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I. 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?
II. 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
is sinking vertically погружается вертикально
vertical direct lift вертикальный подъемник
overall height наибольшая высота
trailer прицепная тележка
dimensions размеры, показатели
dust discharger пылеуловитель
seal затвор
inlet отверстие, вход
cyclone ['saikloun] циклон
foreign ['form] посторонний, инородный
jammed сжатый
grain receiver зерновой резервуар
ample вполне достаточный
tangentially [taen'd3en^3h] по касательной
exhauster всасывающий вентилятор
mesh filter сетчатый фильтр
vacuum gauge [geidg] вакуумметр
air pressure gauge воздушный манометр
gal. (= gallon)галлон (мера жидких и сыпучих тел; англ.= =4,54 л; амер.=3,78 л)
EXERCISES
I. Answer the following questions:
1. Is loading and unloading mechanized in the ships' holds?
2. What machines are used below deck?
3. What machines perform all the heavy work in the hold?
4. What is especially useful for trimming ships' holds?
5. What is the bucket capacity of the overhead loader for coke?
6. What were early mechanical means of discharging grain?
7. What is used for rapid and economical handling of bulk materials?
8. What extracts grain from stowages on pneumatic grain plant?
9. At what rate does the handling plant unload ships?
10. How is the capacity rating of a handling plant specified?
11. What are the dimensions of the handling plant?
12. What is its maximum weight?
13. What is a slipping clutch designed for?
14. How is the grain receiver designed?
15. Where is the grain inlet located?
16. How does grain enter the receiver?
17. What is fitted in the pipeline from the cyclone?
18. How can material accumulating in the bottom of the air receiver be removed?
19. Where are the vacuum gauge and the air pressure gauge mounted?
20. What is the fuel consumption for this unit?
II. Analyse the following sentences:
1. As a safety precaution against the possibility of material from the cyclone being drawn over into the exhauster, an air receiver containing a fine mesh filter is fitted in the pipeline from the cyclone.
2. To achieve this, the normal cylindrical receiver has been mounted on its side.
III. (a) Give nouns corresponding to the following words:
awkward, to perform, discharge, to elevate, long, mechanized, rapid, to serve, economical, to handle, to use, to depend, to justify, frequent, to approve.
(b) Form adverbs from:
practical, easy, immense, frequent, suitable.
(c) Form nouns from the following verbs:
act, construct, assist, fulfil, develop, refer, depend, differ, cost, adopt, measure, press, arrange, appear, deliver, descend, employ.
IV. (a) Give synonyms of the following words:
to remain, frequently, profound, air, to return, incorrect, final.(b) Give antonyms of the following words:
usual, to approve, likely, equal, to appear, visible, to continue, possible, safe, modern, to elevate, to build.
V. Translate the following sentences into English:
1. В этом порту были проведены испытания трюмной машины для штивки насыпных грузов. 2. По погрузке угля она показала хорошие результаты. 3. Для разравнивания насыпных материалов в трюмах морских судов применяется трюмный погрузчик. 4. Погрузчик, применяемый в трюме судна для подачи груза из подпалубного пространства и а просвет люка, значительно сократил время выгрузки. 5. В нашем порту есть шесть трюмных погрузчиков. 6. Сыпучие и навалочные грузы мы будем выгружать одноковшевыми погрузчиками. 7. Для штивки груза в трюме № 1 был применен легкий бульдозер. 8. В трюм был опушен погрузчик, весящий приблизительно 6 г и имеющий ковш емкостью 0.57 куб. м. Производительность такого погрузчика 10 т/час. 9. Новая модель гусеничного одноковшевого погрузчика изготовляется в настоящее время. 10. Первые плавучие пневматические перегружатели были созданы в конце XIX в. 11. Известно, что пневматические установки в настоящее время получили большое распространение. 12. Зерно в нашем порту будет перегружаться пневматической установкой производительностью 200 м/час. 13. Судно было разгружено пневматическим плавучим элеватором. 14. Благодаря применению гибких шлангов пневматическая установка проникает в места, трудно доступные для других типов машин. 15. Перемещение насыпного груза осуществляется по трубам струей воздуха. 16. Они выгрузили зерно из баржи в силос посредством пневматического перегружателя. 17. Всасывающий трубопровод состоит из горизонтальной части длиной 4,5 м и вертикальной части длиной 4 м. 18. Зерно поступает из перегружателя в циклон, находящийся над весами.
19. Транспортировка материала из трюмов судов передвижной пневматической установкой повышает производительность труда.
