Production Systems & Process Analysis: Types, Models & Optimization

TAKEAWAYS:

• Three core production systems (continuous, intermittent, batch) differ by volume, flexibility, and cost—choose based on demand predictability and product variety.
• Transformation processes convert inputs (labor, materials, information) into outputs via operations like assembly, repair, or data processing (e.g., Daraz’s order fulfillment).
• Process analysis tools (flowcharts, value stream mapping) reveal bottlenecks and waste (e.g., NTC’s call-center queue delays).
• ABC inventory classification prioritizes high-value items (A-items) to minimize holding costs (used by Himalayan Java for coffee beans).
• Economic Order Quantity (EOQ) balances ordering costs vs. holding costs—critical for perishable goods (e.g., Pathao’s bike inventory).
• Service process matrix links service type (mass vs. professional) to process design (e.g., eSewa’s automated vs. bank-teller transactions).

1. Production Systems: Types and Characteristics

Production systems classify how businesses manufacture or deliver services. The choice depends on volume, variety, and customization needs.

A. Continuous Production System

Definition: A system where production runs non-stop with minimal interruptions, using automated machinery for high-volume, standardized outputs (e.g., oil refineries, soft drink bottling).

Key Features:

• High volume, low variety (e.g., Coca-Cola plants).
• Automated with minimal human intervention.
• Fixed sequence of operations (e.g., cement production).
• High initial investment but low per-unit cost.

Example in Nepal:

• Nepal Oil Corporation (NOC) refinery in Chitwan uses continuous production for fuel refining.
• Himalayan Java’s coffee roasting (for bulk orders) employs semi-continuous lines.

Advantages/Disadvantages:

B. Intermittent Production System

Definition: Produces small batches or customized items in response to orders. Flexible but less efficient for mass production (e.g., furniture making, car manufacturing).

Key Features:

• Low volume, high variety (e.g., tailor-made suits).
• Job shop or batch processing (e.g., printing press for custom books).
• High flexibility but higher per-unit cost.
• Used in service sectors (e.g., eSewa’s one-time bill payments).

Example in Nepal:

• Hetauda Kapada Udhyog Ltd. (textiles) uses intermittent systems for custom fabric orders.
• Computer Services Limited (CSL) repairs PCs in small batches per customer request.

Mermaid Diagram: Production System Spectrum

flowchart LR
  A[Continuous
High Volume
Low Variety
(e.g., Nepal Oil Corp refinery)] -->|Low Volume
High Variety| B["Intermittent"]
  B -->|Medium Volume
Medium Variety| C[Batch
(e.g., Nepal Pharmaceuticals)]
  C -->|Low Volume
High Variety| D[Job Shop
(e.g., Hetauda Kapada Udhyog custom orders)]

C. Batch Production System

Hybrid of continuous and intermittent:

• Produces identical items in groups (e.g., bakery bread batches, Daraz’s bulk electronics orders).
• Balances flexibility and efficiency.

Example:

• Nabil Bank’s checkbook printing runs in batches for different customer tiers.

2. Transformation Process: Inputs → Outputs

Definition: The core of service operations—converting inputs (resources) into outputs (products/services) via operations.

Key Components:

1. Inputs:
   • Labor (e.g., NTC technicians).
   • Materials (e.g., raw steel for Daraz’s furniture).
   • Information (e.g., customer data for eSewa).
   • Facilities (e.g., Pathao’s bike depots).
2. Transformation Process:
   • Operations (assembly, repair, data processing).
   • Flow (linear, networked, or project-based).
3. Outputs:
   • Tangible (e.g., a smartphone from BIROI).
   • Intangible (e.g., a WhatsApp call).

Example: Daraz’s Order Fulfillment

1. Input: Inventory (A-items like smartphones), labor, delivery vans.
2. Process:
   • Pick → Pack → Ship (automated sorting systems).
   • Real-time tracking via GPS.
3. Output: Delivered product + customer feedback.

Process Flowchart for Service Sector

flowchart TD
    A["Customer Request"] --> B{"Standardized?"}
    B -->|"Yes"| C["Automated Process<br/>(e.g., eSewa payment)"]
    B -->|"No"| D["Custom Process<br/>(e.g., bank loan approval)"]
    C --> E["Output: Service Delivered"]
    D --> F["Human Review<br/>→ Output"]

3. Process Analysis Tools

A. Flowcharting

Purpose: Visualize steps to identify bottlenecks or redundancies. Example: NTC’s Customer Complaint Process

• Problem: Complaints take 10 days due to manual paperwork.
• Solution: Automate Step 3 (IVR system like eSewa’s chatbot).

