Exercises

1. Answer the following questions:

1.Why is the handling of materials in long lengths always been a problem?

2. What has changed these materials handling problems?

3. Where is the control cabin of the side-loader situated?

4. How many tons of load can the truck pick up?

5.Where can these truck operate?

6. How are these trucks operated?

7. Can lifting heights and fork lengths be made to suit the individual handling problems?

8. How are unit loads such as cases and drums handled?

9. For what operations is the fork-lift truck designed?

10 What truck attachments do you know?

2. Translate the following sentences into Russian:

1. Погрузочно-разгрузочные работы – один из наиболее тяжелых процессов.

2. Универсальные машины, такие как погрузчики и краны, пригодны для работы с различными видами грузов.

3. Для разгрузки пятилючного судна были выделены два портальных крана и несколько автопогрузчиков.

Lesson thirteen

BULK HANDLING EQUIPMENT

Loading and unloading is mechanized in the ships' holds. The lift trucks used for handling cargoes on the quayside are also used below deck.

Now stack pilers in the hold perform all the heavy work. Especi­ally useful for trimming ships' holds is the crawler tractor fitted with sideways-discharging bucket.

This machine discharges to- either side under a headroom of only 6 ft. It can also, of course, discharge at greater height if re­quired.

The overhead loader can dig either at the front or at the rear of the machine. The loader is based on the diesel tractor, and has a bucket capacity, for coke, of 0.96 cu.yd. If required, the loader can be transformed into a general-purpose mobile crane with a lifting capacity of 2000 lb.

PNEUMATIC UNLOADING OF SHIPS

Early mechanical means of discharging grain was by bucket elevator, but in recent years great strides have been made with pneumatic plant. The flexible intake pipes on pneumatic grain plant extract grain from stowages which could never be reached by buckets. They thus obviate most trimming because they will clear decks and ceilings to the last grain. Experience, particularly with floating elevators, has shown that it is possible to construct machines with handling speeds too high for certain conditions since such speeds often depend upon large pipes.

Lighter fittings involve some reduction of maximum hour speeds but often show better average outputs.

Whenever there is a need for rapid and economical movements of bulk materials from one point to another, it can be met suc­cessfully with the handling plant. The handling plant speeds up the flow of bulk materials, it unloads bulk grain from ships at the rate of 400 tons per hour and feeds belt conveyor to storage silos.

MOBILE PNEUMATIC HANDLING PLANT OF MODERATE

CAPACITY

The new design of a mobile pneumatic handling plant has been produced to meet the demand for a handling plant of moderate capacity and has a rating of 50 tons per hour. The capacity rating is specified when handling wheat or other similar materials and when the intake nozzle is sinking vertically and the material flow­ing freely, the intake pipe being 100 ft. long, including a vertical direct lift of 50 ft. long laid horizontally.

The complete plant is mounted on an 8-wheel trailer specially constructed for the purpose. The outside dimensions of the complete plant are as follows: its overall height is 14 ft., width 8 ft., length 18 ft. 5 in. and wheelbase 14 ft. 5 in. The maximum weight is 13Ч2 tons.

The combined grain and dust discharger provides an air seal necessary to maintain a partial vacuum within the system, while allowing material to pass through to the blowing side of the plant. It is fitted with separate inlets for the main grain stream from the receiver and for dust from the internal cyclones. The discharger is driven through a slipping clutch designed to operate a warning system if a foreign body becomes jammed between the rotor and casing. The grain receiver has been specially designed so as to give ample capacity while keeping within the overall height available for the plant. To achieve this, the normal cylindrical receiver has been mounted on its side. The grain inlet, which can be moved through 360 deg., is located at the highest point of the receiver. Grain enters the receiver tangentially so that separation of the larger dust particles is facilitated.

A high efficiency cyclone is built into the side of the receiver and delivers dust to the separate dust inlet of the discharger. As a safety precaution against the possibility of material from the cyclone being drawn over into the exhauster, an air receiver con­taining a fine inesh filter is fitted in the pipe-line from the cyclone. Material accumulating in the bottom of the air receiver can be re­moved through an easily accessible door.

Receiver

Bin level switch

Cyclone Discharger-

Fuel'(acr:

Fig. 10. Outline drawing showing main items and flow of grain

There is an instrument panel which houses indicator lights for engine oil, exhauster oil, discharger oil, discharger clutch, level switch and battery. A vacuum gauge and an air pressure gauge are mounted beneath these indicator lights.

On normal working when discharging from a barge this plant can be operated with one man on the plant and another in the barge. An additional man may be necessary at intervals for trimming and cleaning up, etc.

Fuel consumption for this unit is approximately 8 gal/hr at full load.

WORDS AND PHRASES

stack piler подъемник для складывания груза штабелями

trimming разравнивание

crawler tractor бульдозер на гусеничном ходу

overhead loader подвесное разгрузочное приспособление

bucket capacity емкость ковша

yd. (=yard) ярд {ок. 91см)

bucket elevator ковшевой элеватор

pneumatic plant пневматическая установка

flexible intake pipes гибкий всасывающий трубопровод

obviate f'obvieit] устранять

silo ['sailon] силосная яма

rating зд. производительность

specify определять

nozzle сопло