20. Для выгрузки зерна пневматическая установка является одним из наиболее совершенных устройств.
Lesson fourteen
CONVEYING AND ELEVATING MACHINERY
Modern conveying and elevating machinery is very varied, but we need only describe the machinery used in docks and wharves.
This consists of elevators, gravity or other lowerers, stacking machines, conveyors, belt or other, electric trucks and grain suction plant.
As regarded elevators and lowerers from ship to shore and vice versa, their adoption originated in an endeavour to mitigate the loss of power involved in the use of the ordinary quay crane, which had to lift its load from the bottom of the ship's hold to a considerable height (to clear the ship's hatches and gear) and consequently to a height very much above the quay or delivery level. The energy stored by lifting the load to this height by a crane is then dissipated by lowering the load to the quay level, from which it has to be removed into shed, or to railway truck or road vehicle, by trucking.
The elevator, on the other hand, only has to lift the load to the height slightly above that of the top of the hatch coamings, from which, after a short horizontal travel, it descends to the quay or delivery level by means of a lowerer. The energy stored by raising the load to the necessary height is by this means employed to carry it to a considerable distance by gravity and part of this energy can be employed, by means of suitable electrical arrangements, in driving the elevator.
A still greater advantage in this respect can be obtained when loading, as the goods have to be raised by an elevator from the quay level to hatch level, and then descend on a lowerer into the hold, to a much greater depth than the distance from quay to hatch.
There are a great number of forms of elevators, conveyors and lowerers, but it is only intended here to refer to those types which are most suitable for dock and wharf work.
The types used for general cargo work are gravity roller conveyors, belt or band conveyors, slat conveyors, and canvas sling conveyors; inclined belt elevators or lowerers and stacking machines.
The gravity roller conveyor consists of a steel framework carrying a number of rollers. It is made in sections and is easily portable, and curved sections are provided for running round corners.
The inclination at which these conveyors will work depends upon the weight of the cases or other goods being delivered, but with heavy cases they will work at a very flat inclination.
Band conveyors are used for grain, coal, or other bulk cargoes, but they can be, and frequently are, used for cases, within certain limits.
Slat conveyors consist of series of transverse slats, either attached to some form of belt or to pitch chains working on chain pitch wheels at the driving end. Slat conveyors are suitable for the continuous delivery of mixed packages. For inclined work they may be fitted with small projections to push the cases up. There are various types of slat conveyors depending upon specific handling requirements. These include belt and slat machines as well as chain and rod conveyors and elevators.
Finger-tray or prong elevators and lowerers consist of a series of prongs or trays attached to or projecting from endless pitch chains.
The prongs of such elevators can be arranged to pass through slots In staging in the hold, so as to pick up packages from such staging, to which the packages may have been delivered by skids or shoots.
Canvas sling machines are adapted to act either as elevators, lowerers or conveyors, and will handle a great variety of goods, probably more different forms of packages than any other single machine.
A canvas sling machine consists of a steel framework, mounted on wheels, carrying a pair of endless chains driven by an electric motor. Cross bars between these carry suspended canvas slings, the depth and the weight of which depend upon the nature of goods to be handled.
WORDS AND PHRASES
Elevating грузоподъемный
elevator ['eliveita] элеватор, грузоподъемник
gravity lowerer гравитационный спуск
adoption [a'dopjn] введение
to originate [a'ridgineit] брать начало
endeavour [in'deva] попытка
to mitigate умерять
to dissipate растрачивать
hatch coamings ['koumigz] комингсы люков
to descend опускаться
gravity roller conveyor гравитационный роликовый конвейер
belt (band) conveyor ленточный конвейер
slat conveyor пластинчатый конвейер
frame work рама, станина
roller ролик
portable портативный, переносимый с места на место, передвижной, съемный, разборный
curved закругленный, изогнутый
transverse slats поперечные пластины
pitch chain цепь для зубчатых колес, цепная передача
chain pitch wheels система зубчатых колес
projection выступ
chain conveyor цепной конвейер
prong зуб,зубец; рог
slot выемка, впадина (зубца)
EXERCISES
I. Answer the following questions:
1. What kinds of conveying and elevating machinery are used in docks and wharves?
2. What is the gravity lowerer?
3. What types of machines are used for general cargo?
4. What machines are used for bulk cargo?
5. What does the gravity roller conveyor consist of?
6. Is the gravity lowerer easily portable?
7. What does the inclination at which these conveyors will work depend on?
8. For what kinds of cargo are band conveyors used?
9. What do slat conveyors consist of?
10. What do finger-trav or prong elevators and lowerers consist of?
11. What do canvas sling machines consist of?
II. Analyse the following sentences:
1. They would obtain economy in handling if their movement is assisted by gravity.
2. If they use the force of gravity to move materials, it will be highly efficient as very often no equipment is necessary.
