Tuesday, January 8, 2008
Mechanised Systems
Forklift truck 
Forklift truck can move loads of master cartons both horizontally and vertically. A forklift truck, a lift truck, a High/Low or a forklift and sideloader is a powered industrial truck used to lift and transport materials, normally by means of steel forks inserted under the load. Forklifts are most commonly used to move loads stored on pallets.It has since become an indispensable piece of equipment in manufacturing and warehousing operations.
Design types
There are many national and/or continental associations related to the industrial trucks. The three major ones are the Industrial Truck Association (North America), the Fédération Européenne de la Manutention (Europe), and the Japan Industrial Vehicles Association (Japan). There are many significant contacts among them and they have established joint statistical and engineering programs. One program is the WITS (World Industrial Trucks Statistics) published every month to the association memberships.
List of the more common truck types, from the smallest to the biggest:Hand Pallet Truck
Walkie low lift truck (powered pallet truck, usually electrically powered)
Rider low lift truck
Towing tractor
Walkie stacker
Rider stacker
Reach truck (small forklift, designed for small aisles, usually electrically powered)
Electric counterbalanced truck
IC counterbalanced truck
Sideloader
Telescopic handler
Slip Sheet machine
Walkie Order Picking truck
Rider Order Picking truck (commonly called an "Order Picker"; like a small forklift, except the operator rides up to the load and transfers it article by article)
Characteristics
A typical 'Counterbalance' forklift may be generally described as follows:
- The truck proper, which is a motive machine with wheels or tracks powered through a drive train.
- A liquefied petroleum gas–, petrol- or diesel fueled internal combustion engine, or an electric motor(s) either direct current or alternating current powered by either a battery or fuel cells.
- The mast, which is the vertical assembly that does the work of raising, lowering, and tilting the load; the mast is either hydraulically operated consisting of one or more cylinder(s) and interlocking rails for lifting and lowering operations and for lateral stability, or it may be chain operated with a hydraulic motor providing motive power.
- The carriage, which comprises flat metal plate(s) and is moved along the mast either by means of chains, or by being directly attached to the hydraulic cylinder.
- Counterbalance machines have a counterweight, which is a heavy iron mass attached to the rear of the machine, necessary to compensate for the load. In an electric forklift, the large lead-acid battery itself may serve as part of the counterweight.
Guided Very Narrow Aisle trucks
These are rail or wide guided and available with lift heights up to 12 metres (40') non top-tied and 30 metres (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.
Control and capability
Forklift trucks are available in many variations and load capacities. In a typical warehouse setting most forklifts used have load capacities of around one to five tons, though machines of over 50 tonnes capacity have been built and operated.
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. Some machines also allow the operator to move the tines and backrest laterally (side-shift), allowing easier placement of a load. To aid the handling of skids that may have become excessively tilted and other specialty material handling needs, some forklifts are fitted with a mechanism that allows the tines to be rotated. In addition, a few machines offer a hydraulic control to move the tines together or apart, removing the need for the operator to get out of the cab to manually adjust for a differently sized load.
Forklift Safety
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.
Other standards have been promulgatd by the U.S Occupational Safety and Health Administration and the United Kingdom's Health and Safety Executive. Lift truck operators must be trained and certified.
Four companies dominating the market
-Toyota IndustriesCorporation (3.47 M€ in '03/04)
-KION Group(2.94 M€ in '03)
-Jungheinrich (1.35 M€ in '03)
-NACCO Industries, Inc.(NMHG) (1.27 M€ in '03) with Yale and Hyster Brands
The following is a hyperlink to the history of forklift
http://www.datakey.org/mhedajournal/3q04/lifttrucks_a.php3\References:http://en.wikipedia.org/wiki/Forklift
Conveyor
A belt conveyor consists of two or more pulleys, with a continuous loop of material - the conveyor belt - that rotates about them. One or both of the pulleys are powered, moving the belt and the material on the belt forward. The powered pulley is called the drive pulley while the unpowered pulley is called the idler. There are two main industrial classes of belt conveyors; Those in general material handling such as those moving boxes along inside a factory and bulk material handling such as those used to transport industrial and agricultural materials, such as grain, coal, ores, etc. generally in outdoor locations.
The belt consists of one or more layers of material. Many belts in general material handling have two layers. An under layer of material to provide linear strength and shape called a carcass and an over layer called the cover. The carcass is often a cotton or plastic web or mesh. The cover is often various rubber or plastic compounds specified by use of the belt. Covers can be made from more exotic materials for unusual applications such as silicone for heat or gum rubber when traction is essential.
Wide variety of related conveying machines are available, different as regards principle of operation, means and direction of conveyance, including screw conveyors, vibrating conveyors, pneumatic conveyors, the moving floor system, which uses reciprocating slats to move cargo, and roller conveyor system, which uses a series of powered rollers to convey boxes or pallets.
