Extended Operational and Trade Vocabulary

Harbour Tugs, Towage Operators and Tug Builders glossary

Vocabulary of harbour and ocean towage: tug classification rules and notations, azimuth-stern-drive and rotor-tug designs such as the Robert Allan ART, dual-role anchor-handling tugs, the major towage operators including Svitzer and captive port fleets, and the builders like Damen and the bollard-pull and assist-method terminology of ship-handling tugs.

262 defined terms.

Showing 250 on this page (page 1 of 2).

A

ABS Guide for Building and Classing Tugs: American Bureau of Shipping classification rules covering hull scantlings, machinery and stability for harbour and ocean tugs.
Adani Ports Tugs: Captive harbour tug fleet operated by Adani Ports and SEZ Ltd across Mundra, Hazira, Dhamra, Krishnapatnam and other Indian terminals.
Adsteam Marine: Former Australian towage major acquired by Svitzer in 2007, which doubled Svitzer's global footprint overnight.
AHTS Dual-Role Tug: Anchor Handling Tug Supply vessel configured to perform both offshore anchor work and harbour assist, common in West African and Caspian ports.
Alphons-Type Tug: Compact Dutch-style harbour tug built by Damen and Padmos for inland and small-port operations.
ART (Advanced Rotor Tug): Robert Allan Ltd tug design with three Z-drives, two forward and one aft, jointly developed with KOTUG for very high indirect bollard pull.
ART 100-42: Larger Advanced Rotor Tug at 42 m and circa 100 t bollard pull deployed for LNG escort work.
ART 80-32: Specific ART variant with 32 m length and roughly 80 t static bollard pull, used by KOTUG SMIT Towage Canada.
ASD (Azimuth Stern Drive): Tug configuration with two azimuth thrusters at the stern and the towing point forward.
ASD 2810: Damen Azimuth Stern Drive tug, 28.67 m long with about 60 t bollard pull, the bestselling Damen tug platform.
ASD 2810 Hybrid: Damen's hybrid-electric variant of the ASD 2810 with battery banks and shaft generators.
ASD 3212: Damen 32 m ASD tug rated at about 80 t bollard pull, widely used in LNG terminals.
ASD 3213: Damen 32 m, 13 m beam ASD tug delivering circa 85 t bollard pull, popular with Boluda and Svitzer.
ASD 3413: Damen 34 m ASD tug rated circa 90 t bollard pull, frequently fitted with FiFi 1 notation.
ASD 4012: Damen 40 m ASD tug pushing into the 100 t bollard pull bracket for large container terminals.
ASD 5050: Damen escort tug class engineered for circa 130 t static bollard pull.
Astilleros Armon: Spanish shipbuilder in Asturias known for ocean-going tugs and offshore vessels.
Astilleros Gondan: Spanish private yard at Figueras building tugs, ferries, and offshore support vessels.
Astilleros Zamakona: Basque yard at Bilbao and Las Palmas building tugs, fishing vessels, and patrol craft.

B

Berg MTA 627: Mechanical thruster azimuth unit commonly fitted to mid-size ASD tugs.
Berg Propulsion: Swedish manufacturer of controllable pitch propellers, transverse thrusters, and propulsion control systems, owned by Caterpillar.
Bisso Towboat Company: New Orleans based US towage operator working the lower Mississippi.
Bollard Pull (BP): Static pulling force a tug can exert on a stationary load, measured in tonnes.
Bollard Pull Trial: Controlled test in which a tug pulls against a load cell anchored to a quayside bollard.
Boluda France: French arm of Boluda Towage formed from the Les Abeilles harbour business acquisition in 2018.
Boluda Towage: International towage group based in Valencia, Spain, active in Europe, West Africa, the Americas, and the Middle East.
Bow Tug: The tug made fast forward on a ship, typically working in indirect or transverse mode to steer the bow.
Brake Horsepower (BHP): Engine power measured at the flywheel, used historically to size tug main engines before BP became the headline figure.
Briggs Marine: Burntisland based marine services contractor offering subsea cable repair and aids to navigation work to offshore wind clients.
Bugsier-Reederei: Hamburg-based German towage and salvage operator with operations across North Sea and Baltic ports.
Bukser og Berging: Norwegian towage company headquartered in Oslo providing harbor, escort, and ocean towage services.

