The Ultimate Guide to Tug Boats: Types, Functions, and Applications

The Ultimate Guide to Tug Boats Types, Functions, and Applications - Merchant Navy Info - Blog

A tugboat, or more commonly a tug boat, is an tug boat that assists in mooring or anchoring a vessel by towing or pushing the vessel toward a port. Tug boat are special vessels that help large ships enter and also leave ports. Tug boats can be used not only to tow ships toward ports but also to supply them with essential supplies such as water and air. Tugs are also essential for non-self-propelled barges, oil rigs, timber rafts, etc. Tractors are small but relatively powerful machines due to their sturdy construction. The main reason for their great power is also their propulsion system.

The ancillary functions of tugs and facilitation of the berthing process are listed below.

  1. Tug boat can be used as salvage boats and also icebreakers.
  2. Firefighting supplies can also be provided for ports and barges.
  3. These are the most important ships, acting as rescuers for ships in difficult times, such as in narrow channels or in bad weather.

Possible Uses of Tugs 

The uses and functions of tugs vary from port to port, as each port has different requirements and also intakes. It is common to see them pushing and towing megaboats and also barges. Their use depends on the following factors: 

  1. Port traffic, 
  2. Type of vessels this tug will operate on, 
  3. Navigational obstacles to be considered, 
  4. Environmental conditions, 
  5. Local laws and territories 
  6. Transportation by tugs 

Classification of Tugs Based on Purpose 

Based on purpose, they are used as offshore tugs. There are two types: 

1. Escort tugs: Tugs are generally designed to escort and steer ferries and barges to their destination. These are the so-called escort tugs.

2. Auxiliary tugs: These tugs provide support services for offshore and towing operations.

These tug boats play an important role in berthing operations. There are mainly three types of tugboats used in the marine industry: 

  1. Conventional tugs 
  2. Tractor tugs and 
  3. Azimuth sterndrive tugs 

1. Conventional Towing 

This is the towing that our company has been using since the beginning. They are manufactured according to the oldest known principles of tractor development. Although traditional tug boat are less maneuverable, they are still used in almost every port around the world. Due to technological advances, the tugboat is equipped with a diesel engine with one or more propellers. Single propeller tugs are divided into conventional right-handed and also conventional left-handed. Traditional right-handed tags are more common and used more frequently than left-handed tags. These are very reliable. 

Propeller Configurations used Screw Propeller 

In “traditional” tugs, the drive is usually diesel-powered. Propellers create thrust in the water and also affect the movement of the ship. The names of these tugs are based on the several propellers they contain.

  1. Single-shaft tug means a traditional propeller tug, 
  2. Double-shaft tug means a traditional two-propeller tug
  3. Three-shaft tug means his classic three-propeller tug.

2. Tractor Tag 

The key to the tractor is the use of a two-way drive unit. Some are like large rotating outboard motors, while others consist of rotating vertical blades. These allow the thrust units of the tugs to be placed more or less side by side under the bridge, allowing excellent right-hand maneuverability. The tow point can be moved closer to the stern to get maximum power from the power unit, so the thrust is always outside the tow point, creating some fun turning moments.

3. Azimuth Star Drive (ASD) Tugs 

These tugs are intermediate between conventional tugs and tugboats, as they utilize some of the advantages of both. Her two towing positions are possible, forward and amidships, and the main propulsion is provided by her two rotating azimuth units arranged similarly to a conventional twin-shaft tug.

Other Different Types of Tugs 

In addition to the above classification, some other different types of tugs are described as follows: 

1. Tractor 

Tugboat with Cycloid Propeller Before World War II, tugboats had high power ratings and large tonnage capacities. The propeller used was of the cycloid type to facilitate maneuverability. These were known as cycloid tags. The Voith-Schneider propeller (VSP) is a further development of the cycloid drive. It has excellent maneuverability and is also ideal for ferries and barges.

2. Carousel Tugboat 

The Dutch developed the carousel tugboat, which proved to be an award-winning maritime innovation in 2006. It consists of a coupled inner and also outer ring, the former connected to the vessel and the latter to the hull of the vessel’s tugboat, which is towed by a winch or hook.

3. Reverse Tractor 

A tractor is called a reverse tractor tractor if it has a rear-mounted drive unit with a Z drive. These reverse tractor tugs have no skeg and work efficiently when entrained. These tractors do not have flat skeg available, so they have fewer fatigue problems than tractor tractors. Generally, ASD tags function as reverse tags.

4. Combination Tag 

A conventional screw tag is equipped with a bow thruster and also a nozzle with steering to improve maneuverability. These modified tugs with additional equipment, such as engines and steering nozzles, are called “combi tugs.” Combi tractors are preferably retrofitted with conventional twin auger tractors to achieve maximum efficiency.


Two towing positions are possible: forward and amidships, and also the main propulsion is provided by two rotating azimuth units arranged like a conventional twin-shaft tug. The azimuth drive unit replaces traditional shafts and propellers and allows her to rotate 360 ​​degrees around a vertical axis.

6. Journo Tags 

Journo Tags are very stable and can function both as support and accompanying tags. This is a high-tech tug that allows remote control via VSAT or 4G connectivity. Its 360-degree turning and excellent evasive speed put it at the top of the tugboat standard ranking.

7. Eco tugs 

Tugs equipped with hybrid technology or LNG-fuelled tugs are classified as eco-tugs. These tugs serve the same escort and support purposes as conventional tugs but without damaging or polluting the marine ecosystem.

8. Ice Tug Boats 

These tugs accompany ferries and barges and act as icebreakers and salvage boats to get the ferries and barges to their destination faster. The world’s most powerful tugboat supplies supplies to the Swedish port of Luleå. But now, Gondan Shipyard is committed to building and delivering an ice-breaking tug that will probably earn the ticket to be the most powerful hybrid tug in the world. Robert Allan’s design was the basis for the construction of this tugboat. To support the vessel passing through difficult areas, a powerful hybrid propulsion system will be used, namely Wärtsilä’s HYTug propulsion system. It is a combination of the “Lloyd Register Class” and RAL TundRA’s 3600-H design.

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