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Unformatted text preview: Transport Technology Objective of these introductory lectures This series of lectures will show the wide variety of topics within Transport Technology and their relevance for the society. The coherence between the various elements with transport technology is presented in Figure 1. The first principles for the conceptual design of transportation and handling systems are presented, with applications for transhipment terminals (general cargo, air freight, containers). Transportsystem Infrastructure Transportequipment Logistics (= flow control) Physical Process Organisation Information (ICT) Organisation Planning Equipment Control • vehicles (road, rail) • handling equipment • dredging equipment Operations Systems approach Main topics of the lectures Figure 1 Coherence between elements of transportsystems All major equipment types are mentioned and some of them are discussed in more detail (road vehicles, dredging equipment, handling equipment). Furthermore one lecture presents a general approach for the design of transportation equipment, which can be applied for many equipment types in the field of mechanical engineering. The importance of standardisation is projected onto the application of load units and related design methodology. Some drive line characteristics and basic calculation methods are presented as every piece of equipment is provided with one or more drives in order to fulfil the required functionality (related to the movement of passengers and/or cargo). 1 Energy consumption and some approaches to energy-savings in the field of transport technology are mentioned and finally some considerations about mechanisation and automation of transport systems are presented. The lectures cover indeed a wide variety of topics on an introductory level. However, this is the nature of transport technology: creating systems and equipment for the movement of persons and goods, an outspoken activity for mechanical engineers. Delft, 3 October, 2001 Prof.ir. J.C. Rijsenbrij 2 Transport Technology An indispensable component of modern society Prof.ir. J.C. Rijsenbrij 1. Introduction The transportation of goods emerged when mankind started living in communities and goods had to be distributed over the various communities members (food, fur, building materials like forest products, clay and stones). The development of cultures resulted in transportation of raw materials over longer distances (with the help of animals like mules, elephants and small vessels see Figure 1) and later trade lanes connected a number of cultures. Trade enabled the separation of production and consumption area’s and so transportation developed not only for the collection of raw materials but also for finished products, both for living (food, pottery) and ostentation (show). For thousands of years men, animals, vessels and carts where the only means of transportation. Figure 1 Cargo vessels in Egyptian culture 1 Handling techniques (as a key-element for transport technology) were developed when mankind tried to move goods much heavier than himself. The inheritance of ancient cultures shows many ingenious approaches to handle the stone blocks for pyramids, the menhirs in England, France and Portugal and large stone monuments in South-Pacific isles. Religion was the major driver behind these impressive activities, only allowed through the support of transport technology. Already thousands of years, sea transportation is the dominant mode of transport and ports developed not only as places for the transhipment of goods, but also as centre where goods were stored, refined, processed and traded. Many cities developed from an early transhipment place into a large industrialised living centre. It is amazing how many tools and techniques were developed in the last 1000 years, to support the handling of goods both for the transportation of consumer goods and for the transportation of building materials, raw materials etc. (see Figure 2). Figure 2 Handling equipment in the Middle-Ages The industrial revolution of the 19th century generated rail transportation, which further supported a separation of production and consumption centres. The speed of transportation (so far determined by sailboat, towboat and mail-coach) increased fivefold. In the beginning of the 20th century the arrival of automobiles and trucks 2 contributed to better services for the transportation of (smaller) goods and after the second world-war air cargo transportation emerged, mainly for the transport for time critical (high-value) products. Nowadays transportation is an indispensable component of our society. Globalisation could develop through the support of low- cost, high-frequent transportation between almost every place in the world. Transportation really developed as a utility in our society. In an USA-study (“vision 2050”) the attitude to transportation concluded: “Transportation is the foundation of our entire economy and quality of life”. The following major modes for the transportation of cargo can be recognised. Sea transportation Large-scale vessels are provided mainly for the carriage of raw materials (ore, coal, crude oil etc.). Special designs are used for half or finished products (refinery products, cement, forest products, perishable goods etc.) and many half products and consumer goods are transported into maritime containers on container vessels in size varying from 1000 tons DWT (100 TEU) until 100.000 tons DWT (8000 TEU). One TEU is the space-equivalent of one twenty foot container (20’ x 8’ x8’6” # 6.05 x 2,44 x 2,59 m) and vessels are designed with a carrying capacity for an average of 912 metric tons per TEU (see Figure 3). Figure 3 Container arrangement in Post-Panamax container vessel 3 The vessel sizes are determined by the trades, their volumes and economies and a number of “natural” barriers such as the waterdepth of ports and entrance channels, the maximum allowed sizes through Panama canal and Suez canal, the passing height of bridges (Bridge of the Americas in Panama, Verrezano bridge New York). For some commodities special vessel designs are applied such as reefer vessels for fruit (citrus, banana’s etc), roll-on/roll-off vessels for trucks and trailers, self-discharging vessels for ore and coal etc. Coastal services have been in use for thousands of years and will continue to be important as increasing concerns about the environment and congestion on road an rail infrastructure will support a revival of coastal services with smaller specialised vessels (500-5000 DWT). Transportation speeds for seagoing cargo vessels vary from 12 knots (12 nautical miles/hour) to 25 knots (45 km/hr). Barge transportation For many centuries barges (with sails or towed by men or animals) carried cargo over rivers, inland lakes and (man-made) canals, supporting the developments in trade and industrialisation alongside these inland waterways. Nowadays motorbarges carry up to 2000 ton of cargo and the towing of barges is almost entirely replaced by pushconvoys (aver. 4, max. 6 barges in Europe, Figure 4) with sometimes more than 50 barges of ± 3000 tons cargo each in one convoy on the rivers Mississippi/Missouri. Transportation speeds are only about 20 km/hr., but the large carrying capacity, the limited environmental impact and the service-approach of barge-operators makes barge transportation attractive, even for inland container transportation. Figure 4 Push-barge convoy in Europe (4 barges) 4 Rail transportation As from the middle of the 19th century rail transportation was developed firstly for passengers later for cargo (e.g. supporting the mid- and far-west developments in the USA). The one and a half-century of developments have not been very dramatically. Axle load limitations (because of the sleeper-supported track and wheel loads) and restrictions for shunting yards resulted in max. train length’s of about 700 m. in Europe and