVE Able to compress; nature of the forces tending to reduce length in the line of the forces and the accompanying stress
COMPRESSOR A means of producing air
CONICAL PROJECTION System employed for the design of sheet material boats in which each panel takes the form of part of the surface of a cone
CONIFEROUS Type of tree that typically retains its needle-like leaves all the year round
CONSTANT CAMBER Hull design system for cold-moulded construction in which planks of veneer, having identically-shaped edges, are laid on a mould with a constant form both longitudinally and transverse
CONSTRUCTIVE TOTAL LOSS Where the assured abandons the subject matter insured to the underwriter and claims a total loss.
CONTRACT OF AFFREIGHTMENT Contract for the carriage of goods by sea in return for payment
CONVERSION Sawing of logs into usable boards
COOL DOWN SURVEY The process by which the refrigeration equipment is checked to be operating within its designed parameters. It is used to identify the possible existence of insulation deficiencies
CORE Lightweight material separating the two faces of a sandwich panel
CORE MAT Plastic-based, cellular core material, able to absorb resin which produces a secure connection between the faces of a sandwich panel
CORRESPONDENT Representatives of the Association who are based in all major and minor ports throughout the world. Correspondents can be maritime lawyers, ships agents or in some cases surveyors
COR-TEN A type of steel, sometimes used for hull construction, providing slightly greater strength and improved atmospheric corrosion resistance over that of mid steel
COAMING The vertical plating bounding a hatchway
COFFERDAM Narrow space between two bulkheads or floors that prevents leakage between adjoining compartments
COUNTER STERN Characteristic stern which extends beyond and above the waterline
COUPLE Pair of equal forces acting in opposite and parallel directions
CRIMP Undulation of individual yarns or rovings resulting from the weaving of fibre reinforcement fabric
CROSS-LINKED FOAM Foam, usually PVC, of high strength and stiffness, the result of its cellular structure
CUP Movement, producing hollowing in the section of a plank of wood
CURE Chemical reaction resulting in the solidification of a synthetic resin
CYCLES [OF STRESS REVERSAL] Number of times the loading and therefore stress in a material changes
CYLINDRICAL PROJECTION SYSTEM Employed for the design of boats to be constructed from sheet material in which each panel can be envisioned wrapped around a cylinder, usually of varying diameter
DAVITS The supports under which the lifeboats are stowed and from which they are launched overboard
DART Removal of a V-shaped piece of material from a panel where excess occurs as a cone result of compound curvature, the cut edges of the panel then being joined
DEADRISE Angle (usually) between one side of the bottom of a hull and the horizontal
DEADWEIGHT The difference in displacement between the light and load waterlines
DECK BEAM Transverse structural member supporting the deck and linking the gunwales or beam shelves
DECK LOG A book where records of the vessel's navigational progress and daily events are kept
DECIDUOUS Term describing trees that shed their leaves before the onset of winter
DEDUCTIBLE Sometimes called an "excess" is the amount the Member agrees to pay or is required to pay in respect of a particular claim.
DEEP-V HULL Powered craft hull form with an angle of deadrise of the order of 25 degrees, carried through to the transom
DEMURRAGE Charge made by ship owner or wharf owner for delay in unloading or loading
DEMISE CHARTER PARTY A charter party under which the ship owner provides vessel, and charterer crew and cargo
DERRICK A wood spar or steel tube used for discharging or loading dry or packaged cargo
DESIGN LOAD Assumed load on a structure to serve as the basis for its design
DESIGN SPIRAL Classic approach to design in which the design considerations are revisited at increasing levels of sophistication and detail
DEVELOPMENT Outline of a sheet material panel when it is laid flat
DEZINCIFICATION Loss of zinc, as a result of galvanic action, from copper-zinc alloys (such as brass), leaving porous copper
DIRECT [RELATIONSHIP] As linear relationship
DISCLOSURE The duty of the assured and his broker to tell the underwriter every material circumstance before acceptance of the risk
DISCONTINUITY Abrupt change in shape, such as at a notch, crack or internal corner, presenting a disruption to the lines of stress
DISBURSEMENTS Payments incurred for a variety of port expenses embracing fresh water, bunkers, customs fees etc
DISPLACEMENT The weight of water displaced by the ship
DOLPHIN A block or structure to which vessels secure
DOUBLE CHINE Hull possessing two chines per side
DOUBLE DIAGONAL System of wood construction in which layers of planking, separated by calico, are laid at 90 degrees to each other and at 45 degrees to the centerline
DOUBLE INFLECTION Curve having two bends; of S-form
DOUBLE SHEAR Shear involving two planes
DOWNWIND [SAILING] Sailing with the wind
DRAPE Ease with which fibre-based fabric, impregnated with uncured resin, can form around contours
DRAUGHT The depth of water at which the ship floats
DUCTILE Term describing a material that yields readily when drawn
DUNNAGE Materials of different types placed in the hold for the protection and separation of cargo
DURABLE Term describing wood that is resistant to decay; lesser resistance to decay is given by the categories: non-durable and moderate durable; while very durable indicates wood that is the most rot-proof
DURALUMIN [DURALUMINIUM] Copper-based
DYNAMICAL LOADINGS Loadings resulting from motion
EGG BOX [CONSTRUCTION] Type of construction involving multiple stiffners interlinked in cruciform fashion, broadly like an egg box
E-GLASS FIBRE Most commonly used type of glass fibre in GRP manufacture, the
E symbolizing electrical grade
ELASTIC LIMIT Maximum stress in a material at which the material will return to its original dimensions if the stress is removed
ELECTRIC ARC System of welding in which an arc is formed between a weld electrode and the metal to be joined, the electrode also serving as a filler rod
ELECTROLYTE Solution permitting the passage of ions in an electrical cell
END GRAIN BALSA Core material comprising panels of balsa sawn across the grain
ENDURANCE LIMIT Level of stress below which a material will not fail, regardless of the number of stress reversals
ENGINEERING TOWARDS FAILURE System of structural design in which the limit of acceptability is defined by failure
ENTERED SHIP A ship which has been entered for insurance in any Class of the Association
EPOXY [RESIN] Resin having relatively high strength, waterproofness, bonding and strain capability; made by condensing diphenylolpropane with epichlorhydrin, the hardener producing a rigid network of polymer molecules
EQUIVALENT TORQUE Expression, in the form only of torque, of the multiple loadings in a component experiencing principally torsion
ESTIMATED TOTAL CALL (ETC) The approximate level of premium which the Members will be advised how much to budget for the coming year
EVERGREEN Term describing a tree that does not shed its leaves
EXTRUSION Long length of a required section (which may be hollow), manufactured by a process in which a semi-molten billet of metal is pushed through a shaped die or former
FACE One or other of the outer layers of a sandwich panel (usually in fibre-resin composite)
FACTOR OF SAFETY Multiplier of the working load to indicate a design load
FACULTATIVE The right of option. The right of an underwriter to decide whether or not to accept a risk.
