Figure 5.6 shows a schematic of a manufacturing system. There are four categories of manufacturing processes. They are:
Fabrication process ” which can be further categorized as basic process, secondary process, or finishing process. Typical types are:
Single station
Continuous production flow
Pace production line
Manufacturing cell approach
Assembly process ” which can be further categorized as manual assembly, mechanical assembly, automatic assembly, or computer-aided assembly. Typical types are:
Continuous transfer
Intermittent transfer
Indexing mechanisms
Operator-paced free-transfer machine
Inspection or quality control process
Inspection check point(s)
Material handling process
Conveyors
Tractors
Fork lifts
Parts/component feeding system:
Vibratory bowl feeder
Reciprocating tube hopper feeder
Centerboard hopper feeder
Reciprocating fork hopper feeder
External gate hopper feeder
Rotary disk feeder
Centrifugal hopper feeder
Revolving hook hopper feeder
Stationary hook hopper feeder
Bladed wheel hopper feeder
Tumbling barrel hopper feeder
Rotary centerboard hopper feeder
Magnetic disk feeder
Elevating hopper feeder
Magnetic elevating hopper feeder
Approaches to manufacturing processes include the job shop approach, the assembly line approach, and the one in, one out approach. Details of these processes are as follows :
Singled station manufacturing process ” job shop approach
Definition: Single fixture with one or more operations performed
Advantages:
Capital investment ” low
Line balance ” not needed
Interference with other operations (downtime) ” minimum, if any
Flexibility ” easy to expand or rearrange
Employment fulfillment ” high
Disadvantages:
Multiple tooling/fixture investment ” high
Material handling ” high
Material flow ” easy to congest at in/out
Operation cycle time ” long
Operator skills ” moderate
Continuous production flow manufacturing process ” assembly line approach
Definition: Continuous, sequential motion assembly/manufacturing approach
Advantages:
Work-in-process ” low
Manufacturing/assembly cycle time ” low
Material handling ” very low, if not eliminated
Material flow ” good
Operator skill/training ” only in specialized areas
Disadvantages:
Capital investment ” high
Preventative maintenance and corrective maintenance ” absolute necessity (If one part breaks down, the entire line is down.)
Engineering, technician, and flow disciplines ” absolute necessity
Flexibility ” low
Production changeover ” complicated
Pace production line ” one in, one out
Definition: Same cycle time at all work stations , and likely all work pieces transfer at the same time
Advantages:
Work-in-process ” very low and can be calculated
Material handling ” automatic
Material flow ” good
Productivity ” best
Disadvantages:
Capital investment ” high
Preventative maintenance and corrective maintenance ” absolute necessity (If one part breaks down, the entire line is down.)
Engineering, technician, and flow disciplines ” absolute necessity
Flexibility ” very low
Production changeover ” difficult