Introduction to Material Handling Equipment

There are thousands of pieces of material handling devices. These equipments vary from the most basic manual too to the most sophisticated computer-controlled material handling systems that can incorporate a wide range of other manufacturing and control functions.

Handling and storing materials involve diverse operations such as hoisting tons of steel with a crane; driving a truck loaded with concrete blocks; carrying bags or materials manually; and stacking palletized bricks or other materials such as drums, barrels, kegs, and lumber. The efficient handling and storing of materials are vital to industry.

In addition to raw materials, these operations provide a continuous flow of parts and assemblies through the workplace and ensure that materials are available when needed. Material handling equipment (MHE) is used for the movement and storage of material within a facility or at a site. MHE can be classified into the following five major categories:

• Transport Equipment. Equipment used to move material from one location to another (e.g., between workplaces, between a loading dock and a storage area, etc.). The major subcategories of transport equipment are conveyors, cranes, and industrial trucks. Material can also be transported manually using no equipment.

• Positioning Equipment. Equipment used to handle material at a single location so that it is in the correct position for subsequent handling, machining, transport, or storage. Unlike transport equipment, positioning equipment is usually used for handling at a single workplace. Material can also be positioned manually using no equipment.

• Unit Load Formation Equipment. Equipment used to restrict materials so that they maintain their integrity when handled a single load during transport and for storage. If materials are self-restraining (e.g., a single part or interlocking parts), then they can be formed into a unit load with no equipment.

• Storage Equipment. Equipment used for holding or buffering materials over a period of time. Some storage equipment may include the transport of materials (e.g., the S/R machines of an AS/RS, or storage carousels). If materials are block stacked directly on the floor, then no storage equipment is required.

• Identification and Control Equipment. Equipment used to collect and communicate the information that is used to coordinate the flow of materials within a facility and between a facility and its suppliers and customers. The identification of materials and associated control can be performed manually with no specialized equipment.

Did you Know? Traditionally, material-handling equipment may be grouped into 4 general categories and they are fixed-path system, the fixed area material handling system, variable-path variable-area equipment and the lastly the fourth category consist of all the auxiliary tools. In the first category (fixed-path system or also referred to as the continuous flow system) it consists of point-to-point equipments. This group of equipment serves the material handling need along a fixed path (like on a guided track).

The most common and familiar example of a fixed path system are trains and railroad tracks as trains can travel from any point to point, serving at any point that is along the track system. Other equipments under this category include the conveyor systems, powered, gravity-fed, automated guided vehicles and any other equipments that operate otherwise.

The second category is called the fixed area material handling system and this system can serve at any point within the three dimensional area or a cub. Examples such as the jib crane or the overhead traveling cranes can be installed on a floor pedestal to move parts and other material from any point to point in the x, y, z direction: however, this ability is limited within confines of the equipment. Automated storage and retrieval system (ASRS) also falls into this category.

AS for the third category, it consists of variable-material variable-area handling equipments or equipments that can move to any area of the facility.

Examples such as motorized vehicles, forklift trucks and all manual carts can be dragged, driven or pushed throughout the plant. Lastly, the fourth category consists of all auxiliary tools and equipments such as pallets, skids, automatic data collection systems, and containers Haha :)

That is all for our introduction to MHE. Although there is still much more categories of equipment in the industries, our group will be only focusing at the transport equipments and one of the positioning equipment which is the hoist for this assignment.

Hope that it stirs some interest in you!! Keep a lookout for more of our detailed findings to each of the equipments. Bye:)cya soon....

Answer to facilitator question

Facilitator's Question:
Explain the reasons of high popularity of counterbalanced forklift truck (as shown in your Bog) for material handling.

Answer:
Inventory reduction efforts over the past couple of decades have increasingly changed the focus from warehousing and storage density to material handling and speed. With current years, warehouses are becoming more movement and productivity focused and, in rapidly changing markets, flexibility and cost are getting a lot of attention.
The fact is, the standard wide aisle counterbalanced lift truck design that’s been used for more than 50 years still remains a very viable option. This is due to the flexibility to pick a load out of pallet rack and load it immediately onto a trailer combined with fast travel speeds (compared to the reach truck), a short learning curve, low cost, higher weight capacities. Additionally, with great variety of forklift attachment such as the clamps, side shift, load push pull and rotating head available, it gives the forklift a great versatility when loading different shape, size and weight loads. With a great variety of attachment, it also mean that there is no need to invest in different types of equipment for a specific job, just get a forklift and its attachment for the job. Furthermore, the cost in investing in a forklift is so much lesser compared to the other equipments such as the reach truck. Wide aisles also provide more flexibility with diverse load sizes and weights.

The table below gives you a comparision:
please view the table at this site: http://www.inventoryops.com/Aisle%20Width.htm

Lift trucks

Stacker Trucks:
These are light weight trucks, with maximum capacities up to about 2000kg, and can be pedestrian controlled and stand on .

Video on pedestrian Stackers

Free path high rack stacker.
These trucks up to 2 tones capacity, lift to about 12 M. they work in very narrow aisles between guide rails, with a mechanism on the mast which accesses stock from either side of an aisle. Since the truck does not have to turn to access the racks, the aisle width needs only to be slightly wider than the payload – about 1.5M in pallet racking. Some model have the operator at the ground level. In others, a rising cab raises the operator to working level

Stacker Crane
Stacker crane run between a floors mounted rail, and an overhead rail. They can single or twin mast (for heavy load), with a raising carriage for lifting abs lowering the load to the required height and for transferring the load into and out of the racking on either side of the crane aisle. They can have a rising cab for the operator, but they lend themselves to remote computer control. Drive in by an electric motor, while feed is by suspended of reeled power.

Side loader
Narrow aisle side loaders are the most space conserving mobile equipment for storeroom. The side loader has a mast, which reaches at 90 degrees to the direction of the truck travel and is used for loads up to 6 – 7M long handle in narrow aisle, or in outdoor stock areas. One of the most useful and unique use of the side loader is for the bar stock of up to 10 – 12 feet in length. There are many types of side loaders for different purpose, below are pictures of different side loaders used to different types, size, weight and shapes of load.