FAIL SAFE Design of a system so that the consequences of failure are relatively minor
FATHOM A unit of measurement
FATIGUE Reduction of strength of a material when subject to stress reversal
FATIGUE LIMIT An endurance limit
FEATHERED EDGE Sharp edge produced by a plain scarph
FEMALE MOULD Conventional mould inside which fibre-resin composite mouldings are laminated, producing a good quality exterior finish
FENDERS Rubbing pieces fitted on the sides of a ship as a means of protection
FERRIC OXIDE Oxide of iron; rust
FERRO-CEMENT CONSTRUCTION Construction comprising a steel framework and mortar
FIBREGLASS Term used historically to describe boats of GRP construction
FIBRE-RESIN COMPOSITE System comprising fibres (such as glass or carbon) in a solidified resin matrix
FORECASTLE The superstructure on the upper deck at the fore end of a ship
FORE PEAK The watertight compartment at the extreme foreward end
FREIGHT The hire of a ship, the carriage of cargo, cargo
GAFF-RIGGED Rig having a mainsail that is four-sided in profile, the upper edge being supported by a gaff that projects from the mast
GALLERY Aperture in a ballast keel which houses the nut that tightens a keel bolt
GALVANIC CORROSION Corrosion resulting from the close proximity of two different metals in the presence of an electrolyte
GALVANIC SERIES Rank ordering of metals depending upon their nobility
GANGWAY A ladder used for boarding a ship
GAP-FILLING Capability of an adhesive to bridge gaps in joints without noticeable loss of strength
GEL COAT Outer, unreinforced resin layer of a laminate provides waterproofing and decorative feel
GENERAL AVERAGE An extraordinary sacrifice or expenditure is intentionally and reasonably made or incurred for the common safety for the purpose of preserving from peril the property involved in a common adventure
GENERATORS Projection lines used to define the three-dimensional form of a panel (based typically upon a cone)
GLASS [FIBRE] Reinforcement fibre produced by drawing glass very finely
GLASS FIBRE CLOTH Fabric woven from yarns of glass fibre
GLASS-FIBRE-REINFORCED RESIN Composite of glass fibres in a resin matrix
GLASS-FIBRE TAPE Glass-fibre cloth, woven in narrow widths
GLOBAL LOADS Large-scale loads affecting the whole structure
GLUED CLINKER System of clinker construction in which the planks are glued rather than fastened together
GOOD FAITH A basic principle of insurance. The assured and his broker must disclose and truly represent every material circumstance to the underwriter before acceptance of the risk. A breach of good faith entitles the underwriter to avoid the contract.
GOOSENECK Hinge connecting the boom to the mast
GRAPHITE As carbon
GRAVEYARD TEST Method of measuring the durability of wood by burying samples in good soil and assessing the wood samples decay over a period of time
GREEN Term describing: 1. Resin in the early stages of curing. 2. Unseasoned wood
GROWN WOOD Wood selected for its curved grain to match individual structural components
GRP Abbreviation for glass fibre reinforced polyester, plastic or polymer
GUNWALE 1. Upper edge at the side of the hull. 2. Longitudinal at this position, usually for modern wood construction
HAGUE RULES Throughout the latter half of the 19th Century there was increasing dissatisfaction amongst cargo owners and their insurers with the law governing a carrier's liabilities for damage to goods in their custody. This was due to an increasing number of protection and other limitation clauses. There was a growing demand to establish a uniform code or rules for the carriage of goods by sea. After many years a conference was held at Brussels which resulted in a set of Rules known as the Hague Rules. The aim of the Rules was to establish a uniform code for the carriage of cargo shipped under Bills of Lading.
HAGUE VISBY RULES In 1968 the Hague Rules were revised and amended in order to bring them into line with the needs of a modern shipping industry. The amended Rules are known as the Hague Visby Rules.
