Material Handling Equipment (MHE)

Material Handling Equipments

2008-01-13T23:10:00.000+08:00

What is Material Handling Equipments(MHE)?
Material Handling Equipments (MHE) are actually equipments that facilitate the handling of materials, which refers to the movement and storage of materials in the facility.

For better understanding, the video below shows the material handling equipment- Forklift trucks by Hyundai. Forklift truck is one of the many material handling equipments.

Importance of Material Handling :
Material handling is important as it is the key to warehouse productivity. When materials in the warehouse are being managed well, there will be an increase in efficiency and thus increase productivity. This is where MHE comes to place.

On the other hand, without MHE, it will eventually lead to poor material handling. Some of the poor material handling effects include confusion on product storage, too much walking, cluttered aisles, lack of standardisation, as well as high losses and damages.

Guidelines for Basic Handling

Standardise equipment by using equipment that can be deployed as many areas as possible.
Maximise continuous flow rather than intermittent or one-way flow.
Focus on handling rather than stationary
Minimise ratio of dead-weight to payload of handling equipment and not wasting unnecessary capacity of equipment.
Use gravity flow if possible rather than trigger on electricity.

As mentioned in the blog description that we will be focusing on MHE, we hope to create a better understanding for our readers regarding the different types of MHE. As there are many equipments, our group decided to classify them by their different uses so that the readers will have a clearer view.

As blogspot does not allow us to draw a tree map, this is the best we can show. The following shows the bullet form of the tree map for clearer view:

Transport Equipment:

- Conveyors
- Cranes
- Industrial Trucks

Positioning Equipment:

- Hoist
- Rotary Index Table
- Lift/ Tilt/ Table
- Balancer
- Ball Transfer Table
- Parts Feeder
- Air Film Device

Unit Load Formation Equipment:

- Pallets
- Inter-modal Containers
- Bins/ Basket/ Racks
- Cartons
- Bulk Load containers

Storage Equipment:

- Racks
- Automatic Storage/ Retrieval Systems (AS/RS)
- Stacking Frame
- Storage Carousel
- Mezzanine

Identification and Control Equipment:

- Bar- Coding
- Electronic Data Interchange (EDI)/ Internet
- Radio- Frequency Tag
- Magnetic Strip
- Machine Vision
- Portable Data Terminal

Transport Equipment (l) - Conveyors

2008-01-13T23:00:00.000+08:00

The first material handling equipment(MHE) we are going to touch on is Conveyors, which facilitates transportation in material handling.

What is conveyors?
By looking at the following video, I'm sure you will know what it is immediately.

Yes, the long black belt where you can see in most sushi restaurant, that carries plates and plates of sushi around the restaurant is an example of conveyor.

History of Conveyor:
Conveyor belts was used since 1901 and was invented by Sandvik and production of Steel Conveyor Belts started. It was being introduced by Henry Ford in 1913 as conveyor belt-based assembly-line in Ford Motor Company's factory production.

What are the characteristic of conveyors?

High throughput
Low power usage but high equipment cost
Manning required
Exclusive usage from other systems
For intermittent or continuous movement
Easy to control flows & fast response
Suitable for fixed routes
Can obstruct other flows & activities

Conveyor safety
When it comes to any electronic or mechanic devices, safety issues should be taken seriously:

Although this rule is common sense, people still disobey this rule and there are injuries and equipment damages every year.

There are technicians who are too confident in their ability without knowing power is connected and causing injuries.

Conveyors controls is more than just an on/off switches. Therefore, these control should never modified unnecessary reason. It is important to monitor the various controls making sure no one misused, modified, or disconnected them.

Others safety rules include:

There are actually many different types of conveyors like belt, overhead, screw, slat, roller, apron, chain, monorail, bucket etc. Now, i will focus on two types of conveyors which are widely used in the industry.

Belt Conveyors:

The video above on the sushi is an example of belt conveyors. Belt conveyors is a continuous moving belt that carries materials or packages from one place to another and consists of two pulleys. It can be used for light, medium and even heavy duty work.

Belt conveyors are the most commonly used bulk handling conveyors in history due to their reliability, versatility, and range of capacities. Materials from fine powders to large, lumpy stones can be handled on a belt conveyor.

Advantages of belt conveyor :

Lower labor cost than alternative means of transportation
Conveying a variety of materials
Wide range of capacities
Adaptability of path including terrain
Steep angle conveying
Flexible loading and discharging of materials
Reduced environmental impact, air and noise pollution
Lower energy costs than alternative means of transportation
Safety, thanks to minimal manual interfaces required
Reliability, that comes with the simplicity of fewer moving parts than other conveyor systems
Organize material work-flow
Reduce storage cart movement
Minimize operator fatigue

Disadvantages of Belt Conveyors:

Operate on incline only to about 28°
High initial cost
May need protection from weather
If the material is sticky, belt cleaning can be difficult and generally not very successful.

Overhead Conveyors:

Overhead conveyors provide continuous movement of materials overhead, as opposed to standard floor conveying systems. Overhead conveyors save space and are common for moving materials around an industrial facility. These conveyors are often used to sort, distribute, and buffer while maximizing space.

Types of Conveyors

The main types of overhead conveyors include automated electrified monorail (AEM) conveyors, enclosed track conveyors, and overhead chain conveyors.

Areas of Application for Overhead conveyors :

Overhead conveyors have many applications in manufacturing and distributing industries, such as in painting (electrostatic, dip and powder coating, spraying, etc.), parts cleaning, industrial ovens, transporting materials between facilities or workstations, and materials storage. Overhead conveyors provide a space-saving and economical solution for conveying needs.

