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1、Chapter 7PipelinesBrief HistoryPlayed an important role in the transportation industry in the post-World War II era.Early in the twentieth century,the oil companies operated the pipelines as integrated subsidiaries and often used them to control the oil industry by not providing needed transportatio
2、n service to new producers.Significance of PipelinesPipelines are limited in the markets they serve and very limited in the commodities they can haul.The only mode with no backhaul,;i.e.,they are unidirectional with products that only move in one direction through the line.Significance of PipelinesM
3、ore than 57.5 percent of the total intercity ton-miles shipped in the US in 1995.They are virtually unknown to the general public but represent a key component in our transportation system.P.195.Pipeline diameters have increased in recent years,and the larger diameters have increased capacity signif
4、icantly because of the increased volume that can move through the pipeline.Types of Carriers&OwnershipAlthough some private carriers exist today,the for-hire carriers dominate the industry as so called common carriers.Oil companies have been the principal owners of pipelines.Number of CarriersLike t
5、he railroad industry,the pipeline has a small number of very large carriers that dominate the industry.20 major integrated oil companies control control about two-thirds of the crude oil pipeline mileage.Number of CarriersReasons for the limited number of pipeline companies.Start-up costs are high.L
6、ike railroads and public utilities,the economies of scale are such that duplication or parallel competing lines would be uneconomicA 12-inch pipeline operating at capacity can transport three times as much oil as an eight-inch pipeline.Oil CarriersP.197.Intercity ton-miles increased to 628 billion i
7、n 1997.The reported operating revenue decreased from 1985 to 1992 by almost 4 percent.However,oil pipelines play a major role in our transportation network,because they transport more than 20 percent of the total intercity ton-miles.Natural Gas CarriersThe movement data for natural gas are presented
8、 in cubic feet,rather than ton-miles.P.197.Shows that operating revenues also decreased in 1985 with the decline of the volume moved.Commodities HauledVery specialized carrier in that they transport a very limited variety of products.Four main commodities hauled areOil and oil productsNatural gasCoa
9、l chemicalsOil and Oil Products1994,crude oil and oil products accounted for approximately 57 percent of total pipeline use.(Table 7.6)The split by modes between pipeline and water carrier has changed for several reasons.Alaskan=Panama=Atlantic CoastWest Coast To MidwestLength of haul is medium comp
10、ared to other modes.Crude oil movements average about 800 miles per shipment,and product lines average about 400 miles per movement.Buy size is large.Natural GasAccount for the second largest number of miles of intercity pipelines 266,900 miles.(Table 7.7,Page 199)The natural gas companies produce a
11、bout 10 percent of the gas they transport.Independent companies produce the remaining 90 percent.CoalCoal pipelines are frequently called slurry lines because the coal is moved in a pulverized form in water(one-to-one ratio by weight)Remove the water once it arrived and the coal is ready to use.Prim
12、arily used for transporting coal to utility companies for generating electricity.Use enormous quantities of waterSome states are a scarcity of waterThe water is not reusable(no backhaul)ChemicalsA limited number of different types of chemicals are carried by pipelines.Three major chemicals areAnhydr
13、ous(無水的)ammonia for fertilizerPropylene(丙烯)used for manufacturing detergentsEthylene(乙烯)used for making antifreeze(防凍劑)Relative AdvantagesLow ratesAverage revenues for pipeline companies are below one-half of a cent per ton-mileHave a very good loss and damage record Types of products transportedUnd
14、erground and completely encased movementProvide a warehousing function because their service is slow(an average of three to five miles per hour)Relative DisadvantagesAlthough its slow speed can be considered an advantage due to its use as a free form of warehousing,in some instances the pipelines sl
15、ow speed can be considered a disadvantage.Like sometimes need to hold higher levels of inventory to compensate for possible shortages because the pipeline will not be able to deliver an extra amount of the product in a short period of time.Relative DisadvantagesOffer a relatively fixed route of serv
16、ice that cannot be easily extended to complete door-to-door service-limited accessibility.May not be a critical problem because the source of the pipelines and the location of the refineries are known and are fixed for a long period of time.Frequently,pipelines depend on railroads and motor carriers
17、 to complete delivery,which adds to user costs.Relative DisadvantagesLimited to a rather select number of products:crude oil,oil products,natural gas,coal,and a limited number of chemicals.There is interest in using pipelines for other products but the technology has not yet been fully developed.Cap
18、sule(膠囊)&pneumatic(有氣腔的)pipelinesFrequency of ServiceLarge tenders(shipment size requirements)and slow speed of pipelines reduces the frequencyOn the other hand,service is offered 24 hours a day,seven days a week.CompetitionIntramodal competition is limited by a number of factorsSmall number of comp
