It is designed ... To be transported – она сконструирована

транспортировки

clearance ['kl.ardns] промежуток, зазор

pile - складывать в штабеля

set - штучный груз или группа одинаковых штучных грузов

land conveyance -сухопутные транспортные средства

self-stacking - самоукладызающий

forepart from

the truck driver так как кроме водителя азто- погрузчика

pre-slingingпредварительное застропливание

turn-roundоборачиваемость

save, all net предохранительная сеть

to sling (slung) подвешивать

to prevent packages falling on для того чтобы предотвратить

выпадение пакетов

hull - корпус gapщель, промежуток

EXERCISES

I. Answer the following questions:

1. What is the commonest form of cargo handling gear?

2. Where is the sling used?

3. How is the sling made?

4. When does the sling automatically tighten and bind the set?

5. What should be done in order to ensure that the bight of the. sling will not slip?

6. What are slings made with?

7. What is the effective length of the sling?

8. What does the size of the sling depend upon?

9. When are slings especially valuable?

10. What is the cargo net?

11. What are cargo nets used for?

12. In what cases are circular net boards used?

13. What is the cargo tray made of?

14. What is the purpose of the raised edges?

15. What is the pallet?

16. What is the pallet designed for?

17. May the pallet be regarded as self-stacking?

2. Analyse the following sentences:

   1. This new design of pallet can be fork-operated from all sides, both top and bottom.

   2. Stillages and pallets provide a speedy, compact form of mechanical handling.

2. Form nouns and adjectives (or participles) from the follow­ing verbs and translate them into Russian:

store, operate, combine, travel, press, stretch, handle, stack, fall, break, slip, widen, crush, suit, consider.

2. Translate the following sentences into English:

1. Эти устройства предназначены для подвешивания и захва­та груза. 2. Крюк и грузовая петля являются универсальными грузозахватными устройствами. 3. Для перегрузки штучных гру­зов применяются стропы, грузовые площадки, грузовые сетки.

4. Для насыпных грузов применяются ковши различного типа.

5. Стропы для штучных грузов делаются из стальных или пенько­вых канатов или цепей. 6. Бригада будет выгружать мешковой груз грузовыми площадками. 7. Для перегрузки бочек будут при­менены грузовые сетки. 8. По специальному заказу морского флота будут изготовлены нейлоновые сетки, прочные, легкие и износоустойчивые, для подъема груза. 9. В трюм одновременно загружали два стропа или две универсальные площадки. 10. На каждую площадку они укладывали по 12 мешков. 11. Один груз­чик должен быстро передать конец стропа другому. 12. Больших успехов в этом году добились ленинградские портовики. 13. Они применили различные усовершенствованные грузозахватные уст­ройства. Это не только облегчило условия работы, но значи­тельно повысило производительность труда. 14. Рационализато­ры и конструкторы постоянно создают новые грузозахватные устройства. 15. Выбор средств механизации погрузочно-разгрузочных работ зависит как от вида груза, так и от типа транспорт­ных средств. 16. Использование площадки значительно повысило производительность труда. 17. Вилочный автопогрузчик захватил площадку с 10 пакетами целлюлозы. 18. Применение площадок сократило потребность в стропах. 19. Стремясь механизировать трудоемкие процессы, портовики Владивостока сами изготовили много площадок для пакетных перегрузок. 20. Новая система погрузочно-разгрузочных операций ускорила оборачиваемость судов.

Lesson six

CRANES

Cranes are suitable for an enormous variety of jobs, and are available in many types and a wide range of capacities. Practically almost all modern dock and wharf cranes are driven by electricity or hydraulically operated. Capacity depends entirely upon the nature of the goods to be handled, but for the ordinary mixed cargo a capacity of 3—5 tons per lift has been found most convenient.

With specially heavy classes of goods higher-powered cranes are, of course, required and this can be met by having available floating cranes of 10 to 100 tons capacity, which can be brought to the ship or quay where such special loads are required to be handled.

