Product Quality and Process Control
ITEM 5: Product Specifications and Quality
Products
Products are tangible assets designed to meet specific consumer needs. This includes packaging, protective measures, and distribution tools from manufacturing to end-user.
Product specifications should include:
- Product Title
- Product Applications
- Conditions
- Physical Characteristics
- Reliability Features
- Maintainability Characteristics
- Acceptance Criteria
- Packing and Protection
- Special Information and Servicing
Quality Control
Quality control ensures products meet specifications through a seven-stage process:
- Define the control objective.
- Establish standard specifications.
- Select a unit of measurement.
- Choose a measuring instrument.
- Measure using the chosen unit.
- Compare actual and standard values.
- Address any discrepancies.
Inspection
Inspection evaluates product quality through visual checks, measurements, or lab tests. Types of inspection include:
- Inspection of individual product units.
- Inspection of samples from a larger batch.
Inspection intensity varies:
- No inspection
- Small sample inspection
- Large sample inspection
- 100% inspection
Sampling inspection involves randomly evaluating a portion of a batch to determine acceptance or rejection of the entire batch.
Self-Inspection
Typically, inspectors, not the workers performing the operations, conduct inspections.
Quality in Warehouse and Shipping
Maintaining product quality extends beyond the factory. Proper handling, storage, and shipping are crucial for preserving quality until the product reaches its final destination.
ITEM 6: Process Control
Process Definition
A process is a series of actions that add value to input from a supplier to create output for a client.
Statistical Process Control
This method focuses on preventing defects by intervening in the process before they occur.
Histograms
A histogram visually represents the frequency distribution of values.
Process Variability
All processes have inherent variability. There are two types:
- Assignable causes: Identifiable and repairable.
- Random causes: Can be reduced but not eliminated.
Control Charts
Control charts track a characteristic’s evolution over time, representing product or process quality measured or calculated from a sample.