The type of merchant vessel employed on a trade route is mainly determined by the traffic carried. There are roughly three main divisions: liners, tramps and specialized vessels, such as tankers.
On occasion, and in particular when merchant vessels in one division are underemployed, a ship may be transferred to another division. For example, a tramp may be put on a liner berth to compete for liner cargoes. Conversely, liners may at times carry tramp cargoes, either as full or part cargoes.
Since the 1990s there has been a trend towards the development of the multi-purpose vessel and the combined transport system. Need for the multi-multi-purpose vessel has arisen to combat trade fluctuations and to enable the vessel to be more flexible in operation. Not only can the vessel vary the cargo mixture capacity on a particular voyage, but also she can switch from one trade to another. Such tonnage, although more expensive to build, should decrease the volume of laid-up tonnage. Examples of multi-purpose tonnage are found particularly in the vehicular ferry and container vessel and an increasing number of combination bulk cargo vessels, including tramp vessels.
A further significant factor is the growing emphasis on quick port turn-round time, the development of logistics and rising standards in ship management and a range of the IMO regulatory measures. This has been manifest in tankers, LNG, container tonnage and a whole range of types of ships. An example of a new range of vessels is the fast ferry. A description of each division follows.
Today, developing countries are taking an increasing share of the world’s manufacturing output consequent on the accelerating trend for relocation from high cost to low cost countries. This in turn has lengthened average transport distances for many manufactured articles; and since most of this international transport of raw materials and manufactured goods is by ship, some of it ‘added value’, demand for shipping services has increased (Tables 1.1 and 1.2). Hence there is a growing shift from European tonnage ownership to Asian countries (Tables 1.4 and 1.5).
4.2 Liners
These are vessels that ply on a regular scheduled service between groups of ports. Readers should note that it is this function, and not the size or speed, which defines the liner. Liner services offer cargo space to all shippers who require them. They sail on scheduled dates, irrespective of whether they are full or not. Hence in liner operation the regular scheduled service is the basis of this particular division, and it is vitally important to the shipowner that everything is done to ensure punctual sailing and arrival dates, otherwise company prestige quickly declines. Liner operation involves an adequately sized fleet and a fairly large shore establishment. Today the modern liner cargo service is multi-modal and is sophisticated in terms of its logistics and computerized operations. Liner companies are continuously striving to improve efficiency and reduce overall transit times to stimulate trade development and improvement in market share. The liner company therefore tends to be a large concern and in more recent years it operates its container tonnage on a consortia basis. However, there still remains in service a very small volume of ’tween-deck break-bulk cargo vessels, particularly in the subcontinent, Orient area, the developing countries and Eastern bloc markets. These vessels are being phased out and displaced by container tonnage, a growing proportion of which is multi-purpose.
The cargo liner operation today falls into several distinct divisions. It is characterized by a regular all year round service operating on a fixed route to ports situated in different countries. It conveys general cargo in a container or trailer/truck or as break bulk (loose cargo). The vessel sails whether she is full or not. The development of combined transport also involves inland distribution by road/rail through the use of a combined transport bill of lading involving a through-rate door-to-door from warehouse to warehouse. Each type is designed to achieve fast turnround times and a high level of ship man -agement efficiency. Vessels are completely integrated into the seaport operation which involves purpose-built berths and extensive port and inland infrastructure (see Chapter 17), and include container tonnage, ro/ro passenger (road haulage unit/motorist/passenger), ro/ro container, ro/ro other cargo, general cargo/passenger, general cargo single-deck, general cargo multi-deck, and general cargo/container. The container and ro/ro tonnage make up the prime growth sectors as countries worldwide develop their seaports and land freight links to accept this efficient and reliable unitized method of global distribution. Much of the container tonnage is integrated into the seaport’s overland rail distribution network. Increasing amounts of liner cargo in all categories of tonnage are being customs cleared inland and away from the former traditional seaport area, and greater proportions of a port’s infrastructure operation is now computerized. The era of the global logistics supply chain is fast developing, involving the hub and spoke system. Moreover, decline of the liner conference network has resulted in a new breed of liner management which focuses on door-to-door transit, the supplier to consumer, embracing 54 Ships, cargoes, trades and future trends
combined transport, and not as hitherto seaport to seaport transit. Overall the operation is high-tech, with continuous monitoring/tracking of the container throughout its transit.
4.3 Tramps
The tramp, or general trader as she is often called, does not operate on a fixed sailing schedule, but merely trades in all parts of the world in search of cargo, primarily bulk cargo. Such cargoes include steel, coal, grain, timber, sugar, ores, fertilizers, copra, etc., which are carried in complete shiploads. Many of the cargoes are seasonal. The tramp companies are much smaller than their liner cargo counterparts, and their business demands an intimate knowledge of market conditions. In recent years the family tramp business has merged with like-minded family tramp businesses to raise capital for new/second-hand tonnage and because of this have become more efficient in operation and in ship management. Many tramp businesses are adopting a third party ship management strategy, especially in manning, ship survey, bunkering and insurance.