cargo train speeds of 120-140 km/hr. In the USA and Australia much longer trains are exploited (up to 1.6 miles = 3 km. length) although with lower speeds (<80 km/hr). Recently the success of high-speed passenger trains (Japan Bullit-train, France TGV, German ICE) resulted in the development of fast cargo trains (France TGV-frêt) running up to 300 km./hr. However, in most cases in Europe cargo trains may reach average travel speeds of 25-40 km./hr (due to border-crossing, change of locomotives etc.) carrying up to 3000 tons/trains. In the mining industry private companies exploit special designed equipment, sometimes carrying more than 10.000 tons per train with speeds of 50-75 km./hr. Road transportation After the second world-war road transportation developed into the dominant mode of transportation for inland and domestic cargo movements. In many countries more than 70% of all cargo movements are realised with road trucks, carrying pay-loads up to about 30 metric tons with average speeds of ± 75 km/hr. on the trunk routes. The offered low cost per tonkm, the flexibility and reliability, the favourable ratio: pay load/gross vehicle mass and the dedications of truckers to their customers have resulted in a very strong position for trucking. However infrastructural limitations (congestion), environmental demands, governmental directives and regulations are now putting restrictions to further growth. Cost developments (driver, fuel) and traffic congestion (the average delivery speed in big cities has decreased to 10-15 km/hr) made people aware of the limitations in road transportation. Air cargo transportation This is the latest mode of transportation, mainly for time-critical and/or high-value cargo. Full freighters (airplanes for air cargo only) can carry up to 130 tons of payload with speeds of about 900 km/hr. In tons per year air cargo transportation is still 5 insignificant but value-wise, air-cargo contributes largely to high-value-commodity trades and supports the developments in e-commerce (see also par. 5). Combined passengers and cargo transportation Until the second world war the combined movement of cargo and passengers was widely spread. Sea going vessels with capacity for cargo and passengers; in the early days towboats and mail-coaches and later trains for passengers and general cargo mainly (supplies) were widely used. Only in recent decades freight transportation is almost completely separated from passengers transportation, and in Europe passenger trains have priority over cargo trains. Congestion in large cities, a growing awareness of environmental requirements, cost developments and limitations in infrastructure will probably support a revival of combined passenger and cargo transportation, although many problems need to be solved. Pipeline The largest pipeline systems are used for the transportation of water (only in the Netherlands already 1250 mill. tons of water per year). Second best is the transportation of gasses, oil products and chemicals (approx. 200 mill. ton per year). The applications for pipeline transportation are numerous however public domain applications are limited due to the limited infrastructure. In (private) manufacturing plants pipeline transportation is a widely spread, reliable and cost-effective means of transportation for liquids, gasses and powders. Integration in transport chains In the past, transportation links were almost autonomous. Products were accepted in the shape they were offered. Cargo handling equipment was designed to handle loads larger than man-loads and to speed up handling processes. In the last decades there came more concern about the required functionality in transportation and handling processes. The first bi-modal (cart-train; truck-train; vessel-train) transportation links showed a certain co-ordination between the means of transportation, packing of cargo and handling techniques (and related equipment); on top of that information became increasingly important to control the growing flows of cargo. 6 Economies and a growing dependability on the supply of goods encouraged the development of proper relationships/connections between transportation and foregoing and/or subsequent processing from raw materials into finished products. Today, transportation is an integrated activity in the overall production chain from manufacturers to consumers. Every product chain (showing the creation of products from winning up to consumption and finally removal/re-use) has many stages of transportation and handling (see Figure 5). So today place and time of transport is fully integrated in the industrial product chain. The most developed integration has been realised in the internal transportation processes within the manufacturing of products. Nowadays a large variety of handling winning transportation techniques, automated transportation and storage information control systems, support an production 1 efficient production of goods, where in winning initiated trigger. Some decades ago Physical Distribution covered all activities from material sources to the production line and from the production line to the consumer including the transportation storage storage production 2a production 1 production 2b transportation transportation winning storage storage transportation production 2a production 3 storage production 2b storage production 1 transportation transportation storage products only starts after a consumer transportation transportation many cases the manufacturing of consumption storage movement of raw material, freight transportation, warehousing, material handling protective packaging, inventory control, plant and warehouse site selection, order processing, market production 3 production 2a storage production 2b transportation transportation consumption storage forecasting and consumer service. This physical distribution developed into production 3 =port storage transportation today’s Supply Chain Management, consumption covering the management and handling of all material and information required for Figure 5 Various product chains the production and delivery of products. 7 Definition Transport Technology “Transport Technology covers the technology required for all activities in the field of transportation, storage, handling and information/communication for a controlled efficient movement of goods from origin to destination”. The sub-faculty of Mechanical Engineering focusses on the functional requirements to transportation means (concepts, handling provisions) innovative transportation concepts and all technology for storage and handling of goods, in particular on the interchange area’s such as manufacturing plant inlet/outlets, inland consolidation/distribution centres, intermodal terminals, terminals for seaports and airports. 2. Developments in transport Transport technology is in a continuous symbiosis with the society. On the one hand transportation techniques and handling methods support new approaches in the society (globalisation, automation, improved planning) and on the other hand developments in society (e-commerce, cost control, better working conditions, awareness of scarcity) encourage new concepts for transportation and handling. Some major developments and their impact on transport technology are mentioned below. Growth in transportation of goods The growing population (6 bill. people in 2000 and maybe 9 bill. people in 2050) and the improvements in income per man (growing wealth) result in a continuing increase of the transportation goods. The awareness of scarcity of raw materials and the set-up of processing plants for half-products close to the winning area’s will cause a likely growth in the transportation of raw materials of 2-3% annually for the coming 10-20 years. In contrast to this, is the transportation of half-products and consumer goods. The openings of new trade lanes to developing countries, the stimulations to new needs in consumer goods (fresh fruit during the whole year, exotic gifts from all over the world etc.) and the effects of globalisation show an ongoing growth in the transportation of consumer goods, not only domestic, but international and intercontinental as well. 8 The growth figures for the transportation of consumer goods are estimated as 5-8% annually, but in some area’s (think of China, India, South-America) the emerging economic developments could cause these growth figures to be even higher. Figure 6 shows the growth development for international containerised transportation as a part of overall general cargo transportation. It clearly indicates the yearly growth and the continuing transition from general cargo into containerised cargo. This has a large impact on transportation networks (shipping, rail, and road) and the required facilities in ports and inland terminals and on the facilities at manufacturing plants and distribution centres. 