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Ship Science and Engineering

Shipbuilding, Materials, Sea Trials, Retrofits and Recycling glossary

The industrial realization of the design and the lifecycle that follows: block and grand-block assembly, welding processes and non-destructive testing, hull steels (AH36, DH36), LNG containment materials, coatings under the PSPC, and cathodic protection. Covers speed trials under ISO 15016, maneuvering trials, retrofits (BWTS, scrubbers, EEXI, EPL), and end-of-life recycling under the Hong Kong Convention and the EU Ship Recycling Regulation with the IHM.

219 defined terms.

A

Acceptance trial
Owner's trial demonstrating contract performance.
Acoustic emission inspection
NDT method detecting active crack growth.
Active bandhandling
Material flow process in steel pre-processing line.
Adamite roll
Roll material used in plate mill, relevant to material supply.
Aft block (Block construction)
Stern blocks erected on building dock.
AH36 steel
Higher-tensile shipbuilding steel with min yield 355 MPa.
Air bubble lubrication (ABL)
Retrofittable Mitsubishi MALS-type system.
AluMaster
Aluminum block fabrication.
Aluminum 5083-H321
Marine-grade Al-Mg plate.
Anti-Fouling System (AFS Convention)
IMO 2001 Convention banning TBT.
Aqua-blasting
Wet-abrasive cleaning of hull steel.
Arrival condition (sea trial)
Standard loading condition for trial.

B

Backing strip welding
Single-sided weld with backing bar.
Ballast Water Management System (BWMS)
Type-approved per MEPC.300(72) BWMS Code.
Bilge block (drydock)
Side support for hull on docking.
Block coefficient verification (sea trial)
Light-condition draft survey.
Block erection schedule
Master plan for joining hull blocks.
Boiler hydrostatic test
Pressure test at 1.5x MAWP.
Brackets (structural)
Connection plates between primary members.
Building berth
Inclined slipway for ship launching.
Building dock
Drydock used for new construction.
Built-up girder
Welded plate girder primary structure.
Bulb flat profile
HP standard stiffener cross section.
Butt weld
Weld joining two plates in the same plane.

C

Cargo gear test
SWL proof load test of cranes and derricks.
Carry-over (rolling)
Rolling defect in plate production.
Cathodic protection (ICCP)
Impressed current cathodic protection per IMO Res. A.798(19).
CCS (China Classification Society)
Member of IACS.
CE marking (recreational craft)
EU recreational craft directive marking.
CEM III/B cement
Marine concrete binder used in caissons.
Charpy V-notch test
Impact toughness test per ISO 148-1.
Class notations (DNV, ABS, etc.)
Symbols denoting service and special features.
CO2 laser cutting
Plate cutting method in shipyard.
Coastal Class society
Domestic recognized organization.
Coating Technical File (CTF)
PSPC documentation per MSC.215(82).
Cofferdam (construction)
Temporary watertight enclosure during repair.
Common Structural Rules (CSR-BC&OT)
Harmonized class rules.
Container lashing test
Trial of lashing/twistlock components.
Containment system (LNGC)
Membrane GTT Mark III/NO96 or Moss spherical.
Continuous welding
Welding without break across panel.
Conversion (FPSO)
Tanker conversion to floating production unit.
Corrosion margin
Allowance added to net thickness per class rules.
Crane proof load test
1.25x SWL for cranes per ILO C152.

D

Deadweight survey (sea trial)
Draft survey verifying lightship weight.
Detailed design
Production design phase.
DH36 steel
Higher-tensile steel with -20 °C Charpy.
Direct calculation method
FE-based strength check per class.
Distortion control
Welding sequence/jigs to limit deformation.
Dock trial (basin trial)
Pre-sea trial conducted alongside.
DP capability plot
Sea trial output for DP class.
DPST (Drydock Period for Special Survey)
5-yearly class major dock.
Drag chains (launching)
Chains to limit launch travel.
Dry-dock interval
5-year class survey cycle.
DST (dynamic shock test)
Shock trial for naval ships.

E

EEXI Technical File
Required documentation per MEPC.333(76).
EH36 steel
HT steel with -40 °C Charpy.
Electromagnetic gauge (UT)
EMAT ultrasonic thickness gauging.
End-of-life ship (EoL)
Vessel destined for recycling.
Engine commissioning
Final tests of installed engine in yard.
Erection joint
Block-to-block weld during erection.
EU Ship Recycling Regulation (EU SRR 1257/2013)
EU regulation on recycling.
Eulerian-Lagrangian welding analysis
FE method for residual stresses.
Exhaust Gas Cleaning System (EGCS)
Open/closed-loop scrubber retrofit.
Extension trial
Additional sea trial after retrofit.

