Quality Control

Quality control defines the processes, procedures, and standards that ensure products and services meet quality requirements. This guide covers setting up and managing quality control.

Overview

Quality control enables you to:

• Define quality control plans
• Set acceptance criteria
• Configure sampling procedures
• Monitor process quality
• Track quality metrics
• Ensure compliance

Accessing Quality Control

Navigate to Quality → Control Plans or Settings → Quality → Control.

Understanding Quality Control

Control Plan Components

Component	Description
Control Point	Where quality is checked
Characteristic	What is measured
Specification	Required standard
Method	How to check
Frequency	When to check
Reaction Plan	What to do if fail

Control Types

Type	Description	Application
Prevention	Stop defects	Process design
Detection	Find defects	Inspection
Correction	Fix defects	Rework

Quality Levels

Level	Description
Critical	Safety/regulatory
Major	Function affected
Minor	Appearance only
Cosmetic	Preference only

Setting Up Quality Control

Creating Control Plans

1. Go to Quality → Control Plans
2. Click New Control Plan
3. Enter details:

Field	Description
Name	Plan identifier
Product	What it applies to
Version	Revision number
Status	Draft/Active

4. Add control points
5. Define characteristics
6. Set specifications
7. Activate plan

Control Point Setup

For each control point:

• Location in process
• Responsible person/team
• Equipment required
• Documentation needed

How-To Guides

How to Create Quality Control Plans

Plan Structure

Control Plan: CP-001
Product: Widget Assembly

Control Point 1: Incoming Material
├─ Check: Material certificate
├─ Check: Visual inspection
└─ Check: Dimensions

Control Point 2: Assembly
├─ Check: Component fit
├─ Check: Torque values
└─ Check: Alignment

Control Point 3: Final
├─ Check: Function test
├─ Check: Appearance
└─ Check: Packaging

Creating the Plan

1. Define scope:

   • Products covered
   • Processes included
   • Stages applicable

2. Identify control points:

   • Where quality matters
   • Critical operations
   • High-risk areas

3. Define characteristics:

   • What to measure
   • Standards to meet
   • Tolerance limits

4. Specify methods:

   • How to check
   • Equipment needed
   • Sample size

5. Set frequency:

   • Every piece
   • Sampling
   • Periodic

6. Document reaction:

   • What if fail
   • Escalation path
   • Corrective action

How to Define Acceptance Criteria

Criteria Types

Type	Example
Attribute	Pass/Fail, Go/No-Go
Variable	Measurement ± tolerance
Visual	Reference standard
Performance	Test requirements

Setting Specifications

Characteristic: Length
Nominal: 100 mm
Tolerance: ±0.5 mm
LSL: 99.5 mm
USL: 100.5 mm

Pass: 99.5 ≤ Actual ≤ 100.5
Fail: Outside limits

AQL Acceptance

Lot Size	Sample	Accept	Reject
2-8	2	0	1
9-15	3	0	1
16-25	5	0	1
26-50	8	0	1
51-90	13	1	2

How to Configure Sampling Procedures

Sampling Plan Setup

1. Go to Settings → Quality → Sampling
2. Select sampling type:
   • Single sampling
   • Double sampling
   • Sequential sampling
3. Configure parameters:
   • Lot size ranges
   • Sample sizes
   • Accept/reject numbers
4. Save plan

Sampling Levels

Level	Rigor	Use When
Tightened	More samples	Quality issues
Normal	Standard	Stable quality
Reduced	Fewer samples	Proven quality

Switching Rules

Normal → Tightened:
  2 of 5 lots rejected

Tightened → Normal:
  5 consecutive lots accepted

Normal → Reduced:
  10 consecutive lots accepted
  AND production stable

How to Monitor Process Quality

SPC (Statistical Process Control)

Monitor process with control charts:

• X-bar chart (average)
• R chart (range)
• p chart (proportion defective)
• c chart (defects per unit)

Control Limits

UCL = X̄ + 3σ (Upper Control Limit)
CL = X̄ (Center Line)
LCL = X̄ - 3σ (Lower Control Limit)

Process Capability

Index	Formula	Good Value
Cp	(USL-LSL)/6σ	>1.33
Cpk	Min(Cpu, Cpl)	>1.33
Pp	Process performance	>1.67

How to Implement Control Charts

Setting Up Charts

1. Go to Quality → SPC
2. Select characteristic
3. Choose chart type
4. Configure limits:
   • Specification limits
   • Control limits
   • Warning limits
5. Enable monitoring

Reading Charts

Pattern	Indicates
Points within limits	In control
Point outside limit	Out of control
Run of 7	Process shift
Trend	Gradual change
Cycle	Periodic variation

Taking Action

When out of control:

1. Stop process (if critical)
2. Investigate cause
3. Implement correction
4. Verify correction
5. Resume with monitoring

How to Manage Control Documentation

Required Documents

Document	Purpose
Control Plan	Master control document
Work Instructions	How to perform checks
Inspection Records	Results documentation
Calibration Records	Equipment verification

Document Control

• Version management
• Approval workflow
• Distribution control
• Retention policy

How to Handle Process Changes

Change Process

1. Identify change:
   • Process modification
   • Material change
   • Equipment update
2. Evaluate impact on quality
3. Update control plan
4. Validate effectiveness
5. Train personnel
6. Implement change
7. Monitor results

Validation Requirements

After changes:

• Initial capability study
• First article inspection
• Process validation
• Control plan update

Advanced Features

Automated Monitoring

Real-time quality tracking:

• Sensor integration
• Automatic data collection
• Alert generation
• Dashboard display

Supplier Quality Control

Extend to suppliers:

• Supplier control plans
• Incoming inspection
• Performance tracking
• Quality agreements

Risk-Based Control

Focus on critical areas:

• FMEA integration
• Risk prioritization
• Control allocation
• Review frequency

Compliance Management

Regulatory requirements:

• Standard compliance (ISO, etc.)
• Audit preparation
• Documentation requirements
• Certification support

Best Practices

📋 Planning

• Comprehensive coverage
• Clear specifications
• Appropriate sampling
• Documented procedures

🔍 Execution

• Consistent application
• Calibrated equipment
• Trained personnel
• Timely recording

📊 Analysis

• Regular review
• Trend analysis
• Capability studies
• Continuous improvement

📝 Documentation

• Complete records
• Version control
• Audit trail
• Retention compliance

Configuration

Control Settings

Navigate to Settings → Quality → Control:

• Control Levels - Severity definitions
• Sampling Tables - AQL tables
• SPC Parameters - Chart settings
• Alert Thresholds - Warning levels

Plan Settings

• Templates - Standard plans
• Characteristics - Standard checks
• Methods - Test procedures
• Equipment - Measurement devices

Integration Settings

• Production - Process linking
• Inventory - Status integration
• Documents - Record management
• Alerts - Notification rules

Troubleshooting

Common Issues

Control chart showing out of control

• Verify measurement accuracy
• Check for special causes
• Review process stability
• Investigate and correct

Capability below target

• Review specification limits
• Analyze process variation
• Identify improvement opportunities
• Implement corrections

Plan not triggering inspection

• Check activation status
• Verify trigger conditions
• Review workflow rules
• Check integration

Data not collecting

• Verify equipment connection
• Check data entry
• Review system settings
• Test connectivity

Next Steps

Learn about Non-Conformance Management to handle quality issues and corrective actions.