5,00 containerised Tons in Billions 4,00 non containerised 3,00 2,00 1,00 0,00 1996 1998 2000 2002 2004 2006 2008 2010 2012 2014 Figure 6 Development in world-wide general cargo transportation Globalisation The liberalisation of world-wide trade, the fierce competition both national and international and an overall driver to get more for less money, has resulted in a spread of production activities all over the world. Leading companies decrease their numbers of manufacturing plants, benefitting from the economies of scale and low labour cost in certain parts of the world. Traditionally car manufacturers used to produce almost all their components in their own factories; nowadays many carmakers purchase more than 50% of their components from abroad. This is only one example and there are many many more. Consumer electronics, fashion, furniture, machinery etc. are produced in low labour cost area’s (in parts or totally) and from there shipped to assembling plants and/or distribution centres close to the consumer markets. 9 The whole process of globalisation has been enabled through the availability of frequent, low-cost and reliable world-wide transportation. This in reverse results in cargo flows which are a multiplier of the flows related to the end consumers goods. The production of aluminium, the distribution (via auctions) of flowers and the production of clothing learns that sometimes 3-5 times the final amount of tonnes is shipped thousands of miles all over the world (see Figure 7). The prices for raw materials are more and more determined by the overall transportation costs, this in contrast to consumer goods where the shipping in containers has resulted in low transportation cost per product, a real stimulant for further globalisation. Consequences for Transportation: 5 tons bauxite - 5 tons bauxite 100 km - (rail)transportation - 2 tons Al-oxide 5000 km - sea transportation 2 tons Al-oxide - 0.5 ton carbon 5000 km - sea transportation 0.5 tons carbon anodes - 1.7 tons coal 14.000 km - sea transportation electrolysis 13.800 kwh 1.7 tons coal - 1 ton Aluminium 2000 km - road/rail/coastal transp. Total: 38.800 tonkm 1 ton Al. rotary casting extrusion Figure 7 Transportation demands for 1 ton aluminium products Logistic networks Globalisation and the still increasing consumer demands have resulted in complex systems for the distribution and delivery of goods. At present almost every manufacturer maintains a variety of channels (chains) to guarantee that products arrive in time at the consumer and to guarantee a proper supply of raw materials, halfproducts, tools etc. 10 The society is used for many years, to supply chains where-in the supplier Supplier (manufacturer) pushes products into Supplier Manufacturer Retailer Consumer the direction of the consumer (using business development, marketing, Supplier A Supply Chain (push) advertising etc. (see Figure 8a). Consumer Recently (and even further emphasised by E-commerce) the suppliers have Supplier Manufacturer Retailer Consumer noticed that costs can be reduced and B product inventories can be lowered if Demand Chain (pull) production processes are triggered by Consumer Supplier the consumer himself. This is a demand chain where the consumer is Manufacturer purchasing, manufacturing, distribution and final delivery (see Retailer Supplier pulling the entire process of material Consumer Manufacturer Supplier Consumer C Retailer Demand + Supply Chain Consumer Figure 8 Various supply chains Figure 8b). In practice both types for the management of movements of goods/cargo are mixed into logistics networks, supporting a demand and supply chain management (Figure 8c). In logistic networks partners aim for the lowest overall processing, transportation and distribution cost for the entire chain of activities and partners allow each other information about delivery patterns, fluctuations, minimum response times etc. This regularly results in higher costs for transportation and handling (smaller shipments, more frequent, demand driven deliveries), but overall lower cost (fewer inventories cost, storage space, leftovers etc.). The negative effects on transportation and handling (lower utilisation, less potential for scale economies) can be avoided when logistic providers combine transportation, collection and distribution for a multitude of product chains. This phenomenon and the general tendency to outsource activities not belonging to the core-business has encouraged companies like UPS, TPG, Fedex to provide logistic services and to 11 operate as logistic integrators. Logistic services (from only transportation towards stock-keeping, assembling, distribution, pick-and-place etc.) are defined in servicelevel-agreements and the logistic product is measured through performance indicators (amount of deliveries outside the agreed delivery time, damages during transportation etc.). The worldwide control of such complex logistic networks requires a major effort in information control systems and a high-quality of IT-infrastructure. The success of logistic providers is often determined by their commitments to state-of-the-art IT-systems, planning and control tools. Logistic networks maintained by such logistic integrators are shown (in Figure 9) and the combination of many product demand and supply chains allows such integrators to apply scale economies in the respective collection, transportation and distribution networks realising the overall door-to-door transport of goods. Collection network Transportation network Distribution network 80% handling 20% transport 20% handling 80% transport 80% handling 20% transport Shippers Topics: Terminal Terminal Consignees • origin/destination • cycle time/frequency • critical mass/volume per destination • standardisation/information • VAL (value added logistics) Figure 9 Logistic network [source AT-Kearney] 12 Mechanisation The loading and discharging of goods was centuries long a process performed by men, carrying loads up to 100 kg (in sacks, bundled, etc.). Only heavy loads (marble blocks, wooden trunks) required innovative tools, finally resulting in revolving or fixed cranes in the middle ages (see Figure 10). Those cranes were driven by man-kind or animals (treadmill, hand-winches). The invention of steam engines and the following industrial revolution induced all kinds of mechanised tools. They allowed a faster handling of goods and caused a relief for the extraordinary “struggle” related with the handling of goods at the production or consumption places and/or the interchange area’s (e.g. from chariot into a tow-boat or Figure 10 Handling equipment in the MiddleAges sailing boat). Nowadays most of the handling activities in transportation and almost all handling in manufacturing plants is performed with the help of mechanical devices. Rolling equipment, belt and roller conveyers, pneumatic systems, power and free systems are only a few to be mentioned here. Mechanisation provides a faster and more reliable handling and also results in much better working conditions for