C

Caley Ocean Systems: Glasgow-based supplier of render-recover towing winches widely fitted to escort tugs.
Carrousel Tug: Novatug concept with a winch mounted on a rotating ring around the superstructure, allowing 360 degree towline lead.
Caterpillar 3508: 8-cylinder marine diesel offering up to about 970 kW, used in smaller harbour tugs.
Caterpillar 3512C: 12-cylinder Cat marine engine in the 1,300 to 1,765 kW range, a workhorse for medium ASD tugs.
Caterpillar 3516C: 16-cylinder Cat marine engine delivering up to about 2,525 kW, common in 80 to 100 t BP harbour tugs.
Caterpillar 3516E: Newer Tier 4 capable variant of the 3516 platform with higher output and reduced NOx.
Caterpillar Marine: Caterpillar Inc. division supplying marine engines, generator sets and propulsion packages to most major tug builders.
Cheoy Lee Shipyards: Hong Kong shipbuilder constructing Robert Allan and other tug designs.
China Tug Group: Informal collective term for China Merchants Port towage subsidiaries operating across Shenzhen, Shanghai and other mainland ports.
Coastal Petroleum Pilipinas: Philippine company providing harbour and offshore tug services at Subic and other ports.
Cochin Shipyard: Indian state shipbuilder at Kochi, builder of the aircraft carrier INS Vikrant.
Conoship International: Dutch naval architecture firm with tug and small workboat designs to its name.
Conventional Tug: Tug with fixed propellers and rudders at the stern, towing point forward.
Cory Brothers Tugs: Historic British harbour towage operation absorbed into larger groups in the late 20th century.
Cummins KTA38-M: 38-litre V12 marine diesel used in smaller workboats and inland tugs.

D

Damen ASD Tug: Family of Azimuth Stern Drive harbour tugs built to series-production at Damen yards in the Netherlands, Vietnam, China and Romania.
Damen RSD 2513: 25 m, 13 m beam RSD tug with about 70 t BP and a single wheelhouse working over twin bows.
Damen RSD 2513 Triton: Triton-class variant of the RSD 2513 with optimized hull aft.
Damen RSD 2914: 29 m RSD tug pushing into the 80 t BP bracket with FiFi 1 capability.
Damen RSD Tug: Reverse Stern Drive concept with double-ended hull and thrusters forward, allowing identical performance in either direction.
Damen Shipyards Group: Dutch shipbuilder, major supplier of ASD, RSD, ATD, and Stan Tug series.
Damen Song Cam: Vietnamese Damen yard near Haiphong, a key production site for the ASD 2810 series.
Damen Stan Tug: Long-running Damen series of small to medium conventional and ASD workboats and tugs.
Damen Stan Tug 1606: 16 m Stan tug with about 18 t BP, used in small ports and inland.
Damen Stan Tug 2208: 22 m Stan tug delivering circa 30 t BP for medium ports.
Damen Stan Tug 2608: 26 m, 30 to 40 t BP twin-screw harbour tug.
Damen TSD 2909: 29 m TSD tug at around 50 t BP, used as a more economical alternative to ASD designs.
Damen TSD 3211: 32 m TSD tug producing about 65 t BP for medium-port assist work.
Damen TSD 3315: 33 m TSD tug developed for assist and short-coastal towage.
Damen TSD Tug: Twin Screw Drive tug series with two ducted propellers and high-lift rudders.
Detyens Shipyards: South Carolina ship repair yard at the former Charleston Naval Shipyard with multiple drydocks for commercial and government work.
Direct Towage Mode: Operating mode in which the tug's bollard pull is applied in line with the towline.
Donjon Marine: US east coast salvage contractor with OPA 90 OSRO standing.

E

East Coast Tugs: Generic term for harbour towage operators along the US East Coast such as McAllister and Moran.
EDDY Mark II: Refined EDDY design with a single underwater pivot tower.
EDDY Tug: Robert Allan design with a thruster ring placed amidships within a moonpool, eliminating heeling moment during indirect work.
Engineering Office Hartmann: German naval architecture firm with several towage clients.
Eregli Shipyard: Turkish builder of RAmparts and ASD tugs for Mediterranean operators.
Escort Notation: Class notation indicating that a tug is certified for high-speed escort towage of tankers.
Escort Tug: High-performance tug providing braking/steering escort to laden tankers.