HALF-BREADTH PLAN A drawing of the water-lines and sheerline of a hull from the centerline outwards
HAMBURG RULES A further convention on the Carriage of Goods By Sea was held in Hamburg and the provisions agreed at this convention are known as the Hamburg Rules. The Hamburg Rules make the presumption that the carrier is responsible for any loss or damage unless it is proved that the carrier took all measures that could reasonably be required to avoid the occurrence.
HANGING KNEE Knee disposed vertically
HARDENER Component added to epoxy resin which serves as part of the chemical reaction (unlike the catalyst added to polyester resin that initiates curing)
HARD SPOT Localized, stiffened area on the skin or sandwich of a hull that is less flexible than the surrounding panel
HARDWOOD Wood from broad-leaved trees (usually slow growing, thus producing compact,dense, hard wood)
HATCH COVER Steel, wood or canvas covers for the openings to cargo compartments
HEAD Height of a liquid (e.g., sea water), producing pressure
HEARTWOOD Wood inside the sap-wood of a tree, used for construction
HEAT-TREATABLE Term describing metals that respond to appropriate heat treatment with improved mechanical properties, especially strength
HELD COVERED A provisional acceptance of risk, subject to confirmation at a later date that the agreed cover is needed. Where applicable to an existing insurance, cover is conditional, in practice, on prompt advice to the underwriter as soon as the assured is aware of the circumstances to be held covered coming into effect
HEELING COUPLE Product of the force on the sails at the centre of effort (equal to the hydrodynamic force at the centre of lateral resistance) and the heeling lever
HEELING LEVER Perpendicular distance between the lines of the aerodynamic and hydrodynamic forces or, in rig analysis, between a heeling force at the hounds and the chainplate
HOG Centreline longitudinal of a wood dinghy or small cruiser
HOGGING Tendency for a hull to bend upwards in the middle
HOLDS Spaces below deck for stowage of cargo
HONEYCOMB CORE Sandwich core material (typically of aluminium alloy or aramid fibre paper), comprising hexagonal or other cells, their axes being through the thickness of the core
HOOKED SCARPH JOINT Wood joint between two structural members, not unlike a plain scarph, but zigzagged to lock the joint
HORN TIMBER Structural member running from the transom to the stern post on a countersterned craft
HOSE TEST The testing of hatch covers weather tight integrity through the application of a jet of water (minimum 5 bar) to the hatch joints
HOT MOULDING System used by Fairey Marine for moulding wood boats, involving large ovens to cure the adhesive bonding the veneer
HOUNDS Position on the mast at which the main shrouds and forestay meet
HULL A ships chassis/base frame
HYDRODYNAMIC Term relating to the behaviour of water (or other liquid) under conditions of motion
HYDROSTATIC Term describing an environment in which forces are produced by a static water head
IMPACT STRENGTH Strength of a material or structure under impact or sudden load
IN COLUMN Term describing a strut that is essentially straight such that end loads are transmitted without producing a tendency to curve
INDEMNITY Security against damage or loss, exemption from penalties, compensation for damage
INHERENT VICE A defect or inherent quality of the goods or their packing which of itself may contribute to their deterioration, injury, wastage or final destruction without any negligence
INSURABLE INTEREST It is illegal for anyone to insure without an insurable interest or, in the case of marine insurance, a reasonable expectation of acquiring such interest. In general one has such interest when his relationship to the property at risk may expose him to loss or liability or where he stands to gain by the safety of such property
INTERLAMINAR STRENGTH Strength between laminates of a fibre-resin composite, assessed by direct tension in a line perpendicular to the plane of the composite or by peeling laminates
INTERNATIONAL ORGANIZATION FOR STANDARDIZATION
International body concerned with the development of standards, such as technical standards for boat construction
ISOPHTHALIC [RESIN] Type of polyester resin, named after the isophthalic acid that this resin contains, which is mechanically superior and more waterproof than the commonly used orthophthalic polyester
ISOTROPIC Term describing a material that possesses mechanical properties which are essentially equal in all directions centreline
JURISDICTION Administration of justice
KEEL LINE Line along the keel, usually the centreline
KICKING STRAP System for pulling the boom downwards by using a line or wire attached to both boom and mast
KILN DRYING Seasoning of wood using ovens
KILOGRAM (KG) SI unit of mass (2.205lb)
KNEE Structural member used to brace the corners formed in a vessels construction
LAGGING Material used for insulation
LAID UP RETURNS P & I insurance premium or call which is paid back to a Member when a vessel is temporarily taken out of service
LAMINATE 1. Single layer of fibre-resin composite; 2. Complete fibre-resin composite; 3. Layered wood, glued together
LASER CUT System for cutting plywood and other materials using a numerically-controlled laser
LEECH Aft edge of a sail
LEEWARD Away from the wind
LENTICULAR ROD RIGGING Streamlined shrouds having a convex lens-shaped section
LETTER OF PROTEST A declaration by the Master holding another party responsible for some loss or damage that has already occurred or is likely to occur to the ship or cargo
LIABLE/LIABILITY Legally bound, subject to, exposed to, answerable for/being liable for
LIEN Retention of property until outstanding debt is discharged
LIGHTER An open non-propelled barge
LINE The amount or percentage in a broker's slip or policy which establishes the extent of the underwriter's liability. The written line is written by the underwriter on the slip when he accepts the risk
LINEAR [RELATIONSHIP] Relationship between two variables in which a percentage increase in one produces the same percentage increase in the other
LINEAR FOAM Ductile, but low strength, plastic foam that is non-cross-linked
LINES PLAN Drawing of the lines of a boat, depicting the shape of various cutting planes
LINER A merchant ship engaged on a scheduled direct regular service
LIP Squared-off section at each end of a scarph joint so that a feathered edge is avoided
LIST Inclination of ship from the upright position
LOG BOOK An official book containing the records of the voyage inserted by the Master of the ship
LLOYDS REGISTER RULES AND REGULATIONS Set of requirements developed by the classification society Lloyds for construction and equipment
LOCAL LOADING Loading occurring over a small area
LODGING KNEE Knee linking two horizontal structural members
LONGITUDINAL Stiffener (usually for the hull skin), running fore and aft
LONGITUDINAL STABILITY Stability in the fore and aft sense
LOOSE TENONS Rectangular-sectioned pieces of wood inserted into paired sockets in two components in order to prevent relative side movement
LOW-CARBON STEEL Steel having a carbon content up to about 0.15 per cent
LUFF Leading edge of a sail
MAIN BOILER Typically water tube boilers where the steam and water drums are interconnected with tubes which carry the water.