Advantages of Overhead Conveyors :

The advantages of overhead conveyors is that it can help to maximise space as the overhead conveyor becomes a live store, which via vertical bends, can be routed into roof space, which would otherwise be non productive. Similar benefits could be at the production line when space for storage may also be at a premium. Other benefits may be the elimination of internal transport, such as fork truck or manually pushed trolleys.

Transport Equipment (ll) - Cranes

2008-01-13T22:50:00.000+08:00

The next handling equipment that facilitates transportation we are going to touch on is Cranes.

What is cranes?

In definition, Crane is a machine for hoisting and moving heavy objects by means of cables attached to a movable boom.

Jib crane, bridge crane, gantry cane, stacker crane are the different types of cranes available in the industry and they all have different uses. It is very important to understand the types of lifting systems available and how they differ from each other when deciding on what types of cranes to use.

Therefore we need to ask questions like:

What am I actually doing with the system? For example, will it be used to move expensive tools into/out of a molding machine or to load/unload steel from trucks?

How can a crane increase the safety of the loads being lifted?

How can a crane improve my workers' safety in handling the loads?

How frequently will it be used each shift?

How will the load need to be moved and located?
How easy is it to move the system to a new location in my factory?

Do I really need three axes of hook movement (e.g., up/down, left/right, and forward/back) or will only two be sufficient?

How heavy are the loads to be lifted?

How much money should I invest in a system?

Crane Safety

Construction crane safety is also a very important issue to take into consideration. The Division of Occupational Safety and Health (DOSH) held a share holder meetings on October 29th through November 5th to gather feedback on the Construction Crane Certification and Operator Qualifications and Experience drafts.

The following article is on new crane safety law in US:

Last updated October 19, 2007 9:33 p.m. PT
L&I looks to public on new crane safety law
Comments can help agency work out the detail
By ANDREA JAMESP-I REPORTER

A tough new law passed earlier this year is designed to give some peace of mind to people who live and work near the looming construction tower cranes dotting Western Washington's skylines.

But the specifics -- just how the safety law will be carried out -- are still being written by the state Department of Labor and Industries.

By the end of this month, L&I plans to have completed its first draft of the rule, spokeswoman Elaine Fischer said. The department will gather comments on the draft in a series of meetings statewide from Oct. 29 through Nov. 5.

The construction industry already voiced its concerns and opinions in a round of meetings in July.

"The biggest issue for discussion was probably the number of operator hours that should be required for operator certification on different types of cranes," Fischer said.

To be considered qualified, according to the law, a crane operator must have up to 2,000 hours of experience -- a maximum that has been challenged by many in the industry as unworkable.

Legislators enacted the law in the wake of several alarming crane incidents late last year. After a 210-foot-high crane collapsed in downtown Bellevue, killing a man in his nearby apartment and severely damaging three buildings, structural problems were found in several more cranes operating in the Seattle area.

A six-month L&I investigation found that the collapsed crane's steel base was to blame. Tower cranes, which are used for construction on skyscrapers, are normally installed in concrete. The Seattle engineering firm that designed the foundation, Magnusson Klemencic Associates, was fined $5,600.

Lease Crutcher Lewis, the general contractor at the Tower 333 site, where the crane fell, was fined $9,200. Both firms are named in a lawsuit filed by the family of the deceased.
Under the new law, which takes effect Jan. 1, 2010, the state will play a much bigger role in ensuring that tower cranes are being operated properly and are secure in their foundations. Under the old rules -- criticized for being lax -- responsibility for safety fell mostly to construction companies.

In the upcoming meetings, L&I will take suggestions in two areas: how crane inspectors should be certified, and what qualifications should be needed to become a crane operator.

"There's a lot of different kinds of cranes and a lot of people that want to weigh in on that," Fischer said. "We're starting from scratch here in our state developing rules in this industry. We have to involve people in the industry that know how things operate."

Developers will have to contract with a certified crane inspector to certify their cranes. That means that the cranes, its inspectors and its operators must all be certified.

The crane inspector rule will likely operate similar to sister rules regarding amusement ride inspectors and maritime crane inspectors, she said.

The law also requires that an independent professional engineer stamp approval on any "non-standard" tower crane base.

P-I reporter Andrea James can be reached at 206-448-8124 or andreajames@seattlepi.com.

Therefore, we can see that general safety rules is also taken into serious considerations. Some of the rules operators shall comply when operating cranes and even hoist are:

Do not engage in any practice that will divert your attention while operating the crane.
Respond to signals only from the person who is directing the lift, or any appointed signal person. Obey a stop signal at all times, no matter who gives it.
Do not move a load over people. People shall not be placed in jeopardy by being under a suspended load. Also, do not work under a suspended load unless the load is supported by blocks, jacks, or a solid footing that will safely support the entire weight. Have a crane or hoist operator remain at the controls or lock open and tag the main electrical disconnect switch.
Ensure that the rated load capacity of a crane's bridge, individual hoist, or any sling or fitting is not exceeded. Know the weight of the object being lifted or use a dynamometer or load cell to determine the weight.
Check that all controls are in the OFF position before closing the main-line disconnect switch.
If spring-loaded reels are provided to lift pendants clear off the work area, ease the pendant up into the stop to prevent damaging the wire.
Avoid side pulls. These can cause the hoist rope to slip out of the drum groove, damaging the rope or destabilizing the crane.
To prevent shock loading, avoid sudden stops or starts. Shock loading can occur when a suspended load is accelerated or decelerated, and can overload the crane or hoist. When completing an upward or downward motion, ease the load slowly to a stop.

Jib crane, Bridge crane, Gantry crane, Stacker crane are some of the different types of crane available.

Jib Cranes

Jib crane is a crane having an arm guyed at a fixed angle to the head of a rotating mast and it consists of a pivoting head and boom assembly which carries a hoist and trolley unit. The pivoting head is supported either by a floor-mounted mast providing 360 degree boom rotation or by an existing building column which provides 180 degrees of boom rotation.