labour. Obviously it requires a structuring in handling and transportation processes as demanded by the handling/transportation functions in the overall production and distribution chain. In many cases packaging of goods, standardised loads and shipment volumes are determined by the available (or designable) handling and transportation means. New directives and regulations for labour (but as well our own human engineering conscience) in Western Europe forbid a man-made continuous handling of loads 13 heavier than 15 kgs. The handling of loads heavier than 25 kgs is basically not allowed (e.g. cements sacks have been changed from 50 kgs content into max. 25 kgs content). Mechanisation is a key-element in transport technology and that’s the reason why transport technology is widely integrated in the manufacturing and distribution industry. Automation After the mechanisation of production and transportation, the first developments of automated (= unmanned) processing were introduced in production plants (textiles, food) and for assembling lines (cars, machinery). Low cost mass production started about 100 years ago and the production industry showed the first integration’s of automated production and automated handling such as the positioning of components and the internal transportation to the next processing machine (overhead conveyors, power-and-free ground transportation). More than 40 years ago large companies in the automotive, electronics, paper and steel industry started to increase their production efficiency, reliability and quality and started to decrease their personnel expenses with the help of automation in production and logistics. They built the first automated storage system (e.g. high-bay warehouses), installed the first automated (wire)-guided vehicle systems and started to handle material with computer controlled overhead cranes and telpher lines (steel coils, steel slabs, paper rolls, assembly components etc.). A precondition for the innovations in automated processing and transportation was the simultaneous change of methods and logistics in the production. As a result, computer aided processes of all kinds have been implemented and support automation. Such automation tools are: operations planning, material dispositioning, order picking, warehouse control, wireless communications (see Figure 11) etc. Figure 11 Equipment for wireless data communication 14 A dedicated software industry developed, providing the industry with software packages for the control of the entire manufacturing plant, including the procurement of materials and the distribution of finished products. (e.g. softwarehouses like SAP, Baan, Oracle, JD Edwards). Automation in transportation and handling has supported the development of computer automated systems which are fully integrated in product supply chains. For example some container terminals have completely automated transportation and storage of containers allowing for fast responses on last minute changes, better flow control and long-term cost control. New logistic approaches such as Supplier Managed Inventories or Vendor Managed Inventory show complex supply chains, wherein suppliers (or vendors) are responsible for a minimum stock of products, including the planning and control of related transportation. Such complex operations are only feasible with the help of (partly) automated handling and transportation systems. Automation in handling and transportation is still at the beginning of its developments. Process redesign, new systems for handling and transport, new labour organisations and the integration of planning and control systems will encourage a further increase of automation in handling and transportation. Awareness of scarcity Fortunately there is a growing awareness of the limits in sources such as energy and raw materials, nature and available areas for infrastructure and economic developments. Increasingly, the society demands a better quality of life and so: technology developments must fulfil the requirements for less pollution (exhaust gasses, noise), less energy consumption, recycling of materials, preservation of nature etc. Transportation in particular puts heavy demands on natural resources, but at the same time supports the quality of life with respect to the supply of food, the distribution of goods and material prosperity. Transport Technology includes the awareness of scarcity, resulting in 2 major issues: 1. What possibilities do we have to avoid transportation. 2. When transportation is required, how can we minimise the negative influences on the quality of life. 15 Ad 1 The first issue focusses on raw material chains (e.g. enrichments of ores close to the mine), clustering of production activities at industrial sites to realise short transportation-links and even virtual networks to provide the shortest link between producer and consumer (avoiding collection and distribution). Ad 2 In this case transport technology focusses on the best suitable mode(s) of transportation, the achievement of high utilisation of transport vehicles (trucks, vessels, airplanes) the combination of logistics with reverse-logistics and the application of technologies with the lowest impact on the environment. The area utilisation for transportation can be improved when transportation utilise facilities and infrastructure 24-hours per day. Nowadays peak demands and avoidable organisational constraints restrict transportation to less than 50% of the available time (production plants, road transportation, rail networks). Future transportation concepts (think of city logistics) will emphasise on improved utilisation and multi-functional facilities. Many companies in the fields of manufacturing and transportation are aware of the limited resources at earth and have started a redesign of their processes, both internal and external. Transport technology must generate concepts to lower the impact on our scarce resources. E-business World-wide internet developments have enabled a new phenomenon in the consumption oriented society: E-business that allows commercial transactions with the help of electronic communications (bi-lateral EDI or Internet) and dedicated software packages. E-business is developing rapidly, especially in the area of business-to-business (B2B,) much slower is the take-off in the field of business-to consumer (B2C). Many companies realise electronic transactions for sales (or procurement) of services and products including “tracking and tracing” of such transactions and the belonging invoicing, payment. Obviously the sale of products must be followed with the physical delivery of the products. In this areas of e-logistics a new range of service providers has arrived at the scene. Parcel services, independent distribution centres, 16 electronic agents, E-markets (electronic auctions such as Flowernet) present themselves with the help of Internet and very advanced information systems to support the quotations, transactions and follow-up of their services. E-business is a tool for better (faster) service and lower cost (less sales-cost, fewer inventories), especially when various, in the supply chain connected, companies install forward and backward integration (e.g. supplier of components has direct access to the sales records of the end-products which allows him to control manufacturing and to optimise transportation of components to the storage of the final assembling plant). The development of e-logistics is still in the beginning; many transactions via e-commerce cannot be delivered according to the customer’s expectations. E-business has caused a decrease in the size of shipments and often results in the use of air transportation instead of rail, coastal or truck transportation. Especially in B2C transactions, the number of destinations has grown dramatically, resulting in more transportation (company-to-door instead of company-to-shop). Renowned companies of parcel services (VGL, UPS, Fedex) have