Fuel types for material handling equipment

There are many fuel types that can be use to run material handling equipment, below i have listed some examples.

Electric
Electric vehicles are designed for indoor use only. Their big advantages are the absence of fumes and their quiet operation. If you only intend to use your vehicles indoors, this is the way to go. In multi-shift operations you will need additional batteries and charging/transfer stations. In single shift operations, or, if the truck is not used 100% of the time, you can charge it during off hours. Note that the batteries and chargers for lift trucks are usually priced separately from the lift truck itself. You will also have choices of standard batteries or sealed maintenance-free types.

AC or DC
Recently AC (alternating current) motors are being offered by several lift truck manufacturers. AC powered lift trucks run off of DC batteries and convert the DC power back to AC to power the motor. The advantages of AC motors include faster acceleration, higher efficiency, and lower maintenance costs.

Regenerative braking
This technology recharges the batteries using the momentum of the lift truck when slowing down (braking). The frequent starting/stopping of lift trucks make them an excellent application for this technology. Similar to the technology used in hybrid automobiles.

Fast charging
Fast charging provides a means to reduce or eliminate the need to change batteries on multi-shift operations. The idea here is to quickly recharge the batteries during breaks, lunches, and between shifts (frequently called opportunity charging). Though more expensive than conventional charging systems, fast charging is growing in popularity.

LP Liquid Propane
Advantages of using LP include minimal fumes (however heavy use indoors requires adequate ventilation), the ability to use both indoors and outdoors, and the ability to quickly change LP tanks. Commonly used in indoor/outdoor operations such as lumber yards.

Gasoline or Diesel
Outdoor use only. Heavily used in construction, scrap yards, etc.

Fuel-cell Technology
There are a handful of companies already testing hydrogen fuel cell power sources for industrial trucks (more information on hydrogen fuel cells available at GeneralHydrogen.com , Hydrogenics.com or cellexpower.com ). The advantages of hydrogen fuel cell power include the ability to quickly refuel (similar to LP, Gas, or Diesel) avoiding the hassles and costs associated with battery changing/charging while providing the clean-air benefits of electric. Cost is still an issue at this point, but this is a technology to watch.

Truck attachment

There are an enormous variety of attachments and options available for lift trucks. While most attachments are designed for use on standard lift trucks, some of them are also used on reach trucks and VNA trucks. It's important to note that OSHA (Occupational Safety and Health Administration) requires that for any forklift attachment used, there must be an approval for use by the specific lift truck manufacturer. This regulation requires the buyer to go through the OEM (Original Equipment Manufacture) dealer for the purchase and installation of the attachment.

Forks are the most common attachment; they're not always the best solution for every application. In pursuit of higher productivity, less product damage and reduced worker injuries, many loads require an attachment other than a fork – clamps and push/pull units, for instance. And even if forks are the tool of choice, attachments such as side shifters and fork positioners are valuable aids for improving load handling.

Attachments also allow users to reach to higher heights, to reach further out and to move heavier loads than could be moved manually. Attachments, when applied properly on a lift truck, substantially increase the amount of work that can get accomplished in the course of a day.

Additionally, attachments protect operators from ergonomic stress by keeping them on the seat of the truck rather than lifting, pulling or tugging loads that couldn't be moved with conventional forks.

Note that most attachments will change the capacity of the lift truck and a new placard should be placed on the truck showing the new specs

Below I will list some of the more common types of attachments.

Side shift
This is the most common attachment today the side shifter operates with a standard pair of forks. Operators can reposition the forks (allows the fork carriage to slide left and right) rather than reposition the truck by maneuvering it repeatedly in forward and reverse. This allows more accurate placement of the load as the forks or other attachment to be shifted by about 75MM. Side shifts will increase productivity and safety as well as reduce product damage by allowing the operator more flexibility in load placement. Side shifters are available as both single and double units, capable of handling one or two pallets at the same time

Fork positioner

With the variety of pallet dimensions out there, each with different pallet notch spacings, it would be impractical to have multiple lift trucks designated to handle each size. It would also be a very timely undertaking for an operator to have to climb down from the cab and manually adjust the fork spacing before every pick up.
Fork positioners, usually hydraulic-powered, are a solution. This device automatically adjusts the distance between the forks to handle an infinite number of pallet sizes, without the operator ever leaving the seat of the truck. In addition to the time savings, fork positioners also reduce the potential for back injuries or pinched fingers that could result from manual adjustments. Used primarily in high volume operations where there is a great variety of pallet and crate sizes handled.

Clamps
These are operated from the fork truck hydraulic system with movable and sometimes shaped arms for handling cartons, bales, reels and drums. Clamp attachments literally clamp opposing sides of a load, applying a sufficient amount of pressure to lift the load in a controlled manner without crushing or dropping it. Used in a range of applications, clamps handle loads that simply aren't transportable by pallet.

There are two types of clamp mentioned here, they are:

Carton clamp
Flat surface carton clamps are often used in the appliance industry to move high-bulk, low-weight items like refrigerators, washers, dryers, ovens, dishwashers and more. They're also used to move unit loads of beverages stacked without slip sheets or pallets.

Paper-roll clamp

Concave surface paper roll clamps designed specifically for the handling of large paper rolls. usually used in the paper and printing industries to move large rolls of paper throughout a facility. Clamps are also used to position rolls on equipment that converts raw paper into consumer goods like paper towels, toilet paper and tissues. the paper roll clamp clamps around the roll and also allows for a full 360 degree rotation

Load Push/pull units
Push/pull attachments work with loads on cardboard or plastic slip-sheets with a lip. The attachment clamps on to the lip and pulls the load onto a set of wide, low profile forks for transport.Once the load reaches its destination in the warehouse or on the trailer, it is then pushed off the forks by the attachment. They are most often used in situations where a facility has elected to eliminate pallet usage to cut costs. These attachments are also often found in food-processing applications, where users have replaced pallets with slip sheets for hygienic and sanitary reasons.