Advantages of Jib cranes :

The advantage is the strength, stability and flexibility of the device. It is ideal for lifting a product to or from one material handling system to a work station or machine. It should be a repetitive process.

Another advantage is that jib crane is commonly used for workstation and simple loading / unloading operations where it is not necessary to spot a load precisely. Also, Jib cranes most often handle lighter loads at lower duty cycles than their bridge and gantry crane counterparts.

Disadvantages of Jib crane :

The major disadvantage is that it is stationary and cannot be moved easily from one work area to another. It is designed for positioning a work piece or tool, rather than for moving a product along in the work flow like an overhead crane.

It is also unsuitable to use when there is a need for precise locating of heavy loads, a large area of hook coverage, or frequent use for heavy loads. Another disadvantage is that the hook coverage is limited to the boom length (typically a maximum of 20 ft). The hook operates along a boom which rotates about a fixed point.

Bridge Crane

A bridge crane runs on an elevated runway system along the length of a factory and provides three axis of hook motion (X, Y, and Z). The hoist moves the load up and down, the trolley moves the load right and left, and the bridge of the crane moves the load forward and backward. Both single and double girder overhead traveling bridge crane designs allow very precise hook positioning and gentle load placement.

Advantages of bridge crane :

greatest flexibility for hook coverage and control over the load fewest number of physical obstructions on your factory floor
no interference with the work on the floor
reduced aisle space requirements, easy access to most areas within the lifting bay
extension to areas outside the building.

Disadvantages of bridge crane :

Problems encountered like:

Crane travelling too far before stopping.

It is likely that it uses electric motor brakes and that, like most cranes, the brake pads haven't been replaced (they require replacing or adjusting every 3 months).

Bearings wearing out too soon.
Contactor problems.
Broken push button pendant or cable.
Parts availability problems.
Brakes wearing out or not working properly.

Please enjoy the following video from North American Industries

http://www.naicranes.com/gallery/vidgallery.htm

Positioning equipment (l) - Hoist

2008-01-13T22:40:00.000+08:00

The first positioning equipment we are going to touch on is hoist.

What is hoist?

A hoist is a device used for lifting or lowering a load by means of a drum or lift-wheel around which rope or chain wraps. It may be manually operated, electrically or pneumatically driven and may use chain, fiber or wire rope as its lifting medium.

Advantages of hoist

It can be placed in tight spaces such as between benches
Flexible

Disadvantage of hoist

There is a need take the weight usage into consideration. For example, package hoist is most suitable for light to moderate usage. When handling with heavy usage, we must use built-up hoist. (It will be covered in later part of this post) There is also a need to minimise ratio of dead-weight to payload of the handling equipment.

It usually consists of a block and tackle—a combination of one or more fixed pulleys, a moving pulley with a hook or other similar means of attaching loads, and a rope (or cable) between them.

Characteristic of hoist

The basic hoist has two important characteristics to define it: Lifting medium and power type.

The lifting medium is either wire rope, wrapped around a drum, or load-chain, raised by a pulley with a special profile to engage the chain. Both the wire rope hoist and chain hoist have been in common use since the 1800s.
The power type can be either electric motor or air motor.

It must be noted that a hoist can be built as one integral-package unit, designed for cost-effective purchasing and moderate use, or it can be built as a built-up custom unit, designed for durability and performance.

Package Hoist:
The term “package” refers to the fact that the hoist is an “integrated package”. In other words, the hoist is made up of a series of “proprietary” parts, designed specifically for the purpose of that hoist and all electric chain hoist and most wire rope hoists are “package type” hoists.

Therefore, package hoist is most suitable for light to moderate usage, standard speed and normal lifting lengths. If any service that does not have the norms listed, there would be increase in down time, higher maintenance cost and a drastically reduced service life. The farther out of the norms, the worse the performance. Package hoist is normally being used is in a machine shop or fabricating shop.

Built- up Hoist:

When the needs exceed the norms listed above (package hoist), it would be most suitable to use a built- up hoist. It should be noted that built up hoists can be as low as 3 ton capacity, when special speeds, duty cycles or long lifts are required, but normally heavy usage applications, high production, maintenance intensive applications. Even though built-up hoist is more expensive, it is easier to repair and more durable. Built-up hoist on the other hand is used for heavy to sever service like Steel Mill or NASA due to its durability, performance, and reparability requirements.

Hoist Safety

Only qualified and licensed individual can operate both cranes and hoists, and there is a list of safety rules and responsibilities whereby all personnel which came in contact with the equipment must obey to maintain a safe workplace for all personnel.

The following PDF file shows a list of safety rules when handling hoist:www.state.ar.us/labor/pdf/program_crane_safety.pdf

Types of hoist

When deciding which type of hoist should be used, so as to provide extended service and efficiently matches the requirements of the job; we should also ask questions like:

Is a manual or power hoist needed?
Is power hoist which is an electric or pneumatic (compressed air) type the better choice?
What load capacity is required?
How fast and how high must the hoist work?
Is a chain or wire rope required?
What headroom is available for hanging the hoist?
Manual or Power?

Construction hoist:
Although there are many types of hoist, construction hoist is what most of us haven seen before as it is part of our daily life.

It known as a Man-Lift, or construction elevator, this type of hoist is commonly used on large scale construction projects, such as high-rise buildings or major hospitals.

The purpose being is to carry personnel and materials quickly between the ground and higher floors, or between upper floors.

The construction hoist is made up of either one or two metallic cages which travel vertically along stacked mast tower sections. For controlled travel along the mast sections, most modern construction hoists utilize a motorized rack-and-pinion system mounted onto the mast sections, while some older hoists still utilize a system of counterweights.