3. This type of conveyor is being more and more widely used because it consumes little power.
III. (a) Form adverbs from:
practical, easy, immense, frequent, suitable.
(b) Form nouns from the following verbs:
act, construct, assist, fulfil, develop, refer, depend, differ, cost, adopt, measure, press, arrange, appear, deliver, employ.
(c) Form verbs from the following words:
varied, stacking, adoption, origin, considerable, arrangements, suitable, continuous, projecting, endless, handling.
IV. Translate the following sentences into English:
1. Элеваторы — это машины, перемещающие груз в вертикальном или наклонном направлении. 2. Прототип современного элеватора использовался в странах Древнего Востока для подъема воды около 3000 лет тому назад. 3. Элеваторы для сыпучих грузов впервые были применены в XVI в. 4. Гравитационными устройствами называются такие, в которых движение груза осуществляется под действием силы тяжести. 5. Простейшим гравитационным устройством является наклонная плоскость. 6. Для вертикального спуска применяются ступенчатые спуски. 7. Роликовые спуски применяются для перемещения штучных грузов под малым углом наклона. 8. Роликовый спуск представляет собой раму с установленными на ней роликами. 9. В гравитационных устройствах для сыпучих грузов грузы перемещают по желобам или трубам. 10. Трубы изготовляются из листовой стали, редко из дерева. И. В ленточных транспортерах материал перемещается непрерывной лентой. 12. Ленточные транспортеры имеют самое широкое распространение. 13. Они применяются в портах наряду с кранами для погрузки судов, железнодорожных вагонов и автомашин. 14. Ленточные транспортеры широко применяются на складах и в трюмах. 15. Конвейеры перемещают груз как по вертикали, так и по горизонтали. 16. Уголь поступает по конвейеру в трюм судна. 17. Стрела новой конвейерной установки опускается в рабочее положение над трюмом. 18. Штучные грузы из трюма № 2 будут подавать на конвейер. 19. Пластинчатые транспортеры применяются на складах, а также при погрузке и выгрузке вагонов. 20. Ленточные конвейеры применяются для перемещения как насыпных, так и штучных грузов. 21. Пластинчатые конвейеры предназначаются преимущественно для руды, камня, отливки, поковки и пр.
Lesson fifteen
NON-FIXED CONVEYORS AND ELEVATORS
This is a survey of mobile conveyors or elevators, portable and transportable conveyors, and equipment.
The greatly increased popularity of non-fixed continuous handling equipment, such as mobile conveyors and elevators, portable conveyors and transportable conveyors, and elevators, has of recent years stimulated the development of large numbers of new- type machines and of variations of long-established models. Both are now generally available at short notice.
What is a portable conveyor? What is a mobile conveyor?
Portable conveyors or elevators are lightweight or ultralight- weight machines. Machines of this type include the following: gravity roller conveyors; skate wheel conveyors; flat belt conveyors; troughed belt conveyors; slat conveyors; and worm-type elevators.
Portable machines in common use from light-alloy roller conveyors light enough to be picked up and carried in one hand, to a variety of belt conveyors and worm-type elevators.
Mobile conveyors and elevators include belt and slat conveyors and elevators, steel band conveyors, bucket elevators, screw and worm conveyors and elevators, pneumatic conveyors and elevators, vibratory conveyors and elevators, gravity roller conveyors, ship's elevators-conveyors, large unloaders, and many other types of equipment.
The majority of mobile conveyors and elevators are for the handling of loose materials such as coal, coke, gravel, sand, etc., or for the handling of packages, sacked materials, boxes and the like.
These machines, in the main, are forms of fixed-or variable-discharge height conveyor and they employ, as a rule, belt or slat conveyor mechanisms. Some of these machines are reversible and may be used as horizontal conveyors. Three main size and weight categories may be defined.
Height adjustment may be by hand-operated winch or hand- powered hydraulic ram, by electric winch or motor-driven screw, or by power-operated hydraulic rams.
It is well known that heavy machines are less mobile than light or medium machines and that the overall weight of a machine will be a function of its length and discharge height as well as load capacity. For several purposes, e. g. stacking raw materials, a light or medium machine might be required to have an extra- high discharge height.