F

Fairplay 33: Damen ASD 2810 type tug typical of the Fairplay harbour fleet.
Fairplay Towage: German towage operator headquartered in Hamburg with operations across European ports.
FiFi 1 NSPS: Fire-fighting notation requiring deck water spray system protection alongside FiFi 1.
FiFi-1: IMO/class fire-fighting notation requiring at least 2,400 cubic meters per hour total monitor capacity.
FiFi-2: Notation requiring at least 7,200 cubic meters per hour total monitor capacity.
FiFi-3: Notation requiring at least 9,600 cubic meters per hour total monitor capacity.
Forward Tug Propulsion: General term for tugs with the working propulsion ahead of midships, including tractor and RSD designs.
Foss Maritime: US Pacific Northwest tug and barge operator founded in 1889 in Tacoma, Washington.
Fukushima Shipbuilding: Japanese yard delivering harbour tugs to local port operators.

G

G and H Towing: Galveston-Houston harbour towage operator.
Gellatly Hankey: Historic British towage agent name still seen in some legacy port records.
General Towing of New York: Early-20th-century harbour towage firm in New York Bay.
Glosten: Seattle-based naval architecture and marine engineering firm with extensive tug and ATB design experience.
Gondan: Asturian Spanish shipyard delivering RAstar escort tugs.
GPS Marine: London Thames harbour and barge towage operator.
Gulf Coast Tugs: Collective term for harbour towage operators in US Gulf ports such as Crescent, Bisso and G and H.

H

Halul Offshore Services: Qatar-based operator with harbour and offshore tug fleet.
Hamilton Marine Group: Niagara-region tug operator on the Great Lakes.
Harbour tug: Conventional or ASD tug serving port.
Henry Abeille: Historic French ocean salvage tug name still active in the Les Abeilles fleet under Boluda.
Heyser Towing: Baltimore harbour towage operator.
Hijos de J. Barreras: Vigo shipyard which has delivered tugs for Iberian operators.
Hold-Back Force: Force a tug applies to slow a vessel, separate from the steering force in escort work.
Hong Lam Marine: Singapore licensed bunker supplier operating one of the larger MPA accredited barge fleets.
HYDREX: Belgian underwater hull repair group, often supporting tug-assist operations.

I

IMCA Tug Guidelines: International Marine Contractors Association guidance covering towage operations during offshore moves.
IMO Tug Master Endorsement: STCW VI training certifications for masters of tugs above defined sizes.
Indirect Mode Steering Force: Lateral force certified in the escort notation, typically reported at 8 and 10 knots.
Indirect Towage Mode: Escort mode in which the tug uses its hull as a hydrofoil to generate steering force, often exceeding static bollard pull.
Inland Tug: Tug optimized for river and canal work, generally shallow draft and lower BP than coastal harbour tugs.
Iskes Cees: Damen-built ASD tug in the Iskes fleet at IJmuiden.
Iskes Towage and Salvage: Dutch family-owned towage and salvage operator based in IJmuiden.

J

Jansen JDX2: Render-recover towing winch design fitted to several European escort tugs.
Japan Marine United: Shipyard active in offshore wind support vessel construction for the Japanese market.
JSC United Shipbuilding Corporation: Russian state shipbuilder whose yards produce harbour tugs for Rosmorport.

K

Kamome Propeller: Japanese controllable pitch propeller and Z-peller manufacturer.
Kawasaki Heavy Industries: Japanese shipbuilder with a history of constructing Moss-type LNG carriers.
Keppel Singmarine: Singapore shipyard within Keppel that has built numerous RAL design tugs.
Keppel Smit Towage: Singapore-based joint venture providing harbor towage in Southeast Asia.
Khalifa Port Tugs: Captive AD Ports Group towage fleet at Khalifa Port, Abu Dhabi.
KORT nozzle: Accelerating ducted-propeller nozzle.
KOTUG: Dutch towage company operating harbor, ocean, and emergency response tugs.
Kotug Canada: Canadian harbor towage operator within the Kotug group.
KOTUG International: Dutch towage group operating in Europe and other regions.
Kotug Smit Towage: Joint venture between Kotug and Smit acquired by Boluda Towage in 2019.
Kraljevica Shipyard: Croatian builder that produced a series of escort tugs to RAL designs.

