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Material Handling System in Flexible Manufacturing
The material handling system (MHS) is a fundamental part of a Flexible manufacturing system since it interconnects the different processes supplying and taking out raw material, workpieces, subproducts, parts and final products. Due to the automated nature of the whole production process, the MHS must respond in concert with timeliness for all requirements of the processes and systems.
The MHS is composed of warehouses, buffers, conveyors, transportation vehícles or systems, part sorters, feeders and manipulators
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A Miniload AS/RS - an example of a material handling system.
Forklift trucks are common in material handling.
Motorcycles stored in specialty push back rack.
OVERHEAD CRANE
An overhead crane, featuring runways, bridge, and hoist in a traditional industrial environment.
Overhead crane at the Skanska precast concrete factory in Hjärup
An overhead crane, commonly called a bridge crane, is a type of crane found in industrial environments. An overhead crane consists of parallel runways with a traveling bridge spanning the gap. A hoist, the lifting component of a crane, travels along the bridge. If the bridge is rigidly supported on two or more legs running on a fixed rail at ground level, the crane is called a gantry crane (USA, ASME B30 series) or a goliath crane (UK, BS 466).
Unlike mobile or construction cranes, overhead cranes are typically used for either manufacturing or maintenance applications, where efficiency or downtime are critical factors.
[edit] Applications
The most common overhead crane use is in the steel industry. At every step of the manufacturing process, until it leaves a factory as a finished product, steel is handled by an overhead crane. Raw materials are poured into a furnace by crane, hot steel is stored for cooling by an overhead crane, the finished coils are lifted and loaded onto trucks and trains by overhead crane, and the fabricator or stamper uses an overhead crane to handle the steel in his factory. The automobile industry uses overhead cranes for handling of raw materials. Smaller workstation cranes handle lighter loads in a work-area, such as CNC mill or saw.
Almost all paper mills use bridge cranes for regular maintenance requiring removal of heavy press rolls and other equipment. The bridge cranes are used in the initial construction of paper machines because they facilitate installation of the heavy cast iron paper drying drums and other massive equipment, some weighing as much as 70 tons.
In many instances the cost of a bridge crane can be largely offset with savings from not renting mobile cranes in the construction of a facility that uses a lot of heavy process equipment.
[edit] Configurations
While sharing major components, overhead cranes are manufactured in a number of configurations based on applications.
[edit] Rotary overhead crane
This type of overhead crane has one end of the bridge mounted on a fixed pivot and the other end carried on an annular track; the bridge traverses the circular area beneath. This offers improvement over a jib crane by making possible a longer reach and eliminating lateral strains on the building walls.[1]
[edit] History
Demag Cranes & Components Corp. was one of the first companies in the world to mass-produce the first steam-powered crane.[2] In 1876 Sampson Moore in England designed and
supplied the first ever electric overhead crane, which was used to hoist guns at the Royal Arsenal in Woolwich, London.[3] Since that time Alliance Machine, now defunct, holds an AISE citation for one of the earliest cranes in the USA market. This crane was in service until approximately 1980, and is now in a museum in Birmingham, Alabama. Over the years important innovations, such as the Weston load brake (which is now rare) and the wire rope hoist (which is still popular), have come and gone. The original hoist contained components mated together in what is now called the built-up style hoist. These built up hoists are used for heavy-duty applications such as steel coil handling and for users desiring long life and better durability. They also provide for easier maintenance. Now many hoists are package hoists, built as one unit in a single housing, generally designed for ten-year life, but the life calculation is based on an industry standard when calculating actual life. See the Hoists Manufacturers Institute site[4] for true life calculation witch is based on load and hours used. In today's modern world for the North American market there are a few governing bodies for the industry. The Overhead Alliance is a group that represents Crane Manufacturers Association of America (CMAA), Hoist Manufacturers Institute (HMI), and Monorail Manufacturers Association (MMA). These product counsels of the Material Handling Industry of America have joined forces to create promotional materials to raise the awareness of the benefits to overhead lifting. The members of this group are marketing representatives of the member companies.
[edit] Early manufacture 1830: First Crane company in Germany Ludwig Stuckenholz company now Demag Cranes &
Components GmbH.[2]
1840: Mass production of overhead cranes starts in Germany
1854: Sampson Moore & Co in Liverpool England patented a new winch mechanism that allowed the lifting of heavier weights (such as naval guns) by an electric motor.[5]
1861: First steam powered overhead crane, installed by John Ramsbottom at the Crewe Railway workshops. Power was transmitted to the crane from a pulley driven by a stationary engine through an endless cotton rope.[2]
1887: Ludwig Stuckenholz company introduces electrical components to overhead cranes determining industry design.
1910: The first Mass production Electric motor hoist started being produced in Germany.
[edit] Gallery
Overhead crane and hoist (device) mounted on a trolley that can be moved across the bridge beam
Example of steam powered overhead crane from 1875, produced by Stuckenholz AG, Wetter am der Ruhr, Germany. Design developed by Rudolf Bredt from an original installation at Crewe railway works[2]
Rotary overhead crane installed in a foundry, ca. 1880[6]
Steam-powered overhead crane from ca. 1890. Three separate, two-cylinder engines provided transverse, longitudinal, and hoisting motion; a feature of the design was the ability to raise or lower the load while in transit.[7]
Derrick
For other uses, see Derrick (disambiguation).
Derrick of Ocean Star Offshore Oil Rig & Museum, Galveston, Texas
A derrick is a lifting device composed of one tower, or guyed mast such as a pole which is hinged freely at the bottom. It is controlled by lines (usually four of them) powered by some means such as man-hauling or motors, so that the pole can move in all four directions. A line runs down and over its botom with a hook on the end, like with a crane. It is commonly used in docks and on board ships. Some large derricks are mounted on dedicated vessels, and are often known as "floating derricks".
The device was named for its resemblance to a type of gallows from which a hangman's noose hangs. The derrick type of gallows in turn got its name from Thomas Derrick, an English executioner from the Elizabethan era.
Contents
[hide]
1 Oil derrick 2 Patent Derrick Systems
o 2.1 Hallen Derrick
o 2.2 Velle Derrick
o 2.3 Stülcken Derrick
3 See also
4 References
5 Further reading
6 External links
[edit] Oil derrick
Main article: Drilling rig
Ornamental oil derricks in Kilgore, Texas
Another kind of derrick is used around oil wells and other drilled holes. This is generally called an oil derrick and is a complex set of machines specifically designed for optimum efficiency, safety and low cost. This is used on some offshore oil and gas rigs.
The centerpiece is the archetypical derrick tower, used for lifting and positioning the drilling string and piping above the well bore, and containing the machinery for turning the drilling bit around in the hole. As the drill string goes deeper into the underlying soil or rock, new piping has to be added to the top of the drill to keep the connection between drill bit and turning machinery intact, to create a filler to keep the hole from caving in, and to create a conduit for the drilling mud. The drilling mud is used to cool the drilling bit and to blow rock debris clear from the drill bit and the bottom of the well. The piping joints sections—usually each about 10 meters (30 ft) long—have threaded ends, so they can be screwed together. The piping is hollow to allow for the mud to be pumped down into the drilling hole, where it flushes out at the drilling bit. The mud then proceeds upwards towards the surface on the outside of the piping, carrying the debris with it.