B. Value Stream Mapping (VSM)

Purpose: Map value-added vs. non-value-added steps (waste like waiting, overproduction). Example: Pathao’s Bike Maintenance

flowchart LR
  A["Bike Returned"] --> B[Manual Inspection
(2 hours)
(Waste: Overprocessing)]
  B --> C[Wait for Parts
(1 day)
(Waste: Waiting)]
  C --> D[Repair
(3 hours)]
  D --> E[Test Drive
(1 hour)]
  E --> F["Delivered"]
  "Waste Types:\n• Waiting (1 day)\n• Overprocessing (manual inspection)"

C. Bottleneck Analysis

Definition: The slowest step in a process limits throughput. Example: Kathmandu Traffic (Service Process)

• Bottleneck: Lack of signal synchronization at intersections.
• Solution: Adaptive traffic lights (like Singapore’s SCATS system).

4. Inventory Management in Production

A. ABC Classification

Prioritizes items by value and usage frequency.

Worked Example: Himalayan Java

• A-items: Arabica beans (80% of inventory value).
• Action: Use just-in-time (JIT) delivery to avoid spoilage.

B. Inventory Control Systems

1. Continuous Review (Q-system):
   • Trigger: Reorder when stock hits minimum level.
   • Example: Nabil Bank’s ATM cash replenishment.
2. Periodic Review (P-system):
   • Trigger: Fixed-time checks (e.g., monthly).
   • Example: NTC’s spare parts inventory.

EOQ Formula (for A-items): $$EOQ=\sqrt{\frac{2DS}{H}}$$

• $D$ = Annual demand (units)
• $S$ = Ordering cost (Rs.)
• $H$ = Holding cost per unit per year

Worked Example: Pathao’s Bike Inventory

• Demand (D): 50 bikes/month = 600/year.
• Ordering cost (S): Rs. 200 per order.
• Holding cost (H): Rs. 50/bike/year. $$EOQ=\sqrt{\frac{2\times 600\times 200}{50}}=\sqrt{4800}\approx 69\text{ bikes}$$ Recommendation: Order 69 bikes every 2 months to minimize costs.

5. Service Process Matrix

Links service type to process design (based on customization and interaction).

Example: eSewa vs. Bank Teller

• eSewa: Service Factory (automated, low interaction).
• Bank Teller: Service Shop (manual, high interaction).

In the Real World

1. Daraz’s Fulfillment Centers

   • Idea: Batch production + ABC inventory.
   • How: A-items (electronics) are stored in automated warehouses with real-time tracking, while C-items (packaging) use bulk ordering. Bottlenecks are identified via VSM to optimize picker routes.

2. NTC’s Customer Service

   • Idea: Service process matrix (Service Shop).
   • How: Uses IVR (Interactive Voice Response) for routine queries (mass service) but routes complex issues to human agents (professional service). Flowcharting revealed that 30% of calls were redundant due to unclear menu options—fixed by simplifying IVR paths.

3. Himalayan Java’s Coffee Supply Chain

   • Idea: Continuous review inventory + ABC classification.
   • How: Arabica beans (A-items) are ordered weekly via JIT to prevent spoilage, while packaging (C-items) is ordered monthly in bulk. EOQ analysis reduced holding costs by 22%.

Exam Tip

1. Case Studies (30% weight):

   • Structure: Use the SOAR method (Situation, Options, Action, Result).
   • Example Question: "BIROI’s CEO wants to reduce production delays. Analyze their intermittent system and suggest improvements."
     • Answer:
       • Situation: Intermittent system causes 3-day delays due to machine setup time.
       • Options:
         • Switch to batch production for similar models.
         • Invest in flexible machinery (e.g., CNC routers).
       • Action: Implement batch processing for smart home appliances (high volume) and keep intermittent for custom orders.
       • Result: Reduces setup time by 40%.

2. Definitions (20%):

   • Must-know terms:
     • Transformation process: "Conversion of inputs to outputs via operations."
     • Bottleneck: "The step that limits the entire process’s speed."
     • EOQ: "Optimal order quantity minimizing total inventory costs."

3. Diagrams (20%):

   • Always draw:
     • Flowcharts for processes (e.g., NTC complaints).
     • Service process matrix for service types.
     • ABC classification table with examples.

4. Calculations (15%):

   • EOQ, total cost analysis, or bottleneck time calculations.
   • Example: Given demand = 50 units/month, ordering cost = Rs. 100, holding cost = Rs. 2/unit/month, calculate EOQ and total annual cost.

5. Comparisons (15%):

   • Table format for:
     • Continuous vs. intermittent systems.
     • Q-system vs. P-system inventory.

Final Checklist Before Exam: ✅ Can you distinguish between continuous, intermittent, and batch systems with Nepali examples? ✅ Can you map a process (e.g., Pathao’s bike repair) and identify waste? ✅ Do you know how to apply EOQ to a real scenario (e.g., Daraz’s inventory)? ✅ Can you classify a service (e.g., eSewa) in the service process matrix?