In each size and weight category there are two kinds of conveyors: machines designed for handling unit loads, and machines designed for bulk materials handling. Light machines of the unit- load type will handle unit loads of up to about 100 lb. Light machines of the bulk materials handling type are for occasional duties and will handle relatively low tonnages without difficulty. Medium unit-load machines will handle unit loads up to about 200 lb., i. e. as much as can be handled by one strong man or by two average men. They may be used in conjunction with roller conveyor hoists, cranes, and other handling aids. Medium machines designed for bulk materials handling may be fitted with 18-in. to 24-in. belts. They are suitable for heavy and continuous duties. Heavy machines of both types are often self-propelled. Such machines will handle unit loads of 200 lb. and upwards. And, for handling bulk materials, they may be fitted with belts of width as great as 36 in.
WORDS AND PHRASES
survey ['ss:vei] обзор
transportable [traens'pD:t3bl] переносной
of recent years за последние годы
variations of long-established models модификации уже давно существующих типов
at short notice скоро
ultra- ['лйгэ]приставка:сверх-
lightweight легковесный
roller ['roula] конек на роликах
flat belt conveyor ленточныйконвейер с плоской лентой
troughed [troft] belt conveyor бросковый ленточный конвейер
worm-type elevator винтовой элеватор
bucket elevator ковшевой элеватор
screw and worm conveyor elevator винтовойконвейер, элеватор
vibratory conveyor ['vaibratari] вибрационныйконвейер
gravel гравий
sand песок
sacked material мешковой груз
hydraulic [hai'dro:lik] ram гидравлический поршень
EXERCISES |
I. Answer the following questions:
1. What is a portable conveyor?
2. What is a mobile conveyor?
3. What do mobile conveyors and elevators include?
4. For what purposes are standard mobile conveyors and elevators used?
5. What types of conveyors do you know?
6. With what belts are medium machines for bulk materials handling fitted?
7. What belts are heavy machines fitted with?
8. What duties do medium machines for bulk materials perform?
II. Analyse the following sentences:
1. Any equipment which reduces the cost of load handling must be used in our ports.
2. The conveying to ship's side is done by fork lift trucks.
III. What are the functions of the -ing forms in the following sentences? Translate the sentences into Russian:
1. In this conveyor the top and bottom surfaces of the steel band are used for carrying the load. 2. Many other operations can be carried out whilst conveying. 3. A new book showing how new production methods can improve efficiency will be published next year. 4. The productive capacity of the existing personnel and machines has been increased by 30 per cent. 5. That installation was put into operation at the beginning of last year and high average loading capacities of up to 500 tons/hr were reached. 6. This means that a 10,000-ton vessel can leave the port after only 20 hr. berthing time.
IV. Translate the following sentences into Russian:
1. The designers should study the influence of handling techniques upon ship design, 2. We said that we should use portable lifts to save space. 3. The handling of materials in a store or warehouse should be such that the maximum utilization of space be accomplished with minimum effort. 4. Economy should be obtained by the maximum utilization of equipment. 5. They said that they had overcome handling difficulties in warehouse building. 6. Materials should be handled by the cheapest method. 7. We should investigate some of the drawbacks of this equipment.
V. (a) Form adjectives from:
mobility, pneumatically, industry, difficulty, method, centre, use, dynamo, economy, magnet, advantage, wire, vibrator, reverse.
(b) Give nouns corresponding to the following verbs:
base, lose, adjust, move, agree, instruct, extend, differ, depend, refuse, explain, resist, act, create.
