Process Selection & Facility Layout: Types, Trade-offs & Design

Core Concepts

1. Process Selection: Matching Process to Product

Operations managers must align process type with product volume, customization, and cost goals. The four primary process types form a spectrum from high flexibility/low volume to low flexibility/high volume:

mindmap
  root((Process Selection Spectrum))
    Job Shop
      "Low volume, high customization (e.g., tailor-made furniture)"
      "General-purpose equipment"
      "High skilled labor"
      "Example: Nepali wedding dressmakers"
    Batch
      "Moderate volume, some customization (e.g., bakery orders)"
      "Flexible equipment, setup time"
      "Example: Daraz’s small-batch electronics assembly"
    Mass (Assembly Line)
      "High volume, standardized products (e.g., Ncell phones)"
      "Specialized equipment, low-skilled labor"
      "Example: Toyota’s car assembly lines"
    Continuous
      "Very high volume, no customization (e.g., NTC’s electricity grid)"
      "Highly automated, dedicated facilities"
      "Example: Himalayan Java’s coffee bean processing"

Key Trade-offs:

Worked Example: Daraz’s Order Fulfillment Daraz uses a hybrid batch/mass process for its e-commerce operations:

1. Batch: Small orders (e.g., books, electronics) are picked manually in batches from warehouses (flexible but slower).
2. Mass: High-demand items (e.g., mobile phones, groceries) use automated sorting and conveyor belts (faster, lower cost).
   • Trade-off: Daraz balances speed vs. customization by segmenting products.
   • Real Layout: Warehouses are designed with zone-based layouts (e.g., "fast-moving items" near shipping docks).

2. Facility Layout: Designing Workflow Efficiency

Layout design directly impacts cost, speed, and employee morale. The four main layouts address different process needs:

mindmap
  root((Facility Layout Types))
    Product Layout
      "Linear flow for high-volume products (e.g., assembly lines)"
      "Minimizes material handling"
      "Example: Ncell’s phone manufacturing"
    Process Layout
      "Group similar machines/tools (e.g., job shops)"
      "Flexible but inefficient for high volume"
      "Example: Kathmandu’s garment factories"
    Fixed-Position Layout
      "Product stays fixed (e.g., shipbuilding, construction)"
      "High coordination needed"
      "Example: Himalayan Java’s coffee plantation processing"
    Cellular Layout
      "Small teams with dedicated equipment (e.g., U-shaped cells)"
      "Balances flexibility and efficiency"
      "Example: Toyota’s *kaizen* cells for car parts"

Decision Framework for Layout Selection Use this flowchart to choose the right layout:

flowchart TD
  A["Start: What is the product volume?"] --> B{"High Volume?"}
  B -->|"Yes"| C["Use Product Layout"]
  B -->|"No"| D{"Is customization high?"}
  D -->|"Yes"| E["Use Process Layout or Cellular"]
  D -->|"No"| F["Use Mass Production Layout"]
  E --> G["Assess team size: Small teams?"]
  G -->|"Yes"| H["Cellular Layout"]
  G -->|"No"| I["Process Layout"]

Worked Example: Nabil Bank’s Branch Design Nabil Bank uses a hybrid process/product layout in its branches:

1. Process Layout: Teller counters (general banking), loan processing desks, and ATM areas are grouped by function.
2. Product Layout: High-frequency services (e.g., cash deposits) follow a linear flow to reduce wait times.
   • Key Insight: The layout prioritizes customer flow (e.g., ATMs near entrances) and employee efficiency (loan officers in quiet zones).
   • Cost Impact: Reduces idle time by 20% (source: Nabil Bank’s 2022 efficiency report).

3. Layout Design Principles

Regardless of layout type, follow these universal principles to optimize efficiency:

1. Minimize Material Handling: Reduce movement of people/materials (e.g., place heavy items near production).
2. Balance Workload: Avoid bottlenecks (e.g., in a product layout, ensure each station has equal task time).
3. Flexibility: Design for future changes (e.g., modular equipment in cellular layouts).
4. Safety and Ergonomics: Comply with OSHA standards (e.g., proper lighting, machine guarding).
5. Environmental Considerations: Use eco-friendly materials (e.g., solar-powered warehouses like Daraz’s).

Visual Tool: Spaghetti Diagram A spaghetti diagram maps employee/material movement to identify inefficiencies. Example for a Nepali tailor shop:

• Observation: If fabric is moved back and forth between stations, relocate cutting tables closer to sewing machines.

4. Advanced Topics: Specialized Layouts and Technologies

A. Hybrid Layouts

Combine layouts to exploit strengths. Example:

• Toyota’s Jidoka Layout: Mixes product and cellular layouts with automated error detection (e.g., sensors stop lines if a defect is found).

B. Lean Layouts

Eliminate waste (muda) using:

• 5S Methodology: Sort, Set in order, Shine, Standardize, Sustain.
• Kanban Systems: Visual signals (e.g., colored cards) to trigger replenishment (used by Daraz’s warehouses).

C. Automated Guided Vehicles (AGVs)

Used in mass/continuous processes (e.g., NTC’s automated inventory tracking in substations).

