---
id: "ctq-management-en"
title: "CTQ Critical Quality Characteristics Management | Zhongde Precision"
description: "Identify CTQs from product function and failure risks, then deploy them through material, forming, machining, finishing, assembly and final validation."
source: "/en/quality/ctq-management"
language: "en"
generated: true
---

# Critical Quality Characteristics Should Be Controlled Before Final Inspection

Function-Based CTQ Identification · Process Control · Measurement & Traceability

Conventional inspection determines whether a finished part is acceptable. CTQ management begins with product function, assembly relationships and failure risks to identify the characteristics that truly determine performance and reliability. Zhongde’s integrated manufacturing system carries the same CTQ through material, forming, precision machining, surface finishing, assembly and final validation.

- Identify CTQs from product function and failure risks
- Translate critical requirements into process controls
- Link drawings, process results, inspection and production lots

## Key Figures

- Function-Based · Defined from product performance, assembly and failure risk
- Risk Prevention · Critical characteristics defined before manufacturing
- Process Control · CTQs deployed to related manufacturing and inspection steps
- Traceable Records · Revisions, process results and production lots remain linked

## 01. Identify the CTQs That Truly Determine Product Quality

A drawing may contain more than one hundred dimensions, tolerances and technical requirements, but they do not affect product function equally. CTQs are the limited number of characteristics that directly influence assembly, performance, reliability or special customer requirements.

CTQ management does not reduce control of other requirements. All requirements remain compliant with the drawing, while the limited characteristics that determine function and reliability receive a higher level of control.

### A Drawing May Contain 100+ Requirements

Every requirement must still be met, while only a limited number directly determine function, assembly and reliability.

### How CTQs Are Identified and Managed

#### 01. Understand Product Function and Assembly

Clarify the part’s role, mating interfaces, loading conditions and operating relationships.

#### 02. Evaluate Failure Impact and Process Risk

Assess how deviations affect assembly, performance and reliability against process capability.

#### 03. Define CTQs and Control Standards

Specify critical dimensions, geometry, surfaces, materials or functional acceptance criteria.

#### 04. Deploy Process, Measurement and Records

Assign process controls, measurement methods, inspection frequency and traceable records.

### CTQ Categories

#### Critical Dimensions and Geometry

Diameter, position, flatness, concentricity and mating dimensions

#### Critical Surfaces and Process Results

Roughness, coating thickness, cleanliness, hardness and heat-treatment condition

#### Critical Assembly and Functional Results

Torque, press-fit depth, leak rate, rotational condition and functional testing

## 02. CTQ Management Is Not Treating Every Dimension as Equally Critical

Conventional final inspection focuses on whether the finished product is acceptable. CTQ management starts from product function, assembly relationships and failure risks to identify the characteristics that truly determine performance and reliability.

Conventional inspection answers “Is the product acceptable?” CTQ management answers “Which characteristics determine whether the product works properly, and how can loss of control be prevented?”

### Conventional Final Inspection / Average Control

#### Process Steps

##### Manufacture to Drawing

##### Final Inspection

##### Pass / Fail

##### Rework / Late Risk Exposure

### CTQ Management

#### Process Steps

##### Product Function

##### Failure Risk

##### Identify CTQs

##### Process Control & Records

### Engineering Benefits

#### Earlier Risk Detection

#### Less Batch Rework

#### Lower Functional Failure Risk

#### More Rational Quality Cost Allocation

## 03. One Integrated Factory Keeps the Same CTQ Connected Across Processes

A single CTQ is often influenced by several upstream and downstream operations. Zhongde maintains consistent drawings, datums, compensation relationships, process data and feedback within one factory, carrying the CTQ from engineering review through final validation.

### Unified Control Line

#### Engineering Items

- Controlled Drawing Revision
- Unified CTQ Standard
- Common Datums & Compensation

### One CTQ: Bearing Bore and Shaft-System Fit

#### Forming

Control blank deformation, machining allowance and datum stability

#### Precision Machining

Control bore size, roundness, concentricity and position

#### Surface Finishing

Manage coating allowance, masking and treatment deformation

#### Assembly

Confirm press force, insertion depth and fit condition

#### Final Validation

Verify rotational resistance, runout and operating condition

### Records & Feedback Line

#### Engineering Items

- First-Article Results
- Process Records
- Nonconformance Feedback
- Lot Traceability

### Engineering Comparison

#### Segmented Multi-Supplier Production

##### Engineering Items

- Drawing, datum and CTQ information can become disconnected
- Downstream issues require repeated cross-company communication
- Quality records and responsibility boundaries remain fragmented

#### Zhongde Integrated Factory

##### Engineering Items

- The same CTQ remains connected across related processes
- Downstream issues feed directly back to upstream operations
- Process results, issues and production lots remain linked

### Engineering Benefits

#### No CTQ Handover Loss

#### Faster Issue Feedback

#### Fewer Local-Pass / System-Fail Cases

#### Faster Affected-Lot Identification