VI. Translate the following sentences into English:
1. Для погрузки и разгрузки судов, железнодорожных вагонов и автомобилей, а также для штабелирования грузов на складах широко применяются разнообразные типы передвижных конвейеров. 2. Транспортеры — это машины, перемещающие груз по горизонтальному и наклонному направлениям. 3. Транспортеры не могут применяться для подъема груза. 4. Передвижные ленточные транспортеры применяются главным образом для сыпучих грузов и обычно имеют длину от 5 до 20 м. 5. В настоящее время в портах еще широко применяются старые типы передвижных ленточных транспортеров. 6. Наиболее распространенным типом является наклонный транспортер. 7. Для внутритрюмных работ в судах применяют специальные транспортеры в виде переносных легких секций длиною 2—4 метра. 8. Устройства, в которых перемещаемый материал движется под действием силы тяжести, являются наиболее экономичными транспортными средствами для опускания груза. 9. Ленточный транспортер впервые появился в XVIII в. 10. Стационарные и передвижные ленточные транспортеры были применены в промышленности в 1860 г. 11. На зерновых, угольных и рудных причалах широко применяются машины непрерывного транспорта, главным образом ленточные транспортеры. 12. В портах конвейеры встречаются редко. 13. Элеваторы для штучных грузов применяются на складах для перегрузки и подъема мешков, бочек, ящиков. 14. Ковшевые элеваторы применяются для перегрузки и подъема насыпных грузов. 15. Скребковые транспортеры применяются для перемещения как сыпучих, так и штучных грузов на малые расстояния. 16. Машины непрерывного транспорта получили интенсивное развитие в начале XX в. 17. Винтовые конвейеры служат для перемещения насыпных грузов обычно на небольшие расстояния. 18. Для развития современной техники в области производства конвейеров характерна тенденция к созданию новых модификаций уже существующих типов.
Lesson sixteen
STANDARD PORTABLE, MOBILE AND TRANSPORTABLE
CONVEYORS
Large numbers of specially designed mobile, portable and transportable machines have been developed over the years.
The demand for some of these has been great enough to justify their production as additions to the range of standard models. For this reason the machines of this type consist of specially designed coal-handling conveyors; bulk materials conveyor-loaders; ship- loading conveyors; stack pilers; grain-handling conveyors; machines which throw bulk materials on to stock piles or into ships' holds; conveyors designed to operate under extremely dirty air conditions; extra-large loading hopper-type bulk materials conveyors; telescopic roller conveyors; gravity roller conveyors light enough to be carried in one hand; agricultural-type conveyors which may be altered at will to handle bulk materials, bales, cartons, etc., heavy-duty industrial-type belt conveyors, which may be altered at will from troughed belt to flat belt machines; numerous special type worm conveyors and pneumatic conveyors.
Mobile conveyors are, wheeled machines. Non-fixed conveyors and elevators include: (a) bag and package stacking conveyors, (b) conveyors and stackers for bulk materials, and (c) throwers for bulk materials.
The stacking conveyor is a mobile inclined belt conveyor and is mounted on front wheels and rear castors and is driven by a 3/4 h. p. totally enclosed electric motor, through 30 ft. of trailing cable. Two models are available: one is 10 ft. long and has a lift which is variable between 4 ft. 6 in. and 6 ft., the other model Is 12 ft. long and has a lift of 5 ft. to 8 ft. In either case, the angle of elevation is varied by operation of a self-sustaining quick-screw lifting gear. A rubber-faced belt is employed. This enables bags and packages to be elevated up quite steep angles of inclination without damage.
This conveyor is useful for indoors duties and work out of doors, for warehouse stacking and for lorry loading and unloading. It can handle 1 cwt. or 2 cwt. bags as fast as they can be loaded.
STACKING MACHINES
These machines enable the whole of the headroom in a shed or warehouse floor to be utilized without the labour of stacking bales, sacks, or boxes to a considerable height by hand. An inclined band conveyor can be used for this purpose, provided the inclination is not too steep.
A continuous inclined stacking machine of the slat type stacks sacks. When stacking sacks, it is important to secure a "bond" by stacking the sacks alternately as headers and stretchers. If stacked in regular walls there is a risk of a wall of sacks corning down, which might easily cause a serious, even fatal, accident.
The machine occupies very little space, and when the package has been hoisted to the required height it is pulled off the platform into tier.
This machine can be used for breaking down the tiers, for removal of the goods, and then acts as a lowerer.
Sacks and similar light packages are lowered from the stacks by means of wooden shoots.
Stacking can also be done by means of electric runabout cranes.
MOBILE STACKERS
Mobile stackers for bulk materials such as coal and coke are very well known. Five types of machines are made. These are as follows: light tubular-construction bulk stackers; mobile horizontal conveyors; bulk stackers; bulk loaders; and special machines of various kinds.
A typical light tubular bulk stacker is easily handled by one man, and among the points of interest to be noted are the use of castor wheels at the feed end, the towing bar at the delivery end, and the very full stream of bulk material cargo being delivered. Light tubular stackers are of two types: fixed delivery height machines, and variable delivery height machines. The latter have screw-operated self-sustaining variable height adjustment. The fixed-height machines can deliver at any level within the limits of a variable height machine.