F

Fabrication tolerance
Allowable deviation per IACS Rec. 47.
Fatigue Class S-N curve
Stress-cycle curve used in fatigue assessment.
Final inspection (yard)
Pre-handover inspection.
Fire Control Plan
Required under SOLAS II-2/15.
First-of-class trial
Extended sea trial for lead ship.
Fixed Fire Detection and Alarm System (FDAS)
Type-approved system per FSS Code.
Flange-stiffener
Built-up T-bar stiffener used in primary structure.
Flat panel line
Robotic line for fabricating flat hull panels.
Float-out
Operation removing hull from drydock.
Forecastle block
Fwd-most block of the hull.
Friction stir welding
Solid-state welding of Al panels.
Fume scrubber (yard)
Welding fume extraction system.

G

Galvanic anode
Zinc/aluminum anode per ASTM B418/F1182.
Gas-free certificate
Certificate before hot work in tanks.
General arrangement (GA)
Top-level layout plan.
GoaGoa
Specific shipyard reference, omitted.
Goal-Based Standards (GBS)
IMO Res. MSC.296(87) for bulk and tankers.
Goose neck
Vent terminal shape for tanks.
GTT Mark III Flex+
Membrane containment with stainless primary.
GTT NO96 system
Membrane LNG containment with Invar primary barrier.

H

Half-block model
Yard wooden model historically used for fairing.
Hand-over protocol
Set of documents at delivery.
Hardness test (HV/HB)
Vickers or Brinell hardness check.
Hazardous Materials Inventory (IHM)
HKC/EU SRR mandated IHM Part I.
Heat-affected zone (HAZ)
Region of microstructural change near weld.
High-Velocity Oxy-Fuel (HVOF) coating
Thermal-spray coating for shafts.
Hold ladder test
Drop test of vertical ladders.
Hong Kong Convention (HKC)
2009 Hong Kong Convention on Ship Recycling (in force 26 June 2025).
Horizontal pressure test
Tank hydrostatic test.
Hot work permit
Yard/onboard permit before welding/cutting.
Hover-craft skirt material
PVC-coated polyester used in ACV refit.
Hull cleaning robot
Crawler underwater hull cleaning unit.
Hull stress monitoring system (HSMS)
Strain gauges on deck, used at trial.
Hybrid laser-arc welding
Combined laser+MAG welding.

I

IACS Common Structural Rules
Harmonized rules for bulkers/tankers.
IACS Rec. 47
Shipbuilding and repair quality standard.
IACS UR W11
Hull steel grade requirements.
IACS UR Z23
Bilge keel arrangement.
ICCP system
Impressed current cathodic protection.
IGS Aug 2014 retrofit
Inert gas retrofit on chemical tankers.
IHM Part I/II/III
Inventory of Hazardous Materials sections.
Inclining experiment
Test determining KG per IS Code 2008.
Indicator power trial
Engine indicator diagram during trial.
Inert gas system test
Trial of IG composition and flow.
Installation manual
Manufacturer document used during retrofit.
Intermediate Survey
Class survey between Special Surveys.
Invar (36% Ni)
Low-CTE alloy used in LNG membrane tanks.
ISO 15016
Sea trial speed/power correction procedure.
ISO 19030-2
Hull/propeller performance default method.
ISO 23800
Voyage data recording standard.

J

Jacking system (load-out)
Hydraulic jacks for SPMT load-out.
Jigs and fixtures
Tooling supporting block fabrication.
JIS G3106 SM41B
Japanese mild ship steel grade.

K

K-line bilge keel
Standard bilge keel arrangement.
Keel laying
Symbolic placement of first block in dock.
Kockums system
Yard panel-line system originally Swedish.

L

Laser cutting (CO2/fiber)
Plate cutting method.
Lashing equipment certification
GL/DNV approved twistlocks.
Launch (gravity, side, float)
Methods of launching the new hull.
Lay-up (long-term)
Owner-initiated preservation regime.
LCS welding consumable
Low-hydrogen weld metal for HT steel.
LHV gas heater
Component of LNG fuel system on retrofit.
Liner offset class
Class-approved liner allowance.
Lloyd's Register IHM Expert
LR service for IHM compliance.
Load test (cargo gear)
Cargo gear proof load.
Lock-up valve test
System safety device test.

M

MARC welding wire
Common GMAW wire used in yards.
Margin plate
Plate at the edge of double bottom.
MEPC.1/Circ.815
Guidelines for using ISO 15016 in EEDI verification.
MIG/MAG welding
Gas metal arc welding processes.
Mock-up unit
Full-scale mock-up for piping/cabling rehearsals.
Module assembly area
Yard area for outfitting modules.
MRBM (membrane LNG)
Membrane containment system component.

N

9% Nickel steel
ASTM A553 plate for LNG/liquid hydrogen tanks.
NACE MR0175 (sour service)
Material standard relevant to FPSO retrofit.
NDT (Non-Destructive Testing)
UT, MT, PT, RT, VT methods.
NK steel grade KA32
ClassNK ship plate grade.
NORSOK M-501
Surface preparation/coating standard.