Multiple pallet handlers
Multiple pallet handlers can double or triple lift truck productivity by adding a second or third pair of forks to the truck. Some attachments handle loads that are two pallets deep.
By allowing operators to pick up more than one load at a time side by side, a greater number of pallets can be transported throughout the day. Multiple pallet handlers are most frequently found in high-volume operations such as beverage and food handling.
These attachments do present some limitations in horizontal clearance, limiting their access to certain aisles or other areas. However, some models feature retractable forks that permit single load handling and can travel through narrow aisles and doorways.

Rotating head
This device helps to change the orientation of a load, eg, a reel which is delivered horizontally and is needed to be stack vertically.

Rotators
This attachment features forks mounted on a rotating apron that turns anywhere from 180 to 360 degrees. Rotators are most often used in operations where bulk bins or containers store and transport large volumes of small items. Once the truck has delivered the bin to its destination, the rotator turns to dump the contents out into another hopper or processing station.
These attachments are used extensively in scrap metal applications. Other uses include food and wine processing. Rotators are part of the sorting and production process as bins of fruits and vegetables are received from the fields and then poured into processing equipment.

Drum handling attachments

There are a lot of different designs for attachment used to handle 55 gallon drums. Some are smaller versions of a paper roll clamp while others may engage the upper rim of the drum, or the lower rings. Some drum attachments are capable of picking up multiple drums at the same time.

Prongs

A Prong is a specialized rod type attachment used for picking up rolls of materials such as carpet rolls, wire and cable spools, and rolled steel, by inserting the prong into the center of the spool.

Fork extensions

Fork extensions slide over the existing forks on the truck to allow you to pick up longer loads.
Height selector. A height selector is an option that allows you to preset certain fork heights to correspond with rack levels. This option is most commonly used on reach trucks working at heights above 20 ft.

Tilt control

Tilt control allows you to preset fork tilt angles.
Fork pivot. Allows the forks and carriage to pivot (rotate). Used for transporting and dumping specially designed hoppers.

Slip sheet atachment

Slip sheet attachments are used where slip sheets (a sheet of cardboard, paperboard, or plastic) are used rather than pallets. The slip sheet attachments has a push/pull mechanism that clamps onto the slip sheet and pulls the load onto a thin platform and then pushes the load off of the platform when the truck reaches the destination.

Latest trend
For the future of lift truck attachments, suppliers are working to develop higher levels of monitoring attachment use through bar coding and radio frequency identification (RFID) tags. "These technologies provide opportunities to embed information such as the clamp forces required to handle a product safely without overclamping and crushing the load," explains Mike Kern, vice president of MHP marketing and sales at Cascade Corporation." Even though operators have attachments now, they don't always know when it's appropriate to change from one setting to another. This technology makes it easier for the user not to have to make a determination and it helps to increase productivity.

For more information, please visit these sites:

OSHA: http://www.osha.gov/

OEM: http://en.wikipedia.org/wiki/Original_equipment_manufacturer

Reach Truck

The reach truck is a loading device that is used by a number of different types of businesses that maintain a storage area that involves the arrangement of supplies and finished goods on pallets that are inserted into tall shelving structures. It is also a narrow aisle (8'-10') truck designed specifically for racked pallet storage. The reach truck provides safe and easy retrieval of the loaded pallets, as well as efficiently storing pallets of goods that are not required for immediate use. Using a reach truck to store supplies, pallets of finished goods, and in general to keep the storage area in order is a common practice. It also consists of outriggers in front and telescoping forks that use a hydraulic scissors type mechanism that allow you to pick up the load and retract it over the outriggers reducing the overall truck and load length allowing you to turn in a narrower aisle. Reach trucks are driven electrically with AC technology. Double-deep versions use an extended reach mechanism that allows for storing pallets two deep in specially designed double-deep rack. Two pallets deep will save about 50 percent of the aisle space. Double deep reach trucks are also known as stand up reach, straddle reach, and double-deep reach. Reach trucks is easy to operate, the reach truck can help make better use of both time and available storage space.

Here is a description (characteristic) of the basic reach truck, as well as examples of the three main types of reach trucks.

Characteristic:
The basic reach truck has an outrigging mechanism on the front of the truck. Mounted to the outrigging is a set of telescoping forks that move up and down. The forks also include a hydraulic setup that allows the operator to pick up the load and reposition it over the outriggers. This not only provides a more even balance of the load, but also makes it easier to maneuver the reach truck into narrow aisles between the storage shelves.

When the reach truck arrives at the shelves designated for the pallet, the hydraulics allow the forks to swing and lower the pallet into the shelving, sliding the pallet into place. Generally, a reach truck will easily fit into an aisle that is less than ten feet across with no problem, assuming there are not pallets sticking out from the shelving.

Three different examples of reach trucks:

Reach truck
There are several models of the reach truck. The stand-up reach model is the most simple. Essentially, this basic reach truck will slide the forks under the pallet, transport it to the desired storage location, and slide it into place. For shelving units that are no deeper than required to place one pallet of goods, this type of reach truck is ideal.

The second variation is the Straddle reaches. Essentially a mode of reach truck that can not only slide under the pallet, but also grab the sides as well, the straddle reach model works well when grasping the sides of the pallet and goods will not result in damage. These can be helpful when the shelving units are accessible for more than one direction, allowing the easy retrieval of a pallet that may be third or fourth in the line.

Has a lifting capacity from 1000kg - 3500kg with a maximum lifting height of 8M. Able to work in aisles as narrow as 2.7m.

Double-deep reach truck
The double-deep reach truck is the third variation of reach truck. It performs in the same basic manner as the stand-up type, but has telescopic forks that are long enough to slide a pallet into place when the shelves are deep enough to accommodate two pallets of goods. Because the double-deep reach truck can easily place the pallet at the back of the shelving unit, there is no need to push the pallet back when there is another pallet to go into the same shelving section.

Video on reach truck

Warehouses often make use of one or more types of the reach truck, as well as the supply areas for many textile firms and manufacturing facilities. Using a reach truck to store supplies, pallets of finished goods, and in general to keep the storage area in order is a common practice. As a device that is easy to operate, the reach truck can help make better use of both time and available storage space.

