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Providing effective backup for terminal ‘muscle’Container terminal productivity requiresmore than just the largest, most powerfulequipment, writes Fredrik Johanson

In everyday language, we defineproductivity as metrics and measures ofoutput from production processes per unitof input.

Depending on how a terminal’sperformance indexes are defined,productivity can refer to containers perhour, moves per hour or cost per container,for example. It is not all that difficult tomeasure containers or moves per hour,system suppliers can help a terminal tooperate its dockside cranes faster.

Cargo Systems consulting editor BrianRobinson presents a legitimate argumentthat with “muscle” alone, a terminal can beoperated faster to reduce cycle times and toconsequently increase productivity (CS, Dec08, p43). This typically provides shorterramp times and higher speeds for hoistoperations, as well as optimal results incontainers per unit of time.

However, this approach requires higherinstalled electrical power, with subsequentscaling up of motors, inverters, transformersand cables.

Furthermore, if the terminal does nothave a sufficient number of vehicles toreceive the containers off-loaded from theships, crane hang times will becomeexcessive, resulting in unnecessarily highidling and magnetising losses in motors andtransformers. The anticipated gains from theproductivity increase would be entirely orpartially negated by increased costs for bothoperations and investments.

So what can the supplier of the electricalsystem do to influence crane productivity?Selling larger components – which has anupside for the system supplier – is not agood long-term solution for society as awhole, for the environment or for craneusers.

Automation, training, service andsupport, spare parts, crane informationmanagement systems, preventivemaintenance and integration are examplesof some of the areas in which craneproductivity can be increased.

A function used by some suppliers forseveral years is anti-sway. The functionentails the operator being assisted incatching the sway and can thus focus ontasks other than controlling the sway of thesuspended load. This can be combined withelectronic load control (ELC), with theoperator using a touch screen to choose theposition to which the container or emptyspreader is to move.

Rather than using anti-sway, many craneoperators traditionally prefer to catch thesway themselves, if for no other reason thanprofessional pride, and they are often highlyskilled at this.

Load pendulation in the other direction –the skew direction – is significantly morecomplex for the operator to correct and itbecomes more difficult to stop, the longerthe ropes. An automatic skew control is nowavailable that efficiently ensures that skewpendulation is minimised, and consequentlycontributes to shortening cycle times.

This function can be combined with afunction that determines the position of thevehicle that a container is to be placed on,permitting vehicles positioned at an angle inthe lane to be loaded without delay. Theangle discrepancy between the load andvehicle is regulated to zero by the loadbeing skewed on the way from ship toshore.

The result of automatic skew control is anactual productivity increase, in that thecrane can move more containers per hourbut with equally large frequency convertersand transformers as previously. Moreover,the function assists operators by relievingthem of a very difficult task.

With the help of a stack profiling system(SPS), the crane receives stack profilingdata, which is updated on each cycle fromthe ship. The system can then calculate thelowest possible height of lift. This functionnot only reduces cycle times by the load notbeing lifted higher than necessary, it alsominimises energy consumption, thusreducing the impact on the climate.

Sticklers for detail may object to theargument that the energy used to lift theload is regained during lowering, but it mustbe kept in mind that losses in motors,cables, transformers and gearboxes arenever regained; these losses are only used toheat the planet.

If we now combine anti-sway, electronicload control, stack profiling systems andautomatic skew control, we get somethingthat ABB calls an automatic containerlanding system (Aclas).

Look no hands!ABB hasproduced anautomaticcontainer landing system(Aclas) thatcombines anti-sway, electronicload control, stack profilingsystems andautomatic skewcontrol

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In brief, Aclas entails the operatormonitoring only the process from the pointwhere the load leaves a safe height over theship to where it reaches a safe load heightover the vehicle, with the correct skew angleand with no pendulation whatsoever. Theoperator can easily set the container on thevehicle and return to the ship for a newcycle.