In other cases, high capacity can be provided, but this generally involves moving the ship when a heavy load has to be handled. Should a ship be lying at the quay where the heavy lift crane is situated, the crane is not available for any other ship unless both are moved.

During recent 30 years there has been an enormous increase in the numbers and in scope of application to modern industry, of heavy lift mobile cranes. This is partly due, no doubt, to the advent of the diesel engine and its ready adaptability to electric transmis­sion, coupled with the fact that no fuel is consumed during periods of slackness.

Remarkable strides have been made within the last 30 years in the design of electric cranes. With moderate lifts, goods can be handled at fairly high speeds.

DEVELOPMENT OF THE QUAY CRANE

It is interesting to trace very briefly the development of the quay crane, which is quite in a class by itself among a great variety of cranes and lifting appliances. Its prototype was a very crude affair, consisting of little more than a winch and a fixed jib. Progress in crane design was slow before the advent of steam- propelled vessels, because in the old sailing ship days, time was not a factor of importance, and there was no call for expeditious methods of loading and unloading. Manual labour was considered quite sufficient for all quayside requirements.

In the year 1864 hydraulic power was applied to quay cranes. This gave a considerable impetus to quay crane design, and led to a very extensive increase in the cranage equipment of docks and harbours. Then, in the last decade of the nineteenth century, the electric crane appeared. It cannot be said that the hydraulic crane has been altogether displaced. It is still regarded as a most useful appliance. For slow heavy uniform lifts, it presents advantages of no inconsiderable value.

In the lighter, rapid and variable class of work associated with the handling of merchandise, the electric crane is able to function more economically and efficiently.

The principal development in quay cranes design has been in reference to the jib.

Perhaps the most striking feature of the modern quay crane is the luffing motion of the jib, by which it is able to move inwards and outwards in a straight line, as contrasted with the radial action of a fixed jib. This arrangement has been devised for the purpose of avoiding contact with ship's gears, rigging and other obstruc­tions, when working in a restricted areas. But the luffing action of the jib, as at first introduced, entailed a lifting of the load suspend­ed from the jib, due to the raising of the jib head during the inward movement.

This lifting was not only superfluous in action, but it was w asteful of power, and consequently uneconomical. Various expedi­ents were attempted to counteract the effect, and some very in­genious designs have been put forward.

QUAY CRANE REQUIREMENTS

There are certain essential points to be specified in the design of a quay crane. These may be briefly discussed as follows:

Capacity. The average draft, or parcel, of goods from a ship's hold does not exceed 1—2 tons.

A large number of quay cranes, however, have maximum capa­cities as high as 5 tons. Even in the case of an electric crane, where the consumption of current is exactly proportional to the load lifted, it has to be borne in mind that the more powerful the crane, the greater the initial outlay, and, if much in excess of requirements, there will be a corresponding unremunerative investment of capital. Moreover, the additional power capacity involves additional struc­tural weight which has to be moved whenever the crane is slewed.

Motions and Motors. The motions required in a quay crane are four in number: (1) Travelling along the quay; (2) Hoisting and lowering the load; (3) Slewing the jib, and (4) Luffing the jib.

All these motions are provided by separate motors, which work independently.

It is possible, of course, to work all these motions by a single motor, and it can be done quite satisfactorily, but the multiple motor system is more common, being, on the whole, more reliable, and also more speedy, as the time taken to change gears and clutches is saved.

Speed. The ideal motor speeds are those which correspond with the rate of goods handling at the point of feeding and at the point of distribution. The depth of the hold governs the requirements to some extent, and the speed should be greater for a deep ocean liner than for the shallower coasting vessels or inland waterway craft.

WORDS AND PHRASES

enormous [i'no:mas] огромный

range [гешёз] диапазон

hydraulically [hai'drorlikoli] гидравлически

this can be met by having available floating cranes этого мож­но добиться, имея в наличии плавучие краны