19、anies limited price competitionThe economies of scale and high fixed costs have led to joint ownership of large-diameter pipelines because the construction of smaller parallel lines is not very efficient.High capital costs preclude duplication of facilities to a large extentIntermodalCompete with ra
20、ilroads,water carriers,and motor carriers,however,the level of competition is limited.The most serious competition is water,or tanker,operations.Truck service complements rather then competes with the pipeline,because trucks perform a distribution function for pipelines(i.e.,delivery).IntermodalOnce
21、 a pipeline has been constructed between two points,it is difficult for other modes to compete.Costs are extremely lowDependability is quite highLimited risk of damage to the product being transportedOnly exception is probably coal slurry pipelines because of the need to move the pulverized coal in
22、water can make the costs comparable to rail movementsWater carriers come closest to matching pipeline costs and rates.EquipmentTotal pipeline investment is in excess of$21 billion,it would cost about$70 billion to replace the system at todays costs.共通管道Commodity MovementGathering lines bring oil fro
23、m fields to a gathering station,where the oil is stored in sufficient quantity to ship by trunk line to a refinery.After refined,the various products are stored at a tank farm before they are shipped via product line to another tank farm.A motor carrier most frequently makes the last segment of the
24、trip,to the distributor or ultimate customer.Commodity MovementTrunk lines are usually more than 30 inches in diameter and are the major component of the pipeline system.Stations that provide the power to push the commodities.For oil movements,pumps are located at the stations,which vary in distance
25、 from 20 to 100 miles,depending on the viscosity of the oil and the terrain.Commodity MovementPumping stations for large-diameter pipelines can provide 3,000-6,000 horse-power.Compressors are used for natural gas and pumps are used for the liquid items.Pipes are constructed of special high-quality a
26、lloy steel with a life expectancy of 50 years or more.Commodity MovementSafetyRequiring pipeline operators to identify facilities located in unusually sensitive areas and high density population areasMaintain maps and records detailing that informationProvide those maps to federal and state official
27、s upon requestPipeline is coated with protective paints and resins,and special techniques are used to control corrosion after the pipeline is in the ground.Commodity MovementComputers at the pumping stations continually monitor the flow and pressure of the oil system.Any change indicating a leak is
28、easily detected.Routine visual checks and searches by airplane are sometimes used to located leaks.15 grades of crude oil and a range of products including jet fuel,kerosene,and aviation fuel.Usually,products are scheduled one month in advance with kerosene moving first,then high-grade gasoline,then
29、 medium-grade gasoline,then various other products,then with home heating oil last.Fixed V.S.Variable Cost ComponentsHigh proportion of fixed costs with low capital turnover.Own right-of-way by purchasing or leasing land and constructing the pipeline and pumping stations along the right-of-way.Prope
30、rty taxes,amortization of depreciation,the return to investors,and preventative maintenance all contribute to the high ratio of fixed to variable expenses.Fixed V.S.Variable Cost ComponentsThe terminal facilities of pipelines contribute to the high level of fixed costs.No vehicle helps to explain th
31、e low variable costs,because vehicles are frequently a major source of variable expense.Labor costs are very low in the pipeline industry because of the high level of automation.RatesPricing is uniqueThe nature of operation(one-way movement,limited geographic coverage of points,limited products,etc.
32、)provides little opportunity to provide differential pricing practices.Minimum shipment sizes,usually called tenders,are required;these range from 500 barrels to 10,000 barrels(one barrel equals 42 gallons).RatesPipeline rates are very low,which is reflected in the fact that they carry more than 20
33、percent of the total intercity ton-miles and receive only about two percent of the total revenues.One gallon of crude oil can be sent from Texas to New York for only 1.8 cents.Water carrier costs come closest to pipeline costs,in fact,international supertankers have lower costs than most pipelines.W
34、hen considering pipelines with diameters of 30 inches or more,even ocean carriers have difficulty matching pipeline costs.Current IssuesCan have a powerful impact on the environment and the people who live in it.A leak of oil products and chemicals could have disastrous effects.Increases in housing
35、needs could create a situation in which people would live close to the pipelines and be exposed to the effects of a potentially harmful product leak(such as oil or gasoline).Current IssuesEven when people would not be directly affected by a leak,a leak could have a serious impact on wildlife living around the pipeline.However,the overall record of the industry in this area is outstanding.There is a much higher risk of product leakage/damage with oil tankers as evidenced by the number of spills in recent years.