Page 280 - DMGT501_OPERATIONS_MANAGEMENT

Operations Management

Notes 7. Automated Storage and Retrieval System (AS/RS) are storage rack systems in which each
location and its inventory status is maintained by a computer-controlled central unit.
When a certain item is needed, a computer, using its status file, locates the item on the
shelf. To retrieve the part, a driverless device, such as an AGV, automatically picks up the
item. In case of new items, the location of the rack where it is to be stored is communicated
by the computer to the lifting device. Subsequently, the inventory status is updated.

Material Handling Equipment

Material handling is an important part of managing materials. How will the material be moved?
Physically moving material requires equipment of various kinds, depending on the type and
amount of material to be moved.
Cost-efficient material handling is an important issue.

Did u know? Material movement usually accounts for about 25% of total factory cost,
therefore, a careful study of alternative modes of material transportation are very
important.
There are some guiding principles of material handling. These are:
1. Reduce unnecessary movement by selecting the shortest path to reach the destination.
2. Reduce congestion and bottlenecks by eliminating obstruction and congestions in the
material handling.
3. Use scientific factory layout to minimize the overall material movement and reduce the
number of trips. This will result in reduced transportation costs.
4. Use of standard material handling equipments to facilitate easy maintenance and
availability of spares.
5. Minimize handling as it reduces the chances of breakage. It also reduces loading/unloading
time and cost.
6. Use gravity to transport material, wherever possible.
7. Use mechanized material handling equipment to reduce dependence on human labour.
The attempt in material handling is to use flexible equipments wherever possible and specialized
equipment, only if necessary. The equipment should be simple and safe with operator safety as
the prime objective. Listed below are a few material-handling devices and when they might be
used.
1. Overhead Cranes and Hoists: Overhead cranes and hoists are used to move heavy objects
through a plant. They are used for the movement of material in a fixed route and fixed area
of operation. They come in a variety of sizes, and many are able to lift twenty-five tons or
more. Moving steel slabs is an example of an overhead crane application. Overhead cranes
are efficient at moving small parts only if the parts can be put together in a large batch and
moved in one trip.
2. Conveyors: Conveyors are used to transport material from one fixed point to another
fixed point. Some conveyors have belts that can move parts or granular material; others
have a series of hooks that can move parts through a paint system. Some use gravity or a
powered device to carry material. Some of the conveyor systems are portable which may
be moved from time to time, but generally these are fixed. These are used for the following
applications:
(a) Moving homogeneous material

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