L

La Naval Sestao: Basque shipyard that has built large escort tugs.
Lamnalco: International integrated marine services provider with bases in the Middle East and Africa.
Larsen and Toubro Shipbuilding: Indian builder of ASD and conventional tugs for Indian ports and navy.
Les Abeilles International: International salvage and ocean towage subsidiary of the Les Abeilles group.
Lloyd's Register Tug Notation: LR's Tug Tug A1 notation covering structural and operational standards for towage units.
LR Escort 1: Lloyd's Register's lower escort notation rating tug for indirect work to defined limits.
LR Escort 2: Lloyd's Register's higher escort notation requiring more stringent escort performance demonstration.

M

Maersk Towage: Pre-Svitzer brand name for Maersk's towage activities before the 2001 rebrand.
McAllister Towing: US East Coast harbor towage operator.
McKenzie Marine: Smaller Canadian harbour tug operator on the St. Lawrence.
Med Marine: Turkish shipyard and tug operator based in Istanbul.
Mediterranean Shipping Tugs: Generic for harbour towage at large Med transshipment ports like Gioia Tauro and Piraeus.
Meriaura Group: Finnish marine operator with small tug fleet.
Metal Shark: Louisiana builder of pilot boats and small workboats including harbour tugs.
Moran Towing: US East Coast towage operator founded in 1860 in New York City.
MTU 12V4000 M63L: Rolls-Royce Power Systems marine diesel rated up to about 1,500 kW, used in mid-size tugs.
MTU 12V4000 M65L: Higher-output 12V4000 variant pushing past 1,700 kW.
MTU 16V4000 M53: 16-cylinder MTU marine diesel offering about 2,000 kW, common in 80 t class tugs.
MTU 16V4000 M63: 16-cylinder variant up to circa 2,240 kW with EPA Tier 2.
MTU 16V4000 M65L: Tier 4 capable 16V4000 derivative with up to about 2,560 kW.
MTU 16V4000 M73L: Top-rated 16V4000 with up to 2,880 kW.
MTU 4000 series: High-speed four-stroke engines.
Multraship Towage and Salvage: Dutch operator based at Terneuzen with about 30 harbour and salvage tugs.
MV Janus: First Carrousel Rave tug built by Multraship.

N

Naval Architects Glosten: See Glosten.
Newport News Shipbuilding: Huntington Ingalls yard at Newport News, Virginia, builder of US Navy aircraft carriers and submarines.
Niigata Power Systems: Japanese builder of medium-speed marine main and auxiliary engines for coastal and ocean-going vessels.
Niigata Z-Peller: Azimuthing propulsion unit.
Nippon Sharyo: Japanese builder with historical tug production.
Norwegian Coastal Tugs: Generic term for harbour tugs operated by Bukser og Berging, BOA and Bukser og Berging subsidiaries.
Novatug: Dutch developer of the Carrousel Rave Tug concept with Voith Schneider propulsion.

O

Ocean Group: Quebec-based Canadian tug and salvage operator, working St. Lawrence and Eastern Canadian ports.
Offshore Heavy Transport Tug: Larger ocean tug, outside core harbour scope but often dual-roled by operators like SAAM and Boluda.
OST (Ocean Service Tug): Generic IMO-related term for a tug capable of unrestricted ocean service.
Ostansjo Varv: Small Swedish builder of harbour tugs and workboats.

P

P and O Maritime Logistics: Broader DP World marine services brand encompassing P and O Maritime Services towage.
P and O Maritime Services: Dubai-headquartered DP World subsidiary providing harbour towage and offshore services across the Middle East, Africa and Australia.
Padmos Stellendam: Dutch builder of small workboats and harbour tugs.
PaxOcean: Singapore yard, part of Kuok Group, building harbour and offshore tugs.
Pilbara Marine Pilots Tugs: Captive harbour tug operations at Port Hedland and Dampier supporting iron ore export.
POSH (PACC Offshore Services Holdings): Singapore offshore and harbour services operator including POSH Semco brand.
Posh Semco: Singapore-based marine services brand offering offshore and emergency response services.
Posh Terasea: POSH-Terasea joint venture for ocean towage, complementing harbour fleets.
Pressure-Lubricated Z-Drive: Modern azimuth thruster with full pressure oil lubrication, replacing splash designs.
Prysmian Cable Tugs: Specialist tugs supporting cable lay vessels, sometimes provided by harbour operators.
Purvis Marine: Sault Ste. Marie based Great Lakes tug operator.