The derrick also controls the weight on the drilling bit, because the drill bit works at an optimum rate only when it is pushed with a precise degree of pressure relative to the rock beneath it. Too much weight can break the drilling bit, and not enough weight will prolong drilling time. At the start of drilling extra heavy piping collars are used to create enough weight to drill. Since the weight of the pipes above the drill bit will increase the pressure on it as it goes deeper, the
derrick will apply less pressure as piping sections are added. It will eventually lift the nearly entire drill string-and-piping complex to prevent too much weight as the well goes deeper.
[edit] Patent Derrick Systems
[edit] Hallen Derrick
The boom is connected with the lower part of the mast which is shaped like a “Y” or a bipod and therefore it is a single swinging derrick. On the cross trees, two guys are fastened using swivel outriggers which are stayed vertically and horizontally. In order to maintain a good controlling angle between guys and derrick, the outriggers cannot pass the inboard parallel of the centerline. Looking at the illustration, one can easily see that the right outrigger stays in the centerline and the left outrigger has moved outboard. This derrick will lower or heave cargo as both guys are veered or hauled. Three winches, controlled by joystick, are necessary to operate the Hallen Derrick; two for the guys and one for the purchase. To avoid an over-topping or over-swinging limit-switches are used. However, the limits can be modified if a different working range or a special vertical stowage is required. The safe working load (SWL) of the Hallen is between 10 and 80 tonnes. In a Hallen Universal derrick, which has no Hallen D-Frame, the halyard has an extended length since it runs through further blocks on the centerline. The Universal Hallen derrick, replacing the D-frame option, is a kind of traditional topping lift. The Hallen D-Frame is a steel bracket welded on the mast in the centerline. For an observer standing a beam, the frame has a “D”-shape. The D-Frame supersedes the outriggers and provides a good controlling angle on the guys. The Hallen derrick has a good purpose for e.g. containers, logs, steel rail, sawn timber and heavy lifts and doesn't lend itself for small, general cargo. It keeps the deck clear of guy ropes and preventors. Only one winchman is needed and within a few minutes the Hallen is brought into use. It is less expensive than a crane. A disadvantage is the low working range of the Hallen Derrick, it is able to swing 75° from the centerline and can work against a list of up to 15°.
[edit] Velle Derrick
The Velle derrick is quite similar to the Hallen but without use of outriggers. On top of the boom is a T-shaped yoke assembled. Also here, the guys serve for topping and lowering the boom but they are fastened on the yoke with four short, steel-wire hanger-ropes. The ends of the topping and lowering ends of the halyard are secured to half-barrels on one winch. In this way the boom moves in the same speed as the winch veers the topping end of the halyard and hauls the lowering end of the halyard, and vice versa. The slewing ends are also wound on to another half-barrel. For hoisting the cargo, there is a third winch to hoist to cargo on the yoke. Runners decrease swing and rotation of the cargo. A joystick duplex controller steers the Velle derrick.
[edit] Stülcken Derrick
Stülcken heavylift derrick
The patent Stülcken derrick is used for very heavy cargo. It stems from the German shipyard HC Stülcken & Sohn which has been taken over later by neighboring yard Blohm & Voss. This derrick can handle up to 300 tonnes. The Stülcken can be made ready in few minutes, which is a lot faster than a traditional heavy derrick, doesn't require lots of space and is operated by four winches. Between two v-shaped, unstayed Samson-posts is the Stülcken secured. This makes it possible to let the derrick swing through the posts to reach another hatch. For each post is a hoisting winch, a span winch and a lever that is run by one man only. Bearings, swivels, sheaves and the gooseneck can be unattended for up to four years and create only a friction of about 2%. The span tackles are independent and the halyard is endless. With the revolving suspension heads on the posts it takes ten minutes to swing all the way through. In the double-pendulum block type, half of the cargo tackle can be anchored to the base of the boom. In order to double the hook speed, the halyard passes through the purchases since one end is secured which reduces the SWL to its half. Typical dimensions of a 275 tonne Stülcken are: 25.5 m length, 0.97 m diameter, 1.5 m to 3.4 m diameter of posts, 18 m apart the posts (upper end) and 8.4 m apart the posts (lower end). The hook of a full-loaded 275 tonne Stülcken can move 2.3 m per minute. If only one purchase is secured and the derrick is loaded with 137 tonnes the hook gains velocity to 4.6 m per min. Even more speed can be gained when the winch ratios are reduced to 100 tonnes (triple speed) and 68 tonnes (quadruple speed). Detaching the union table the double-pendulum block type of Stülcken is able to swing through which allows the lower blocks to swing freely to each side of the boom. In this way the derrick reaches a vertical position. A bullrope easily pulls the derrick to the other side until the weight of the cargo tips the derrick over. The span tackles now have the weight on the other side. The union table is fixed again and the derrick can start its
work on the other side. There are also Stülcken with single-pendulum blocks. At this type the cargo hook is detached and the lower and upper cargo block are hauled into the center of the Stülcken. To tip the derrick over the gravity is here used again. A derrick helps pump oil in most offshore rigs.
Replica of an oil derrick atop picnic tables at a roadside stop along Interstate 20 west of Tyler, Texas
Carton flow
Carton flow rack
Carton flow is a form of shelving that uses a gravity feed rear load design. Each unit consists of one or more inclined runways. Merchandise is loaded in the rear of each runway. As an item is removed from the front, the item directly behind it slides forward in place of the previous.
Put simply, the main advantage of carton flow rack over static rack or shelving systems is that merchandise remains better organized and easier to find/pick. With carton flow rack, the product is automatically rotated on a first in first out basis. Merchandise is stocked in the rear of the carton flow rack and moves toward the picking station in front on an inclined shelf equipped with specially designed roller track. When a carton is removed from the picking station, the next one in line rolls to the front. Carton flow always keeps items within reach. Inventory is easier to monitor and control since products are fully visible at all times.
Restocking and picking typically offer the greatest opportunity for improving efficiency within order picking operations. With carton flow rack systems labor savings of up to 75% can be realized almost immediately. Because items are picked from the front and stocked from the rear, both functions can be performed without interference and with minimized travel.
In a static storage system such as standard shelving, the stockers and pickers are often doing a lot of unnecessary travel.
[edit] History
Lansing Peter Shield, President of Grand Union Co., applied for patents for the original gravity-feed rear load design using Unistrut and Nylon strips in 1945 (later approved in 1948). The unit consisted of several inclined runways. The device was driven by gravity. A stockman would place merchandise in the rear of each runway and, as a shopper selected an item, the item behind it would slide forward in place of the previous one
Grand Union formed a company called Food-O-Mat to sell the carton flow system, and made Gardner Hinckley the President. Gauer Metal Products, Inc manufactured the carton flow units for Grand Union/Food-O-Mat When Lansing Shield died of a heart attack, Thomas Butler was appointed the new president. Butler had no interest in continuing to use carton flow units in Grand Union Supermarkets so Food-O-Mat went off on its own to sell the product with Gauer Metal Products, Inc as its manufacturer.