Positioning Equipment (ll) - Rotary Index Table

2008-01-13T22:30:00.000+08:00

The next positioning equipment is Rotary Index Table.

What is Rotary Index Table?
Rotary Index Table is a precision work positioning device used in metalworking. It enables the operator to drill or cut work at exact intervals around a fixed (usually horizontal or vertical) axis. Some rotary tables allow the use of index plates for indexing operations, and some can also be fitted with dividing plates that enable regular work positioning at divisions for which indexing plates are not available.

Examples of how it can be used:

Machine spanner flats on a bolt

Drill equidistant holes on a circular flange

Cut a round piece with a protruding tang

Cut complex curves (with proper setup)

Rotary tables are made with a solid base, which has provision for clamping onto another table or fixture. The actual table is a precision-machined disc to which the work piece is clamped (T slots are generally provided for this purpose). This disc can rotate freely, for indexing, or under the control of a worm (handwheel), with the worm wheel portion being made part of the actual table.

Rotary indexing tables have either fixed or adjustable indexing angles. During each revolution, the table stops for a specified period of time so that an operation can be performed at each station. The bearings that support rotary indexing tables determine both the load capacity and accuracy.

Criteria in selecting rotary index table:

Selecting rotary indexing tables requires an analysis of specifications and features. Specifications include maximum indexing increment, work table diameter, maximum axial load, and maximum radial load.

Rotary indexing tables are powered by pneumatic and electric motors, hydraulic drives, and manual actuation.

Pneumatic rotary indexing tables are suitable for small and medium loads. They are powered by one of more pneumatic cylinders, each of which represents an index. During the return stroke, a pawl locks the table in place. With some devices, the pawl can be adjusted to change the number of indexes.

Electrically-powered tables are generally faster than pneumatic devices and can handle heavier loads.

Tables that are powered by hydraulic drives use a pressurized fluid that transfers rotational kinetic energy.

Manually-actuated rotary indexing tables often include a hand crank or are loosened, turned, and adjusted by hand.

Rotary Index Table Safety

Like wise, the safety of rotary index table is also as important as any other equipment.

In a rotary index table, the parts are loaded well away from the point of operation.
The operator’s hands are kept a safe distance from the riveting area.
The rate of production depends on the time required to load the parts.
Normal cycle time is the time required to load component parts plus approximately 5 second for indexing.
Riveting is done during the loading process.
Preventative maintenance are also established and maintained to reduce downtime for repairs and replacement of parts. It is important to take note that when doing preventive maintenance, make sure that the electrical power and air supply to the machine are OFF! :

Cleaning :
Prior to operation, or on a daily basis, perform the following procedure:
1. Using a clean, dry cloth, wipe the machine to remove accumulated dust or other contamination.
2. Using a solvent or similar cleaning fluid, remove accumulated oil or grease from areas not requiring lubrication.
3. Using an approved–type air hose, blow out any chips or metal particles that may be in the working area.

Inspection :
1. Inspect the entire machine for evidence of loose or broken parts. Repair or replace as necessary.
2. Inspect all moving parts for excessive wear. Replace worn parts if required.
3. Inspect all air lines and connections for excessive leakage. Repair or replace as required.
4. Inspect all electrical wiring for loose connections or cracked or worn insulation. Repair or replace if required.

Lubrication :
The Rotary Index Table is equipped with grease fitting under the machine base. Access to the fitting is gained by removing the top of the plastic guard, then using a grease gun with a hose and fitting.
Lubricate the machine with Mobil HP Lithium 12 grease (or equivalent) every 20,000 rotations. Use the same grease to lubricate the drive screw on any optional moving insertion heads.

Moisture and Scrap Removal :
Periodically check the moisture separators at the air supply inlet area of the machine, and drain if necessary.

Also check the scrap containers. During normal operation of the machine, the scrap from the terminal strip is placed in the container on the side of the machine, and scrap from the housing (wire and nib) is placed in the container located at the back of the machine.

Ways to remove scrap from container: To remove the scrap from the container, carefully unscrew the container; remove the cylindrical screen from the inside of the container, and dispose of the scrap in an appropriate manner. Replace the cylindrical screen in the container and replace the container before resuming production.

Unit Load Formation Equipment (l) - Pallets

2008-01-13T22:20:00.001+08:00

A pallet is a low, portable platform constructed of wood, metal, or fiberboard, built to specified dimensions, on which supplies are loaded, transported, or stored in units. Pallets are the most common form of unitizing device.
Some of the primary pallet material choices are wood pallet (most common), steel pallet, paper pallet, metal pallet, plastic pallet.

Pallets may afford two- or four-way entry. The two-way entry pallet is so constructed that the forks of a forklift truck may be inserted from either the front or rear of the pallets. The four-way pallet is so constructed that the forks of a forklift truck may be inserted from any of the four sides.
Various types of pallets are two-way double wing, two-way flush, two-way reversible flush, two-way single wing, four way nonreversible flush, block type, foam padded plywood pallet, single face pallet.

Advantages of using pallets:

Handles more items at a time
Reduces the number of trips
Reduces the handling costs
Reduces the loading and unloading times
Reduces the product damage

Disadvantages of using pallets:
Operators can’t use either option in areas with rocks or other firm high spots. You may need a forklift to install and remove pallets.

Different types of pallet material will have its own pros and cons.

The majority of pallets are made from wood.