For a conventional single hoist STScrane, the advantages of such automationsystems are obvious, but these become evenmore so if one studies a dual hoist STScrane where non-beneficial portions of thecycle time can be expended for landingloads on vehicles.With the help ofautomation, which can determine thepositions of vehicles while the crane ismoving from the ship, there are major gainsin time – and subsequently money – to bemade for large and modern STS cranes.

The system supplier can help craneoperators to work much more intelligentlyand economically, and with lower energyconsumption, while shortening cycles.Increasing berth productivity, however,

requires the landside transport of containersto or from the quayside to keep up, but thisis a topic for several doctorial dissertations.

Naturally, the system onboard the cranemust be the best possible and provideoptimal availability, but even so, things cango wrong. And when they do, knowledge ofhow faults are to be remedied must bereadily accessible.

Personnel in maintenance andengineering departments must possess solidknowledge of the system. An STS cranecannot be quickly replaced like a robot on aproduction line; it must be constantlymaintained. This requires skilled personneland management that understand theimportance of time being allotted tomaintenance, modifications or additions.

Because operational priorities at a busybox terminal can naturally cause preventivemaintenance to be postponed, each terminalmust conduct an analysis of its particularsituation – there is no one-size-fits-allsolution – and based on the results of theanalysis, appropriately train its personnel.

Actually, mechanical breakdowns on

cranes are rare; any problems that may ariseare usually caused by minor faults inelectrical systems. System suppliers can helpout by continually improving knowledge ofthe systems through onsite training on thecranes and at strategically selected trainingcentres, for example.

Upon delivery of new equipment ormodifications, participation incommissioning must also be included as apart of training so as to provide terminalstaff with the opportunity to familiarisethemselves with the new equipment.

A prerequisite is that all training isconducted by knowledgeable personnel, whoare not only familiar with the latest advancesin technology, but also have knowledge ofolder systems since, for example, manycrane users have some older cranes withDC technology.

With the right personnel, properly trainedfor the tasks at hand, any downtime can beminimised and productivity maintained orimproved due to the personnel beingknowledgeable of the system.

Regardless of the skills, training andsystem familiarity of the maintenancedepartment or whether maintenance iscorrectly conducted, support from thesystem supplier for an STS crane systemmay be necessary. First of all, this requiresthat such support exists, that it isaccessible, and not least, that it iscompetent.

As a crane user, one must demand thatthe system supplier fulfils theserequirements.Without this, crane availabilitycan be negatively affected, andconsequently, productivity. The provision ofservice and support are naturally a matter ofbalance with all day, everyday service costlyboth for the crane user and system supplier.

If there is an installation base in thegeographic area, 24/7 support and servicemay be perceived as worth the investmentby both parties since the costs can bedistributed over several installations. Onceagain, this is not a one-size-fits-all matter;each terminal must analyse the situationbased on its unique circumstances.

Reputable crane system suppliers providesupport from crane-certified engineers withdocumented experience in the industry andknowledge of the systems.

The container handling industry is trulyglobal and crane users are often globaloperators with world-class demands onservice, support and spare parts supply.These world-class demands must be met bythe system suppliers and often exceeded ifthey are to remain in business.

STS cranes must be constantly maintained while keeping terminal disruptions to a minimum

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Even if the systems are designed and builtwith considerable demands on quality, spareparts may be needed. Between differentterminals, as well as between operators,there are various philosophies about howspare parts should be purchased and thetype of support the system supplier shouldprovide.

That an operator is global entails thatrumours and information quickly spreadaround the world, and if a supplier hasproblems at one terminal on a continent, itwill not take long before knowledge of thishas spread to other terminals within thegroup. Unfortunately, good news does nottravel as fast. Nonetheless, this helps systemsuppliers to stay on their toes and supplyspare parts in the shortest possible time.

The life cycle philosophy also has aneffect on spare parts management, and notleast, on the costs for spare parts.

