Control

In the context of quality, "Control" refers to the process of ensuring that activities conform to established standards and plans. It's about monitoring performance, comparing it against goals, and taking action to correct deviations. Quality Control, therefore, is the application of this control process specifically to maintain and achieve desired quality levels.

The Universal Control Process:

This fundamental process applies to controlling any aspect of operations, including quality. It involves a sequence of steps:

1. Choose the Control Subject: Identify what characteristic or performance aspect needs to be controlled (e.g., dimension of a part, purity of a chemical, call answer time).
2. Establish the Standard: Define the target value or acceptable range for the control subject (e.g., length = 50 +/- 0.1 mm, purity >= 99.5%, answer time < 15 seconds). This standard is often based on design specifications, customer requirements, or process capability.
3. Develop a Measurement Method: Determine how the control subject will be measured (unit of measure) and select the appropriate sensing device or procedure (e.g., use a calibrated caliper, perform chemical analysis, use call logging software).
4. Measure Actual Performance: Collect data on the control subject using the defined method.
5. Compare Actual vs. Standard: Analyze the measured performance against the established standard. Is there a deviation? Is it significant?
6. Take Corrective Action: If a significant deviation exists, investigate the cause and implement actions to bring the performance back into conformance with the standard. This might involve adjusting a machine, retraining an operator, changing materials, or revising the process itself.

Need for Controlling Quality:

Implementing quality control processes is essential because, in its absence:

• Lack of Benchmarks: There is no objective way to judge if quality standards are being met.
• Inconsistency: Product or service quality can vary widely, leading to unpredictability for customers.
• Customer Dissatisfaction: Inconsistent or poor quality leads to complaints, returns, warranty claims, and lost loyalty.
• Increased Costs: Higher rates of scrap, rework, and wasted resources occur when defects are not controlled.
• Reduced Reliability: Products may fail prematurely or services may not perform as expected.
• Production Disruptions: Quality problems can halt production lines and disrupt schedules.
• Loss of Competitiveness: Competitors offering consistently higher quality will gain market share.

Indian Example: A manufacturer of electrical switches in India, like Havells or Anchor, needs tight control over the dimensions and assembly of switch components.

1. Control Subject: Gap between electrical contacts when the switch is off.
2. Standard: A specific minimum gap (e.g., 3 +/- 0.1 mm) for safety.
3. Measurement: Use of specialized gauges or vision systems on the assembly line.
4. Measure: Check the gap on samples or 100% of switches.
5. Compare: Identify any switches failing the minimum gap standard.
6. Action: Stop the assembly machine, investigate the cause (e.g., worn tool, incorrect setting), fix the issue, and potentially rework or scrap affected switches. This control process is vital for product safety and regulatory compliance.

Control is the mechanism that keeps processes on track and ensures that planned quality standards are actually achieved in practice.