Advantages:

Lower cost than most other materials
Can be repaired/renovated
Can be painted and easily printed on
Stickers can be easily removed
Their popularity allows them to be used universally

Disadvantages:

The dimensions can vary slightly
Can be distorted through rough handling
Contain metal parts (nails) which could interfere with metal detection (some now are made without nails)
Need to be maintained
Can become contaminated with unwanted bacteria or pests. Export pallets need to be heat treated.
Weight can fluctuate due to wood variations and level of absorbed moisture
They can be prone to splintering or have loose nails
Wooden pallets are not fully washable
They cannot be nested in each other when empty

Plastic

Advantages:

Precise and consistent specifications
Do not absorb humidity
Some can be moulded so that that can be nested when empty
No sharp edges, loose nails or splinters
Can be cleaned effectively
Very low maintenance required
Can be manufactured from recovered material
Can be lightweight (depending on density)
Long life if handled correctly
Washable and not prone to infection or infestation

Disadvantages:

High purchase cost
Cannot be repainted
Stickers may not be easily removed, leaving bug harbouring and unsightly residue
There are no universal standards, reducing the possibility of pooling and swapping

Metal

Advantages:

No loose splinter/nails
Long life if handled correctly - can withstand rough treatment
High load bearing capacity (depending on specification)
Washable and not prone to infection or infestation
Low maintenance requirement

Disadvantages:

Can be warped through mis-use
Heavy
Stickers may not be easily removed, leaving bug harbouring and unsightly residue
Very high purchase cost
There are no universal standards, reducing the possibility of pooling and swapping

Paper

Advantages:

Lighter weight
Disposable
Recyclable
Very flexible to adapt to special transport needs
Meet IPPC requirements
Meet international regulations on trade (ISPM)
No fumigation
Environmental Friendly
Clean and dust free

Disadvantages:

Susceptible to moisture
Lack stiffness compared to most other pallet materials

Unit Load Formation Equipment (ll) - Inter-modal Container

2008-01-13T22:10:00.002+08:00

Since the 1960s major efforts have been made to integrate separate transport systems through intermodalism, which took place are several stages. This involves the use of at least two different modes in a trip from origin to destination through an inter-modal transport chain. Inter-modal transportation is the movements of passengers or freight from one mode of transport to another, commonly taking place at a terminal specifically designed for such a purpose.

The container is a large standard size metal box into which cargo is packed for shipment aboard specially configured oceangoing vessels and designed to be moved with common handling equipment enabling high-speed inter-modal transfers in economically large units between ships, railcars, truck chassis, and barges using a minimum of labor. The container, therefore, serves as the load unit rather than the cargo contained therein, making it the foremost expression of inter-modal transportation.

Advantages:

Flexibility of usage. It can transport a wide variety of goods ranging from raw materials (coal, wheat), manufactured goods, and cars to frozen products.
Costs. Relatively to bulk, container transportation reduces transport costs considerably, about 20 times less than bulk transport.
More items can be handled at the same time, thereby reducing the number of trips required and, potentially, reducing handling costs, loading and unloading times, and product damage.
Enables the use of standardized material handling equipment.

Disadvantages:

Time spent forming and breaking down the unit load.
Cost of containers/pallets and other load restraining materials used in the unit load.
Empty containers /pallets may need to be returned to their point of origin.

The article below will illustrate real world application of inter-modal transportation:

Containers from around the world can be found at Diamond Express Inc., a trucking company tucked away between First Avenue North and the airport.
"We're the largest inland container depot around the Birmingham area," says veteran trucking executive Tom Brown, owner of Diamond Express.

The company has developed a niche doing what used to be called "piggybacking," delivering truck trailers to and from flatbed railcars. The process is more modern these days, with containers lifted off trailer chassis and loaded, two-high, minus their cumbersome wheels.

Diamond Express, with $8 million in sales revenue last year, transports and stores containers from around the globe. One of its top customers is Maersk-Sealand, the world's largest steamship company. Intermodal freight, mostly containers from the Far East coming through ports in California, includes clothing, lumber, paper and electronics.

But Brown says his company, spread across three lots totaling 15 acres, doesn't rely solely on international export/imports to and from companies in the South, or the rail-dependent intermodal business as a whole.

"With Norfolk Southern closing its Birmingham intermodal ramp, and Burlington Northern (Santa Fe) moving its California freight through Atlanta (instead of Birmingham), we started focusing four or five years ago on van freight in the South," he says. Industries served include paper products, cooking oil containers and fire extinguisher equipment, to name a few. Local clients include Pepsi bottler and snack food vendor Buffalo Rock, Stevens Graphics, Amerex, Cook Publications and Ventura Foods.

Brown says the ratio of intermodal containers to van freight business is 60/40.

"The main advantage of intermodal is transit time and rates," he says. "If you can put a container that's not time-sensitive on rail service that gets to California in four or five days, and for cheaper rates (than trucks), then you stay with it."

Diamond uses 65 leased owner-operator trucks and 25 company-owned trucks. About 20 office personnel are employed in the company's Birmingham headquarters, and at terminals in Atlanta and Chattanooga.

Hauling the phone books
One of the company's biggest jobs is delivering BellSouth phone books in nine Southern states. Last year, Diamond Express was rated the best delivery company by supervisors at 514 drop-off sites, scoring a 3.85 out of 4.0 (similar to a college grading scale) in quality of service, professionalism, courtesy, condition of the books, on-time performance and other criteria.

Below are some pictures that illustrate inter-modal containers.

Storage Equipment (I) - Pallet Racking

2008-01-13T22:00:00.000+08:00

Basically, racking is one of the equipments that contributes to the storage system of the distribution centre, ensuring it to be well-designed by making use of the volume available, providing proper access to the stored goods through facilitating the throughput of goods as well as minimizing the distance traveled. Furthermore, the use of this equipment will also minimize the risk of insecurities towards damage and deterioration of goods.

There are several choices of racking medium depending on the physical characteristics; risks of hazard, deterioration and hazard; values of the goods. Furthermore, the capital availability of users, characteristics of the available storage methods and equipment as well as the stock and throughput levels must be taken into consideration.