entered the area of e-logistics, organising the entire logistic chain and that allows them to optimise transportation, combining many smaller shipments from many product supply chains into fewer larger shipments. E-business changed the control in supply chains from a push-approach into a pullapproach and this requires new organisations for supply chain management and the distribution of products. The fast responses and high reliability advertised in E-business has an impact on the design of handling and transportation systems. There is a challenge for more mechanisation and automation, supported through the existence of advanced information control systems, developed by the leading parties in E-business. Cost control For many years the transportation industry has not been a very profitable business, despite the annually increasing volumes and the growing importance for the fulfilment of material needs in the society. Economies of scale, specialisation in transportation and logistic services, supply chain management and the introduction of more advanced technologies has caused a reduction in the cost for handling and transportation. However, world-wide 17 competition, further potential for scale economies, mergers between logistic providers and an ongoing growth, both in cargo volumes and available capacity will continue to put pressure on cost reduction in the entire supply chain. This requires a total cost approach and a transparency for all cost elements per handling/transportation activity. With the help of Activity Based Costing (ABC) all costs can be analysed and the partners in the chain will be able to investigate what actions can result in cost savings for both of them (win-win-situations). Until now the transportation industry has been fully cost driven, often ignoring other relevant values such as environmental impact and labour conditions. This will probably change in the future: transportation will be charged for the use of public values (area for infrastructure) and on the long term liquid energy (gasoil, LPG) will become more expensive. Future designs of handling systems and transportation concepts should be increasingly focussed on long-term cost control, including the changing demands of the society. 3. Transformation, standardization and information For transportation the change of place (location) is characteristic and for many years products (goods) were transported in man-loads with limits in weight (up to 100 kgs) and size/shape (0,6 x 0,6 x 0,6 m). The goods can be sub-divided and classified as a MASS function of increasing size (see Figure 12). Figure 12 Classification of goods in sizes 18 The larger volumes and the availability of transportation and handling equipment helped in getting less dependent on the limitations of manually handled goods and nowadays many goods are transformed into transportable sizes/weights, in a standardized way and with sufficient information to control the transportation/handling activities. Transformation The transformation of goods and products is a required adaptation for storage, handling and transportation. Goods are transformed into units of a uniform external shape and size to serve the links in the total supply chain and to allow the application of mechanized and automated transport processes. The transformation of goods can have two directions. The first one is the transformation of goods into unit-loads with the help of standardized measurements of packages. The bundling of packages can be limited to pallets or rolcontainers but may extend also towards complete maritime containers or swap bodies. A second direction of transformation is towards bulk cargo (granulates, powders, liquids, gases), which can be moved very well by continuous conveyors. In this case the appearance of bulk goods can even be influenced by the selection of handling/storage/transportation equipment. Gases can be made liquid (easy to be stored) and pumped with the help of cryogenic installations; solids can be transformed into slurry (a pulverized condition mixed with a liquid like water or solvents). Figure 13 shows the two directions of transformation. In general the transformation of goods into bulk-handling requires a adaptation from the goods towards the equipment and the transformation into unit-load handling requires an adaptation of the handling equipment towards the unit loads. Finally a further transformation in bulk handling can be required when raw materials are used in production processes which demand a high homogeneity (of chemical and physical properties) of the used materials (such as iron ores, coal, limestone). Crushing, screening, weighing and sampling can be integrated in the transportation stage; homogenising (e.g. bed-blending, batch-blending) can be included in the storage stage. 19 KN Figure 13 Transformation of goods for unit-load or bulk handling In many cases the integration of transformation functions during transportation, storage and handling should be considered carefully in order to obtain the best results, cost-wise and service-wise. Standardisation Standardisation is probably the most important pre-requisite for a fast, safe and efficient handling and transportation of goods. Standardisation is important for the shape, size and weight of unit-loads, but also for all the interfaces where loads meet transportation vehicles (like vessels, railway wagons, road trucks etc.). Standardisation helps to design mechanised equipment and to introduce standard work procedures which are important to guarantee safe working conditions. Standardisation does not require that every piece of equipment or handling process is designed identically; to the contrary: standardisation can be limited to functional requirements in combination with a limited number of essential components and measurements. Examples are the king-pin of semi-trailers, measurements of pallets, freight documents, wheel diameters for equipment (e.g. cranewheels 500, 630, 710, 800 mm) corner castings of containers, coding of cargo and unit-loads, coding of dangerous goods, etc. 20 Costs for the handling of goods are substantial, both for the internal transportation during manufacturing and for the transportation from the producer to the consumer. Therefore standardisation was introduced for the packing of products, based on the packaging module 40 x 60 cm suited for bundling onto Euro-pallets (80 x 120 cm) or the industry-pallet (100 x 120 cm). A variety of cardboard boxes can be assembled into these standard measurements (see Figure 14). Industry pallet 100 x 120 cm (5 modules) Euro pallet 80 x 120 cm (4 modules) Packaging module 40 x 60 cm 60 x 40 cm 60 x 20 cm 60 x 10 cm 40 x 30 cm 40 x 20 cm 40 x 10 cm Series of measurements: 1260 : : : : : : : : : : : : : 2 3 4 5 6 7 9 10 12 14 15 18 20 = = = = = = = = = = = = = 630 420 315 252 210 180 140 126 105 90 84 70 63 1200 : : : : : : : : : : : 2 3 4 5 6 8 10 12 15 16 20 = = = = = = = = = = = 600 400 300 240 200 150 120 100 80 75 60 30 x 20 cm 30 x 10 cm 20 x 15 cm 20 x 10 cm 15 x 10 cm Figure 14 Standaardisation into modules The time and cost consuming handling of goods (in boxes, sacks, or palletised) when changing modalities (road √rail, road√vessel etc) made Malcolm Mclean (a trucker in the USA) decide to move a completely loaded semi-trailer onto a specially designed vessel. That was the beginning of containerisation, with standardised boxes: 20’container, 40’ container. Unfortunately the measurements of maritime containers were based on the US-regulations for road transportation (max 8’ wide; 35’ length; later 40’, 45’, 48’ and 53’), which were not comparable with European metric measurements. However, the introduction was so successful that the whole industry has accepted the shortcomings from the early (non-metric) dimensions. For European domestic transportation and for coastal shipping a pallet-wide (2,5 m. wide) container has been introduced. 