Transport Equipment Part I - Conveyor Systems

What are Conveyors?

Definition: One that conveys, especially a mechanical apparatus that transports materials, packages, or items being assembled from one place to another. (Source)


Conveyors are used when:

1) Materials need to be moved frequently between specific points in the workplace,

2) Movement of materials take place in fixed paths/routes, &

3) There is a sufficient flow volume to justify the fixed conveyor investment.


They can be classified in different ways, some of which are:

1) Type of products handled - Unit load or Bulk load,

2) Location of the conveyor: Overhead, On-floor, or In-floor &

3) Whether or not loads can be loaded on to the conveyor


There are currently many industries making use of Conveyors, including: Food & Bakery, Paper Handling, Pharmaceutical/Medical, Health & Beauty, Automotives, Electronics, & Industrial & Consumer Products.

Companies in the above-mentioned industries can select from the myriad range of conveyors available in the market based on their specific requirements.

Let us now take a look at a few of the many different kinds of conveyor that are more widely used currently.
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1) Chute Conveyors

What's this? Used to link two powered conveyor lines, & convey items between floors.

Areas of Application - Provide accumulation in shipping areas, widely used for the transport of both coarse grain material (such as cereals, mineral ore and coal) and fine powders (as used in the chemical and pharmaceutical industries).

Advantage(s) - Economical; one of the most inexpensive methods of facilitating movement of materials

Disadvantage(s) - Difficult to control the items that being conveyed by the chutes; may result in packages shifting and turning so that jams and blockages could occur.

Video on Chute Conveyor here.

2) Roller Conveyor

a. Powered Roller Conveyor
What? These conveyors are belt or chain-driven, & runs on electricity solely.

Areas of Application - Accumulation of loads (heavy-duty) and merging/sorting of operations.

Advantage(s) - Does not depend on load weight of material, able to control movement of materials on the conveyor (for e.g. stop movement as and when one is required to by setting timing of conveyor).

Disadvantage(s) - Provides limited inclined movement capabilities.

Video on Powered Roller Conveyor here.


b. Gravity Roller Conveyor
What? An alternative to the Wheel Conveyor, movement of materials on this conveyor works on the rationale of gravitional force.

Areas of Application - For heavy-duty applications, and accumulation and sorting of operations.

Advantage(s) - Ablility to move objects without power (cost nothing to run), low capital costs and simple to install.

Disadvantage(s) - Gravity Roller Conveyors cannot convey materials that do not have fixed, solid forms (for e.g. loose powder), and they cannot convey upwards (only downwards due to gravity).

Video on Gravity Roller Conveyor here (with speech, requires Windows Media Player).


3) Vertical Lift Conveyor
What? Conveyor used to elevate or lower materials (in pallets, carton forms) from one level to another in a continuous high speed and high capacity operation. Can be hydraulic or mechanical.

Areas of Application - Additional production or distribution floor space is required, more aisle space for personnel and forklift traffic is required and when multiple floors are required to be tied together (so that there can be more space for production facilities).

Advantage(s) - Vertical Lift Conveyors are more economical than elevators. They can accommodate larger loads, both in size and weight.VRC’s have a smaller footprint then an incline conveyor, conserving valuable floor space.

Disadvantage(s) - Limited loading & unloading, as platform sizes and capacities may be limited due to the positioning of the load in relation to the guide structure.

Video on Vertical Lift Conveyor here.


More links to videos on Conveyors:
http://youtube.com/watch?v=d7fyVYXMIUM#
http://youtube.com/watch?v=7zycL3UI_fc
http://youtube.com/watch?v=E1L_SXlZLjQ
http://www.metacafe.com/watch/290944/choo_choo_train_sushi/

Transport Equipment Part II - Cranes

What are Cranes?

Cranes are lifting devices that are either stationary or mobile, and can lift materials above and beyond the capability of 2 workers. They can also be powered to increase their lifting abilities.

Note: Cranes provide more flexibility in movement than conveyors.

The major types of cranes include the following:

1) Jib crane

2) Bridge crane

3) Gantry crane

4) Stacker crane

Let us now go into details of 3 of the 4 different kinds of cranes.