[edit] Carton flow today
The carton flow design has gone through countless changes over the years, and has now evolved to full shelving units. These units consist of polyethylene or aluminum roller runways and can be both stand alone racks or can be installed into pallet racks. Conveyor systems are sometimes used as an alternate option to carton flow shelving.
Forklift truck
A US airman operating a Hyster forklift
A forklift truck (also called a lift truck, a fork truck, a forklift, or a tow-motor) is a powered industrial truck used to lift and transport materials. The modern forklift was developed in the 1920s by various companies including the transmission manufacturing company Clark and the hoist company Yale & Towne Manufacturing.[1] The forklift has since become an indispensable piece of equipment in manufacturing and warehousing operations.
[edit] History
Toyota's first lift truck
The middle nineteenth century through the early twentieth century saw the developments that led to today's modern forklifts. The Pennsylvania Railroad in 1906 introduced battery powered platform trucks for moving luggage at their Altoona, Pennsylvania train station. World War I saw the development of different types of material handling equipment in the United Kingdom by Ransomes, Sims and Jeffries of Ipswich. This was in part due to the labor shortages caused by the war. In 1917 Clark in the United States began developing and using powered tractor and
powered lift tractors in their factories. In 1919 the Towmotor Company and Yale & Towne Manufacturing in 1920 entered the lift truck market in the United States.[2]
Continuing development and expanded use of the forklift continued through the 1920s and 1930s. World War II, like World War I before, spurred the use of forklift trucks in the war effort. Following the war, more efficient methods for storing products in warehouses were being implemented. Warehouses needed more maneuverable forklift trucks that could reach greater heights. New forklift models were made that filled this need.[3] In 1956 Toyota introduced its first lift truck model, the Model LA, in Japan and sold its first forklift in the United States in 1967.[4]
[edit] Design types
Forklift classes and lift codes
A truck mounted forklift.
A Raymond reach truck. Note the pantograph allowing the extension of the forks in tight aisles. This electric machine weighs over 7000lbs and can lift 4000lbs to 24 feet in the air.
A photo realistic illustration of a sitdown rider 4-wheel electric forklift truck.
The following is a list, in no particular order, of the more common lift truck types:
Hand pallet truck - no power system of any kind Walkie low lift truck[5] - powered pallet truck, usually Electrically Powered[citation needed]
Rider low lift truck[5] - usually Electrically Powered
Towing tractor[5] - Maybe Internal Combustion Engine or Electric Powered
Walkie stacker[5] - usually Electrically Powered
Rider stacker[5] - usually Electrically Powered
Reach truck [5]- Variant on a Rider Stacker forklift, designed for small aisles, usually Electrically Powered, named because the forks can extend to reach the load. There are two variants,
moving carriage, which are common in North America, and moving mast which are common in the rest of the world, and generally regarded as safer[citation needed]
Electric Counterbalanced truck[5]- comes in Stand on End Control, Stand on Center Control, and Sit Down Center Control, which is the most numerous[citation needed]
Internal Combustion Engine Powered Counterbalanced Forklift[5]- comes in Stand on End Control, Stand on Center Control, and Sit Down Center Control, which is the most numerous. Engines may be diesel, kerosene, gasoline, natural gas, butane, or propane fueled, and may be either Two Stroke Spark Ignition, Four Stroke Spark Ignition (common), Two Stroke Compression Ignition, and Four Stroke Compression Ignition (common). North American Engines come with advanced emission control systems. Forklifts built in countries like Iran or Russia will typically have no emission control systems.[citation needed]
Electric Forklifts - Powered by lead-acid batteries, several types of forklifts are electric: cushion tire forklifts, scissor lifts, order pickers, stackers, reach trucks and pallet jacks. Electric forklifts are primarily used indoors on flat, even surfaces. Electric forklift batteries last 6 consecutive hours or throughout an 8-hour shift with 2-3 breaks. Batteries prevent the emission of harmful fumes and are recommended for facilities in food-processing and healthcare sectors.
Sideloader[5] - comes in Stand on End Control, and Sit Down End Control, which is the most numerous. It may be Electrically Powered, or have an Internal Combustion Engine. Engines may be diesel, kerosene, gasoline, natural gas, butane, or propane fueled, and may be either Two Stroke Spark Ignition, Four Stroke Spark Ignition (common), Two Stroke Compression Ignition, and Four Stroke Compression Ignition (common). North American Engines come with advanced emission control systems. Forklifts built in countries like Iran or Russia will typically have no emission control systems. Some Sideloaders have Hybrid drivetrains.[citation needed]
Telescopic handler - comes in Stand on Center Control, and Sit Down Center Control, which is the most numerous. Usually has an Internal Combustion Engine. Engines are almost always diesel, but sometimes operate on kerosene, and sometimes use propane injection as a power boost. Some old units are Two Stroke Compression Ignition, most are Four Stroke Compression Ignition (common). North American Engines come with advanced emission control systems. Forklifts built in countries like Iran or Russia will typically have no emission control systems. Some Telescopic handlers have Hybrid drivetrains.[citation needed]
Walkie Order Picking truck[5] - usually Electrically Powered
Rider Order Picking truck[5] - commonly called an "Order Picker"; like a small Reach Truck, except the operator rides in a cage welded to the fork carriage, while wearing a specially designed safety harness to prevent falls. A special toothed grab holds the pallet to the forks. The operator hand transfers the load onto the pallet one article at a time. This is an efficient way of picking less than pallet load shipments, and is popular for use in large distribution centers.
Articulated Very Narrow Aisle Counterbalanced trucks - sometimes called "Flexi or Bendi Trucks" after two of the largest manufacturers. Comes in Stand on Center Control, and Sit Down Center Control, which is the most numerous. May have an Internal Combustion Engine or an Electric Motor. Electric Motors are most common. Engines may be diesel, kerosene, gasoline, natural gas, butane, or propane fueled, and may be either Two Stroke Spark Ignition, Four Stroke Spark Ignition (common), Two Stroke Compression Ignition, and Four Stroke Compression Ignition
(common). North American Engines come with advanced emission control systems. Forklifts built in countries like Iran or Russia will typically have no emission control systems. Some units have Hybrid drivetrains.[citation needed]
Guided Very Narrow Aisle truck - A counterbalance type Sit Down Rider Electric Forklift fitted with a specialized mast assembly. The Mast is capable of rotating 90 degrees, and the forks can then advance like on a reach mechanism, to pick full pallets. Because the forklift doesn't not have to turn, the aisles can be exceptionally narrow, and if wire guidance is fitted in the floor of the building the machine can almost work on its own. Masts on this type of machine tend to be very high. The higher the racking that can be installed, the higher the density the storage can reach. This sort of storage system is popular in cities where land prices are really high, as by building the racking up to three times higher than normal and using these machines, it is possible to stock an incredible amount of material in what appears to be a small space.[citation needed]
Guided Very Narrow Aisle Order Picking truck - A counterbalance type Order Picking Truck similar to the Guided Very Narrow Aisle truck, except that the operator and the controls which operate the machine are in a cage welded to the mast. The operator of course wears a restraint system to protect him against falls. Otherwise the description is the same as Guided Very Narrow Aisle truck.[citation needed]
Truck Mounted Forklift / Sod Loader - comes in Sit Down Center Control. Usually has an Internal Combustion Engine. Engines are almost always diesel, but sometimes operate on kerosene, and sometimes use propane injection as a power boost. Some old units are Two Stroke Compression Ignition, most are Four Stroke Compression Ignition (common). North American Engines come with advanced emission control systems. Forklifts built in countries like Iran or Russia will typically have no emission control systems. Some Telescopic handlers have Hybrid drivetrains.[citation needed]
[edit] Specialty trucks
At the other end of the spectrum from the counterbalanced forklift trucks are more 'high end' specialty trucks:
Articulated Counterbalance Trucks
These are, unlike most lift trucks, front wheel steer, and are a hybrid VNA (Very Narrow Aisle) truck designed to be both able to offload trailers and place the load in narrow aisle racking. Increasingly these trucks are able to compete in terms of pallet storage density, lift heights and pallet throughput with Guided Very Narrow Aisle trucks, while also being capable of loading trucks, which VNA units are incapable of doing.[citation needed]
Guided Very Narrow Aisle Trucks
These are rail or wire guided and available with lift heights up to 40' non top-tied and 98' top-tied. Two forms are available; 'man-down' and 'man-riser' where the operator elevates with the load for increased visibility or for multilevel 'break bulk' order picking. This type of truck, unlike Articulated Narrow Aisle Trucks, requires a high standard of floor flatness.[citation needed]
Omni-directional Trucks
Omni-directional technology (such as mecanum wheels) can allow a forklift truck to move forward, diagonally and laterally, or in any direction on a surface. Omni-directional wheel system is able to rotate the truck 360 degrees in its own footprint or strafe sideways without turning the truck cabin. One example is the Airtrax Sidewinder. This forklift truck has also made an appearance in the TV -series called 'Mythbusters'.