MAINSAIL Principal sail set on the after side of the main mast
MAINSHEET Rope system that controls the mainsail
MANHOLE A hole in the tank top to provide access
MANIFEST Inventory/list of cargo shipped
MASS Quantity of matter in a body, measured by its resistance to change of motion
MASTER A person in sole charge of a ship
MAST PILLAR Deck to keel support for a deck-stepped mast
MAST STEP Fitting into which the matching bottom of the mast fits
MATE'S RECEIPT An important document used in preparing bills of lading. It is a receipt, given and signed by the Mate, for goods actually received on board the ship. It must provide a description of the cargo, including the quantity, distinguishing marks, grade and any other relevant information
MECHANICAL LOSSES Energy losses within a mechanical system (such as result from the friction caused by rotating gears and bearings and the resistance produced by an alternator)
MEMBER A ship owner/charterer/time charterer or a person who hires ships for a specific voyage who has entered his vessels with a P&I Association for insurance cover
METALLIZING Spraying of molten zinc on to heated steel
MICRO-BALLOONS Very small, gas-filled plastic bubbles added to resin to provide a lightweight filler
MICRO-CRACKING Formation of fine cracks in a fibre-resin composite
MICRO-SPHERES As micro-balloons except that the bubbles are of glass
MIDSHIPS Middle of the ships length
MIG Acronym for metal inert gas welding, involving an electrical current between a mechanically-fed wire and the work piece, the weld being surrounded by an inert gas such as argon
MILD STEEL Steel in which the carbon content is less than about 0.8 per cent
MISREPRESENTATION A mis-statement of fact made by the assured or his broker to the undewriter, before acceptance of the risk, which misleads the underwriter in assessing the risk
MODEL Description of the behaviour of a system in words, mathematically or as a diagram, in order to study the relationship or process more easily
MODERN WOOD CONSTRUCTION Wood construction involving the extensive use of synthetic resin adhesives in favour of fastenings
MODULUS As Youngs modulus of elasticity
MODULUS OF RIGIDITY Measure of the stiffness of a material in shear
MOISTURE CONTENT Percentage of moisture contained within a sample of wood to the dry weight of the sample
MOMENT [OF A FORCE ABOUT A POINT] Product of the force and the perpendicular distance from the force to the point
MOMENTUM Product of the mass and the velocity of a moving body
MONOCOQUE Shell that is self-supporting and does not rely on framing or stiffeners
MORTAR Mix of cement and sharp sand (having angular grains that lock together)
MOULD Pattern from which a hull or another component can be built
MOULDED Type of construction, based upon a mould, involving: 1. A fibre-resin composite;2. Laminated wood veneers
MOVEMENT Change in the dimensions of wood with change in moisture content
MULTI-AXIAL [FABRIC] Fabric comprising multiple layers of glass or other fibre reinforcement with varied directional orientation
MULTI-CHINE Hull form possessing several chines
MULTI-CONICAL Hull panel design in sheet material based upon multiple cones having generators in common
MUTUAL INSURANCE The sharing of liabilities on a non profit basis
NEUTRAL AXIS Axis perpendicular to the bending forces (in the case of a beam) and passing through the centroid of the section
NEUTRAL SURFACE Surface or plane passing through the neutral axis of a beam at all sections along its length and thus remaining unchanged in length when bent
NEWTON (N) SI unit of force and weight; rigorously, the force required to accelerate a mass of 1kg by 1 m/s; equivalent to 4.45 lb force
NOBLE Indication of the relative tendency of metal to resist galvanic corrosion
NO CURE NO PAY Salvage provision whereby no award is paid to a salvor if he is unsuccessful
NODE Intersection, as where the structural members of a space-frame meet
NORMALIZE Process in which a metal is heated and cooled naturally
NUMERICAL CONTROL Approach in which components are shaped by machine from numerical data in the form of offsets
OFFSETS Co-ordinates of points defining a line
ONE-HUNDRED-YEAR-WAVE Wave of a height occurring on average once every hundred years
ONE-OFF Term describing the building of a single boat without intention for multiple production
ORTHOPHTHALIC [RESIN] Widely-used polyester resin, made by a combination of maleic and phthalic anhydrides with a glycol
ORTHOTROPIC As anisotropic
OSMOSIS Process in which water-soluble material in a fibre-resin composite draws water through micro-pores in the surface as a result of a pressure differential, resulting in entrapped cavities filled with contaminated water that then form blisters on the surface
OVERSPILL CALL If a claim exceeds the Clubs retention, the Pool's retention and excess loss reinsurance an overspill call will be required.