Below are elaborations of several types of racking used by most warehouses and distribution centres throughout the world.

Selective Pallet Racking
This pallet racking is most generally used. This is due to it easy access to every load and flexible choice providing 100% selectivity to every load. This equipment is mainly for the best access and high-demand product. Although it delivers maximum access to stored pallets, it requires numerous aisles and aisle space, resulting in lower storage density than other form of racking.

A type of a selective pallet racking is the boltless selective pallet, which in-demand due to its tool-free assembly, fast and affordable price. However, initial savings can be offset by high replacement and maintenance costs as it is found that the open-back roll formed columns don’t withstand the impacts of fork truck.

Drive-through Pallet Racking
This type of pallet racking is used for storing pallets of a similar stock-keeping unit (SKU) or goods. In this racking, loads are supported by rails attached to vertical frames, and lift trucks are driven between the frames to enter the rack from either side to pick up or pull out pallets as pallets can slide backwards on a continuous rail, open at both ends, which thus, allowing ‘first-in, first-out’ storage.

Drive-through pallet racking is used when there are seasonal items moving quickly out of the inventory and when there are large amount of similar items that can be stored in a single pallet position. It is not encouraged using this equipment when storing a wide variety of loads in the rack. Although selectivity is forgone, storage density is improved due to the ability to store a large amount of similar loads in a smaller area.

Push-back Pallet Racking
The objective of the push-back pallet racking is to minimize empty pick faces or honeycombing. The ideal appliance of the racking will be where all loads in a row are alike and not critically in a ‘first-in, first-out’ stock rotation.

This racking has the same storage density as the drive-through racks and up to 90% more product storage than selective pallet racking systems, but with greater selectivity of 4 times more than the drive-in pallet racking. Due to these factors, it improves the speed of pick rates. Besides offering a large target for loading and unloading, it also maximizes space through storing a range of SKUs on different levels of lanes for convenient access of goods.

Here’s how it operates:

Loads in each row lie on a cart by forklift on an inclined rail sloping gently toward the front. When a new load is deposited into a lane, it ‘pushes back’ the loads already at the face and those behind. When the load is picked, the forklift takes out the front pallet, allowing the pallets on carts behind it to roll gently to the front of the rack, showing a "push back" momentum. The nested carts of the racking make position and retrieval of loads convenient.

Storage Equipment (II) - Automated Storage and Retrieval Systems (AS/RS)

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AS/RS is an array of computerized routines for automatically receiving and shipping materials from defined storage locations without manual labor, generally used in distribution centers and warehouses all over the world. It generally include machines moving up and down one or multiple parallel storage aisles, receiving and shipping products and materials for distribution to internal and external locations.

It's advantages:

Grant users with increased tracking and inventory control, plus greater flexibility having room for changing business conditions.
Specialized construction and installation systems, providing seismic and rack supported buildings.
Feed-in and feed-out systems, very high tolerance racking, automatic fire protection strictly controlled weight checking and load sizing.
Systems comprising modular subsystems easily substituted reducing downtime and expanding the life of the whole system.
Produces key reserves in inventory storage costs, as greatly improved both vertically and horizontally warehouse space utilization creating larger storage density.
Reduces labor costs, lowering essential labor force necessities, improving workplace safety, and eliminating staff from complex operational conditions.

However, there are the disadvantages of it as well;

Requires significant investments of a company's capital; Particularly for maintenance and updating of different subsystems. Also, capital expenses can tempt some business owners to cut financial corners, buying "bargain" systems that are ill-equipped for extensive, long-term use à end up costing far more in the long run
Not without occasional frustrations for maintaining highly integrated systems; Requires knowledge, skills and experience.

However, interrupted AS/RS service extends from the measurable such as lost in manufacture and delivery revenue, increased labor costs for repair, to the intangible such as the shrinking workforce confidence in the company's operations as well as the client’ confidence.

Identification and Control Equipment (I) - Bar Code

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Series of vertical bars and spaces representing numbers and other symbols; it is affixed to postal mail, retail store items and identification cards in order to identify a particular location, person or product number. The symbol usually consists of five parts: a quiet zone, a start character, data characters which include an optional check character, a stop character, and another quiet zone. Although there is no particular standard bar code, there are several different bar code standards (symbologies) serving different industries, geographic needs or uses. The most common bar code standards are; Code 39 (Code 3 of 9), serving in Identification, inventory, and tracking shipments; Interleaved 2 of 5, serving the shipping and warehouse industries; and Uniform Product Code (UPC) serving the Retail stores in sales checkout, inventory and such.

History traces back to its first patent for a bar code type product (US Patent #2,612,994), which was issued to inventors Joseph Woodland and Bernard Silver on October 7, 1952. This bar code was made up of a series of concentric circles described as a "bull's eye" symbol, and over time, has converted into today’s UPC bar code.

Bar code consists of information, called barcode data, or also point-of-sale (POS) data. It is automatically gathered as a consumer's purchases and place through a check-out. Massive volumes of such data is gathered every day by the POS terminals and processed before being very useful for marketing purposes, such as planning on pricing a particular product, or initiation of sales campaigns.

Barcode Reader

Bar code is read by a barcode reader, which is a stationary or hand-held input gadget used in capturing and reading information contained in it. Also called a price scanner or POS scanner, a barcode reader uses a laser beam sensitive to the reflections from the line and space thickness and variation before translating the reflected light into digital data transferred to a computer for immediate action or storage. A barcode reader consists of a scanner, a built-in or external decoder and a cable which is used to connect the reader with a computer.