THE BULK LOADER
The bulk loader is a form of a mobile bulk materials hopper combined with a short length of belt conveyor and terminating in a discharge chute suitable for delivery of bulk materials on to a belt conveyor or elevator. Operation is by diesel engine and discharge height adjustment is carried out by powered hydraulics.
The hopper capacity is sufficient to enable 4'/2-ton wagons to be tipped whilst the loader and its associated stacker are running at normal speed. Normal handling capacity is 120 tons/hr, using a 24-in. belt.
Higher load capacities may be obtained by speeding up the belt of the stacker or by providing a wider belt.
WORDS AND PHRASES
coal-handling conveyor конвейердляперегрузкиугля stack-piler штабелеукладчик hopper загрузочизяворонка, ковш SUPPLEMENTARY TEXTS
To be read after Lesson 2.
Ships have to visit ports very frequently, especially those in remote parts of the world, which are quite inadequately provided with quayside appliances. It has been found necessary to equip vessels with a certain amount of cargo handling equipment, which varies very considerably in extent. Most modern vessels are provided with installations of sufficient extent and capacity to enable them to dispense almost entirely with extraneous aid in loading and unloading operations. The fact that this equipment is available and can be used at far less cost than the charges for crane hire, causes it to be put into operation even at ports which are well provided with quayside appliances. Sometimes the equipment works unaided but not infrequently it uses the quay cranes as an auxiliary.
A ship's cargo handling equipment consists of masts, derrick booms, pulleys, blocks and winches. In addition, there may be cranes. The gear is arranged, naturally, at holds, or hatches, being combined in groups suitable to deal with each opening.
To be read after Lesson 5.
For speedy and efficient cargo handling the tubular steel pallet is now being used.
The pallet, fabricated from welded steel tube, combines great strength with lightness. When not in use, the pallets nest one inside the other, and a stack of 16 only equals the height of four ordinary timber pallets.
The pallets are designed for 4-way entry of fork lift trucks, and lifting by crane is also simplified; the special sling has two bars which engage with slots at each end of the pallet.
These are designed so that although the bars can be quickly disengaged when the pallet is in position, it cannot fall from the lifting gear if it meets an obstruction while it is being hoisted or lowered.
It can be quickly fitted for goods of irregular shape, vertical posts or side panels.
To be read after Lesson 7.
HYDRAULIC LUFFING GEAR ON DOCKSIDE CRANE
The new dockside crane uses hydraulics for the luffing gear. This is a great step forward in crane design, because the weight of the luffing gear is reduced to about a quarter.
Filtered oil from the reservoir is pressurized to the working circuit pressure of approximately 1000 lb/sq.in. by a series gear pump driven by an electric motor. Oil from the pump passes through a microfilter, which may be by-passed in the event of a blockade, to a multi-port directional valve. This is manually con
trolled by the crane driver and is linked to a second directional valve mounted on top of it. Oil flow from the main directional valve passes through a pilot-operated non-return valve to the appropriate end of the luffing cylinder. Exhaust oil is returned to the valve via a second pilot-operated non-return valve. A flow limiting valve is included in the return line from the main directional valve to the reservoir. The pilot-operated non-return valves are controlled by the second directional valve, and operate on a take-off pressure from the main circuit pressure relief valve, situated down-stream from the microliter. The valve is also designed to unload the pump when both directional valves are in the central position.
The operation of the luffing cylinder is of particular interest. The cylinder has four operated ports. Non-return valves are included in the supplv line to Fig. H. The lifting cylinder on the dockside the outermost ports crane is controlled ЬУ hydraulics
and these permit oil
flow only into the cylinder. The flow through the other two ports is controlled by two pilot-operated non-return valves. One of these is set to allow oil to flow into the cylinder, the other to allow oil to escape. To move the cylinder from its extreme position, oil is fed through the outer supply port until the piston passes the inner supply port.
As a safety measure the luffing cylinder has been designed to incorporate the associated non-return valves. This ensures that the mechanism is protected in the event of power or pipe failure.
To be read after Lesson 8.
3-TON LEVEL-LUFFING TRAVELLING QUAY CRANE
The gantry has four legs of box section which carry the necessary ballast inside. It was considered that four legs offer the best operating conditions, particularly in regard to stability and to wheel pressures on the quay. The legs are shaped to avoid the accumula-
10 А. В. Викторов, Л. В. Василенко
tion of water and dust so as to obviate untimely wear of the point and the steel.
