27-05-2014, 10:51 AM
ANALYSIS OF SINGLE MODEL ASSEMBLY LINES
ANALYSIS OF SINGLE MODEL .pdf (Size: 394.71 KB / Downloads: 12)
Production Rate
The assembly line must be designed to
achieve a production rate sufficient to satisfy the demand.
Demand rate → production rate→ cycle time
Annual demand Da must be reduced to an
hourly production rate Rp
Cycle Time
Line efficiency: Uptime proportion. Accounts for lost
production time due to equipment failures, power outages,
material unavailability, quality problems, labor problems.
Production rate Rp is converted to a cycle time Tc,
accounting for line efficiency E
Losses in Line
Repositioning losses:
Some time will be lost at each
station every cycle for repositioning the worker or the
work unit; thus, the workers will not have the entire Tc
in each cycle
Line balancing problem:
It is not possible to divide the
work content time evenly among workers, and some
workers will have an amount of work that is less than Tc
Repositioning Losses
Repositioning losses occur on a production line
because some time is required each cycle to reposition
the worker, the work unit, or both
On a continuous transport line, time is required for
the worker to walk from the unit just completed to the
upstream unit entering the station
In conveyor systems, time is required to remove work
units from the conveyor and position it at the station
for worker to perform his task.