UL 558 Safety Rated Trucks
In North America, some internal combustion powered industrial vehicles carry Underwriters Laboratories ratings that are part of UL 558. Industrial trucks that are considered "safety" carry the designations GS (Gasoline Safety) for gasoline powered, DS (Diesel Safety) for diesel powered, LPS (Liquid Propane Safety) for liquified propane or GS/LPS for a dual fuel gasoline/liquified propane powered truck.[6]
UL 558 is a two stage Safety Standard. The basic standard, which is G, D, LP, and G/LP is what Underwriter's Laboratories considers the bare minimum required for a lift truck. This is a voluntary standard, and there is no requirement in North America at least by any Government Agency for manufacturers to meet this standard.
The slightly more stringent GS, DS, LPS, and GP/LPS, or Safety standard does provide some minimal protection, however it is extremely minimal. In the past Underwriter's Laboratory offered specialty EX and DX safety certifications. If you require higher levels of protection you must contact your local Underwriter's Laboratory Office and check ask them what the correct safety standard is for your workplace.[citation needed]
UL 583 Safety Rated Trucks
UL 583 is the Electric equivalent of UL 558. As with UL 558 it is a two stage standard.[citation needed]
Explosion proof trucks "EX RATED"
These are for operation in potentially explosive atmospheres found in chemical, petrochemical, pharmaceutical, food and drink, logistics or other industries handling flammable material. Commonly referred to as Pyroban trucks in Europe, they must meet the requirements of the ATEX 94/9/EC Directive if used in Zone 1, 2, 21 or 22 areas and be maintained accordingly.[citation needed]
U.S. Military 10K-AT "Adverse Terrain"
[edit] Automated forklift trucks
In order to decrease work wages, reduce operational cost and improve productivity, automated forklifts have also been developed.[7][8] Automated forklifts are also called forked automated guided vehicles and are already available from a growing number of suppliers.[9]
[edit] Counterbalanced forklift components
A typical counterbalanced forklift contains the following components:[10]
Image of an electric forklift with component descriptions
Truck Frame - is the base of the machine to which the mast, axles, wheels, counterweight, overhead guard and power source are attached. The frame may have fuel and hydraulic fluid tanks constructed as part of the frame assembly.
Counterweight - is a mass attached to the rear of the forklift truck frame. The purpose of the counterweight is to counterbalance the load being lifted. In an electric forklift the large lead-acid battery itself may serve as part of the counterweight.
Cab - is the area that contains a seat for the operator along with the control pedals, steering wheel, levers, switches and a dashboard containing operator readouts. The cab area may be open air or enclosed, but it is covered by the cage-like overhead guard assembly. The 'Cab' can also be equipped with a Cab Heater for cold climate countries.
Overhead Guard - is a metal roof supported by posts at each corner of the cab that helps protect the operator from any falling objects. On some forklifts, the overhead guard is an integrated part of the frame assembly.
Power Source - may consist of an internal combustion engine that can be powered by LP gas, CNG gas, gasoline or diesel fuel. Electric forklifts are powered by either a battery or fuel cells that provides power to the electric motors. The electric motors used on a forklift may be either DC or AC types.
Tilt Cylinders - are hydraulic cylinders that are mounted to the truck frame and the mast. The tilt cylinders pivot the mast to assist in engaging a load.
Mast - is the vertical assembly that does the work of raising and lowering the load. It is made up of interlocking rails that also provide lateral stability. The interlocking rails may either have rollers or bushings as guides. The mast is driven hydraulically, and operated by one or more hydraulic cylinders directly or using chains from the cylinder/s. It may be mounted to the front axle or the frame of the forklift.
Carriage - is the component to which the forks or other attachments mount. It is mounted into and moves up and down the mast rails by means of chains or by being directly attached to the hydraulic cylinder. Like the mast, the carriage may have either rollers or bushings to guide it in the interlocking mast rails.
Load Back Rest - is a rack-like extension that is either bolted or welded to the carriage in order to prevent the load from shifting backward when the carriage is lifted to full height.
Attachments - may consist of forks or tines that are the L-shaped members that engage the load. A variety of other types of material handling attachments are available. Some attachments include sideshifters, slipsheet attachments, carton clamps, multipurpose clamps, rotators, fork positioners, carpet poles, pole handlers, container handlers and roll clamps.
[edit] Attachments
Below is a list of common forklift attachments:[11]
Dimensioning Devices-fork truck mounted dimensioning systems provide dimensions for the cargo to facilitate truck trailer space utilization and to support warehouse automation systems. The systems normally communicate the dimensions via 802.11 radios. NTEP certified dimensioning devices are available to support commercial activities that bill based on volume.
Sideshifter - is a hydraulic attachment that allows the operator to move the tines (forks) and backrest laterally. This allows easier placement of a load without having to reposition the truck.[12]
Rotator - To aid the handling of skids that may have become excessively tilted and other specialty material handling needs some forklifts are fitted with an attachment that allows the tines to be rotated. This type of attachment may also be used for dumping containers for quick unloading.
Fork Positioner - is a hydraulic attachment that moves the tines (forks) together or apart. This removes the need for the operator to manually adjust the tines for different sized loads.
Roll and Barrel Clamp Attachment - A mechanical or hydraulic attachment used to squeeze the item to be moved. It is used for handling barrels, kegs, or paper rolls. This type of attachment may also have a rotate function. The rotate function would help an operator to insert a vertically stored paper into the horizontal intake of a printing press for example.
Pole Attachments - In some locations, such as carpet warehouses, a long metal pole is used instead of forks to lift carpet rolls. Similar devices, though much larger, are used to pick up metal coils.