21 20 ft ISO Container 40 ft ISO Container 20 ft ISO Refrigerated Container 40 ft ISO Tankcontainer Figure 15 Various types of standardised maritime containers The tremendous success of the world-wide container transport concept can be attributed to a large number of factors: • the rigid standardisation with simple vehicles and handling systems; • the introduction of specially designed, highspeed (up to 27 knots) vessels, with standardised holds (cell-guide systems) and simple lashing for containers on deck; • Mclean released many patents to competitors and standardisation committees (no protection of his own inventions); • the only regulations regarded the 8 defined corner points in space and the shape and dimensions of these corner castings; • a variety of container types, both for general cargo and special commodities (refrigerated cargo, liquids, overheight cargo etc.) all based on the same 8 defined corners points (Figure 15); • basically the maritime container is lifted by means of the 4 top corner fittings (castings) and fastened through the 4 bottom corner fittings; • substantial savings could be achieved in all parts of the transportation chain (due to increased scales, competition, efficient methods); • the increased transportation speeds, first on the sea-leg later on land as well; 22 • the container offers a good protection (weather, pilferage) and makes a superstructure for semi-trailers, railway wagons and barges superfluous; • each container was given a unique identification number (e.g. SLDU 1234567) and size-type code (e.g. 4010), which facilitated “tracking-and-tracing” and planning for all parties in the chain; • the container could be used for temporary storage of goods (warehouse functions); • during the Vietnam war the USA government spent much money on the developments of container handling, vessels, semi-trailers and railwagons; • meanwhile the cost component of the container is less than 5% of the total transport costs. The application of standardisation in unit-loads, handling equipment, vehicles, operating methods, coding etc. is a must for mechanisation and automation. Standardisation supports reliability, maintainability and cost reductions. Many measurements of standardised components for equipment have been based on “series of preferred numbers” such as series R10: 1-1,25 – 1,6 – 2,0 – 2,5 – 3,15 – 4,0 – 5,0 – 6,3 – 8,0 – 10,0. Information The control of the transport of goods requires a flow of information, which runs parallel, or preferably in advance of the physical movement of goods. Information must be available at the right place, at the right time and in the required format. Information for transportation can be structured in two categories: 1. Information related to products and equipment. 2. Information related to the transportation process. Ad 1. This information characterises the product (article-number, manufacturing data, production plant, specific weight, colour etc.) or the transportation equipment (trailer number, railcarnumber, unit identification number, max pay-load, date of latest technical inspection etc.). 23 Ad 2. This information is necessary for an efficient transportation process. Such information characteristics are: origin/destination code; planned voyage number, latest arrival date, shipper/consignee, storage directives. Again the standardisation of information is very important as well as the structuring of messages required for an efficient transportation (EDIFACT). Many technologies are available for the connection of information to products such as bar-codes, structured characters (OCR = Optical Character Reading), transponders (passive or active), magnetic strips etc. Before selecting a world-wide standard it must be proved that the information carrier can be read with a 100% reliability. This is necessary to apply automatic readers for the registration of changes in status during the transportation process (passing a gate (Figure 16), change in modality, customs inspection etc.). Figure 16 Automated checking and tracing in container terminal gate Information processing has many similarities with transportation and transformation (think of data-collection, data processing, data storage, = database) and should be managed carefully. Today it is no problem to distribute a multitude of data to all actors in the transportation chain however, it is recommended to process only the minimal amount of data required for the respective actors. 24 The importance of information systems for transportation is paramount. Large manufacturing companies (General Electric, IKEA) maintain their own information systems for the management of the distribution of their products, Major logistic integrators and global transportation companies fully depend on the quality of their information systems. Increasingly the success of a transportation company (shipping lines like Maersk, P&O, APL, Evergreen; parcel services like Fedex, UPS; container terminal operators like Hutchison, P&O Ports) is determined by advanced information systems and belonging planning and control tools. 4. Systems approach Transportation systems often have a complicated structure, connecting various components and with many influences from outside actors and numerous relations between components within the transportation system. For the analysis of existing transportation/handling systems and for the conceptual design of new installations a systems approach is a helpful tool. Systems theory can contribute considerably but requires a proper definition of a system, its required functionality, the related influences from outside and the properties (characteristics) of all components assembled within the system. In general a system is an assembly of components (or elements, objects, entities) separated from the total reality wherein the components of the system are connected by means of relationships and possible relationships with components not belonging to the defined assembly of system components. Figure 17 presents a schematic of a system with the following relevant notions: • elements (components, entities, objects), being the smallest parts to be considered (handling equipment, vessel, vehicle, hoisting winch). Elements have certain characteristics indicated as attributes, which can by physical, geometric, aesthetic (vessel ™ speed, carrying capacity, colour, air pollution etc.); • relationships, which describe a certain coherence between the elements. The influences (or interactions) can be described quantitatively or qualitatively. Think of a vehicle on the road, a gearbox connected to an electric motor; • structure being the assembly of all relationships. 25 For the analysis of the overall systems behaviour, elements can be considered as black boxes when the internal components and their relationships of such an element are not (yet) relevant. Cranes, storage systems, vehicles can be considered as black boxes described through their characteristics (relationships) with other elements in a system. Another approach for the analysis of systems is a more detailed focussing on either the elements (analysis of sub systems) or the relationships (the analysis of an aspect system or partial system (see Figure 18). A sub system (vessel, storage system etc.) is a subassembly of some elements in a system with all relationships still under consideration. SUBSYSTEM aspectsystem (part of the relations between all components ) relations surrounding element/component Figure 17 Schematic of a system 1 ASPECTSYSTEM aspects (relations) subsystem (some components + relations) elements system boundary (to be selected) Figure 18 Various approaches in focussing systems analysis An aspect system (or partial system) is a subassembly of the relationships between all demands of the considered system (information control in a transportation system, the social impact of a transportation system). The modelling of systems for transportation/handling of goods normally is limited to a number of subsystems and the analysis of some relationships (capacity; cost of sea transportation; service and infrastructural demand of a rail connection; environmental impact of a storage system). The proper description of quantitative and quantitative relationships within a systems model will contribute to analyse the characteristics of the overall system, however, only for the relationships that are described. 