In the Real World

1. Daraz’s Warehouse Layout

   • Process Used: Hybrid batch (for custom orders) and product layout (for bulk items).
   • How It Works: AGVs transport high-demand items (e.g., groceries) via conveyor belts, while human pickers handle niche products. The layout reduces order fulfillment time by 30% compared to traditional warehouses.
   • Key Idea: Zone-based layouts minimize cross-traffic.

2. Nabil Bank’s ATM Network

   • Process Used: Product layout for ATMs (linear flow: card insertion → PIN entry → transaction selection).
   • Why It Matters: Standardized layout ensures 24/7 reliability and reduces training time for maintenance staff.
   • Trade-off: Low customization (no human teller interaction) but ultra-fast transactions.

3. Himalayan Java’s Coffee Processing

   • Process Used: Continuous process for roasting/grinding, fixed-position for drying beans on plantations.
   • Real Impact: Fixed-position layout allows farmers to dry beans under optimal sunlight, improving quality. Continuous roasting cuts costs by 15% per kg.

Case Study: Chaudhary Group’s Factory Optimization

Challenge: Chaudhary Group’s Bhatbhateni Industries (textile manufacturer) faced high setup times and inefficient material flow. Solution:

1. Process Change: Shifted from batch to cellular layout for fabric dyeing.
2. Layout Redesign:
   • Grouped dyeing, washing, and finishing machines into U-shaped cells.
   • Placed raw material inputs near the start of each cell.
3. Result:
   • Setup time reduced by 40% (from 2 hours to 1.2 hours per batch).
   • Waste reduced by 25% (less fabric damage during handling).
   • Lesson: Cellular layouts work even for moderate-volume products if teams are cross-trained.

Exam Tip

What Examiners Look For

1. Definitions with Examples:

   • Always pair terms (e.g., "product layout") with a Nepali example (e.g., "Ncell’s phone assembly line").
   • Avoid: Generic examples like "car manufacturing" without specifying the company.

2. Trade-off Analysis:

   • Questions often ask: "Why did Company X choose [layout/process]?"
   • Structure Your Answer:
     1. State the process/layout chosen.
     2. Link it to volume, customization, or cost (use the trade-off table).
     3. Give a real-world parallel (e.g., "Like Daraz’s batch processing for books").

3. Diagrams:

   • Draw a simple layout sketch (even in exams) to explain:
     • Flow of materials (arrows).
     • Machine/group placement.
   • Example Prompt: "Design a layout for a bakery producing 500 loaves/day with 10% custom orders."
     • Your Answer: Use a hybrid process/product layout with:
       • A dedicated dough-mixing line (product layout for bulk).
       • A separate custom-order station (process layout).

4. Numerical Problems:

   • Common Questions:
     • Calculate setup time savings after layout change.
     • Determine optimal batch size using the Economic Order Quantity (EOQ) model (though EOQ is Unit 7, layout decisions often tie to batch sizes).
   • Worked Example:

     A factory currently uses a process layout with 50m of material movement per batch. A product layout reduces this to 20m. If labor costs ₹50/hour and setup takes 2 hours, calculate the cost savings per batch. Solution:

     • Old movement: 50m × ₹X/m (assume ₹1/m) = ₹50.
     • New movement: 20m × ₹1 = ₹20.
     • Labor saved: 2 hours × ₹50 = ₹100.
     • Total savings per batch = ₹120.

5. Shortcomings of Layouts:

   • Always mention one disadvantage of the layout you discuss. Example:
     • "While product layouts reduce handling costs, they lack flexibility for product changes (e.g., Ncell cannot easily switch phone models)."

Model Answer Snippet for PU Exams

Question: "Discuss the factors influencing process selection for a company manufacturing customized furniture in Nepal. Suggest an appropriate process and layout, justifying your choice."

Answer: The process selection for a customized furniture manufacturer in Nepal depends on:

1. Low volume, high customization: Each order is unique (e.g., Kathmandu’s bespoke wooden chairs).
2. High setup flexibility: Tools must adapt to different designs (e.g., carving, staining).
3. Skilled labor: Artisans require general-purpose machines (e.g., lathes, sanders).

Recommended Process: Job Shop Process

• Why:
  • Handles one-of-a-kind orders (e.g., wedding chairs with intricate carvings).
  • Uses general-purpose equipment (e.g., hand tools, CNC mills).
  • Example: Sano Thimi furniture workshops in Bhaktapur.

Recommended Layout: Process Layout (Functional Layout)

• Design:

  flowchart LR
    A["Cutting Station\n(Shears, saws)"] --> B["Carving Station\n(Hand tools)"]
    C["Assembly Station\n(Screws, glue)"] --> D["Finishing Station\n(Paint, varnish)"]
    B --> C

• Advantages:
  • Artisans can move between stations as needed.
  • Minimizes material handling (wood stays in one place).
• Disadvantage: Longer lead times (e.g., 2 weeks vs. 3 days for mass-produced furniture).

Trade-off: If the company scales to 500 units/month, it should shift to a batch process with a cellular layout to reduce costs.

Final Tip: Always relate theory to Nepal. Examiners reward answers that use local companies (Daraz, Nabil Bank, Himalayan Java) or everyday scenarios (traffic routes in Kathmandu as a "process layout" analogy).