Fig. 12.Two 3-ton level-luffing travelling quay cranes. In the right-hand picture one oi these cranes is shown with the jib luffed down to the quay for inspection of maintenance |
There are no low-placed horizontal connecting beams between the legs, so that railway trucks, lorries, fork trucks, trolleys, etc, can easily pass under the crane between the legs in all directions. Two of the four bodies are driven by self-contained, shock absorber fitted travelling mechanisms which can be easily dismounted for inspection or overhaul and remounted afterwards.
A new feature of the crane is that the jib can readily be luffed down to the quay. This makes it very easy to inspect sheaves, ropes and the wire rope-protection device over the top sheave, to see if the greasing needs attention and to reeve new wire ropes The ease of lowering to the ground tends to ensure that the jib gets more frequent inspections, and this should materially add to the life of the jib and its mechanical parts. To luff it down to the quay, the crane operator has only to release two bolts and push in the button of the by-pass switch of the luffing-limit device.
Riveted construction of the jib was decided upon so that should a deformation of a bar occur through some accident—and these
can happen with even the most experienced operators — it can be repaired on the spot with the minimum loss of time. When there are two cranes on one track the tail ends of the jibs cannot touch each other.
The hoisting mechanism is a self-contained completely enclosed unit fitted to the crane platform at three points.
It consists of an electric motor with built-in brake (which operates as soon as the current is closed) and flexible coupling. Space is saved by the reduction gears being fitted inside the hoisting drum. This simple unit is easily dismounted and taken to the workshop for overhaul. The gears run, of course, in an oilbath. The operator can read the weight of the load with an accuracy of some 98 per cent; this indicator is of the vibrometer type and also acts as overload safety device.
The slewing mechanism is also a self-contained unit of the vertical type, easy to inspect and dismount. Here also a shock- absorber is provided and here, too, there is a three-point attachment. The upper structure slews on and is carried by a ballrace with two layers of balls for taking up pressure and pull. No ballast is necessary in the slewing structure, thus saving weight and space.
The luffing mechanism is a self-contained, easily dismounted unit with three-point attachment to the tower. A shock-absorber prevents extreme shock loads and lessens wear, especially when starting and stopping.
The windows of the cabin provide a "cinerama" view of the quay and the ship, and the driver is seated in a well-designed chair with the controls at comfortable distance and height for his arms.
The upper structure (tower) of the crane is constructed of sheet steel in the shape of a box section. It contains the electric apparatus and the wiring, which need not be dismounted for transport. There is good ventilation through the funnel-type construction. The cranes can be supplied for a.c. or d.c.
To be read after Lesson 9.
INDUSTRIAL RADIO CONTROL APPLIED TO CRANES AND LIFTING GEAR
In the minds of most people the term "radio" covers the equipment for sending and receiving messages, signals, and, of course,, broadcasting. Only within recent years has radio equipment come to have a significant meaning as an aid to industry, and as a means to speed up production.
In mechanical handling equipment, the use of industrial radio control safeguards human material against many risks which must be faced in manufacturing processes today.
Industrial radio control falls into two headings:
(a) Speech transmission between a supervisor at a fixed trans-
10* 147 mitting station, and operators driving trucks, cranes or locomotives.
(b) Signal transmission between an operator equipped with a portable transmitter and an unattended crane, truck or trolley.
In order to determine the direction of hook travel, each carrier wave is modulated by one of two tone frequencies, between 100 and 1250 cycles, giving 6 tone frequencies in all.
The transmitter pack is designed to be worn comfortably by the crane operator at ground level. In order to achieve the maximum benefit of remote control he must be free to move about, to take up the best position for load control, and at times be able to walk outside the crane area and still have full control of the load being handled. He must be confident that if anything untoward happens he can stop the crane instantly, and that any failure of transmission or unexpected electrical interference will also bring the crane to a standstill.
The radio receiving unit mounted on the crane needs an a.c. supply at standard mains voltage. Where a crane is driven from d.c. supply, either a rotary transformer must be fitted with an output of approximately 1.5 kva, or an additional pair of conductors will be needed to feed the crane from a.c. source.
The transmitter may be readily modified to deal with cranes having both main and auxiliary hoists, and controls for operating grabs or magnets can be added, if required.
The application of radio equipment to dockside and wharf cranes is under consideration, where the best stand for the operator is alongside the hatches on a ship being loaded or unloaded.
To be read after Lesson 13.
CEMENT HANDLING PLANT
For many years cement was delivered firstly in jute bags, which had to be returned and kept in repair, and later in non-returnable paper sacks, but it was not always easy to dispose of them. The bags, which contained 2 cwt. of cement, had to be handled from barge, stacked in the warehouse.
