Operations Management Chapter 6: Process Design and Facility Layout

Process Design
Determining the form and function of how goods and services are produced.
Variety
Refers to how much.
Flexibility
Refers to what degree.
Volume
Refers to the expected output.
What are the 4 different Process Types
1. Job Shop
2. Batch.
3. Repetitive.
4. Continuous.
Job Shop (Process Type)
A process type that is low volume, high variety, small runs, intermittent processing, high flexibility of equipment, skilled workers, low fixed costs, complex scheduling, and high WIP inventory.
Batch (Process Type)
A process type that is moderate volume, moderate variety, less flexible equipment and less skillful workers than in a job shop environment.
Repetitive (Process Type)
A process type that is semi-continuous, has slight flexibility of the equipment, skill of workers is low, routine scheduling, and low WIP inventory. (Ex. Assembly line)
Continuous (Process Type)
A process type that is high volume, highly standardized equipment, high fixed costs, low variable costs, and low WIP inventory.
Hybrid Processes
When a process has elements of another process type.
Ex. Focused Factory or Mass Customization
Focused Fatory
Specialized in a high quantity, standardized product.
Mass Customization
Producing high quantity and high variety efficiently
Technology
Applications of scientific discoveries to the development and improvement of goods and services and/or the processes that produce or provide them.
Process Technology
Methods, procedures, and equipment used to produce goods and provide services.
2 Examples of Process Technology
Robotics and Automation on the factory floor.
4 Examples of Technology
Knowledge, materials, methods, and equipment.
Information Technology
The science and use of computers and other electronic equipment to store process and send information.
What are the 3 Types of Automation?
1. Fixed Automation.
2. Programmable Automation.
3. Flexible Automation.
Fixed Automation
1. Very rigid.
2. High cost, specialized equipment for a fixed sequence of operations.
Programmable Automation
1. High cost, general purpose equipment controlled by a computer program.
2. Numerically Controlled Machines (CNC, DNC, robots)
Flexible Automation
1. Customized Equipment.
2. Computer-aided design (CAD/CAM), flexible manufacturing systems (FMS), and computer-integrated manufacturing (CIM)
Automation
Machinery with sensing and control devices that enable it to operate automatically.
Process Design
Identifying the activities, resources, and controls needed in the production process
3 Steps in Defining the Production Process (Operations Assessment in Stage 2 of the Stage-Gate model)
1. Make-or Buy Decisions.
2. Set objectives.
3. Determine nature of process in general.
3 steps in Production Process Development (Operations Assessment in Stage 3 of the Stage-Gate model)
1. Conceptualize the design.
2. Make an embodiment of the design.
3. Create a detailed design.
3 Steps in Implementation (Operations Assessment in Stage 4 of the Stage-Gate model)
1. Buy machines and equipment.
2. Recruit workers.
3. Start trial runs
Layout
The arrangement of departments, work centres, equipment, etc.
Product (Line) Layout
Arranges production resources linearly according to the progressive steps by which a product is made. (Used for Repetitive or Continuous Processing)
Process Layout
Arranges production resources together according to a similarity of function. (Used for intermittent processing such as Job Shop or Batch processes. Common in services)
5 Advantages of Product Layouts
1. Efficient and Easy to use.
2. High degree of labour & equipment utilization.
3. Minimal WIP inventories.
4. Simplified accounting, purchasing, and inventory control
5. Easier training and supervision.
5 Disadvantages of Product Layouts
1. Inflexible
2. Higher equipment cost
3. Dull, repetitive jobs = stress and low morale.
4. Lack of flexibility in product or production rates
5. Work stoppage at any point ties up the whole operation.
3 Advantages of Process (Functional) Layouts
1. Flexibility.
2. Less vulnerable to shutdown (from mechanical failure or absenteeism)
3. Lower maintenance costs (and reduced investment in spare parts)
4 Disadvantages of Process Layouts
1. Inefficiency
2. Scheduling can be difficult (= low equipment utilization rates)
3. Setup, material handling, and labour/costs can be high.
4. Increased WIP inventory.
Cellular Layout
Layout in which machines are grouped into a cell that can process items that have similar processing requirements.
Group Technology
The grouping into part families of items with similar design (size, shape, and function) or manufacturing (type and sequence of operations required) characteristics.
3 Benefits of Cellular Layouts
1. Faster processing time and reduced setup times.
2. Increased capacity
3. Less material handling and WIP inventory
Warehouse Layouts
Important consideration on the Frequency of Order.
Retail Layouts
Important consideration on Traffic Flow.
Office Layouts
The objective of this layout is to optimize the physical transfer of information on paperwork.
Restaurant Layout
Important consideration on Process Workflow
Hospital Layout
Important considerations on Patient Care & Safety, easy access to critical resources such as X-Ray, CAT scan, and MRI equipment.
Assembly Line Balancing
The process of assigning tasks to workstations so that workstations have approx. equal time requirements.
Cycle Time
The maximum time allowed at each workstation to complete its set of tasks on a unit.
Output Capacity Formula
Operating Time Per Day (OT) / Cycle Time (CT)
Cycle Time Formula
Operating Time (OT) / Desired Output Rate (D)
Nmin
Theoretical minimum number of workstations.
Et
Sum of the task times
Nmin (Theoretical minimum number of workstations.) Formula
Et / CT