5: Process Design

5: Process Design

1. What is process design?

   • Design happens before creation
   • Process design should reflect process (performance) objectives: Quality, Speed, Dependability, Flexibility, Cost
     • Throughput rate Throughput time Work in process Utilization
   • Environmentally sensative
     • Sources of Inputs, Quantities + sources of energy, Waste material, End-of-life of product

2. Process types - Volume-variety effect

   • Volume-variety positions
   • Low-volume -> High variety High-volume -> low variety
   • Project processes
     • Jobbing processes
       • Batch processes
         • Mass processes
           • Continuous processes
   • Professional services
     • Service shops
       • Mass service
   • Product-process Matrix -> How cost and flexibility vary with process choice
     • "natural" diagonal -> fit of process to volume/variety

3. Detailed process design

   • Process mapping = Process blueprinting = Process analysis
     • How activities within the process relate to each other
     • High-Level process mapping
       • Draw process as an input-transformation-output process
         • Outline process map
   • Process maps to improve processes
     • Work content
     • Throughput time = Work-in-process x Cycle time 10 min. wait = 10 People wait x 1 min. per person
       • = Little's law
       • Throughput Efficiency = Work Content / Throughput time x 100
         • Value-added throughput efficiency -> only work content that adds value
   • Balancing -> Work Content equally to each stage in process
     • Balancing loss -> time wasted trough unequal allocation of work
       • Bottleneck -> longest stage in process
   • Long thin
     • Short fat
       • Higher mix flexibility, higher volume flexibility, higher robustness, less monotonous work
     • controlled flow, simple material handling, lower capital requirements, more efficient
   • Process variability
     • in demand
     • in time to perform activity
     • relationship btw. average waiting time and process utilization is important

4. Human implications for process design

   • Division of labour
     • Scientific Management --> Taylorism
       • Work study=
         • Method study -> methods/activities to be included in jobs
         • Work measurement -> measuring time for job
   • Ergonomics
     • Human factors engineering
   • Behavioural approach
     • Job rotation
       • Job enlargement
         • Job enrichment
           • Empowerment
             • Team-working