Carton and Multipurpose Clamp Attachments - are hydraulic attachments that allow the operator to open and close around a load, squeezing it to pick it up. Products like cartons, boxes and bales can be moved with this type attachment. With these attachments in use, the forklift truck is sometimes referred to as a clamp truck.
Slip Sheet Attachment (Push - Pull) - is a hydraulic attachment that reaches forward, clamps onto a slip sheet and draws the slip sheet onto wide and thin metal forks for transport. The attachment will push the slip sheet and load off the forks for placement.
Drum Handler Attachment - is a mechanical attachment that slides onto the tines (forks). It usually has a spring-loaded jaw that grips the top lip edge of a drum for transport. Another type grabs around the drum in a manner similar to the roll or barrel attachments.
Man Basket - a lift platform that slides onto the tines (forks) and is meant for hoisting workers. The man basket has railings to keep the person from falling and brackets for attaching a safety harness. Also, a stap or chain is used to attach the man basket to the carriage of the forklift.
Telescopic Forks - are hydraulic attachments that allow the operator to operate in warehouse design for "double-deep stacking", which means that two pallet shelves are placed behind each other without any aisle between them.
Scales -Fork truck mounted scales enable operators to efficiently weigh the pallets they handle without interrupting their workflow by travelling to a platform scale. Scales are available that provide legal-for-trade weights for operations that involve billing by weight. They are easily retrofitted to the truck by hanging on the carriage in the same manner as forks hang on the truck.
Any attachment on a forklift will reduce its nominal load rating, which is computed with a stock fork carriage and forks. The actual load rating may be significantly lower.
[edit] Replacing or adding attachments
It's possible to replace an existing attachment or add one to a lift that doesn't already have one. Considerations include forklift type, capacity, carriage type, and number of hydraulic functions (that power the attachment features). As mentioned in the preceding section, replacing or adding an attachment may reduce (down-rate) the safe lifting capacity of the forklift truck (See also General operations, below).
Forklift attachment manufacturers offer on-line calculators to estimate the safe lifting capacity when using a particular attachment, but only the forklift truck manufacturer can give accurate lifting capacities. Before installing any attachment, you should contact your local authorized dealer of your forklift brand, and ask them to begin re-rating your lift according to the
attachment you want to install. Once re-rated you should receive a new factory authorized specification plate to replace the original currently found on your lift.
[edit] Adding hydraulic functions
In the context of attachments, a hydraulic function consists of a valve on the forklift with a lever near the operator that provides two passages of pressurized hydraulic oil to power the attachment features. Sometimes an attachment has more features than your forklift has hydraulic functions, and one or more need to be added.
There are many ways of adding hydraulic functions (also known as adding a valve). The forklift manufacturer makes valves and hose routing accessories, but the parts and labor to install can be prohibitively expensive. Other ways include adding a solenoid valve in conjunction with a hose or cable reel that diverts oil flow from an existing function. However, hose and cable reels can block the operator's view and are problematic, easily damaged. The Ditto Valve kit uses a solenoid valve and special HydWire hoses, in which the wire reinforcing braid doubles as an electrical conduit. These hoses replace those already on the forklift, nesting in the original reeving, keeping it safe from damage and out of the operators field of vision.[13]
[edit] Forklift control and capabilities
A Forklifts hydraulics are controlled with either levers directly manipulating the hydraulic valves, or by electrically controlled actuators, using smaller "finger" levers for control. the latter allows forklift designers more freedom in ergonomical design.
A straight mast container handler at Haikou Xiuying Port, Hainan, China
Forklift trucks are available in many variations and load capacities. In a typical warehouse setting most forklifts used have load capacities between one to five tons. Larger machines, up to 50 tons lift capacity are used for lifting heavier loads, including loaded shipping containers.[14]
a typical load capacity chart
In addition to a control to raise and lower the forks (also known as blades or tines), the operator can tilt the mast to compensate for a load's tendency to angle the blades toward the ground and risk slipping off the forks. Tilt also provides a limited ability to operate on non-level ground. Skilled forklift operators annually compete in obstacle and timed challenges at regional forklift rodeos.
[edit] General operations
A forklift transporting a pallet of potted plants.
Forklifts are rated for loads at a specified maximum weight and a specified forward center of gravity. This information is located on a nameplate provided by the manufacturer, and loads must not exceed these specifications. In many jurisdictions it is illegal to remove or tamper with the nameplate without the permission of the forklift manufacturer.
An important aspect of forklift operation is that most have rear-wheel steering. While this increases maneuverability in tight cornering situations, it differs from a driver’s traditional experience with other wheeled vehicles. While steering, as there is no caster action, it is unnecessary to apply steering force to maintain a constant rate of turn.
Another critical characteristic of the forklift is its instability. The forklift and load must be considered a unit with a continually varying center of gravity with every movement of the load. A forklift must never negotiate a turn at speed with a raised load, where centrifugal and
gravitational forces may combine to cause a disastrous tip-over accident. The forklift are designed with a load limit for the forks which is decreased with fork elevation and undercutting of the load (i.e. load does not butt against the fork "L"). A loading plate for loading reference is usually located on the forklift. A forklift should not be used as a personnel lift without the fitting of specific safety equipment, such as a "cherry picker" or "cage".
[edit] Forklift use in warehouse and distribution centers
Forklifts are a critical element of warehouses and distribution centers. It’s imperative that these structures be designed to accommodate their efficient and safe movement.
In the case of Drive-In/Drive-Thru Racking, a forklift needs to travel inside a storage bay that is multiple pallet positions deep to place or retrieve a pallet. Oftentimes, forklift drivers are guided into the bay through guide rails on the floor and the pallet is placed on cantilevered arms or rails. These maneuvers require well-trained operators. Since every pallet requires the truck to enter the storage structure, damage is more common than with other types of storage. In designing a drive-in system, dimensions of the fork truck, including overall width and mast width, must be carefully considered.[15]
[edit] Lift truck associations and organizations
There are many national as well as continental associations related to the industrial truck industry. Some of the major organizations are listed as:
Industrial Truck Association (ITA) (North America)[16]
Material Handling Equipment Distributors Association (MHEDA) (North America)[17]
Fédération Européenne de la Manutention - European Federation of Materials Handling (FEM)[18]
Fork Lift Truck Association (FLTA) (UK)[19]
British Industrial Truck Association (BITA)[20]
Japan Industrial Vehicles Association (JIVA)[21]
Korean Construction Equipment Manufacturers Association (KOCEMA)[22]
There are many significant contacts among these organizations and they have established joint statistical and engineering programs. One program is the World Industrial Trucks Statistics (WITS) which is published every month to the association memberships. The statistics are separated by area (continent), country and class of machine. While the statistics are generic, and do not count production from most of the smaller manufacturers, the information is significant for its depth. These contacts have brought to a common definition of a Class System which all the major manufacturers adhere to.
[edit] Forklift safety organizations
Near miss unsafe work practice example: Forklift tipping over from excessive weight being picked up.
Near miss unsafe work practice example: Forklift being narrowly prevented from tipping over by having an extra worker hop on the back of the forflift as a counterweight to prevent having the forklift and the load tip over.