OWNER A person who owns a ship (shortened version of ship owner)
OXIDISE To combine with oxygen
PANEL 1. Area of hull skin bounded by elements of the framework; 2. Length of mast between supports (e.g., deck, shrouds, stays or spreaders)
PARABEAM [TRADE NAME] Form of sandwich construction in which the glass fibre faces are separated by pillars of glass fibres, the whole being impregnated with resin
PATCH Sail cloth reinforcement in the corner of a sail
PERISHABLE Description for wood of low durability
PEAK TANKS The compartments at the extreme ends of the ship which are normally used as ballast tanks
PERIL A term used in the Marine Insurance Act (1906) to denote a hazard
PHOSPHOR BRONZE Alloy of copper, tin and phosphorus
PILOT A person who aids the Master in ship navigation, usually in confined waters
PILOTAGE A charge raised on a vessel entering a river/port/estuary/canal where the services of a pilot are obligatory
PIN-ENDED [STRUT] A strut in which the ends force
PINNED Modelling of a space frame in which the structural members are regarded as being able to rotate freely relative to each other at the nodes
PLAIN SAWN Description for wood planks in which the annular growth rings run approximately across the width
PLANKING Lengths of wood that constitute the skin of a framed wood boat
PLANING CRAFT Craft that produce significant hydrodynamic lift at speed
PLASTIC Synthetic polymer that can be moulded while in an appropriate state
PLUG Full-sized model of a hull, deck, etc. from which a female mould can be produced
PLYWOOD Sheet material manufactured by gluing together layers of veneer with the grain running alternately along and across the sheet
POISSONS RATIO Ratio of a materials lateral contraction to longitudinal extension when subject to longitudinal stress
POLAR SECOND MOMENT OF AREA Measure of the resistance of a shaft to twisting as a function of its sectional shape
POLICY YEAR Time period of insurance
POLYACRYLOMTRILE Starting material for the manufacture (with pyrolysis) of carbon fibre
POLYESTER [RESIN] Type of thermoset, used extensively in the boat building industry for GRP construction
POLYETHYLENE Tough, translucent thermoplastic, best known under the trade name Polythene
POLYETHYLENE FIBRE Fibre produced from polyethylene, having good mechanical properties but a tendency to creep
POLYMER Compound made up of large molecules composed of many repeated simple units
POLYURETHANE Type of plastic used significantly for surface coatings, glues and foams
POLYVINYL CHLORIDE [PVC] Thermoplastic material produced by the polymerization of vinyl chloride
POOLING AGREEMENT Means or method whereby claims are paid by various contributions from P & I Clubs collectively known as the London Group or International Group. A sharing arrangement.
PORT Left hand side of the vessel when looking forward
POWER Rate of doing work or consuming energy, measured in watts (W)
PRE-IMPREGNATED MATERIALS [PRE-PREGS] Fibre- resin composite in which the precise amount of resin is incorporated in the reinforcement and is cured subsequently by heat only
PREMIUM Monies paid to a P&I Association in respect of the entered ship
PRESSURE Force per unit area, usually of a fluid
PRE-TENSIONING Tensioning a tie before any external load is applied
PRIMA FACIE At first glance
PRINCIPAL STRESSES The largest single stress representative of two or more individual stresses, simultaneously applied
PRIVITY Knowledge actual or constructive
PRODUCTION Construction of more than one boat to the same design and specification
PROFILE PLAN Drawing of the side view of a hull (usually with keel and rudder), depicting the sheer, keel, buttock and bow lines
PROOF STRESS Stress in a material at a particular value of percentage strain, applied where the yield point is indistinct
PROPELLER A revolving screw-like device that drives the ship through the water
PUMP A means of transporting liquids or gases from one area to another
QUARTER SAWN Description for wood planks in which the annular growth rings run perpendicular to the width
RADIAL Direction perpendicular to a trees annular growth rings, viewed in section
RADIAN Angular measure; formally , the angle subtended at the centre of a circle by an arc equal to the radius of the circle
RAKE [OF MAST] Lean of the mast in the fore and aft sense
RATIFY/RATIFICATION To confirm or accept by signature or other formality
REACHING Point of sailing with the wind abeam
RECOVERY Amount recovered from a third party responsible for a loss on which a claim has been paid.
RECREATIONAL CRAFT DIRECTIVE [RCD] European Union directive specifying a range of requirements with which boat builders must comply
REINFORCED PLASTIC Generally used term to describe a fibre-resin composite, normally GRP
REINSURANCE The procedure whereby an insurance company or P & I Club passes on all or part of the risk to another insurance company or P & I Club.
