Page 191 - DMGT546_INTERNATIONAL_TRADE_PROCEDURE_AND_DOCUMENTATION

International Trade Procedures and Documentation

Notes So there is gap between the wheel flanges and running edges of the rails, nearly equal to 1 cm.
(3/8") on either side. Normally, the tread of wheels is absolutely dead centre of the head of the
rail, as the wheel is coned to keep it in this position automatically. These wheels are coned at a
slope of 1 in 20.
The advantages of coning of wheels are:

1. Tilting of rail results in uniform wear of the head of the rail.
2. Proper gauge is maintained.
3. Life of sleeper and rail is increased.
Disadvantages of coning of wheels are:
1. The horizontal thrust tends to turn the rail outwardly. Sometimes, this results in the
increase in the gauge distance.
2. Sleepers under the outer edge of the rail are likely to get damaged. This effect is reduced
either by having ‘ADZING’ of sleepers or by providing inclined base plate. According to
American Practice, reducing the slope from 1 in 20 to 1 in 40 reduces the wear on rails.

8.3.3 Maritime Transport

Seaways/waterways are the oldest mode of transport. When goods are transported through the
water medium by a ship, it is called seaways transportation. Due to globalization of the world
market, seaways have a large potential for foreign trade. Throughout the world, this mode has
acquired a very high position due to its advantages like being the cheapest, having a larger
capacity and flexibility. But, the greatest drawback of it lies in terms of slow speed.

The main advantage of water transportation is the capacity to move extremely large shipments.
Water transport employs two types of vessels. Deep-water vessels, which are generally designed
for ocean and great lakes use, are restricted to deep-water ports for access. In contrast, diesel-
towed barges, which generally operate on rivers and canals, have considerably more flexibility.
Water transport ranks between rail and motor carrier in respect to fixed cost. Although water
carriers must develop and operate their own terminals, the right-of-way is developed and
maintained by the government and results in moderate fixed costs compared to rail and highway.
The main disadvantages of water transport are the limited range of operation and speed. Unless
the origin and destination of the movement are adjacent to a waterway, supplemental haul by
rail or truck is required. The capability of water to carry large tonnage at low variable cost
places this mode of transport in demand when low freight rates are desired and speed of transit
is a secondary consideration.
Typical inland water freight includes mining and basic bulk commodities such as chemicals,
cement, and selected agricultural products. In addition to the restrictions of navigable waterways,
terminal facilities for bulk and dry cargo storage and load-unload devices limit the flexibility of
water transport. Labour restrictions on loading and unloading at docks create operational
problems and tend to reduce the potential range of available traffic. Finally, a highly competitive
situation has developed between railroads and inland water carriers in areas where parallel
routes exist.
Main maritime routes are composed of oceans, coasts, seas, lakes, rivers and channels. But, maritime
circulation takes place on specific parts of the maritime space. The Atlantic Ocean is very important
since it accounts for 78% of the global trade, 68% of its value and 75% of the maritime trade. The
construction of channels and dredging operations are the attempts to facilitate maritime circulation
by reducing discontinuity. Water transportation is generally divided into inland waterways (rivers,
canals, lakes); domestic coastways and seaways. Water transport is generally used for high bulk,

186 LOVELY PROFESSIONAL UNIVERSITY