The reach trucks has an advantage that during horizontal movement, the load is carried within the area enclosed by the truck wheels and this allows a shorter overall length than the CBFLT and eliminates the need for a counter-balance weight.

However the down side of the reach truck is ergonomic factor of the reach truck. Especially for the 30 feet reach truck as it becomes very difficult to place loads at that height and puts a lot of strain on the operator's neck and eyes.30 feet as it becomes very difficult to place loads at that height and puts a lot of strain on the operator's neck and eyes.

Operator have to lift the head very often to see where is the load to pick (as seen in the picture). This causes strain on the neck. Thus, the ergonomic challenge, then, is to position the operator relative to the truck to safely take advantage of this performance, yet avoid the musculoskeletal extremes of posture that lead to soft tissue damage and repetitive motion disorders.

To analyze and then design this operator/truck system, we must ask these questions:
What is this merged man-machine system required to do? What are its tasks? To get the answers we must conduct a task analysis that consists of an examination of how the truck is used in the warehouse, and then analyze how the operator relates to both the tasking and to the truck to accomplish this tasks. To get more information of the reach truck application and ergonomic, please visit this site: http://www.raymondcorp.com/das/PDF_storage/TechnicalPapers/Form0052.pdf

To resolve such a problem and to improve on ergonomic, presents reach trucks that has an adjustable seat. this helps to improve visibility, stability and operator comfort.

Reach truck with a adjustable seat to allow better visibility ans reducing the strain on the operator's neck

For more information on the reach truck with the adjustable seat, please vist this site: http://www.ferret.com.au/c/Toyota-Material-Handling/Bt-Reflex-Reach-Truck-With-Tilting-Cabin-p12537

Non-Lift truck

There are various type of non-powered trucks and trolly, often designed for various appliccation. There are two-wheel hand truck, four wheel hand cart, powered or non powered pallet hand jack and lastly tugs and tractors.

Two-wheel hand cart
Weights up to 500pounds and can be moved by a single person with goods on the two-wheel hand truck. this hand truck can be used in every area of a business, even in the office.

2 wheel hand cart

Four-wheel hand cart
There are hundreds of shapes and sizes, and uses of hand carts. You can build any shape om the platform and move very special materials. Such as the four wheel hand carts, they are very versatile, many things (goods) can be loaded and moves nearly anywhere.

4 wheel hand cart, versatile, can be chsnge for any purpose

Pallet hand jack (Pallet truck-hydraulic lift)
A pallet jack, also known as a pallet truck or pump truck, is 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 hand jack
Pallet hand jacks are rolled under a pallet, the handle is pumped (hydraulic pump handle), the pallet is lifted of the floor a few inches, and now the pallet up to 900kg of material can be moved easily by hand.

Manual pallet hand jack

Powered pallet hand jack
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. Some contain a type of deadman's switch rather than a brake to stop the machine should the user need to stop quickly or leave the machine while it is in use.

Powered pallet hand jack

Operational limitations:

• Reversible pallets cannot be used.
  
• Double-faced nonreversible pallets cannot have deckboards where the front wheels extend to the floor.
  
• Enables only two-way entry into a four-way notched-stringer pallet, because the forks cannot be inserted into the notches.
  

Video on Pedestrian Powered Pallet Trucks



Tugs and tractors
Tugs and tractors are used for long horizontal movement. Tugs maybe more economic and appropriate than forklift trucks when the loads are being carried on paltform or trailers.

Examples of Automated Guided Vehicles (AGV)

These are the examples of company that adopted. It provide automated material movement for customers in a variety of industries including the: automotive, chemicals/plastics, hospital, newsprint/newspaper, commercial print, paper, food & beverage, pharmaceutical, warehouse and distribution center, and manufacturing industries.

A video of a AGV counter balance truck


A video of Unit Load (AGV)


A video of Narrow Aisle (AGV)



A video of Roll Delivery Fork Lift AGV - Automated Guided Vehicle

Overview of 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. The load is attached to the hoist by means of a lifting hook.

Types 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. The power type can be either electric motor or air motor.

Both the wire rope hoist and chain hoist have been in common use since the 1800s. 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. The built-up hoist will be much more expensive, but will also be easier to repair and more durable.

Package units are designed for light to moderate usage, while built-up units are designed for heavy to severe service. A machine shop or fabricating shop will use an integral-package hoist, while a Steel Mill or NASA would use a built-up unit to meet durabilty, performance, and repairability requirements.

Construction hoists:

Also 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 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.

comparison between conveyors, trucks and cranes/ hoist

For comparison between the three MHE you can go to this site:

http://www.mhia.org/et/pdf/mhi/cicmhe/equpguid.pdf

overview of crane

A crane is a mechanical lifting device equipped with a winder, wire ropes and sheaves that can be used both to lift and lower materials and to move them horizontally. It uses one or more simple machines to create mechanical advantage and thus move loads beyond the normal capability of a human. Cranes are commonly employed in the transport industry for the loading and unloading of freight; in the construction industry for the movement of materials; and in the manufacturing industry for the assembling of heavy equipment.

The first cranes were invented by the Ancient Greeks and were powered by men or beasts-of-burden, such as donkeys. These cranes were used for the construction of tall buildings. Larger cranes were later developed, employing the use of human treadwheels, permitting the lifting of heavier weights. In the High Middle Ages, harbour cranes were introduced to load and unload ships and assist with their construction – some were built into stone towers for extra strength and stability. The earliest cranes were constructed from wood, but cast iron and steel took over with the coming of the Industrial Revolution.

Cranes exist in an enormous variety of forms – each tailored to a specific use. Sizes range from the smallest jib cranes, used inside workshops, to the tallest tower cranes, used for constructing high buildings, and the largest floating cranes, used to build oil rigs and salvage sunken ships.

General characteristics of cranes:

• Used to move loads over variable (horizontal and vertical) paths within a restricted area


• Used when there is insufficient (or intermittent) flow volume such that the use of a conveyor cannot be justified


• Provide more flexibility in movement than conveyors


• Provide less flexibility in movement than industrial trucks


• Loads handled are more varied with respect to their shape and weight than those handled by a conveyor


• Most cranes utilize hoists for vertical movement, although manipulators can be used if precise positioning of the load is required
  

Lifting capacity:

Cranes illustrate the use of one or more simple machines to create mechanical advantage.