26 When it comes to an assessment of the total systems service, or the systems costs, a variety of aspects must be considered such as: • analysis of service performance between the connecting transportation modes and their related handling systems; • the impact of break-downs in the overall systems output; • required service levels during the day (week, year); • assessment of required services and related costs; • estimate of total investments, total operating costs and impact on public facilities. In many cases, systems boundaries should not be too limited as it may block the development of improvements (see Figure 19). The increased number of partnerships in transportation allows a broadening of systems boundaries and that is illustrated by transportation systems which are fully integrated in the total production chain (e.g. the transhipment of half-products in climate controlled bulk containers). The systems approach can result in other techniques for transportation, handling and storage, with an overall systems improvement (faster, less cost, less damage, more flexibility etc.) sugar factory confectionery fact. trolley turbine generator condensor mobile crane selected system boundary Figure 19 Enlargement of system boundaries creates new solutions Unfortunately the optimisation of overall transport systems (towards speed, costs, environmental impact) is often blocked as a result of the many parties involved, who are not willing to share profits and costs for an overall systems improvement. Strong parties in a logistic chain try to optimise their own operation (process) at the cost of others (forward or backward) in the overall transport chain. Especially when it comes to the utilisation of public sources there is a lot to be improved when applying a systems approach. 27 It is recommended to assign multi-disciplinary teams for the application of a systems approach in transport systems. The combination of operations experience, civil engineering, logistics, equipment engineering, economics, environmental awareness etc. is essential in the development of transportation/handling systems best suited for the overall transportation chain. 5. Related Topics As indicated earlier, transportation and handling is an indispensable element of our society, influencing the quality of life both positively (mobility, supplies, employment, distribution of scarce goods) and negatively (air and noise pollution, energy consumption, land-use). The impact of transportation on our society can be derived from the contribution to the economy, safety aspects, environmental influences and the numerous directives related to transportation and the design of handling systems and means of transportation. Some illustrations are given below. Contribution to the economy Some facts and figures for Europe (the EU) are (statistics 1998): • the added value created by the transport services sector and own account transport is 375 billion Euro per year; • 6 million people are employed in the transport services sector (approx. 320.000 people in the Netherlands only); 2 million people in the transport equipment industry and another 6 million in transport related industries. This represents almost 10% of all persons employed in the EU; • total transport demand in the EU was 2870 billion tonkilometers, or 7700 tonkilometers per person per year or almost 20 tonkm per person per day. The share for the various modes for the EU is: road 44%, sea 41%, rail 8%, inland waterways 4%, pipelines 3%. • The value density of goods transported varies tremendously with the mode of transportation. Obviously low value commodities (coal, ore, scrap, and waste paper) are preferably transported with low-cost/high-volume modes of transportation like barging or rail. The value density per mode of transportation is: 28 air 15269 Euro/ton road 1661 “ rail 971 “ sea 872 “ pipeline 112 “ 83 “ inland barging These average figures (Intra European Transport in the EU) illustrate what values of cargo are moved with the various means of transportation (e.g. 30.000 tons in a medium size container vessel; 125 tons in a Boeing 747; 3000 tons in a train; 10.000 tons in a 4-barge convoy and 30 tons in a road truck). One shipment of cargo may represent some tons of thousands Euro up to some tons of millions Euro. The capital cost only is already a reason to transport as fast and efficient as possible. That’s why it is so important for the handling in terminals, airports etc. to reduce cost and improve transportation speeds. The importance of mainports is shown in the Netherlands where more than 8% of the GDP (Gross Domestic Product) is contributed by the Dutch Seaports and related activities. (equals ± 23,5 bill Euro in 1999). It is obvious that transportation can be considered as the arteries of the society. Safety Unfortunately transportation causes accidents, mainly caused by road transportation. In 1997 43.404 persons were killed and 1.7 million people were injured in road accidents in the EU and only 139 persons were killed due to rail accidents (1997). In the Netherlands 1163 persons were killed and about 54.000 were injured in road accidents (1997). Road traffic is by far the dominant cause of accidents in transportation (in ± 15% of all accidents there are trucks involved); when it comes to other area’s of transportation and handling (ports, manufacturing) safety is rather high due to the continuous attention both from designers, operators and governments. Many types of equipment must be designed according to detailed design directives, presented in design standards and governmental directives. On top of that every manufacturer of equipment must present a risk analysis with the commissioning (purchase) of equipment. Nevertheless safety is a major issue for transportation and handling of 29 goods. The impact of fast moving heavy loads should never be underestimated; it is the duty of every engineer to asses safety in every professional activity. Environmental Impact Air pollution and energy consumption are the environmental topics with the most attention from the society. Noise pollution and the preservation of nature come next. The explosive growth in road transportation caused a tremendous impact on the environment however, the last ten years showed noticeable reductions both in air pollution, noise pollution and energy consumption as a result of road transportation. Some figures (Eurostat 1996): Mio tons Total Emissions Transport Industry Road transport NOx 11,93 6,26 (52%) 4,79 (40%) CO 40,96 25,45 (62%) 23,12 (56%) SO2 9,39 0,56 (6%) 0,37 (4%) Pollutant The pollution with NOx by road transportation is almost equally spread over passenger and freight transport. When it comes to SO2 75% is caused by shipping (barges and sea going vessels) in which sea transportation contributes almost two thirds. The strict directives for road transportation have resulted in remarkable reductions of air pollution. Emission standard EURO III (1-1-2000) will be succeeded with EURO IV (1-10-2005) and EURO V (1-10-2008). For road trucks EURO V will bring further reductions in CO (-27%), NOx (-60%) and solid particles (-80%). The EURO V requirements for road trucks will result in a lower NOx pollution for road trucks in comparison with inland barging and rail transportation. When it comes to CO2 emission per tonkm barging and rail still outperform trucking, however for rail transportation these figures are based on a majority of energy supply from non-fossil fuels (nuclear in France, Spain, UK, Germany and hydro in Sweden, Switzerland and Austria). 