O

Oily Water Separator retrofit
Compliance upgrade to 15 ppm spec.
One-side welding (FCB)
Flux-copper backing single-sided welding.
Operational sea trial
Charter-acceptance trial.
Outfitting platform
Yard area for hull outfitting.
Overflow pipe test
Cargo overflow alarm test.

P

Paint surveyor (NACE Level III)
Coating inspector certification.
Panel line
Robotic panel fabrication line.
Performance Standard for Protective Coatings (PSPC)
IMO Res. MSC.215(82).
PetroBras P-class FPSO
Conversion reference projects.
Plate edge preparation
Bevel preparation for welding.
Plate seam
Longitudinal plate joint.
Polar Code modifications
Retrofit modifications for Polar Code compliance.
Pre-erection joint
Joining of two blocks before main erection.
Pre-outfitting
Outfitting before block erection.
Pre-trial inspection
Yard checks before sea trial.
Pressure test (tank)
Air/hydrostatic tank tightness test.
Production design
Detailed design for fabrication.
Progressive trial
Speed/power runs at increasing speed.

Q

Quality Acceptance Standard (Yard)
IACS Rec. 47-based standard.
Quenched and tempered steel
Heat-treated steel for high-strength service.

R

Radiographic Testing (RT)
NDT method using X-rays.
Recycling Facility Plan (SRFP)
Ship Recycling Facility Plan per HKC.
Refrigeration retrofit
Conversion from R22 to R134a/R744.
Repair specification
Owner-issued repair scope document.
Repair Yard Stations
Categorization of repair yards.
Residual stress measurement
X-ray diffraction or hole-drilling.
Riding sea margin
Sea-trial speed allowance.
Robotic welding
Robot arms used in panel lines.
Routine survey (PSC)
Port State inspection at port call.
Rudder horn
Structural rudder support cast or fabricated.
Rudder stock
Forged shaft transmitting rudder torque.

S

Sandblasting (Sa 2.5)
Surface preparation standard ISO 8501-1.
Schettino plot (sea trial)
Synonymous with course recorder trace.
Scrubber retrofit
Installation of EGCS.
Sea trial measurement plan (STMP)
Plan per ISO 15016.
Self-elevating pontoon
Jack-up vessel used during construction.
Sequential block welding
Procedure to control distortion.
Shaft alignment optical
Pre-erection alignment of shafting.
Shielded Metal Arc Welding (SMAW)
Stick welding.
Ship Recycling Facility (SRF) authorization
EU SRR list authorization.
Ship Recycling Plan (SRP)
Required per HKC and EU SRR per ship.
Side launching
Launch transverse to keel.
SOLAS Ch. II-1/3-2
PSPC requirements.
Special Survey (SS)
5-yearly class survey.
SPMT (Self-Propelled Modular Transporter)
Heavy load mover for block transport.
Standard speed trial
Mile run on measured mile per ISO 15016.
Steel plate (ASTM A131)
Common ship plate spec.
Steel-cutting ceremony
Yard milestone of cutting first plate.
Submerged Arc Welding (SAW)
High-deposition welding for plates.
Surface preparation grade Sa 3
White metal blast standard.

T

Tank-top doubler
Doubler plate at column footings.
Test loading condition
Trial loading for inclining experiment.
Thermal spray aluminum (TSA)
Coating for offshore structures.
Three-dimensional measurement
Photogrammetry for hull alignment.
Towing convoy (delivery)
Wet/dry tow for newbuild delivery.
Trial trip
Builder's sea trial.
Two-component epoxy paint
PSPC-compliant ballast tank coating.

U

UKHO ENC (yard)
Charts used during sea trial.
Ultrasonic Testing (UT)
NDT thickness and flaw detection.
Underwater hull inspection (UWILD)
In-water survey in lieu of drydocking.
Universal Mill Plate
Plate rolled with controlled edges.
Urea storage tank (SCR retrofit)
New tank for SCR installation.

V

Vacuum testing (tightness)
Box test for fillet welds.
Verisys ECDIS test set
Type-approval data set.
Vibration acceptance test
ISO 6954 measurement at trial.
Visual Inspection (VT)
Welder visual inspection per ISO 17637.
Voith Schneider retrofit
VSP installation on tugs.

W

Wave height correction (ISO 15016)
Sea-trial speed correction.
Weldability test (CTOD)
Crack tip opening displacement test.
Welding consumables (E7018)
SMAW low-hydrogen electrode.
Welding Procedure Specification (WPS)
Approved welding procedure.
WPQ test
Welder performance qualification per ISO 9606-1.
Wreck removal
Operations under Nairobi Convention.

X

X-ray radiography
Standard volumetric NDT method.

Y

Yard inclining test
Builder's inclining experiment.
YS (yield strength) marking
Plate identification of yield grade.

Z

Zinc-rich primer
Anti-corrosion primer for steel.

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