The lever. A balance crane contains a horizontal beam (the lever) pivoted about a point called the fulcrum. The principle of the lever allows a heavy load attached to the shorter end of the beam to be lifted by a smaller force applied in the opposite direction to the longer end of the beam. The ratio of the load's weight to the applied force is equal to the ratio of the lengths of the longer arm and the shorter arm, and is called the mechanical advantage.

The pulley. A jib crane contains a tilted strut (the jib) that supports a fixed pulley block. Cables are wrapped multiple times round the fixed block and round another block attached to the load. When the free end of the cable is pulled by hand or by a winding machine, the pulley system delivers a force to the load that is equal to the applied force multiplied by the number of lengths of cable passing between the two blocks. This number is the mechanical advantage.

The hydraulic cylinder. This can be used directly to lift the load (as with a HIAB), or indirectly to move the jib or beam that carries another lifting device.

video of overhead crane

overhead crane

Also known as a "suspended crane", this type of crane works in the same way as a gantry crane but without uprights. The hoist is on a trolley which moves in one direction along one or two beams, which move at right angles to that direction along elevated tracks, often mounted along the side walls of an assembly area in a factory. Some of them can lift very heavy loads.

Overhead cranes are used in many industries to move heavy and oversized objects that other material handling methods cannot. These cranes have a railed support structure called a bridge, and a wheeled trolley that travels across the bridge horizontally. Several varieties of overhead cranes exist including gantry, semi-gantry, cantilever gantry, storage bridge and wall cranes.

The advantages of cranes :

• Higher hook lift, since the hook can be pulled up between the main girders.
• Extremely rigid box girder construction and durable trolley design are well suited for heavy service applications.
• Light weight = lower wheel loads (less building steel)
• Low head room monorail hoist
• Lower production costs
• Ease of maintenance
• Ease of installation

Inspection Requirements - safety requirement :

Due to the large and heavy objects often being transported by overhead cranes, routine inspections are necessary to ensure continued operation of the crane and the safety of the employees around the crane. An initial inspection of the crane prior to initial use of new and altered cranes is necessary.

Once placed into service, overhead cranes will require two different types of inspections. Frequent inspections are done at daily to monthly intervals, while periodic inspections are completed at monthly to annual intervals. The purpose of the two inspection types is to detect critical components of the crane and to determine the extent of wear, deterioration or malfunction.

Items to be Inspected -

Hoisting and lowering
Trolley travel
Bridge travel
Limit switches, locking and safety devices
Load test of not more than 125% of rated load

video of stacker crane

stacker crane

A crane with a forklift type mechanism used in automated (computer controlled) warehouses (known as an automated storage and retrieval system (AS/RS)). The crane moves on a track in an aisle of the warehouse. The fork can be raised or lowered to any of the levels of a storage rack and can be extended into the rack to store and retrieve product. The product can in some cases be as large as an automobile. Stacker cranes are often used in the large freezer warehouses of frozen food manufacturers. This automation avoids requiring forklift drivers to work in below freezing temperatures every day.

Similar to a bridge crane except that, instead of a hoist, it uses a mast with forks or a platform to handle unit loads . Considered "fork trucks on a rail"

Used for storing and retrieving unit loads in storage racks, especially in high-rise applications in which the racks are more than 50 feet high . Can be controlled remotely or by an operator in a cab on the mastCan be rack supported.

Stacker cranes can be used for a variety of other lifting and position tasks such as loading small bins or tubs on and off of shelves in a storage area, for handling small pallets or other payloads. Custom designed tooling can adapt the stacker crane to a wide range of applications.

Stacker crane in ASRS:

Installs stacker cranes to be used in the automated storage and retrieval systems. The stacker crane can be used to store and handle large units that a forklift would not have been able to do so. It is integrated into the automated storage rack for easy and fast handling Employees would not have to wait for a forklift to be accessible. It will only take minutes for the stacker crane to retrieve items. The stacker crane will increase material productivity and reduce any needed floor space.

Stacker Cranes provide solutions to several industrial applications while providing an easier, faster, and safer process. These systems are often used in applications where fork trucks can not easily maneuver, where precise control of the load is needed, and/or for articulated product handling associated with machining centers, furnace applications, etc.

Key Benefits:

maybe able to handle deep load handling devices
High reliability of operation
Ease of maintenance and service
Simple installation
Extremely lightweight design
Fast operation

Applications include:

WIP or maintenance areas
Tooling & fixture storage
Die & mold storage
Drum & barrel storage
Motor & pump storage
Roll handling
Pipe, sheet metal, bar stock, etc.
Automotive or aircraft parts
...and many more

Order Picking Truck

Order picking is the most time consuming and often the most expensive stage in materials handling. With a proper toll order picking can be handled efficiently. with the use of order picking trucks, it helps to increase the efficiency and effectiveness of order picking operations as well to improve the constantly more important ergonomics.

For this posting, i will touh on:

1. The Characteristic of Order Picking Truck
2. Low-level Order Picking Truck
3. Intermediate Order Picking Truck
4. High-level Order Picking Truck

Order picking lift truck is ideally suited for a wide variety of order picking operations found in: warehouse and distribution centers, manufacturing plants, beverage and food processing plants, third party logistics providers and e-commerce companies, among others. Powerful, 3-phase AC motors for travel, lifting and steering provide the muscle and control to perform order picking tasks with minimal effort, even in high racking warehouse operations

Characteristic:
An order picking truck, in particular a high-lift order picking truck, is equipped with a driver's stand , a load-picking fork and a wall separating the driver's stand from the load area. The fork is secured on an initial lift device so that it can be moved up and down relative to the driver's stand . According to the invention, an additional lift device is provided with which a load on the fork can be raised beyond the highest position of the initial lift device. The fork has two-part fork tines which each have a load picking upper part and a lower part secured to the initial lift device. Each two-part fork tine includes a scissor construction guiding the upper part of the tine parallel with the lower part of the tine.