RELEASE CALL Upon the cesser of insurance in respect of an Entered Ship for any reason, or at any time thereafter the Managers may at their sole discretion demand an amount to release the Member from liability for further contributions to Calls in respect of such ship
RESERVE When claims cannot be met out of the call income or reinsurance then there are always reserves. It is not however a policy of P & I Clubs to hold on to their Members money unnecessarily and therefore reserves are maintained at an optimum level
RESIN 1. Name given to many polymers (e.g. synthetic adhesives, surface finishes and plastics); 2. Substance naturally exuded from trees
RESORCINOL FORMALDEHYDE Fully waterproof, two-component resin adhesive for wood
R-GLASS FIBRE Glass fibre possessing superior mechanical properties to E-glass fibre (and having a specification similar to the better known S-glass fibre, developed in the USA)
RIG Spars, sails, shrouds, stays and ropes of a sailing craft
RIGHTING COUPLE Product of the weight of a boat numerically (equal to the buoyancy) and the righting lever
RIGHTING LEVER Perpendicular distance between the lines of the forces given by the weight of the boat and the buoyancy
RIDER CLAUSE The addition of type-written clauses to the standard Charter Party. These clauses can significantly alter the owner's responsibility for cargo claims
RING FRAME Frame that runs continuously around the hull and deck
ROLL CENTRE Point about which a vessel rolls such that only rotational movement is apparent
RO-RO/ROLL ON/ROLL OFF Ships capable of shipping vehicular traffic via a ramp
ROTATIONAL MOULDING Moulding technique in which a female mould is coated with structural plastic by bi-axial rotation
ROVING Bundle of up to a hundred strands of reinforcement fibre (usually glass)
RULES Comprise of P & I cover/H & M cover/FD & D cover afforded to the Members subject to the terms of entry
RULING LINES As generators
RUNNING BACKSTAY Readily adjustable back-stay, usually running aft from the hounds or an intermediate position on the mast
RUNNING DOWN CLAUSE The collision liability clause which appears in a policy covering the hull and machinery of a ship
RUNNING DOWN CLAUSE/RDC COVER Sometimes all or part of the third party liability cover for damage caused to other vessels through collision is included in a special clause in the Hull and Machinery insurance. This is normally the only third party cover provided within the traditional Hull and Machinery policy
SACRIFICIAL ANODE Metal of low nobility (such as zinc) that will corrode, in the presence of sea water, in favour of other metals in the vicinity
SACRIFICIAL PROTECTION Means of reducing the extent of galvanic corrosion by placing a sacrificial anode on the hull underwater
SAGGING Tendency for a hull to bend downwards in the middle
SALVAGE Process of recovering a ship or cargo from a loss or damage due to maritime perils
SALVOR The person claiming and receiving salvage for having saved a vessel and cargo or any part thereof from impending peril or recovered after actual loss
SANDWICH CONSTRUCTION Construction involving faces (normally of fibre-resin composite) bonded to a lightweight core
SAPWOOD Wood just inside the bark of the tree, not suitable for construction because it lacks durability
SCARPH JOINT Tapered joint to connect two members of similar section
SCORE Portion of wood removed from a structural member (e.g. a beam shelf) to create a joint (e.g. a skewed dovetail)
SEAM Space between the planks of a carvel-built boat
SEASON Removal of natural moisture from green wood
SECOND MOMENT OF AREA Measure of the resistance of a beam or strut to bending or buckling as a result of the sectional shape
SECTION Plane considered perpendicular to the main axis (of a hull, beam or strut for instance)
SECTION MODULUS Ratio of the second moment of area of a section to the distance from the neutral axis to the outer surface of the section
SECURITY/GUARANTEE A promise by a P&I Association to make payment to the receiver of the guarantee should the Member be held liable for a claim
S-GLASS FIBRE Abbreviation for structural glass fibre; glass fibre having mechanical properties superior to E-glass fibre
SHACKLE Link to connect fibre and wire ropes to fittings, and for many other purposes
SHELL PLATING The plates forming the outer side of the hull
SHEAR Deformation in which two parallel planes remain parallel but move relative to each other
SHEAR PIN Easily replaced component (used with outboard engines) intended to shear when subject to abnormal loads, in order to avoid more extensive failure
SHEAR STRENGTH [OF A MATERIAL] Strength of a material in shear
SHEERLINE Line depicting the intersection of the deck and topsides at all points fore and aft
SHEET MATERIAL Constructional material available in sheet form (e.g. plywood and steel)
SHIPPER A person wishing to send his goods by sea
SHORT GRAIN Grain direction that does not run along the length, or follow the curve, of a wood member
SHROUD Means of providing athwartships support to a mast (usually in the form of wire rope)
SI Abbreviation for Systeme International dUnites, a standardization of units, based upon metric measurements
SINGLE CHINE Term describing a hull having one chine on each side
SINGLE SHEAR Shear involving a single plane
SKEG Structure projecting from the hull directly ahead of the rudder to provide support to the rudder and protect it
SKEWED DOVETAIL Specific joint used between the deck beams and beam shelf on craft of traditional wood construction
SKIN Outside covering (e.g. planking) of a hull
SKYLIGHT A framework over accommodation or engine with glass inserted to admit light and air to the space below
SLAMMING AREA Area of the hull subject to sea water impact in waves (mainly in the bow)
SLEEVED Term describing the reinforcement of an extrusion by sliding a length of slightly larger or smaller sectioned extrusion outside or inside the first