Q

QMI Tugs: Quality Marine Inc. type designation rarely used outside North America.
Quad Z-Drive Tug: Tug with four Z-drives, very rare configuration explored in some compact designs.

R

RAL (Robert Allan Ltd): Vancouver naval architecture firm founded 1930, the world's leading tug design house.
RAmpage: Robert Allan Ltd tug design for compact harbor and terminal operations.
RAmpage 5000: 50 m RAmpage tug with up to about 130 t BP.
RAmparts: Robert Allan Ltd series of ASD harbor tugs widely built in shipyards worldwide.
RAmparts 2400: 24 m Robert Allan ASD ship-handling tug class.
RAmparts 2500: 25 m RAmparts variant with circa 70 t BP.
RAmparts 3200: 32 m RAmparts ASD with about 80 t BP.
RAmparts 3400: 34 m RAmparts ASD with about 85 to 95 t BP, widely built in Turkey and India.
RApport: Robert Allan ASD tug design.
RAstar: Robert Allan Ltd escort and harbor tug series featuring a sponsoned hull form.
RAstar 3200: 32 m Robert Allan escort tug design with hard chine sponson hull.
RAstar 3400: 34 m RAstar escort tug.
RAstar 3600: 36 m RAstar escort tug.
RAstar 4000: 40 m Robert Allan escort tug design with high escort steering forces.
RAve: Robert Allan Ltd Advanced Rotor Tug ART design designation.
Reverse Tractor Tug: Tug operated stern-first when working, opposite of an ASD configuration.
Robert Allan Ltd Towmaster: Internal design tool used by RAL for towage performance simulation.
Robert Allan Vancouver Office: RAL's Vancouver British Columbia headquarters and principal design center.
Rolls-Royce Marine: Marine equipment division (now Kongsberg Maritime) producing steering gear and propulsion equipment.
Rolls-Royce US 205: Z-drive azimuth thruster commonly fitted to escort and ASD tugs (now Kongsberg US 205).
Rolls-Royce US 255: Larger Z-drive thruster for high BP escort tugs.
Roodzant Reederij: Smaller Dutch harbour towage operator.
Rotor Tug: Multi-thruster tug design developed under the Kooren and Kotug brands featuring three azimuth thrusters.
Russian River Tugs: Generic term for Volga-Don and Yenisei river towage operators.