[edit] Standards
Forklift safety is subject to a variety of standards world wide. The most important standard is the ANSI B56—of which stewardship has now been passed from the American National Standards Institute (ANSI) to the Industrial Truck Standards Development Foundation after multi-year negotiations. ITSDF is a non-profit organization whose only purpose is the promulgation and modernization of the B56 standard.[23]
Other standards have been implemented in the United States by the Occupational Safety and Health Administration (OSHA) and in the United Kingdom by the Health and Safety Executive.[24] In many countries forklift truck operators must be trained and certified to operate forklift trucks. Certification may be required for each individual class of lift that an operator would use.
[edit] Forklift Training in the United Kingdom
In the UK, the Provision and Use of Work Equipment Regulations (PUWER) state that operators of fork lift trucks must be adequately trained in their operation, but the nature of this training is not specified. Third party organisations have developed de-facto 'best practice' standards for forklift training, commonly referred to in the UK as a 'forklift licence', but such training is not a legal requirement as is commonly believed.[25] Organised training however helps to demonstrate that an employer has taken steps to ensure its 'duty of care' in the unfortunate event of an accident. The details below represent the de-facto standards proscribed by training organisations.
In the UK, Forklift Training is carried out by a number of different organisations, which all Forklift Instructors must be registered with at least one of them. Although R.T.I.T.B. operators are registered on a database which has to be renewed a 3 yearly basis, the amount of time determined between refresher courses is subject to the H&S Executive, Insurance companies or company policies. The H&S Executive (HSG136 Workplace Transport Safety) does recommend re-training/testing every 3 to 5 years[citation needed].
United Kingdom Forklift Instructors can be registered to one of the following, though registration is not compulsory to instruct:
RTITB
Independent Training Standards Scheme and Register (ITSSAR)
Association of Industrial Truck Trainers (AITT)
National Plant Operators Registration Scheme (NPORS)
CITB-ConstructionSkills
Lantra - Sector Skills Council for the environmental and land-based sector
There are various different training companies across the UK that can provide training on-site and off-site, these can be independent instructors or part of a training company. There are also various training centres across the United Kingdom that can provide individuals not already trained to use a Forklift Truck to help gain a certificate of competence.
In the United Kingdom training falls into four different categories:
REFRESHER - People who have gained a Forklift Training Certificate and need to be brought up to date with new laws and/or regulations.
CONVERSION - People who have been trained on a type of truck recently, and need to start using a different type.
SEMI-EXPERIENCED - People who are competent on a forklift truck, but have never been certificated.
NOVICE - Never been on a Forklift Truck before and never been certificated.
The courses can last for 1 day for a Refresher or a Conversion course, to 5 days for a Novice course. It is recommended in the Approved Code of Practice (ACoP) for Lift Truck Operator Training that United Kingdom Forklift Instructors train a maximum of three people per session; this does not include classroom work.
[edit] Manufacturer's worldwide ranking
Every year Modern Materials publishes a Top 20 Global Ranking of Forklift Manufacturers by sales in dollars.[26] A modified copy of the report is below in a sortable table.
Rank Company Name2008 Rank
2009 RevenueNorth American
BrandsWorld
HeadquartersCountry
1 Toyota Industries 1 $4,600,000,000Toyota, BT, Raymond
Aichi Japan
2 KION Group 2 $4,100,000,000VOLTAS, Linde, STILL, OM, Baoli
Wiesbaden Germany
3 Jungheinrich Lift Truck 3 $2,300,000,000 Jungheinrich Hamburg Germany
Rank Company Name2008 Rank
2009 RevenueNorth American
BrandsWorld
HeadquartersCountry
Corp.
4Crown Equipment Corporation
5 $1,600,000,000 Crown, HamechNew Bremen, Ohio
USA
5 NACCO Industries, Inc. 4 $1,500,000,000 Hyster, Yale Cleveland, Ohio USA
6Mitsubishi Caterpillar Forklift America Inc.
6 $920,000,000 Mitsubishi, CAT Sagamihara Japan
7 Komatsu Utility Co. 8 $750,000,000 Komatsu, Tusk Tokyo Japan
8 Anhui Forklift Group 9 $668,000,000 Heli Hefei, Anhui China
9 Nissan Forklift Corp. 7 $624,000,000Nissan, Barrett, Atlet
Tokyo Japan
10 TCM Corp. 10 $593,000,000 TCM Osaka Japan
11 Nippon Yusoki Co. 11 $559,000,000Not available in N. A.
Nagaokakyo, Kyoto
Japan
12 Doosan Infracore 15 $418,000,000 Doosan SeoulSouth Korea
13Clark Material Handling Company
12 $405,000,000 Clark SeoulSouth Korea
14 Manitou 13 $296,000,000 Manitou Ancenis France
15Zhejiang Hangcha Engineering Machinery Co.
14 $251,000,000 HC Hangzhou China
16 Hyundai Heavy Industries 16 $237,000,000 Hyundai UlsanSouth Korea
17 Tailift 18 $100,000,000 Tailift, Worldlift Taichung Taiwan
18 Combilift 19 $98,000,000 Combilift Monaghan Ireland
19 Hytsu N/A $86,000,000 Hytsu Shanghai China
Rank Company Name2008 Rank
2009 RevenueNorth American
BrandsWorld
HeadquartersCountry
20 Hubtex 20 $60,000,000 Hubtex Fulda Germany
Mezzanine
View of the ground floor of the Glaspaleis from the mezzanine
View of the mezzanine in the lobby of the former Capitol Cinema, Ottawa, Canada
A structural steel mezzanine used for industrial storage.
Bilbao Metro station's mezzanine.
In architecture, a mezzanine or entresol is an intermediate floor between main floors of a building, and therefore typically not counted among the overall floors of a building. Often, a mezzanine is low-ceilinged and projects in the form of a balcony. The term is also used for the lowest balcony in a theatre, or for the first few rows of seats in that balcony. The word mezzanine comes from the Italian word mezzano, meaning "middle".[1]
Contents
[hide]
1 Overview o 1.1 Industrial mezzanines
2 References
3 External links
[edit] Overview
The mezzanine floor often projects itself from the walls and does not completely close the view of the ceiling from the floor immediately below. In short, a mezzanine floor and the floor below it share the same ceiling. Mezzanine floors are often located between the ground floor and the first floor but it is not unusual to have mezzanine floors in the upper floors of a building.
In Palladian architecture the mezzanine is a low upper floor, usually for servants and/or storage. In stadiums, the "mezzanine" level is a term often used for premium or "club level" seating, typically just a few rows deep and hanging from the upper tier, affording an unobstructed view of the playing field.
In transit stations, a mezzanine level is often encountered between the station's entry elevation and the platform level, where the service is boarded. This may contain the area where fares are paid, or provide access to different service platforms. The term is used particularly where an open concept of station allows the platforms to be viewed from that level.
[edit] Industrial mezzanines
In industrial applications, mezzanine floor systems are semi-permanent floor systems typically installed within buildings, built between two permanent original stories. These structures are usually free standing and in most cases can be dismantled and relocated. Commercially sold mezzanine structures are generally constructed of three main materials; steel, aluminum, and fiberglass. The decking or flooring of a mezzanine will vary by application but is generally composed of b-deck underlayment and wood product finished floor or a heavy duty steel, aluminum or fiberglass grating.