Tramps are an unspecialized type of vessel, with two to six holds, each having large unobstructed hatches. They are primarily designed for the conveyance of bulk cargoes. Some ships are built with special facilities particularly suitable to the five main tramp trades: grain, coal, bauxite, phosphates and iron ore. The modern tramp vessel has a speed of 14/15 knots.
The bulk carrier (Figure 4.1) is designed with a single-deck hull which includes an arrangement of topside ballast tanks and holds specially designed for the bulk carriage of various types of loose dry cargo of a homogeneous nature. This includes grain, coal and iron ore. The cargo handling mode may be lift on or lift off to and from the holds by way of weather deck hatches, or alternatively by use of specialized shore-based equipment. Various features may include (a) hopper tanks – which may be combined with topside tanks, (b) strengthening for the carriage of heavy cargo (including ore), (c) holds equipped for the carriage of containers – container securing arrangements – or for the carriage of vehicles – hoistable vehicle decks accessed by way of sheet side doors, (d) weather deck equipped with stanchions for the carriage of logs, (e) self-discharging apparatus, including hopper-shaped holds and in-hold conveyer belts, (f) and design restraints and service restrictions pertaining to operations on the Great Lakes of North America.
An analysis of the bulk carrier world fleet and new building orders comparison is given in Table 4.1. The family tramp operator tends to manage the smaller capacity vessel and, with a limited range of multipurpose shipboard facilities, concentrates on the five bulk homogeneous tramp trades.
To raise safety standards in the bulk carrier tonnage and take advantage of new technology, the IMO revised SOLAS Chapter XII adopted by the MSC79 in December 2004 and which became mandatory in July 2006. This revision concerned those damage stability requirements applicable to bulk carriers, Tramps 55
Figure 4.1Bulk carrier, a ship designed with a single-deck hull, which includes an arrangement of topside ballast tanks and holds specifically designed for the bulk carriage of various types of loose dry cargo of a homogeneous nature. The cargo handling mode may be lift on/lift off to and from the holds by way of weather deck hatches or, alternatively, by way of specialized shore-based equipment. Various features may include: hopper side tanks (which may be combined with the topside tanks); strengthening for the carriage of heavy cargo (including ore); holds equipped for the carriage of containers (container securing arrangements) or for the carriage of vehicles (hoistable vehicle decks, accessed by way of shell side doors); weather deck equipped with stanchions for the carriage of logs; self-discharging apparatus, including hopper-shaped holds, in-hold conveyor belts and a self-unloading boom; design restraints and service restrictions pertaining to operation on the Great Lakes of North America. Related types include: wood chip carrier; cement carrier, with no weather deck hatches, but pumping; piping arrangements for the loading and unloading of cement; ore carrier, two longitudinal bulkheads, side tanks, ore carried in centre holds only; Ore/Bulk/Oil carrier (OBO), a bulk carrier with the additional facilities for the alternative (but not simultaneous) bulk carriage of oil; ore/oil carrier, an ore carrier with additional facilities for alternative (but not simultaneous) bulk carriage of oil.
especially concerning their structural strength. It also included an enhanced programme of inspections of bulk carriers which came into force in January 2007.
Further types of bulk carrier include the cement carrier without weather deck hatches but which has pumping and piping arrangements for the loading and unloading of cement. Numbers of this type of vessel are in decline because of displacement by containerized shipment. The ore carrier has two longitudinal bulkheads, and side tanks, one of which is carried in the centre holds only.
An example of a modern flexible container/bulk carrier ship is found in Figure 4.2. It has eight holds and a deadweight tonnage of 45,500 with a Tramps 57 Table 4.1 Bulk carrier fleet (world tonnage on order, 2000–11)
Average
Thousands vessel size
Beginning of month of dwt Ships (dwt)a
December 2000 31,208 486 64,214
% of total, December 2011 55.4 33.1
Source: Compiled by the UNCTAD Secretariat, on the basis of data supplied by IHS Fairplay.
Reproduced with the kind permission of UNCTAD Secretariat.
Note: aSeagoing propelled merchant ships of 100 GT and above.
Figure 4.2Combi King 45 flexible container/bulk carrier. This vessel, of 45,000 dwt, has a grain capacity of 58,700 m3 or a container capacity of 2,127 TEU. It is suitable for worldwide trading in the bulk carriage of grain, coal, ore, bauxite, phosphates, packaged timber, standard pipe lengths and containers. Source: Reproduced by kind permission of British Shipbuilders Ltd.
draught of 12.2 m. The service speed is 14 knots and the ship’s overall length is 194.30 m. The cargo hold grain capacity is 58,700 m3. Container capacity totals 2,127 TEUs of which 1,069 TEUs are above deck. It has one single 25 tons and two twin 25 tons electro-hydraulic deck cranes all fitted with grabs.
The crew accommodation complement is 25, of which 9 are officers. The vessel is suitable for worldwide trading in the bulk carriage of grain, coal, ore, bauxite, phosphates, packaged timber, standard pipe lengths and containers. The vessel is called the Combi King 45 flexible container/bulk carrier.
Tramp vessels are engaged under a document called a charter party, on a time or voyage basis. The role of the tramp vessel market continues to change.
The tramp operator tends to buy second-hand tonnage and the Greeks remain strong in the market. The trend to have long-term time charters of five to 10 years’ duration is becoming more popular.