This free path trucks for order picking are available for low level picking, intermediate and for high level picking.

Low-level Order Picking Truck

The low-level order pickers, which are for high frequency order picking have a picking height of up to 3.5 metros, width of the driven platform is 80 meters to 120meters and has a maximum driving speed of 9km/h

Video of Low-level Order Picking Truck

Intermedia level Order Picking Truck



The intermediate level order picking truck load capacity of 600 - 1000kg and a maximum picking height of 6.5 -7 meters, medium-level order pickers were suitable for goods that were bulky but not too heavy, for example, automotive parts.

Video on the intermediate level order picking truck




High-level Order Picking Truck

The high level order picking truck high-level order picking, which are for low frequency orders have a maximum picking height of up to 9.5 meters and some may have a maximum picking height of 10.5 meters. It also has a optimum picking area which starts at 5meters and it is able to handle tuck load capacity of 800kg – 1000kg depending on the different chassis widths or lengths on need of use. The truck can be driven anywhere in the warehouse and in rail-guided aisles.

Latest trend:

AC technology is used in the truck's in-service capabilities and performance with low energy consumption through more efficient electrical management systems. A regenerative lowering and braking design feeds energy back into the truck supply system prolonging in-use operation cycles and reducing the time needed to recharge batteries. Energy costs are lower, and the overall cost of ownership is significantly reduced.The truck's cushioned stand-on platform allows the operator to effortlessly maneuver individual items from the racking. The economically designed cab features a compact operating panel with a graphic display, including: battery discharge monitor, operating hour meter, key switch, emergency stop switch, clock, and lift height and steering position indicators. The cab allows the operator to either stand or sit providing a user-friendly work environment.Many operator functions can be easily accomplished with one hand due to a variety of ergonomically positioned motion controls. Each operator's touch (sensitivity) is individually adjustable for comfort and operational efficiency. Switch-free sensors calibrate the operator's touch and then pass the information to the onboard computer where all safety checks are verified.

video of wire rope hoist - e.g.

wire rope hoist

Electric wire rope hoists can be provided in any configuration available, whether it be single hook, twin hook or multiple hook models utilizing lug, floor, ceiling or trolley mounting, we can provide it for you.

Electric Wire Rope Hoist are suitable for medium and heavy duty operations. The hoists are designed in modular construction with each component easily accessible for maintenance. The Rope drum, Gear Box, Motor, Brake and Panel can be easily attended to. The frame is of sturdy design fabricated from steel plates and is welded / bolted type.

Disadvantages of wire rope -

Wear on areas in contact with hoist sheaves and drums.

Corrosion from lack of lubrication and exposure to heat or moisture (e.g., wire rope shows signs of pitting).

A fibre core rope will dry out and break at temperatures above 120°C (250°F).

Fatigue from repeated bending even under normal operating conditions.

There is the safe working load limit.

Kinks from improper installation of new rope, sudden release of a load or knots made to shorten a rope. A kink cannot be removed without creating a weak section.

safety precautions:

Inspect wire ropes -

Only trained personnel should carry out an inspection of wire ropes.
Inspect a wire rope when installing it.
Inspect wire ropes every working day.
Keep records of daily inspections.
Check for abrasions, corrosion, pitting, and lubrication inside rope. Insert a marlin spike beneath two strands and rotate to lift strands and open rope.

When should you eliminate the rope from its use -

Assess the condition of the rope at the section showing the most wear. Discard a wire rope if you find any of the following conditions:
In running ropes (wound on drums or passed over sheaves), 6 or more broken wires in one lay length; 3 or more broken wires in one strand in one lay.
In pendant standing ropes, 3 or more broken wires in one lay length.
Wear of 1/3 of the original diameter of individual outside wires.
Kinking, crushing, cutting or unstranding, bird caging or other physical damaged that has distorted the shape of the wire rope.
Heat damage (check for burn marks, discoloration of the metal).
Excessive stretch or sharp reduction in the rope diameter.
Knots or splices (except eye splices) in a wire rope.

Latest trends of wire rope hoist:

The Spacemaster® SX represents a revolutionary new generation of exceptionally reliable electric wire rope hoists, featuring advanced technology and cutting-edge performance.

An innovative design that includes a large drum diameter gives Spacemaster® SX hoists the lowest headrooms and best wheel loads in the industry while providing near true vertical lift with single reeved hoists, and both exceptional hook approaches and heights of lift.

Unique features include new low maintenance, sealed brakes, a two-speed hoist motor, and trolley inverter control. The standard hoist nameplate will carry a CSA c/us rating as well as a rating for electrical enclosures. Two-component epoxy paint is standard. Hoists are designed to meet and exceed previous duty (FEM 1Am, 2m, or 3m) ratings and provide the ultimate in easy load handling, safe operation and lasting, trouble-free performance.

EASE OF OPERATION:

Large-diameter hoist drum means easy positioning, closer approaches.The larger drum diameter provides near true vertical lift with a single reeved hoist . The result is exceptionally smooth movement and fast load positioning.

This design also means a shorter frame length, allowing closer end approaches. Hoist and trolley motors designed for space savings and productivity.Standard two-speed hoist motor designed specifically for hoisting applications, offers high starting torque and ensures precise and reliable load handling.

The trolley motor's standard inverter control offers two-speed multi-step or infinitely variable speed control for smooth acceleration and deceleration, minimal load swing, fast, efficient handling and accurate load placement.

SAFETY :

Standard safety features . An electromechanical load limit switch prevents the lifting of loads that are in excess of 110% of rated capacity. The 4-position hoist limit switch includes an innovative phase mismatch protection circuit that prevents the block from running up and damaging the hoist in the event of phase reversal.

Sealed brakes, hardened ground gears, thermal motor protection, exceptional rope life and ergonomic hook block design with sturdy safety latch contribute to the hoist's safe operation and increased reliability.