S

SAAM Smit Towage: Former joint venture between SAAM and Smit, fully consolidated into SAAM Towage in 2019.
Saam Towage: Latin American and North American towage division of Chilean Sociedad Matriz SAAM.
Sanmar Bogacay: Series of RAmparts 2400 tugs built by Sanmar for global export.
Sanmar Shipyards: Turkish shipyard building Robert Allan licensed designs.
Sanmar Tundra: Series of RAstar escort tugs built by Sanmar.
Schottel: thruster manufacturer used on tugs and self-propelled barges.
Schottel Pump Jet: Hull-mounted pump-jet thruster from Schottel, used on harbor craft and offshore vessels.
Schottel Rudderpropeller (SRP): Schottel's Z-drive azimuth thruster family.
Schottel SRP 1212: SRP for larger ASD tugs in the 70 to 80 t BP class.
Schottel SRP 1515: Compact SRP unit for small workboats.
Schottel SRP 360: Older SRP designation common on 1970s tractor tugs.
Schottel SRP 4000 FP: Higher-input SRP for 80+ t BP escort tugs.
Schottel SRP 460: Mid-range SRP suited to circa 50 t BP tugs.
Schottel SRP 510: SRP rated for circa 1,800 kW input, used in 60 to 70 t BP tugs.
Schottel SRP-Tug: Generic term for any ASD tug propelled by Schottel SRP units.
Sembcorp Marine: Singaporean offshore and shipbuilding group with Tuas Boulevard Yard.
Shipyard Conoship Groningen: Dutch yard formerly building small Conoship-designed tugs.
Sietas Werft: Hamburg yard that built coastal and harbour craft including tugs.
Singapore Harbour Tugs: Captive harbour fleets at Singapore operated by PSA Marine, Keppel Smit and others.
Smit (Boskalis): Dutch towage and salvage brand acquired by Royal Boskalis Westminster in 2010, integrated into Boskalis Salvage and Towage divisions.
Smit Lloyd: Former Smit subsidiary in offshore towage.
Smit Rotterdam: Long-established Dutch salvage and towage brand originating in the mid-19th century.
Span Gear: Bridle arrangement on tow lines for distributing load.
Stan Tug 1606: See Damen Stan Tug 1606.
Stan Tug 2208: See Damen Stan Tug 2208.
Static Bollard Pull: Bollard pull measured under steady-state conditions during a witnessed trial.
Steerprop: Finnish azimuth thruster manufacturer, part of Rolls-Royce/Kongsberg ecosystem, used in some heavy tugs.
Stretching Tow Line: Synthetic high-modulus line such as Dyneema or polyester used between tug and ship to reduce shock loads.
Suez Canal Tugs: Captive fleet of the Suez Canal Authority assisting transits and stranding responses.
Svitzer: Towage operator and subsidiary of A.P. Moller-Maersk, headquartered in Copenhagen.
Svitzer Americas: Regional Svitzer business covering Americas harbour towage.
Svitzer Australia: Svitzer's Australian harbour towage business serving multiple capital ports.
Svitzer Europe: Svitzer's European business unit covering UK, Scandinavia, Iberia and Baltic.
Svitzer Hermod: Pioneering Carrousel Rave-style tug operated by Svitzer.

T

Tractor Tug: High-maneuver tug using Voith Schneider or ASD propulsion.
Transverse Arrest Mode: Escort braking mode with tug perpendicular to the ship's heading, dragging hydrodynamic load.
Tsuneishi Shipbuilding: Japanese yard at Fukuyama, bulk carrier specialist.
Tug Master Endorsement: STCW supplemental certification for masters of higher-power tugs.
Tug Notation T: ABS class notation T for tugs, indicating compliance with the tug Guide.
Tundra-Class: Sanmar-built RAstar escort tugs in the Tundra naming series.
Tutaja: Latin American towage operator working at Brazilian ports.

U

Uljanik Shipyard: Croatian builder which has produced a few tug newbuilds.
Underwater Foil: Generic term for hydrofoil lifting surfaces, surface-piercing or fully submerged.
Universal Tugs Services (URS): West African harbour towage operator working ports such as Lagos, Lome and Cotonou.
US 205 FP: Rolls-Royce/Kongsberg azimuth thruster, often paired in 60 to 80 t BP ASD tugs.
US 305 FP: Higher rated Rolls-Royce/Kongsberg thruster for large escort tugs.

V

Vahterus Marine: Finnish marine engineering supplier focused on heat exchanger systems aboard tugs.
VEKA Group: Dutch builder of inland waterway and small seagoing tonnage.
Voith Roll Stabilization (VRSTAB): Active roll-damping system derived from VSP technology used on some larger tugs.
Voith Water Tractor (VWT): Tractor tug with two VSP units forward and a skeg aft.
Voith-Schneider propeller (VSP): Cycloidal vertical-axis propeller.

W

Wartsila 6L20: 6-cylinder marine medium-speed engine rated up to about 1,200 kW for tugs.
Wartsila 8L20: 8-cylinder Wartsila medium-speed engine reaching about 1,600 kW.
Wartsila 8L26: 8-cylinder W26 engine up to about 2,720 kW for larger escort tugs.
Wartsila WTT: Wartsila Tug Technology naming used for some integrated propulsion offerings.
Wijnne Barends: Groningen-based MPP operator within the Spliethoff group.
Williamson and Cassidy: Historic UK towage firm absorbed into modern groups.
Wilson Sons Tugs: Brazil's largest harbour towage operator running over 80 tugs from Manaus to Rio Grande.
Winch Render-Recover: Active towing winch mode that pays out and hauls in line to keep load within set limits.
Workboat Tug: Smaller dual-role tug used for general harbour duties beyond ship assist.

X

XL Tug: Marketing term used by some operators for extra-large escort tugs above 90 t BP.