The mezzanine is often used in shops and similar spaces for storage of tools or materials. The high roof of the shop is ideal for a mezzanine, and offices can be put either below or above it. Mezzanines are frequently used in industrial operations such as warehousing, distribution or manufacturing. These facilities have high ceilings, allowing unused space to be utilized within the vertical cube. Industrial mezzanine structures are typically either structural, roll formed, rack-supported, or shelf-supported, allowing high density storage within the mezzanine structure.
Warehouse
Old warehouses in Amsterdam, Netherlands
Inside Green Logistics Co., Kotka, Finland. The image shows goods loaded on pallets to the left of the aisle, and stacked pallets with no loads to the right of the aisle.
A warehouse is a commercial building for storage of goods. Warehouses are used by manufacturers, importers, exporters, wholesalers, transport businesses, customs, etc. They are usually large plain buildings in industrial areas of cities and towns and villages. They usually have loading docks to load and unload goods from trucks. Sometimes warehouses are designed for the loading and unloading of goods directly from railways, airports, or seaports. They often have cranes and forklifts for moving goods, which are usually placed on ISO standard pallets loaded into pallet racks. Stored goods can include any raw materials, packing materials, spare parts, components, or finished goods associated with agriculture, manufacturing, or commerce.
[edit] Warehouse function
India House, Manchester.
Watts Warehouse.
Merchants Warehouses in Castlefield.
See also: Manchester cotton warehouses
Historically warehouses were a dominant part of the urban landscape used from the start of the Industrial Revolution through the 19th century and into the twentieth century: the building remained when their original usage had changed. There are four identifiable types of warehouses.[1] The cotton industry was co-terminus with the development of the warehouse, and all five types were represented in Manchester, United Kingdom. Warehouses in Manchester were often lavishly decorated juxtaposing with the modern view of warehouses which are assumed to be standard industrial buildings.[2]
[edit] Display of Goods for Sale
These displayed goods for the home trade. This would be finished goods- such as the latest cotton blouses or fashion items. There street frontage was impressive, so they took the styles of Italianate Palazzos.
Richard Cobden's construction in Mosley Street was the first palazzo warehouse. There were already seven warehouses on Portland Street when they commenced building the elaborate Watts Warehouse of 1855,[1][3] but four more were opened before it was finished. It was this type of warehouse that inspired the Germans in Duesseldorf and Muenchen to name their prestigious departmental stores, 'Warenhausen'.
[edit] Overseas Warehouses
These catered for the overseas trade. They became the meeting places for overseas wholesale buyers where printed and plain could be discussed and ordered.[1] Trade in cloth in Manchester was conducted by many nationalities.
Behrens Warehouse is on the corner of Oxford Street and Portland Street. It was built for Louis Behrens & Son by P Nunn in 1860. It is a four storey predominantly red brick build with 23 bays along Portland Street and 9 along Oxford Street.[3] The Behrens family were prominent in banking and in the social life of the German Community in Manchester. [4] [5]
[edit] Packing Warehouses
The main purpose of a packing warehouses was the picking, checking, labelling and packing of goods for export.[1] The packing warehouses: Asia House, India House and Velvet House along Whitworth Street were some of the tallest buildings of their time.
Warehouse storage purpose is to provide provisions for easy access facilities. Security systems with closely monitored 24-hour CCTV surveillance, infrared recording and on-ground security is provided for safety purposes. Climate control facility is also catered for preserving required objects.
[edit] Railway Warehouses
Warehouses were built close to the major stations in railway hubs. The first railway warehouse to be built was opposite the passenger platform at the terminus of the Liverpool and Manchester Railway. There was an important group of warehouses around London Road station (now Piccadilly station).In the 1890s the Great Northern Railway Company’s warehouse was completed on Deansgate: this was the last major railway warehouse to be built.[1]
London Warehouse Picadilly.
this was one of four warehouses built by the Manchester, Sheffield and Lincolnshire Railway in about 1865 to service the new London Road Station. It had its own branch to the Ashton Canal. This warehouse was built of brick with stone detailing. It had cast iron columns with wrought iron beams. [6]
[edit] Canal WarehousesFurther information: Canal warehouse
All these warehouse types can trace their origins back to the canal warehouses which were used for trans-shipment and storage. Castlefield warehouses are of this type- and important as they were built at the terminus of the Bridgewater Canal in 1761.
[edit] Storage and shipping systems
19th century warehouses in Gloucester docks in the United Kingdom, originally used to store imported corn
So-called Sust, a Middle Ages type of warehouse, in Horgen, Switzerland
Some of the most common warehouse storage systems are:
Pallet racking including selective, drive-in, drive-thru, double-deep, pushback, and gravity flow Mezzanine including structural, roll formed, racks
Vertical Lift Modules
Horizontal Carousels
Vertical Carousels
A piece pick, also known as broken case pick, split-case pick, each pick, over-pack or pick/pack, is a type of order selection process where product is picked and handled in individual units and placed in an outer carton, tote or other container before shipping. Catalog companies and internet retailers are examples of predominantly piece-pick operations. Their customers rarely order in pallet or case quantities; instead, they typically order just one or two pieces of one or two items.
According to "PICK THIS!," several elements make up the piece-pick system. They include the order, the picker, the pick module, the pick area, handling equipment, the container, the pick method used and the information technology used.[7]
Material direction and tracking in a warehouse can be coordinated by a Warehouse Management System (WMS), a database driven computer program. Logistics personnel use the WMS to improve warehouse efficiency by directing pathways and to maintain accurate inventory by recording warehouse transactions.
[edit] Automation and optimization
Automatic storage warehouse for small parts
Some warehouses are completely automated, and require only operators to work and handle all the task. Pallets and product move on a system of automated conveyors, cranes and automated storage and retrieval systems coordinated by programmable logic controllers and computers running logistics automation software. These systems are often installed in refrigerated warehouses where temperatures are kept very cold to keep product from spoiling, especially in electronics warehouse where they require specific temperature to avoid damaging the parts, and also where land is expensive, as automated storage systems can use vertical space efficiently. These high-bay storage areas are often more than 10 meters (33 feet) high, with some over 20 meters (65 feet) high. Automated storage systems can be built up to 40m high.
For a warehouse to function efficiently, the facility must be properly slotted. Slotting addresses which storage medium a product is picked from (pallet rack or carton flow), and how they are picked (pick-to-light, pick-to-voice, or pick-to-paper). With a proper slotting plan, a warehouse can improve its inventory rotation requirements—such as first in, first out (FIFO) and last in, first out (LIFO)—control labor costs and increase productivity.[8]
[edit] Modern trends
Aisle with pallets on storage racks
Traditional warehousing has declined since the last decades of the 20th century, with the gradual introduction of Just In Time (JIT) techniques. The JIT system promotes product delivery directly from suppliers to consumer without the use of warehouses. However, with the gradual implementation of offshore outsourcing and offshoring in about the same time period, the distance between the manufacturer and the retailer (or the parts manufacturer and the industrial plant) grew considerably in many domains, necessitating at least one warehouse per country or per region in any typical supply chain for a given range of products.