LESS MAINTENANCE:

Sealed brakes mean long-term value.Sealed dust-proof brakes on the trolley and hoist motors require little adjustment for over a million cycles and will last the life of the hoist under normal use. Trolley design reduces wear on components.

The trolley drive is totally enclosed, grease lubricated and is designed to be maintenance-free. Trolley wheel bearings are permanently lubricated. The automatic disc brake and inverter control help extend the life of the motor and other components, which means less maintenance, less downtime, lower repair costs — and reduced cost over the lifetime of your hoist equipment.

LONG LIFE :

Innovative gearbox provides dependable operation and extends equipment life.The innovative gear case design reduces stress on drum bearings, reducing the need for maintenance while extending component life.

It features hardened and ground internal reduction gears driving an external drum gear located on the inner surface of the rope drum. The gearbox's semi-fluid grease lubrication also helps to extend its working life. The gear case is designed to run cooler and more efficiently than those equipped with a mechanical load brake.

Larger hoist drum minimizes rope wear and enhances cooling.A drum/rope diameter ratio of approximately 40:1 minimizes rope flex, reducing wear and extending rope life. The drum's large diameter also contributes to a reduction in frame size and weight, reducing wear on hoist components and enabling the use of more cost-effective crane girders. The unique placement of the hoist motor inside the drum provides directed airflow through the drum for optimal motor cooling. This design also makes the motor and brake more easily accessible.

video on chain hoist - e.g.

chain hoist

Used for vertical translation (i.e., lifting and lowering) of loads. Frequently attached to cranes and monorails to provide vertical translation capability Can be operated manually, electrically, or pneumatically



A chain hoist is a mechanical device used for lifting heavy loads of objects and equipment. It is made with a pulley, which is held together by a closed chain. The closed chain in the chain hoist forms a loop, which makes it easy to be pulled by hand.
Chain hoists are typically electrically powered, but can be manually or pneumatically operated as well. In a chain hoist, the chain is attached to a lifting hook on one end and a drum wheel on the other. To lift, the crank turns the reel and wraps the chain around the spool, raising the load at the end of the hook.

There are several large and small pulleys located throughout a chain hoist. One large and one small pulley are situated on the same axle of the chain hoist. There is also a mobile pulley on the chain hoist that holds the load in place.

For the load to be raised with the chain hoist, the closed chain has to be pulled. When it is pulled, the large pulley draws in more chain than what is released by the smaller side. From here, the lifting process begins.

Although the history of pulleys is unclear, it is known that primitive methods were employed to move heavy objects around. One of the early attempts at a pulley system was the single fixed pulley, which failed because friction prevented the wheel from being turned. Rope pulleys, which were commonly used for pulling water out of wells and are still in use today, are thought to have been invented next.

There are three types of chain hoists: air, manual, and electric. The manual chain hoist and the air chain hoist are designed with reduction gears, hook pivots, and swivels. Suspended by a top hook, or by a push or geared trolley, these types of chain hoists move objects slowly and carefully while making height adjustments. The attached load is well secured so it can be left fixed without requiring a great deal of supervision.

The electric chain hoist, on the other hand, is generally used for lifting heavy-duty industrial loads. The electric chain hoist allows the user to pull from the side as well as vertically.

In industrial settings, chain hoists are most often used to lift items vertically. Chain hoists are available in multiple varieties; they differ by diameter, load capacity, line material, length, and maximum loaded line speed. Choosing the hoist that fits the needed specifications is important, because safety issues can arise if hoists are misused.

Benefits:

Chain hoists offer many benefits. First, metal chains are more durable than rope. In addition to their durability, roller or link chain hoists are popular because they are fairly simple and inexpensive. They also require a low level of maintenance and are able to survive high temperatures without suffering damage.














Electric Hoists:

Industrial hoists are widely used for lifting. They are generally inexpensive and reliable. They increase the safety associated with lifting and enable the movement of much larger unit loads than would be possible with many other economical lifting options. An electric hoist can be defined as a suspended machinery unit using wire rope or chain for vertical lifting or lowering of freely suspended unguided loads.

Because the primary reason cited for hoist failure is the failure to consider the duty environment of the hoist, it is useful to consider duty factors in the hoist selection process.

Applications :

Hoists are versatile and we supply a broad range to meet most applications from lifting of small and light objects to larger hoists for factories and areas where lifting of heavier objects is required.

latest trends of electric hoist:

The new XN electric chain hoist , is a compact, efficient hoist combining reliability with style, safety with performance, and high technology with modern design. The XN hoist is the most cost-effective and reliable solution for light to medium hoisting needs.

Packed with benefits, the XN hoist features technical excellence and quality, unmatched versatility, safety and reliability, and a lifetime support system.Each XN hoist is extensively tested before delivery, undergoing a dynamic load test using 125 percent of its rated capacity.

The hoists go through overload and reduced voltage electrical tests as well as operational tests. Each hoist is CSA certified and meets or exceeds international standards, including ASME B30.16.The XN hoist is ideal for a wide range of applications.

Versatility features include a manual or electric trolley with one or two-speed hoisting options, a 1/8 - 5 ton (125 - 5000 kg) capacity range, and a standard lift height of 10 feet (3 meters) with other lifts available.

The five and six pocket chain wheels are heat-treated and ground to a high tolerance, providing especially smooth lifting. The load chain is electro-zinc plated, heat-treated, and has a high tensile strength. The lifting hook is made of high grade steel and is provided with a safety latch.

Maximum reliability and safety features on the XN hoists include high quality disc brakes, optional upper and lower limit switches, and a friction type torque limiter that is integrated with the brake; ensuring the load is always stopped when the control button is released, even if the torque limiter slips. Efficient heat dissipation is achieved via its ribbed design.

video of scissor lifts- e.g.

scissor lifts

Scissor lifts are a specialized type of aerial lift, designed to lift larger loads and provide more work space. For manufacturing or industrial work where multiple workers need to be on the same platform, a scissor lift is a must-have.

A scissor lift can be powered by gas or electricity. Diesel or gas-powered scissor lifts – often called rough terrain scissor lifts – are better for outdoor use, but can’t be used indoors. Electric scissor lifts are quiet and emission free, which makes them a better choice for use in warehouses or other indoor work.

