What are the deciding factors for company to adopt carousel systems instead of other storage systems?
There are several factors for company to adopt carousel systems. The deciding factors include:
High labour cost
Excellent item protection and security
High accuracy in order picking
Excellent Supervision
Fully automation
Reduce picking time
Reduce picker idle time
-High labour cost: If the company is facing high labour cost, using carousel systems can help to solve the problem, where less manpower is needed to perform order-picking work.
-Excellent item protection and security: In the vertical carousel, only one shelf items is exposed at one time, and the entire contents of the carousel can be secured. Thus if the company is storing high valued products or fragile items, carousel can be the right storage system to them. In addition, carousel system can be used for handling hazard goods which may be too dangerous for humans to handle.
-High accuracy in order picking: The chances of picking wrong part is very slim, thus company which demand high accuracy in order picking should adopt this storage system.
-Excellent supervision: In stock to picker systems, the picking takes place at the end of an ailse. Thus any operators should be visible to a supervisor in one quick glance at a picking line, this helps to prevent anyone having the idea of stealing the items. For company that is dealing with high valued items, carousel can be the ideal storage system.
-Fully automation: If the company is intending to go from a manual handling system to a fully automated handling system, carousel, a form of AS/RS can be a good choice to adopt (see its advantages at the post Carousel).
-Reduce picking time: Order picker does not need to search for the items or to travel a distance to get the items, as the orders are entered into the system and the items is auto picked and retrieved by the machinery to the picker. Therefore, it is suitable for companies who wish to have a faster order picking rate.
-Reduce picker idle time: The objective of stock to order picker systems is to keep the picker picking. By assigning the order picker to two or more carousels, he or she may pick from one carousel while the other is rotating to the next pick station. This can help to improve the operation efficiency.
-Faster return of investment: Carousel system will be suitable for companies who wish to obtain the return of investment as soon as possible. Thus, they could use this for other purposes such as purchase of new assest or expansion.
Companies should not consider only on one deciding factor when adopting carousel system. In addition, they should consider the impact on the profit, the requirement met, the benefits gains, and other factors.
This design of racking system allows the pallet load to be fed into higher end, and to be retrieved from the lower end (so called as pallets move in the racking). After pallets are positioned at the end of the racking by, for example, a fork-lift truck, the movement in the racking is facilitated by having a structure that permits movement horizontally down the racking by incorporating rollers on which the pallets slides. The movement can be with gravity with, say, a 4% slope, or the pallets can be moved by powered rollers. The choice depends on individual company requirements and on safety requirements at a maximum speed of 0.3 metre per second. Live racking can be used to 'automatically' position pallets on a First-In-First-Out basis and also positon pallets in another part of the warehouse.
Advantages
-Floor storage space utilisation of up to 70% -Saves cost (e.g. manpower) -Increase picking productivity -High density storage
-No power source needed
Disadvantages
-Products cannot be kept long -High expensive set-up
Applications
Suitable for high throughput per line item and products that are of uniform size and shape.
The video below shows how the live storage operates:
The following case study illustrates usage of live racking:
CASE STUDY: LIVE RACKING AT BMW
Pallet live, carton live and mobile line side live-storage are all features of the investment that will help the plant to achieve a 39 second cycle time for engines to support the BMW group’s production network. The production of the engine requires a supply of 400000 varied components to assembly lines everyday.
Hams Halls is a pristine, state-of-the-art manufacturing and assembly facility for BMW’s 1.61.8 and 2 litre, four-cylinder ‘Valuetronic’ petrol engines, with highly automated operations that adhere to the principles of lean, JIT production.
‘Our storage and component delivery systems have to support a truly 21st- century enterprise,’ say Hughes of BMW, ‘a floor plan was devised for our “small container supermarket” comprising nine aisles of pallet live storage, providing 110 pallet pick locations, each with a reserve pallet location and a single tier carton live storage, above the empty pallet return system services each bay for efficient pallet return, safety and minimal congestion at the pick face.’
The feed sides face on to wide aisles, replenished by electric forklift trucks operating from a conveyor feed from an auto store, while special commissioning vehicles operate in narrow aisles fronting the pick face.
‘The components within the bays are positioned in such a way as to allow the components to be picked sequentially, exactly in the order that they will be required at the production line. There is no need for pick vehicles to back up or travel along the feed aisles.’ says Hughes.
Inside the main assembly hall, engine sub-assemblies are delivered to work stations by AGV’s (automated guided vehicles). At these stations, line side live units are an integral part of a pick-to-light system. Ergonomics are a key consideration and the minimal motion required of operators at each station is immediately noticeable.
‘The main live storage installation services our slow moving components which on average draws between one and two boxes of a particular part number, per hour’ explains Hughes. ‘Fast moving components are delivered to the line by pallet-load.’
A consideration when specifying the project was that the storage system could keep pace with increasing complexity as various engine derivatives are introduced into the build schedule. The static carton live bays will eventually take many channels each and there is capacity to put at least 300 part numbers through the system, which should satisfy long-term projections for the plant.