1) Jib cranes

What? Jib cranes consist of a hoist-type lifting device mounted on a horizontal boom (jib).

Common configurations of the jib crane include:

(a) Pillar support - The jib is attached to a self-supporting floor mounted or floor-to-ceiling mounted mast

(b) Mast support - The jib is mounted on a mast which is supported on top and bottom supports and pivots.

(c) Bracket - The jib is attached to the wall or column by brackets.

(d) Walking - The jib is mounted on heavy undercarriages which may move back and forth on rails in the floor or floor and ceiling.

(e) Interlocking-A bracket crane designed to extend the travel of a monorail hoist by connecting the ends of adjacent jibs.

2) Gantry Crane

What? A gantry crane consists of a hoisting device that rides on a horizontal beam connected to legs with wheels attached to the bottom. Gantry cranes can be used either indoors or outdoors and can be pendant or radio controlled.

Variations are possible when one of the legs is replaced by a runway attached to the building or other fixed object. Gantry cranes are more often used outdoors because of the support legs.

3) Bridge Cranes

What? Bridge cranes are mounted on tracks that are located on opposite walls of the facility. The movement consists of horizontal travel along the length of the runway, horizontal movement across the width of the bridge, and vertical movement provided by the hoist.

Areas of Application - Bridge cranes are best used in low to medium volume activities for lifting large, heavy, or awkward items.

Advantage(s) - The advantages of bridge cranes include no interference with the work on the floor, reduced aisle space requirements, easy access to most areas within the lifting bay, and extension to areas outside the building.

Transport Equipment Part III - Industrial Trucks

What are Industrial Trucks?

Defintion: Industrial trucks are used to move materials over variable paths, with no restrictions on the area covered by the movement.

The major types of industrial trucks are:

1) Hand Trucks
2) Pallet Jacks
3) Walkie Stacker
4) Pallet Trucks
5) Platform Trucks
6) Counter-balanced lift trucks
7) Narrow Aisle Straddle trucks
8) Narrow Aisle Reach Truck
9) Turret Truck
10) Order Picker
11) Side-loader
12) Tractor Trailer
13) Personnel & Burden Carrier
14) Automatic Guided Vehicle (includes Tow AGV, Unit Load AGV, Assembly AGV, Light load AGV, & Fork AGV)

Today, we will be looking at details of the groups Pallet Jacks & Automatic Guided Vehicle (specifically Forklifts)


What is a Forklift Truck?

What? A forklift truck (a.k.a forklift and sideloader) is a powered industrial truck used to lift and transport materials, normally by means of inserting steel forks under the loads. Can be electrically powered or run on fuel.

Areas of Application - Most commonly used to move loads stored on pallets. Forklift trucks are available in many variations and load capacities. In a typical warehouse setting most forklifts used have load capacities of around one to five tons, though machines of over 50 tonnes capacity have been built and operated.

Pictures of diesel fueled internal combustion engine



Electric motor forklifts


Advantage(s) - (of LPG forklifts) Able to operate effectively 24/7 with no loss of power & life-time running costs can be lower than electric trucks, they can be used even in the most sensitive environments. Companies will not face battery disposal problems & there will be no harmful fumes under normal operating conditions.

Disadvantage(s) - Require sufficient aisle space to move around warehouse (or anywhere else relevant)


Pallet Jack

What? A tool used to lift and move pallets; the front wheels are mounted inside the end of the forks, and as the hydraulic jack is raised, the forks are separated vertically from the front wheels, forcing the load upward until it clears the floor. The pallet is only lifted enough to clear the floor for subsequent travel.

Manual Pallet Jacks


Powered pallet jack

Areas of Application - Powered pallet jacks are motorized to allow lifting and moving of heavier and stacked pallets. These generally contain a platform for the user to stand while hauling pallets around a warehouse or loading/unloading trucks. The powered pallet jack is generally moved by a throttle on the handle to move forward or in reverse and steered by swinging the handle in the intended direction.

Advantages - Mobile

Disadvantage(s) - Cannot move through narrow aisles, limited speed


Electronic Platform Trucks

What? Electric platform trucks are electric powered trucks with a large flat surface for holding objects to be transported. Some are also called warehouse utility vehicles, electric trolley carts, or powered platform truck vehicles.