It had been realized that the delivery of cement in bulk would provide economies in prime cost and time and would give great advantages of cleanliness in the areas concerned.
Delivering of cement in tippling wagons is a dusty process, and dangerous to the operative's health. It was known that cement, when aerated, would flow almost like water; pumping equipment was also available which would flow it for long distances.
The unloading plant consists of a counterbalanced bucket elevator suspended from a frame structure so that its height can be regulated to suit the variations in tide and draught. This elevator discharges into a screw conveyor fixed at one end and arranged to move in conjunction with the movements of the bucket elevator of the other. Cement then passes through a second fixed screw conveyor which delivers the cement to a surge hopper arranged over a cement pump. This pump, as well as the main control desk and the plant required for supplying barges with power and compressed air, is housed in a building adjacent to the unloader structure, and is arranged to discharge cement through a pipe-line made from asbestos-cement pressure pipes and electrically operated, remotely controlled valves to the machine silos. The control desk is arranged on the mimic diagram principle, so that the flow lines in use and the extent to which the silos are charged can be seen at a glance.
Fig. 13, Barge unloader at work. The part of the bulk cement handling plant
When required, the cement is automatically withdrawn from the base of the silos, conveyed to weighers and hatched into the process as required.
"3J• 'щиццн |»||мци mi и I.i тгадтиуо^.мшоячи
To be read after Lesson 14.
FLAT BELT CONVEYORS AND LOADERS
A typical lightweight vehicle-loading conveyor has a grip-face rubber belt and manual-hydraulic discharge height control. It is electrically driven and is available in a range of sizes and load capacities. Similar machines are also available with engine drives instead of electric motor drives and with fixed discharge heights or manually controlled adjustable discharge height mechanism.
Vehicle loaders of this type are ideal for the handling of bagged materials such as cement and flour, etc. Similar machines may have slat conveyors instead of flat belt conveyors. Sometimes doubt exists as to which type of machine is the most suitable for a specific unit load handling task. In such a case it may be as well to remember that flat belt conveyors are particularly useful where there is any risk of damaging the sacks or packages handled, e.g. where paper sacks are in use. For more robust work, chain and slat conveyors are generally employed.
To be read after Lesson 15.
Mobile conveyors include: (a) wheeled bag and package stacking conveyors, (b) conveyors and stackers for bulk materials, and (c) throwers for bulk materials.
The bag and package stacking conveyor is used for handling- bags. This machine is a mobile inclined belt conveyor. It is mounted on front wheels and rear castors and is driven by а3Д h.p. totally enclosed electric motor, through 30 ft. of trailing cable. The angle of elevation is varied by operation of a self-sustaining quick- screw lifting gear. A rubber-faced grip-face belt is employed. This enables bags and packages to be elevated up quite steep angles of inclination without damage.
This conveyor is useful for indoor duties and work out of doors, for warehouses stacking and for lorry loading and unloading. It can handle 1 cwt. or 2 cwt. bags as fast as they can be loaded.
The chain and rod variable height inclined package stacking conveyor is used in ports. This machine is electrically driven and is fitted with power-operated hydraulic elevated rams. It is shown at work, loaded with no fewer than eleven 280 lb. bags of sugar, and is 10 ft. long.
RUSSIAN-ENGLISH VOCABULARY
(to Exercises)
автоматизация automation автоматический automatic автопогрузчик fork lift truck аккумуляторнаябатарея storage battery
барабан drum
безопасность safety
береговой кран quaycrane
блок biock, pulley
блоки грузовых талей cargoblocks
боковая разгрузка sidedischarge
брашпиль windlass
бревна logs; short length cordwood
бульдозер bulldozer
вагонетка truck, runabout весы weighing device вилка fork ворот pulley вращение slewing всасывание suction
вылет, вынос (стрелы и т. п.)outreachвыполнять toperform
высокопроизводительный highly efficient, highly productive
высота (борта) depth
вытеснять to force out, to thrust out
гакигрузовые cargo hooks гибкийшланг flexible pipe гидравлическийпривод hydraulic drive гравитационныйспуск gravity lowerer грейфер grab
громоздкий cumbersome ['kAmbssam] грузоваяпетля sling, loop грузовик lorry, truck
грузовоеустройство cargo arrangement, cargo gear, cargo-handling equipment
грузоподъемныемашины mechanical handling equipment гусеничныйтрактор crawler tractor
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