Consisting of five basic types, the simplest barcode reader is the pen wand, which contains no moving parts. It is known for its durability and low cost. On the other hand, it can be challenging to the user, as it has to stay in direct contact with the bar code, held at a certain angle, and moved over the bar code at a certain speed.

Another type is the slot scanner which remains stationary when the item with the bar code on it is pulled by hand through the slot. It is normally used to scan bar codes on identification cards.

Also, there is the type of bar code reader, the CCD scanner, having a better read-range than the pen wand and is often used in retail stores. Normally, a CCD scanner has a "pistol" type interface and has to be held at most 2.5cm from the bar code. Although several readings are taken to reduce the possibility of errors every time the bar code is scanned, it cannot translate a bar code that is wider than its input face.

Furthermore, there is another type called the camera reader, or image scanner. It uses a small video camera capturing an image of the bar code before using sophisticated digital image processing techniques to translate the bar code. The camera reader can read a bar code from about 7.5cm to 23cm away and commonly costs less than a laser scanner.

Lastly, a laser scanner, either stationary or hand-held, does not have to be close to the bar code to do translate it. Regardless of orientation, it uses a system of mirrors and lenses allowing the scanner to translate the bar code, and can easily translate a bar code up to 61cm away. A laser scanning may perform up to 500 scans per second to reduce the possibility of errors. A specialized long-range laser scanner is capable of reading a bar code up to 0.9m away.

Identification & Control Equipment (ll) - Electronic Data Interchange

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EDI stands for Electronic Data Interchange. It is the application to application transfer of business documents between computers. The transfer of files requires that the sender and receiver agree upon a standard document format for the document that is to be transmitted.

EDI is a new way of doing business. Many businesses are looking to EDI as a new, fast, inexpensive, and safe method of sending purchase orders, invoices, shipping notices, receiving advices, and other frequently used business documents. For example, Auto manufacturers use EDI to transmit large, complex engineering designs. Multinational firms use EDI to communicate between locations. And universities use EDI to exchange transcripts quickly.

EDI can also be used to transmit financial information and payment in electronic form. When used in this application, EDI is usually referred to as Financial EDI or Electronic Funds Transfer (EFT).

The Operation of EDI
EDI starts with a trading agreement between you and your trading partner. You make joint decisions about the standard to be used, the information to be exchanged, how the information is to be sent, and when information will be sent. The information can be sent through a direct connection (Point-to-Point), or through a VAN.

To send a document, you use your EDI translation software to convert the document format into the agreed upon standard. The translator creates and wraps the document in an electronic envelope and puts the ID for your trading partner on it.

If the information is to be sent Point-to-Point, the communications software sends the document directly from your computer system to your partners computer system. If a VAN is used, the communications software dials the phone number for the network and transmits the envelope containing the document. The VAN reads the ID on the envelope and places it in the correct mailbox.

Your trading partner's modem calls the network and retrieves everything in the mailbox. The EDI translator opens the envelope and translates the data from the standard form to their application's format.

If you attempt to do EDI without translation, you run a great risk of transmitting data that your trading partner will not be able to read. Your trading partners may use business applications on computers that are different than yours. The translator ensures that the data you send is converted into a format that your trading partner can use.

EDI Standards
EDI consists of specific data interchange methods agreed upon by standards bodies. EDI messaging protocols help ensure that data arrive as expected, and that corrupted or incorrect data are automatically detected and reported.

Advantages:

Save Money
The cost of paper and paper processing is incredibly high compared to a properly implemented EDI program. RJR Nabisco estimates that processing a paper purchase order costs the company $70. Processing an EDI purchase order reduces the cost to a mere 93 cents.
End Repetition
If your trading partner wants a copy of a document, instead of calling you they simply check their mailbox. This results in a great time savings from not having to copy and fax/mail copies of business documents.
Save Time
EDI also saves time over paper processing since the transfer of information from computer to computer is automatic. There is no need to re key information with EDI. And the chance for error drops to near zero, with no data entry.
Reduced Inventory Costs
The Automotive Industry effectively implemented Just-In-Time (JIT) inventory concepts with their suppliers through the use of EDI. Through this JIT method a company keeps minimal inventory on hand and continually re-orders and replenishes -- sometime several times a day -- directly from the supplier. The order and order status are exchanged between trading partners through EDI. The implementation of JIT can greatly decrease an organization's cost of maintaining inventory stock by reducing (1) warehouse-floor-space cost, (2) warehouse-personnel cost and (3) the cost of maintaining idle inventory.
Improve Customer Service
The quick transfer of business documents and marked decrease in errors allow you to do business faster and more efficient. KMart is an example of a retailer that implements a Vendor Stock Replenishment (VSR) program. With VSR, the KMart warehouse sends stock as their EDI system reports it and automatically bills the client. It can cut weeks from the order fulfillment cycle and ensures that product is always on the shelf.
Expand Your Customer Base
Thus with improved customer service, you can ultimately expand your customer base. Many large manufacturers and retailers are ordering their suppliers to institute an EDI program. So, when evaluating a new product to carry or a new supplier to use, the ability to do EDI is a big plus.

General Benefits
Many industries have improved relationships with customers and suppliers during the EDI implementation process.

Many companies re-engineer and reorganize supporting administrative processes, departments, and functions to take advantage of EDI. The re-engineering often significantly reduces personnel and administrative costs.

A major effort is being made in the retail industry to collect and analyze point-of-sale data to project customer needs, wants, and buying habits. If Quick Response in the retail industry is any indicator, having the right product at the right place at the right time will significantly increase sales volume and profit for a company.