30 In 1997 transport required 31% of the total energy consumption; more than 80% caused by road transportation (passenger + freight). See also Figure 20 for the development of CO2 emissions for the various energy consumers Noise pollution is getting more attention. Over the last 25 years a 50% reduction in loudness has been obtained from motor vehicles (passenger cars 1972 82 dB(A) 1996 74dB(A); trucks 1972 91 dB(A) 1996 80 dB(A)). Figure 20 CO2 emissions for the various energy consumers In the Netherlands there is a lot of attention for the noise load onto housing. the objective is that the noise load should be less then 65 dB(A). The society is limiting the area requirements for transportation infrastructure. The emphasis in the future will be the avoidance of transportation (clustering of activities in industrial parks) a modal shift (more barging and rail transportation) and a better utilisation of existing infrastructure (think of ITS = Intelligent Transport Systems, platooning see Figure 21). Pricing of infrastructure (road pricing for cars/trucks and pricing of the railway tracks to rail operators) will be increasingly used to reduce the growth in infrastructure. This trend will effect transportation concepts for the distribution of consumer goods. Figure 21 Increased utilisation of infrastructure with platooning of vehicles 31 6. Challenges for Transport Technology The tremendous developments in production, consumption and trade have caused a large demand for transportation. In many places of the world existing transportation systems are reaching their limits (limited infrastructure, handling complexity, environmental restrictions etc.). Especially in densely populated area’s, new transportation concepts will be required to handle the continuing growth in the transportation of goods. The department of Transport Technology and Logistics is focussed on such new concepts, some of them are presented below. Multi-trailer-systems Multiple trailer vehicles have been known to the industry for almost a century; however, the applications were limited to military services and large manufacturing plants. Since the 1950’s there has been a boom in their use at airports, but with limited loads up to 5 tons per trailer. After the maturing period in containerisation (1955-1975) the Dutch Container Terminal Operator ECT (Europe Combined Terminals) studied new designs for internal transportation. In co-operation with the Delft University of Technology a new (patented) Multi-Trailer-System (MTS) was developed and installed (see Figure 22). Figure 22 Multi-Trailer-System (MTS) at ECT Rotterdam 32 The system has the following advantages: • an increased transportation performance (10-14 TEU per train with speeds up to 30 km/h); • low transportation cost (only one driver for 10-14 TEU and the possibility of coupling/uncoupling the tractor to the trailer-set); • designed for the use on existing infrastructure; • precise tracking due to the unique all-wheel steering with special transfer functions between pull-bar/front-axle and front-axle/rear-axle. After 25 years of successful operations at terminals the application of (track-keeping) multi-trailer-systems can be extended to other applications such as cargo transportation at the main corridors (see Figure 23) and cargo distribution in city centre’s. A research programme at the Delft University of Technology demonstrated that a special speed-dependent addition to the steering mechanism of the trailer will allow MTS-speeds up to 70 km/hr with sufficient stability. Modelling the MTS by using multi-body techniques (the ADAMS package) showed that a modified steering system allows both a precise tracking with a small swept path at low speeds and good stability (lane changes) at high speeds. Figure 23 Utilization of multi-trailer-systems at main corridors 33 In large cities there is a trend to reduce cargo truck dimensions (total GVW, maximum width + length) and there an MTS comprising of smaller trailers (e.g. 3 tons per trailer, 2,2 meter width) could be used to distribute standardised city-boxes between distribution centres and consumer outlets. Underground Freight Transportation The problem of transportation in urban area’s can be avoided through the application of automated underground freight transportation. In Japan, Switzerland and the Netherlands feasibility studies have proved that such new transportation systems will be required and affordable in the future. In the Netherlands a pilot project has been defined for the underground transportation of goods in the Schiphol area (approx. 25 km track length) between Schiphol airport, the flower auction of Aalsmeer and a new rail terminal near Hoofddorp, which will connect Schiphol with the rest of Europe by means of an international network of high-speed freight trains. The design phase for this new concept is running and some vital elements like the automated guided vehicles and handling interfaces are in the prototype stage. Airmodule Flower carts Aircraft pallet Figure 24 Various cargo types for underground freight transportation at Schiphol The various types of cargo to be transported (see Figure 24) must be accommodated by the automated vehicles. At present 3 different prototypes (scale 1:1) are tested to analyse driveline characteristics, vehicle dynamics, manoeuvring at high speeds, positioning accuracy and robustness (MTBF). The interaction between the different components and the overall control systems are investigated as well (see Figure 25). 34 Figure 25 Full scale prototype testing (vehicles + handling + control) Regional and Urban Logistics Centres The distribution of consumer goods in urban areas is increasingly hampered by all kinds of regulations, aimed to improve the quality of life in cities. In addition there is a growing awareness about the needs for reverse logistics (collection, separation and treatment of waste material) and the possibilities to substitute road transportation through rail transportation and barging. These trends will influence the manifestation of city logistics. Special city delivery trucks with electric or hybrid drive lines are being developed and new city distribution concepts and belonging logistics will be required to fulfil the future demands from consumers: faster delivery of smaller parcels; a large variety of consumer goods in the shopping areas and a reduced environmental load at the same time. The development of multifunctional logistic parks in the cities will support these increased requirements to city logistics. Figure 26 shows a concept for such a logistic park offering a variety of advantages such as the connection to three transportation modes; a clustering of activities which avoids transportation; an interface between low-cost large-scale transportation networks (rail, barging) and a high-frequency city delivery network with electric vehicles or even underground automated freight transportation. 35 Figure 26 Multifunctional logistic park Applied research at the Delft University of Technology and projects with distribution companies and key players of the retail industry will result in improved city logistics. Even combined transportation of passengers and goods (see Figure 27) is studied to investigate which types of facilities may be required in the future. Figure 27 Intercity – FreightCombi, combined transportation of passengers and goods 36 The above mentioned new concepts are just a few of many developments within the field of Transport Technology. Sustainable technology and more intelligent transportation systems can be realised tomorrow. A multi-disciplinary approach and the application of various techniques from many technical disciplines characterise the activities of transport technology. The variety of systems and equipment is still growing as a result of the increased integration of transport in modern society. Delft, 3 October 2001 Prof.ir. J.C. Rijsenbrij 37 ...
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