Conveyors are used as components in automated distribution and warehousing. In combination with computer controlled pallet handling equipment this allows for more efficient retail, wholesale, and manufacturing distribution. It is considered a labor saving system that allows large volumes to move rapidly through a process, allowing companies to ship or receive higher volumes with smaller storage space and with less labor expense.
Typical Construction of a Conveyor systems Belt Bend
Belt Conveyor systems at a Packing Depot
Baggage Handling Belt Conveyor systems
Few types of Conveyors
Snake Sandwich Belt Conveyor
A sandwich belt conveyor uses two conveyor belts, face-to-face, to gently but firmly contain the product being carried, hence making steep incline and even vertical-lift runs easily achievable. The Snake Sandwich Belt Conveyor was created in 1979. The study was conceived by Joseph A. Dos Santos, P.E., President of Dos Santos International, with the help of a grant from the U.S. Bureau of Mines. The study was to develop a means of moving and elevating large quantities of bulk materials, including coarse products such as rocks, aggregate, coal, etc. at the steepest possible inclines. The intent was to use only existing and generally available hardware in order to achieve the most economically feasible and easily maintained steep-angle conveyor design. Snake Conveyors are available in widely ranging profiles of C and S Shape. In any case, a long bottom belt approach is possible to the sandwich entrance, and discharge may be on the high incline or may be after the extension of the carrying belt beyond the mouth of the sandwich. Snake Sandwich conveyors offer several advantages. First unlimited conveying capacity, a system suitable for the most rugged mine applications and gentle on sensitive and friable materials, high availability and low operating and maintenance costs, smooth surfaced belts allowing continuous belt cleaning by scrapers and plows. This also facilitates intermediate material discharge by belt plows, as appropriate, before and/or beyond the sandwiched part of the Snake profile. All conventional conveyor hardware insures economy and fast delivery of replacement parts.
Vibrating Conveyor Systems
A Vibrating Conveyor is a machine with a solid conveying surface which is turned up on the side to form a trough. They are used extensively in food grade applications where sanitation, washdown, and low maintenance are essential. Vibrating conveyors are also suitable for harsh, very hot, dirty, or corrosive environments. They can be used to convey newly cast metal parts which may reach upwards of 1500°F. Due to the fixed nature of the conveying pans vibrating conveyors can also perform tasks such as sorting, screening, classifying and orienting parts. Vibrating conveyors have been built to convey material at angles exceeding 45° from horizontal using special pan shapes. Flat pans will convey most materials at a 5° Incline from horizontal line.
Flexible Conveyor Systems
The flexible conveyor is based on a conveyor beam in aluminium or stainless steel, with low friction slide rails guiding a plastic multi-flexing chain. Products to be conveyed travel directly on the conveyor, or on pallets/carriers.
Pneumatic Conveyor Systems
Products are moved through various tubes via air pressure, allowing for extra vertical versatility. Pneumatic conveyors are either carrier systems or dillute-phase systems; carrier systems simply push items from one entry point to one exit point, such as the money exchanging tubes used at a bank drive-thru window. Dillute-phase systems use push/pull pressure to guide materials through various entry and/or exit points.
Lets see a video on conveyor.
References
http://www.youtube.com/
http://en.wikipedia.org/wiki/Conveyor
Carousels
Horiziontal Carousel
-Horizontal carousels consist of an oval track with rotating bins containing shelves that deliver items to the operator. Often used in integrated workstations of carousels called a “pod.”
-It allows an operator to pick from one active carousel while the others are pre-positioning to be picked the moment the operator is ready.
-Vertical carousels consist of shelves that rotate up or down via the shortest path, delivering items to an ergonomically positioned pick window. The vertical design maximizes the use of overhead space and can recover up to 75% of the floor space required for traditional shelving systems.
-Vertical carousels are available in a wide range of heights, depths and widths to meet virtually any storage and retrieval requirement. They are compatible with an entire suite of software and controls to meet standard and unique applications.
Advantages
- Helps organizations meet Lean Manufacturing
- Brings inventory to point of use
- Shelves can be easily adjusted to meet future needs
- Improves operators productivity and ergonomics
- Higher MTBF (Mean Time Between Failure) rates than most household appliances
- Link multiple floors and/or areas with customizable pick windows
- Easy to use controls and/or multiple levels of software available
- Protect and/or secure single or multiple items
- More than 7,000 standard configurations
- Easily integrates bar code scanning and pick-to-light technology for increased throughput, productivity and accuracy levels
Carousels being an automated storage and retrieval system often provides advantages such as
- Increased throughput up to 600%
- Reduced floor space requirements up to 60%
- Flexible design provides instantly adjustable shelf levels
- Reduced labor up to 2/3
- Move and change workstation designs easily
- Workstation design that is easily modified Increased level of accuracy up to 99.9% levels
- The ability to increase or decrease a carousel's length easily
- Extended order cut-off times
- Fast ROI (Return On Investment)
References: http://www.remstar.com/ link | posted by <$T03$> at 9:37 PM