Disadvantages:

Too Many Standards
There are too many standards bodies developing standard documents formats for EDI. For example your company may be following the X12 standard format, while your trading partner follows the EDIFACT standard format.
Changing Standards
Each year, most standards bodies publish revisions to the standards. This poses a problem to EDI users. You may be using one version of the standard while your trading partners are still using older versions.
EDI is Too Expensive
Some companies are only doing business with others who use EDI. If a company wants to do business with these organizations, they have to implement an EDI program. This expense may be very costly for small companies.
Limit Your Trading Partners
Some large companies tend to stop doing business with companies who don't comply with EDI. For example Wal Mart is only doing business with other companies that use EDI. The result of this is a limited group of people you can do business with.

Electronic Data Interchange Diagram

An Executive Briefing on EDI

Company-A reconciles the invoice with the internal system, and transfers the payment information to the EDI software mapping routines.
Company-A's EDI software converts the payment information into a Payment Order / Remittance Advice X12 data stream and transmits to its bank by way of the VAN.
The EDI software logs to whom and when the X12 transaction was sent. If it does not receive a functional acknowledgment within a predetermined amount of time, it will notify the EDI software operator that there may be a problem with the transmission.
Company-A's bank receives the Payment Order / Remittance Advice from Company-A and issues an Electronic Funds Transfer to Company-B's bank.
The invoice has been submitted and paid entirely electronically.

*Note*
X12 Standards
X12 is the inter-industry EDI standard in the United States of America.

Value Added Networks
VANs are large networks, usually international in nature, which transport EDI information among participating trading partners. VANs offer services such as EDI packet transportation, conversion between different EDI versions and standards, audit trails, security, trading partner identification, education, and consulting. VANs can greatly facilitate a company's entrance into the EDI arena.

Problem Scenario

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We will take Company ABC as an example. Company ABC has a warehouse that supports high-end retail products (mostly formal wear). It wants to implement transport equipment in its warehouse to enable better movement of products through fixed routes during sortation. Now, Company ABC is fretting over whether to use overhead conveyors or belt conveyors for their warehouse.

Solutions:
The answer is quite obvious actually. From the information for the two types of conveyors given in this blog, it could be seen that overhead conveyors is more suitable.
It saves space and doesn’t obstruct movement of personnel and other equipment as it provide continuous movement of materials overhead, as opposed to standard floor conveying systems.

It also ensures that the clothes are in better condition without folding it, and making it less crumpled as compared to belt conveyors. Products are needed to be folded and put in boxes or in plastic packaging before placing it on the conveyor belt. If the clothes are not packed, they might get dirty or damaged by the belts of the conveyors with the grease from it, staining on the clothes. Further more, the clothes might get stuck in the belt causing disruption to the system.

Additionally, it is economical as it makes use of the height of the warehouse building where the ground can be used for other activities. Unlike the belt conveyor, it only makes use of the ground, causing limited activities to be carried out in the warehouse.

Hence, the ideal choice will be overhead conveyor.

Case Study- New Balance Athletic Shoes

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New Balance Athletic Shoe, Inc. designs and develops innovative, highly functional and reliable shoes. Based in Boston, MA, New Balance has three North American warehouses (Ontario, CA, Compton, CA and Lawrence, MA) that process 26 million pairs of shoes per year.

Needing to maximize productivity in order to move the millions of athletic shoes sold annually, New Balance looked to Abel Womack to select just the right equipment for each of its various warehouse applications.

Solutions:

New equipment and systems acquired includes:

Counterbalance trucks for receiving
Wire-guided swing reach trucks and pallet trucks for pick and put away in narrow aisles
Wire-guided orderpickers for case picking

Facilitator's Question

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What are the constraints of crane and hoist in operations?

ANS:
The constraints of hoist is that there is a need take the weight usage into consideration. For example, package hoist is most suitable for light to moderate usage. When handling with heavy usage, we must use built-up hoist. There is also a need to minimise ratio of dead-weight to payload of the handling equipment.

The major constraint of jib crane is that it is stationary and cannot be moved easily from one work area to another. It is designed for positioning a work piece or tool, rather than for moving a product along in the work flow like an overhead crane.

It is also unsuitable to use when there is a need for precise locating of heavy loads, a large area of hook coverage, or frequent use for heavy loads. Another disadvantage is that the hook coverage is limited to the boom length (typically a maximum of 20 ft). The hook operates along a boom which rotates about a fixed point.

Whereas for bridge cranes or for all cranes, the constraint is the problems encountered when operating it. Problems such as crane travelling too far before stopping as electric motor brakes are being used, like most cranes, the brake pads haven't been replaced. They require replacing or adjusting every 3 months.

Other problems include bearings wearing out too soon, parts availability problems, and brakes wearing out or not working properly.

QUIZ TIME!

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After studying all the informations provided, I'm sure everyone is able to answer these questions:

1) Racks are considered what type of material handling equipment?
Ans: Storage equipment

2) What conveyor is this?Ans: Belt conveyor

3) Jib cranes can be moved easily from one place to another. True or False?
Ans: False

4) What device is used for lifting or lowering a load by means of a drum or lift-wheel around which rope or chain wraps.
Ans: Hoist

5) Pneumatic rotary indexing tables are suitable for small and medium loads or heavy loads?
Ans: Small and medium loads

6) What are 5 parts which bar-code symbol consists?
Ans: A quiet zone, a start character, data characters which include an optional check character, a stop character, and another quiet zone.

7) ______is an array of computerized routines for automatically receiving and shipping materials from defined storage locations without manual labor.
Ans: Automated Storage and Retrieval Systems (AS/RS)

8) What type of pallet is this?

Ans: Paper Pallet

9) _______ involves the use of at least two different modes of transportation in a trip from origin to destination, without handling the goods themselves in changing modes.
Ans: Inter-modal Container

10) ______ is the inter- organizational, computer- to- computer exchange of structured information in a standard, machine- processable format.
Ans: Electronic Data Interchange (EDI)