Source: Industrial Handling and Storage, October/November 2001.
These are available for handling and storage and result in tall warehouse buildings, over 15 mtres high. These systems will definitely favour those warehouse operations that have a low product range with high throughput levels (minimum two shifts and over 60 pallets per hour), and operations where the following advantages can be exploited:
has a 24/7 operational capability
high labour cost reduction
ability to increase output rate
improvement in consistency of service
reduction in materail handling
increased accuracy level
service availability
improvement in speed of service
improves security and reduces pilferage as people access is limited
is useful for dangerous operating environments like chemicals (as they are practically operator free)
products have standardised dimensions and weights and products identification
The disadvantages of automated warehouses can be summarised as:
high initial capital costs and payback periods of 3-4 years minimum
slow return on investment, which can be up to 7-10 years
Small Item Storage System - Bin Shelving - Modular Storage Drawers - Louvre Panel System
Small item storage systems include a range of highly adaptable storage means that are specially designed to bring order to the storage of small items. These items could come in different size and shape.
A Well-Designed small item storage
Minimize the manual effort in lifting and handling
Store and retrieve thousands of small items in a single bay of shelving
Quick and easily pick small items
Utilize the maximum amount of cubic space
Store small parts & packages in the same racks
Subdivide bins for extra efficiency
Ease of location identification
Bin Shelving System
Bin (or metal) shelving systems are the oldest and still the most popular (in terms of sales volume dollars and the number of systems in use) equipment alternative for small parts order picking. Bin shelving systems are inexpensive, easily reconfigured, and require very little if any maintenance.
Unfortnately, the lowest initial cost alternative may not be the most cost-effective alternative, or the alternative that meets th prioritized needs of a warehouse. With bin shelving systems, savings in initial cost and maintenance may be offset by inflated space and labour requirements.
Modular Storage Drawers/Cabinets
Modular storage drawers/cabinets are called modular because each storage cabinet house modular storage drawers that are subdivided into modular storage compartments. Drawer heights range from 3 inches to 24 inches, and each drawers may hold up to 400 pounds worth of materia. Storage cabinets can thought of as shelving units that house storage drawers. The primary advantage of storage drawers/cabinets over bin shelving is the large number of items that can be stored and presented to the order picker in a small area.
Louvre Panel System
Louvre panels provide flexibility which allows for a huge range of storage solutions for workshop, stores and commercial environments. They can also be mounted on to trolleys for movement, on the wall or rack format. For example, it is applied between storage and assembly operations. They can be used to hold tote pans, plastic bins and other attachments for more awkwardly shaped items such as tool holders.
Carousels, as the name implies, are mechanical devices that house and rotate items for order picking. The most frequently utilised carousel configurations are the horizontal and vertical systems.
Vertical Carousel
The vertical carousel consists of a number of shelves connected at the ends to powered chains that can rotate vertically. Each shelf carries multiple bins. Most of the vertical carousels are contained in a closed chamber with only an opening at the position of the operator. This allows for good protection of the stored items. The compact construction allows vast storage capacity to be accommodated on minimal floor space by making use of the available room height thus saving costs. Some advantages of this system are easy rapid retrieval, short access times, ease of operation and protection from dirt and damage.
Horizontal Carousel The horizontal carousel consists of a large number of carriers driven by a powered chain that can rotate horizontally around a narrow closed loop. Each carrier consists of multiple bin positions. It can be driven forwards, or backwards to bring the required stock to the operator. Horizontal carousel systems save up to 60% of otherwise wasted floor space. In addition, the carousels provide dramatic productivity enhancing features. The newly freed-up floor space can be converted for value-added purposes. There are also other advantages such as, accommodate more parts in less floor space, items are conveniently brought to the operator and inventory are 100% accessible at all times.
For example, the Park Seed Company in South Carolina, the largest family-owned mail order seed company in the world, must be able to fill customers' orders within 24 to 36 hours during the peak season of December to April. Because of increasing business, the firm replaced its 125-year-old wooden bin system with automated horizontal carousels. As a result, the lines picked per hur per operator increased five times while labour was reduced by one-third. Compared to the old system, picking speed increased from 180 to 950-1,000 lines picked per hour.
There are many different types of racking available, and our group has chosen the key features for 4 of the racking, shown in table 1.
Mezzanine
Bin shelving, modular storage cabinets, flow rack, carousels and pigeonhole racking can be placed on a mezzanine (refer to the picture below). The advantage of using a mezzanine is that nearly twice as much material can be stored in the original square footage. The major design issues for a mezzanine are the selection of the proper grade of mezzanine for the loading that will be experienced, the design of the material handling equipment system to service the upper levels of the mezzanine, and the utilisation of the available clear height. At least 14 feet clear height should be available for a mezzanine to be considered. The cost of a typical mezzanine system is $10 to $20 per square foot.