Recent retailing trends have led to the development of warehouse-style retail stores. These high-ceiling buildings display retail goods on tall, heavy duty industrial racks rather than conventional retail shelving. Typically, items ready for sale are on the bottom of the racks, and crated or palletized inventory is in the upper rack. Essentially, the same building serves as both warehouse and retail store.
Another trend relates to Vendor Managed Inventory (VMI). This gives the vendor the control to maintain the level of stock in the store. This method has its own issue that the vendor gains access to the warehouse.
Large exporters/manufacturers use warehouses as distribution points for developing retail outlets in a particular region or country. This concept reduces end cost to the consumer and enhances the production sale ratio.
Cross docking is a specialized type of distribution center (DC) in that little or no inventory is stored and product is received, processed (if needed) and shipped within a short timeframe. As in warehousing, there are different types of cross docks.
Reverse logistics is another type of warehousing that has gained attention in our "green-conscious" world. The term refers to items that are going from the end user back to the distributor or manufacturer.
[edit] Cool warehouses and cold storage
Cold storage preserves agricultural products. Refrigerated storage helps in eliminating sprouting, rotting and insect damage. Edible products are generally not stored for more than one year. Several perishable products require a storage temperature as low as -25°C.
Cold storage helps stabilize market prices and evenly distribute goods both on demand basis and time basis. The farmers get the opportunity of producing cash crops to get remunerative prices. The consumers get the supply of perishable commodities with lower fluctuation of prices.
Ammonia and Freon compressors are commonly used in cold storage warehouses to maintain the temperature. Ammonia refrigerant is cheaper, easily available and has a high latent heat of evaporation but it is also highly toxic and can form an explosive mixture when mixed with oil containing high percentage of carbon. Insulation is also important, to reduce loss of cold and to keep different sections of the warehouse at different temperatures.
There are two main types of refrigeration system used in cold storage warehouses, a Vapour absorption system (VAS) and Vapour compression system (VCS). VAS, although comparatively costlier, is quite economical in operation and adequately compensates the higher initial investment.
The temperature necessary for preservation depends on the storage time required and the type of product. In general, there are three groups of products, foods that are alive (e.g. fruits and vegetables), foods that are no longer alive and have been processed in some form (e.g. meat and fish products), and commodities that benefit from storage at controlled temperature (e.g. beer, tobacco).
Location is a very critical aspect for the success of cold storage. It should be in close proximity of a growing area as well as a market, be easily accessible for heavy vehicles, and have uninterrupted power supply.
[edit] Cold storage and the law
There are state and local laws which regulate the cold store industry, requiring safe working conditions for employees, and operational procedures must be in accordance with these laws. Those companies which do their homework and prepare in advance for inspections and other routine enforcement protocols will be able to continue operating at full capacity, ensuring greater customer service and more product flow seven days a week.
[edit] Refrigerated warehouse industry
Refrigerated warehousing industries make up approximately one fifth of the market size of general warehousing.[9] Most of the market is concentrated in the Midwest, but California has the largest market share of the states. In 2006, the average market size of the industry was slightly over $3 billion, and the market continued growing in the following half decade.
[edit] Internet impact
19th century warehouse in Frankfort, Kentucky, United States used to age bourbon whiskey casks, seen closely through the warehouse windows
Internet-based stores do not require physical retail space, but still require warehouses to store goods. This kind of warehouse fills many small orders directly from end customers rather than fewer orders of many items from stores.
Having a large and complex supply chain containing many warehouse can be costly. It may be beneficial for a company to have one large warehouse per continent, typically located centrally to transportation. At these continental hubs, goods may be customized for different countries. For example, goods get a price ticket in the language of the destination country. Small, in-warehouse adjustments to goods are called value added services.
Material handling equipmentFrom Wikipedia, the free encyclopedia
Jump to: navigation, search
Industrial mezzanine.
Selective pallet rack is an example of storage and handling equipment.
Forklifts are the most common type of industrial truck.
A Miniload AS/RS - an example of an engineered system
Industrial KUKA Robots for palletizing - an example of an engineered system
Material handling equipment are equipment that relate to the movement, storage, control and protection of materials, goods and products throughout the process of manufacturing, distribution, consumption and disposal. Material handling equipment is the mechanical equipment involved in the complete system.[1] Material handling equipment is generally separated into four main categories: storage and handling equipment, engineered systems, industrial trucks, and bulk material handling.
[edit] Ways in Which Material Handling Equipment Can Improve Efficiency
Material handling equipment is used to increase output, control costs, and maximize productivity. There are several ways to determine if the material handling equipment is achieving peak efficiency. These include capturing all relevant data related to the warehouse’s operation (such as SKUs), measuring how many times an item is “touched” from the time it is ordered until it leaves the building, making sure you are using the proper picking technology, and keeping system downtime to a minimum.
[edit] Types of Material Handling Equipment
[edit] Storage and handling equipment
Storage and handling equipment is a category within the material handling industry. The equipment that falls under this description is usually non-automated storage equipment. Products such as pallet racking, shelving and carts, among others, belong to storage and handling. Many of these products are often referred to as "catalog" items because they generally have globally accepted standards and are often sold as stock materials out of Material handling catalogs.
[edit] Engineered systems
Engineered systems are typically custom engineered material handling systems. Conveyors, Handling Robots, AS/RS, AGV and most other automated material handling systems fall into this category. Engineered systems are often a combination of products integrated to one system. Many distribution centers will optimize storage and picking by utilizing engineered systems such as pick modules and sortation systems.
Equipment and utensils used for processing or otherwise handling edible product or ingredients must be of such material and construction to facilitate thorough cleaning and to ensure that their use will not cause the adulteration of product during processing, handling, or storage. Equipment and utensils must be maintained in sanitary condition so as not to adulterate product.
[edit] Industrial trucks
Industrial trucks usually refer to operator driven motorized warehouse vehicles, powered manually, by gasoline, propane or electrically.[2] Industrial trucks assist the material handling system with versatility; they can go where engineered systems cannot. Forklift trucks are the most common example of industrial trucks but certainly aren't the extent of the category. Tow tractors and stock chasers are additional examples of industrial trucks. Their greatest advantage lies in the wide range of attachments available; these increase the truck ability to handle various types and shapes of material.
[edit] Bulk material handlingMain article: Bulk material handling
Bulk material handling equipment is used to move and store bulk materials such as ore, liquids, and cereals. This equipment is often seen on farms, mines, shipyards and refineries. This category is also explained in Bulk material handling.
[edit] On-Rails Transfer Cart
On-rails transfer cart is a kind of material handling equipment. It moves on the rails and can transfer heavy cargoes or equipment with the weight 1-300t between the workshops or warehouses in the factory. It is widely used in the line of metallurgy, coal, heavy manufacturing, automotive assembly, etc. Its power can be AC or DC. DC Power has rail transmit power and battery power, while AC power includes cable power and slippery touch line power. In addition, there is the manual rail transfer cart or towed rail transfer cart, also called motorized transfer trolley.
[edit] Conveyors
Conveyors are another form of material handling. Conveyors can be used in a multitude of ways from warehouses to airport baggage handling systems. Some types of conveyors are unibilt, power and free, chain, towline and roller conveyors.