SNAPE Lip used for the stem to wood keel joint
S-N CURVE Graph describing the level of stress (S) that produces failure in a material when a sample has experienced a specific number (N) of stress reversals
SOFTWOOD Wood from the needle-leaved coniferous trees
SOLVENT-BASED Term describing surface finishes and adhesives that contain solvents (e.g. spirit-based rather than water)
SOUNDING PIPE A pipe led from the upper deck to the bottom of a tank which is used to ascertain the depth of water or liquid therein
SPACE-FRAMED CONSTRUCTION Construction based upon struts and ties
SPADE RUDDER Rudder not supported by a skeg
SPECIFIC MODULUS As specific stiffness
SPECIFIC STIFFNESS Stiffness of a material relative to its density
SPILE Process in which a board of wood is marked for cutting to fit a complicated shape (e.g. an adjoining carvel plank)
SPINNAKER POLE TRACK Track attached to the forward side of a yachts mast so that the spinnaker pole height can be varied
SPREADER Strut attached to the mast and used to spread the main shrouds
SPRUNG Process in which sheet material, especially metal plate, has been bent into place when within the materials elastic limit
STAINLESS STEEL Steel containing at least 11 per cent chromium (18 per cent being normal for marine use) to provide resistance to corrosion
STANCHION Vertical column supporting decks or girders, also called a pillar
STARBOARD The right hand side of a ship when looking forward
STATION Longitudinal location of a section of the hull
STAY Means of providing fore and aft support to a mast (usually in the form of wire rope)
STAYED Term describing a mast that is supported by shrouds and stays
STEAM BENT Term describing wood that has been steamed so that it bends more readily
STEERING GEAR The gear which turns the rudder and thus steers the vessel
STEM Forward constructional member where the hull sides meet at the bow
STERN The aftermost end of a ship
STERN POST Near vertical structural member at the aft end of the hull on which the rudder may be hung
STEVEDORE Docker engaged on cargo/baggage shipment
STIFFENER General term to describe structural members that support the skin or other unsupported constructional panels
STIFFNESS Measure of a materials resistance to strain, or a structures resistance to deformation
STITCH AND GLUE Method of construction in which plywood panels are first wired (or similar) together and fibre-glass-taped (with resin) on both sides of the corners to make the joints
STITCHED FABRICS Multiple layers of directional fibre reinforcement, stitched together, thus avoiding crimp
STOCK [OF RUDDER] Part of the rudder to which the blade is attached
STOPWATER Softwood dowel used at points in joints/ intended to swell and limit water ingress
STOW To put away, to stow cargo in a hold
STRAIN Amount of deformation relative to the extent of the material over which the deformation occurs; tensile strain is expressed as extension relative to original length
STRAIN ENERGY Energy transferred to a material and stored in the material when it is deformed
STRAND Bundle of about two hundred reinforcement fibres
STRAP KNEE/FLOOR Knee/floor constructed from metal
STRENGTH 1. Maximum stress a material can withstand; 2. Measure of the capability of a structure to withstand loads
STRESS Loading per unit area within a material
STRESS CONCENTRATION Localized high stress in a structure caused by a discontinuity of form
STRESS CONCENTRATION FACTOR Measure of the acuity of a stress concentration; ratio of the stress with and without the stress concentration
STRESS REVERSAL Change of stress in a material as a result of loading variation
STRIKES INSURANCE Insurance which reimburses the ship owner for his daily operating costs when his vessel is strike-bound as a result of either shore labour or crew disputes
STRINGER Longitudinal, usually of small section
STRIP PLANKING System for planking using edge-glued/ narrow, wood planks
STRUCTURAL EFFICIENCY Measure of the relative strength and stiffness of a structure or material for its weight
STRUCTURE Assembly of components (or a single component) intended to withstand loads
STRUT Structural member that is long relative to the size of the section, subject to compressive (end) loads that tend to cause buckling
STUD Fixing attached with some permanence to one component and tensioned by a nut after passing through another component
SUBROGATION The right of the underwriter to step into the shoes of the assured following payment of a claim to recover the payment from another party who was responsible for the loss. Limited to the amount paid on the policy
SUIT Legal proceedings
SUPERNUMERARY A relative of a crew member, or any other person whom a Member has agreed to maintain or carry on board an entered ship (except a person or persons carried on board an entered ship pursuant to a passage contract) including persons engaged under articles of agreement for nominal pay
SUPERSTRUCTURE Raised area above the deck, increasing interior headroom
TABERNACLE Structure mounted on the deck of some small yachts into which the mast is fitted, so enabling convenient lowering and raising
TACKLE Arrangement of rope running through blocks (pulleys) in order to haul a load greater than the pull on the rope
TACK WELDS Infrequent/ short welds made in order to hold two plates in position prior to welding the join fully
TAILSHAFT The aftermost length of shaft to which the propeller is attached
TAKE UP Absorption of water by a boat of traditional wood construction (causing swelling of the planking and the sealing of the seams)
TALLY The process of checking, or taking account of the goods placed into a ship or unloaded from a ship.
TANGENTIAL Direction along the annular growth rings with respect to the section of a tree
TANKER A steamer or motor vessel in which oils or molasses are transported in bulk
TARPAULIN Waterproof canvas cover secured over non-watertight hatch covers.
