Process Quality Control (Process Quality Control) PQC, the abbreviation of process control. PQC refers to those results that are within the tolerance, no matter where they are, close to the target value or not, there is no significant change in customer satisfaction, but once the measurement result is outside the specification, then customer satisfaction will drop sharply like a parabola.

First: Confirm the first product of each batch when opening or replacing products, and provide the production department with the standards for product production. The first inspection has notification and preventive functions;

Second: The inspection requirements for online products should be controlled according to the requirements of the first sample, which means that all products must meet the requirements of the first sample during formal production, and incoming material inspection must be done before the launch. This is to inspect the products that are about to be produced. The raw materials of the product are checked to confirm the correctness of the materials.

Extended information

Process quality control that relies on product inspection has the following differences:

1. The focus and focus of control are different. Inspection control only focuses on the results of the process, weakening or abandoning the control of process inputs; while closed-loop quality control first focuses on the control of process inputs.

2. The purposes of product testing are different. In inspection control, the purpose of inspecting products is to determine whether the product is qualified; in closed-loop process quality control, the purpose of inspecting products is to understand the changing trends of the process.

3. The comparison objects of product test values ??are different. In inspection control, the comparison object of the product's detection value is the product's tolerance; in closed-loop process quality control, the comparison object of the product's detection value is first of all the target value of the product characteristics. If it is a two-way tolerance, it should be compared with the intermediate tolerance.

4. The stability of process quality will be very different. Under the guiding ideology of relying on product testing, the study of the influence relationship between process input and output is inevitably abandoned, the analysis of the reasonable range of process input is abandoned, and the control of process input is weakened or ignored.

Therefore, the process is unstable; with closed-loop quality control based on control input, the stability of the process can be guaranteed, and product characteristics are often concentrated in a stable distribution of intermediate tolerances.

5. The frequency of product testing will vary greatly. If the process is stable, random inspections can be used to check. But if the process is unstable, 100% detection must be used.

6. Quality costs are different. Inspection-based process quality control increases inspection costs because of the need for 100% inspection, increases scrap costs because of poor process stability, and also because the product characteristics of parts and components often fluctuate near the extreme tolerances, making it easy to create a successful product. Functional impairment leads to frequent customer complaints.

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