Crane users must demand that theirsystem suppliers have a plan for theproducts’ life cycles, for how obsoletesystems and components are to be replacedin the future, and to ensure that newproducts are backward compatible witholder products to a reasonable degree. Acustomer does not want to buy a system,only to be informed a few years later thatthe investment is now obsolete and that theprice of spare parts has skyrocketed.

Spare parts management, and service andsupport go hand-in-hand, and with goodsupport and efficient spare partsmanagement at a level selected by the craneuser, the system supplier has anunquestionably positive effect on theproductivity of an STS crane. Moreover,this effect applies regardless of whether thecrane is brand new or one that has been inservice for a few years.

Increasingly more technically advancedcranes, perhaps with more automation,require modern maintenance that cansupport a modern crane information

management system (CIMS). A CIMS isnot intended to merely create long lists oferrors; it should also effectively guide theperson troubleshooting to the right locationin the hardware or software documentation.

A CIMS is an important tool for reducingcrane downtime, and a simple and user-friendly CIMS, which is also powerful andintuitive, helps to increase the productivityof STS cranes.

Receiving all information on an onboardcrane maintenance station (CMS) from aland station located in an office or vehicle istoday more the rule than the exception.Artificial intelligence systems that learn fromtheir experiences are surely the dream forthe majority of crane engineers andmaintenance technicians.

Three-dimensional views in the landstation over the docks and cranes are nowroutine and add additional information inthe form of even better overviews of thecranes.

Even if a system supplier is able to buildsystems that are technically advanced, easyto maintain, inexpensive and that provide ashigh availability as possible, theynonetheless require maintenance. Thismaintenance is, or should be, movingincreasingly towards working withpreventive maintenance rather than makingrepairs when something fails.

An airplane, or even a modern automobilewith indicator lights for service, is taken in formaintenance at specific intervals regardless ofwhether anything is obviously in need ofrepair. A modern CMS supports this way ofworking and there must be counters, timersand calendars to identify when certain servicetasks are to be conducted.

The system generates histories, plans andreports that effectively support personnel inconducting maintenance at selected pointsin time. Proper maintenance results in fewerunscheduled failures for any device, andconsequently higher productivity. Acorrectly designed and configured CMSgives STS cranes higher productivity.

Moisture, vibrations, dust, electrostaticdischarges (ESD), loose connections andother difficulties in combination constitute atough environment for which to produceelectrical systems, especially when they areto be inexpensive, easy to maintain, and atthe same time, provide high availability.

To a certain extent, it is about choosingcomponents that can withstand theenvironment, especially outdoors, but it alsoinvolves developing in-house componentsthat are designed solely for craneapplications when nothing else on the

Fredrik Johanson is general manager,marketing and sales, for crane systems atABB, Sweden. He joined ASEA (ABB) in1984 as a Systems Design Engineer andhas held several positions in the company.

Johanson has a Bachelor of Sciencedegree in energy engineering fromMälardalen University in Västerås, Swedenand an MBA in project management fromLinköping University of Technology inLinköping, Sweden.

market satisfies the demands placed on thesystem of an STS crane.

System suppliers prefer to undertake fullresponsibility for functionality due to theirextensive experience in manufacturingelectrical equipment for crane applications,resulting in reliable systems with highavailability. Such systems should bemodularly designed, easy to work with,electrician-friendly and have properdocumentation that is prepared aftercommissioning and then preferably enteredinto a CMS for quick and efficienttroubleshooting as necessary.

The integration concept also encompassesresponsibility for the correct dimensioningof transformers, frequency converters andmotors based on data provided, but also thatthe designs are based on the energyconservation approach with, for example,energy-efficient motors, good engineeringpractices, optimally sized equipment,sectioning of floodlights – the list is long.

Even in the integration of STS cranesystems, the system supplier influences theproductivity of STS cranes. cs

Using a crane maintenance station in an office orvehicle is now more the rule than the exception

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