TENSION Nature of the load tending to stretch a structural member
THERMOPLASTIC Type of plastic that softens when warmed
THERMOSET Type of plastic that remains rigid once set and does not soften when warmed
THWART Athwartships seat in a small boat
TIE Tensile member
TIMBERS Steam-bent, small-sectioned frames
TIME BAR Expiry of suit time
TO CLASS Term describing the construction of a vessel so that it meets the requirements of one of the classification societies
TOGGLE Metal link (usually for attaching a bottlescrew to a chainplate)
TOGGLE PIN Pin (often termed a clevis pin) to provide attachment to a toggle
TOP HAT STIFFENER Stiffener used in fibre-resin composite construction, the section taking the form of a top hat
TOPSIDE Side of a vessel above the waterline
TORQUE Turning moment
TORQUE CURVE Graph depicting the torque produced by an engine at different rotational speeds
TORSIONAL Effect of torque on a component; twisting
TORT An injury or wrong independent of the contract as by assault, malicious prosecution, negligence, slander or trespass
TORTURED PLYWOOD METHOD Technique for design and construction in which plywood is forced to take up an element of compound curvature
TOVALOP A voluntary agreement but legally binding between tanker owners which provides compensation to third parties for pollution damage and clean-up costs
TRAMP A merchant ship not confined to definite ports, but sails when cargo is available to and from any port
TRANSHIPMENT Process of transferring cargo, usually from one ship to another
TRANSOM Flat, or slightly curved, structure extending across the stern of a hull
TRANSVERSE STABILITY Stability in the athwartships sense
TRI-AXIAL Term describing three-layered reinforcement fabric, each layer being oriented differently (typically at 0, 60 and 120 degrees)
TRICHLOROETHANE Agent of value for conditioning a surface prior to further laminating in order to achieve a good bond
TRIM The difference in draught forward and aft
TRUE LENGTH Actual length of a line in three-dimensional space
TRUSSED STRUCTURE Space-framed structure designed to support a load
T-SECTION Stiffener having a section in the shape of a T
TURBOCHARGER A performance enhancing device fitted to engines which use exhaust gases to drive gas turbines which force clean, cool air into the engine allowing increased power output from an engine.
TWEEN DECKS The space between two adjacent decks
ULLAGE The vertical distance between the surface of the liquid and the top or crown of the tank
ULTIMATE TENSILE STRENGTH [OF A MATERIAL] Tensile stress that produces failure in a sample of the material
UNA RIG Rig having a mainsail and no others
UNDERWRITER Has responsibility for negotiating each Member's calls required by the Club and the terms of entry to apply to new or additional vessels as well as any other changes that a Member might require. He is also heavily involved in marketing and development
UNIDIRECTIONAL [REINFORCEMENT] Term describing reinforcement possessing strength and stiffness, effectively in one direction only
UNSTAYED Term describing a mast that resists loads as a cantilever; possessing no shrouds or stays
UPWIND [SAILING] Sailing as close to the wind as possible
UREA FORMALDEHYDE Waterproof, two-component, resin adhesive for wood
URETHANE ACRYLATE Flexible adhesive for bonding the foam core to the outer face of a moulded sandwich
UTMOST GOOD FAITH Mutual trust in negotiating an insurance contract. A breach of good faith by one party entitles the other to avoid the contract.
VACUUM BAGGING Technique for consolidating fibre-resin composits (especially sandwich construction) and moulded wood veneer by removing most of the air from a bag surrounding the moulding
VECTOR Quantity defined by magnitude and direction
VECTOR DIAGRAM Depiction of the forces (assumed in equilibrium) as a node, expressed as vectors and arranged to form a complete diagram
VELOCITY RATIO Ratio of the distance the rope end of a tackle is pulled to the distance the load moves
VENEER Thin sheet of wood, either sliced tangentially or sawn radially from the log
VENTURE Term embracing the three elements of any commercial voyage - hull, cargo and freight/passengers
VINYL ESTER Resin having the characteristics of both epoxy and polyester resins
WARP Roving or yarn running along the length of a fabric
WARRANTY An undertaking by the assured whereby he promises to comply with the terms of the warranty. Non-compliance consitutes breach of warranty and the underwriter is discharged from liability as from the date of the breach
WASH DAMAGE Created when a ship's speed is excessive in narrow and confined waters. Wash created erodes the banks and damages property on the banks
WATERLINE Line along the hull of a boat at the surface of the water
WAYBILL List of passengers or inventory of cargo shipped
WEFT Roving or yarn crossing the warp of a fabric
WELD DISTORTION Distortion arising in the vicinity of a weld as a result of the localized, extreme heat
WELDED MESH Steel lattice welded at its intersections (thus providing a stronger reinforcement for ferro-cement construction than hitherto used chicken wire)
WELDING Technique for joining metals in which the edges to be joined are melted and fused, usually with like filler material
WELD PENETRATION Depth to which the metal to be joined is melted and fused when welding
WET OUT Impregnate fibre-reinforcement material with liquid resin
WINCHES Machinery with which a vessel can operate its mooring ropes and cargo wires which are drum driven by many means to tension/slack mooring ropes and wires
WIND Twist in a component
WINDWARD Towards the wind
WINDLASS The machine used for raising the anchor and chain cable
WITHOUT PREJUDICE Leaving the question open.
WOOD FLOOR Floor fashioned from grown wood or laminated to shape
WOOD KEEL Major part of the backbone of a yacht of traditional wood construction, running fore and aft between the sternpost and stem
WORKING LOAD Load to which a structure is subjected in normal conditions of use
WOVEN ROVINGS Rovings woven together to make a fabric
YARN Twisted strands of reinforcement fibre
YIELD STRENGTH [OF A MATERIAL] Minimum level of stress at which a material continues to deform with no increase in load
YOUNGS MODULUS OF ELASTICITY Measure of the stiffness of a material, defined by the ratio of stress to strain