The most basic consideration when choosing a scissor lift is the height you need to reach. Because the strength of a scissor lift is the size of the platform and weight it can support, you may not find the same lift heights you would in other types of aerial lifts: most can reach heights of 20 to 50 feet. You’ll also need to consider lifting capacity: most scissor lifts can carry from 500 to 2,500 lbs.

While most scissor lifts can only lift straight up and down, some have a feature that lets you shift the platform horizontally several feet. Others allow you to drive the machine around while the platform is raised – but not all do.


Types of scissors lift:

Hydraulic Lifts

Hydraulic scissors lifts provide the most economical, dependable, and versatile method of lifting heavy loads. Hydraulic lifts have few moving parts, are well lubricated, and provide many years of trouble free operation. These scissors tables raise the loads smoothly to any desired height, and can be easily configured to meet the specific speed, capacity, and foot print requirement of any hydraulic lifting application. Each hydraulic scissors lift is designed and manufactured to meet the industry safety requirements and is by far the most popular and efficient of all styles of scissors tables used in material handling applications.

Air Bag Lifts

Air actuated scissors lifts provide durable and safe lifting solutions for applications which require pneumatic operation rather than hydraulic, such as explosion-proof or environmentally sensitive locations. These scissors lift tables are powered by heavy-duty air bag actuators which are connected to your plant’s shop air system. Air bag scissors tables are used in a wide variety of applications to improve worker ergonomics and enhance plant efficiencies. Air actuated scissors lifts offer a durable, low precision, low cost and portable lifting solution which can be purchased standard, or customized to fit specific material handling application requirements.

Double Scissors Lifts

Double pantograph hydraulic scissors lifts provide the most economical, stable, and versatile method of lifting heavy loads with higher vertical travel while maintaining the smallest footprint possible. Double pantograph scissors tables use a one-piece, double scissors mechanism, and can be easily configured to meet the specific speed, capacity, and footprint requirement of any hydraulic lift application – without the need for permanent guides and structure above the lift. Common applications for double pantograph scissors lifts include mezzanine access and storage, pallet build-up and break-down of tall stacks, adjustable work platforms, conveyor transfer, and floor to floor movement of wheeled loads.

Ground Level Lifts

The Ground Level scissors lifts provide the near-zero lowered height of a traditional pan-style scissors lift with the extremely low reach-over distance previously available in expensive mast-style lifts. The XLR family of scissors lifts is designed for material handling applications where pallet jacks or other wheeled carts are used to transport loads that need to be raised – but without having to dig a pit to recess a conventional scissors table. These scissors lifts raise or lower the loads smoothly to any desired height for worker ergonomics or to change elevations inside the plant. The family of scissors lifts is available in either hydraulic or pneumatic actuation, and can be customized for a wide variety of applications.

Mechanical Lifts

Autoquip offers a variety of mechanically actuated scissors lifts depending on the application, environmental conditions, load restrictions and life cycles desired. All Mechanical scissors tables are designed for satisfying specialized applications requiring precise travel heights and offer repeatability in elevation to .06” accuracy. In addition to precision, Mechanical scissors lifts also can be easily programmed for automated systems, and – unlike most hydraulic lifts – have the ability to remain loaded in the raised position over long periods of time without drifting down. The most common applications for mechanical lifts are in clean room environments, explosion-proof atmospheres, food processing, and automated or PLC controlled systems.


The Benefits:

• The dangerous practice of using a ladder to work on was eliminated.


• Productivity and safety were improved - provide a safer work environment for your employees and make it easier for them to meet requirements that call for people working more than six feet above ground level be protected from falls. The guardrails on a scissor lift fulfill those requirements.


• Another feature of scissor lifts is their versatility. Most frequently they are used inside, but they are also suitable for outdoor use as long as they are operated on a firm, level surface. They can also be driven from one location to another and positioned to resume work without a lot of set-up time.


• Another feature that has become standard on lift machines is a platform extension. This is a rollout platform extending about three feet, with a capacity of 250 pounds. The advantage of extensions is that they overcome the access limitation of scissor lifts. Since scissor lifts normally only lift vertically, the platform extension provides some horizontal reach to extend over obstacles.
  

Disadvantages and solutions:

• Cost Considerations -
  Batteries do wear out and they are costly to replace, hydraulic hoses can deteriorate or have loose fittings resulting in fluid leakage problems and electronic controls can be at the end of their useful life and need replacing.
  A new 20-foot platform height scissor lift lists around will have new features that can make this investment worthwhile such as improved controls, lighter weight aluminum platform decks, re-engineered drive systems that use electric motors rather than hydraulic motors and a hydraulic lift cylinder combined with the hydraulic reservoir. Other advantages to the newly designed scissor lifts include reduced maintenance, significantly extended battery life and less chance for hydraulic leaks since some models have only four hydraulic connections versus the 40 or more on some older machines.
  

Typical Applications：

Construction, industrial, maintenance, distribution, entertainment and institutional users
Warehousing and distribution centers
Hotel, recreation and educational facilities
Construction (commercial buildings and infrastructure)
Mechanical, electrical, utility and painting contractors
Manufacturing and industrial facilities

Newer Scissor lift:

Another benefit of newer scissor lifts is the smaller size of the battery pack installed. Newer machines use lighter but stronger alloys, consolidated operating systems and incorporate more precision bearings and more accurately machined scissor pins. As a result, frictional drag is reduced and machines can operate more efficiently, so smaller battery sizes can be used. Smaller batteries mean the machine has less weight and lower battery replacement costs.

The design innovation that delivers the greatest improvement in the number of duty cycles is the use of direct drive electric motors instead of hydraulic motors. Using direct drive eliminates inefficiencies of pumping hydraulic fluid through hoses to and from the reservoir to the hydraulic motors driving the machine.

Electric drive motors power the wheels more efficiently than hydraulic motors. The efficiency of an electric drive is 65 percent versus hydraulic drive at 30 percent. In other words, scissor lifts with electric drive motors operate at twice the efficiency of machines that use hydraulic motors for their drive function.