Learning Goal: Conduct a basic time study and calculate the Standard Minute Value (SMV) for a garment operation.

Complete Lesson Content:
SMV is the time a qualified operator should take to perform a specific task at a standard pace, including allowances for rest and personal needs. Time study involves observing and timing an operation, rating the operator’s pace, and normalizing the time. The formula: Observed Time × Rating / 100 = Normal Time. SMV = Normal Time + Allowances (usually 15–20%). SMVs are used for costing, line balancing, and incentive setting.

Definitions:

  • Rating – assessing the operator’s speed relative to a standard pace (100% = standard).
  • Allowances – extra time for fatigue, machine stoppage, and personal needs.

Step‑by‑step Explanation:

  1. Select an experienced operator working at a consistent pace.
  2. Record the time for 10–20 cycles using a stopwatch.
  3. Calculate the average observed time.
  4. Rate the operator (e.g., 90% if slightly slower than standard).
  5. Normal time = Average Observed Time × (Rating / 100).
  6. Add allowances: SMV = Normal Time × (1 + Allowance %). Example: Normal time 0.50 min, allowance 20% => SMV = 0.60 min.

Best Practices: Take a video and analyse later for more accuracy; involve the operator to get consent and reduce anxiety.

Common Mistakes: Rating too high or low due to inexperience; using one very fast operator without rating leads to an unachievable SMV for the line.

Real Industry Example: A large manufacturer uses pre‑determined motion time systems (PMTS) like GSD (General Sewing Data) to set SMVs without rating bias, but these are expensive.

Mini Case Study: A factory set SMV based on the supervisor’s estimate, not actual study. Operators couldn’t meet the target, morale dropped. After a proper time study and SMV recalculation, the target became fair, and efficiency improved.

Practical Activity: Use the provided video (or simulate) of a stitching operation, record cycle times, rate the operator, and calculate the SMV with 18% allowance.

Assignment: Conduct a time study on a simple household task (like folding a t‑shirt). Document your process, calculate normal time and SMV, and discuss challenges.

Lesson Summary: SMV is the foundation of industrial engineering; accurate measurement leads to realistic targets.

Key Takeaways:

  • Time study + rating = normal time.
  • Add allowances for SMV.
  • Fair targets motivate.
PreviousNext