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My point of view a modern warehouse need to following equipment
Powered equipment include trucks, cranes, conveyors, etc. Non -powered equipment include hand-pallet trucks, order picking trolleys, stair climbing trolleys, shelf and cage trolleys.
Industrial lift trucks are used in warehousing for moving material over relatively short distances, for lifting into and out of storage, and for vehicle loading and unloading. Trucks facilitate load utilization and speed up movement. They can handle large loads and consequently reduce the frequency of movements. Their lift ability enables building height thus reducing the cost of building volume by increasing building height.
The main types of powered trucks used in warehousing and stock yard operations are:
Conveyors for Unit Load Handling
Conveyor systems are used for moving material between fixed points, for holding material as short-term buffer, for sortation and for process industry applications such as separation, grading and cooling.
The advantages of using conveyor systems include:
Conveyor systems have wide applications in both conventional and automated warehousing.
Some of the drawbacks of conveyor systems include:
Automated Storage and Retrieval Systems (AS/RS)
This section contains an overview of some of the more sophisticated handling and storage systems to be found in warehousing applications. They include highly mechanized systems, automated systems with computers controlling the physical movement and storage of materials, and robotic applications. Such applications may be said to be at the technologically advanced end of the equipment and system spectrum in the context of warehousing, although some of the technology is well established and has been with us for many years.
‘High-tech’ installations are costly, involve 24-hour working, are somewhat inflexible and tend to require long payback periods. Installation should be based on some assurance of long-term demand for the products handled. An example is the use of automated storage and retrieval systems (AS/RS) using computer-controlled driverless high lift stacker cranes in high bay warehouses, a concept that has been with us since the early 1960s. In this sort of application the computer is used to manage and control the physical movement of equipment, and hence of the materials being handled and stored. Many of the earlier stacker cranes were operator-controlled, but the facility for on-board operation is now more usually for maintenance purposes only.
During the last 10 to 15 years the pace of technological development and application has increased considerably. This has gone hand in hand with, and been encouraged by, the growth in information technology, and has been motivated by the increasingly tight requirements for accurate and timely customer service, and for inventory and cost reduction.
AS/RS Systems for Unit Loads
The basic components of an AS/RS system are:
The controlling computer monitors the status of all the components of the system and, based on the warehouse stock and movement requirements, plans the work to be carried out within the system and instructs the equipment accordingly.
A typical installation could consist of high bay pallet racking, with stacker cranes operating in the racking aisles to put pallets away to stock and to retrieve them as required. Note that there are single deep and double deep stacker cranes, enabling the use of single or deep pallet racking on each side of each aisle. Installation heights of 45 meters or more can be achieved, and typical operating aisles for standard pallets can be about 1.5 meters.
The computer would control the incoming and outgoing material flows, monitor the status of the pallet racking (what stock is located in each location and which locations are empty), and control the crane movements. Because of the generally tight clearances in such installations and to prevent possible jams in the racking, a strict profile check for incoming pallets is adopted to ensure that loads have not slipped on the pallets during transit, and that packaging material has not come loose. Pallets outside the dimensional specification are rejected, and have to be rectified before being accepted into the system.
Benefits of AS/RS Systems:
