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Quality control process

* select control topics;(subject selection according to actual order requirements and problems in the company's operation process)

* select measurement units - conduct measurement;(our company establishes, plans and quantifies the selected control subjects)

* establish implementation standards;(establish applicable standards based on quantitative measurement data)

* actual operation;(control and implement the problem and make improvement)

* explain differences (actual and standard differences);

* take action on differences;(maintain and consolidate improvements)

Quality control details

1. QC control method

Our company adopts the following methods to control the quality:


(2)Cause and effect diagram;


(4)Scatter diagram,

(5)Layered method;


(7) Control chart.

Quality control inspection method

1.Total inspection: all products or materials submitted for inspection are inspected without omission.

Apply to the following situations:

A. Low volume, simple inspection and low cost;

B. The requirements of the products must be qualified;

C. Depending on a small number of nonconforming products, it can have a fatal impact.

2. Sampling inspection: select some individuals from all individuals of a batch of products for inspection, and judge whether the whole batch of products is qualified according to the test results of samples. Apply to the

following situations:

A. Destructive testing is required for product performance testing;(such as the 100 case test of shell spraying, the stretching test of waterproof rubber rings, the test of product reliability verification, etc.)

B. The batch is too large for full inspection;

C. Longer inspection time and higher inspection costs are required;(luminous Angle test, color temperature test, optical flux test, and electrical parameters and performance test)

D. a certain degree of defective goods are allowed.

Related terms used in parliamentary sampling inspection:

A. Inspection batch: the same products are grouped together for sample inspection; Generally speaking, a production batch is a inspection batch. A production batch can be divided into several inspection batches, but a test batch cannot contain multiple production batches, nor can it be combined at will.

B. Batch: the number of units in the batch;(again, there are slight differences in some parameters between different batches of products, such as light source color and radiator color. We will separate the products according to the batch to achieve the highest consistency of the products)

C. Sampling number: the number of products extracted from the batch;(established according to my AQL sampling standard)

D. Unqualified judgment number (Re) : the abbreviation for Refuse is Refuse;

E. qualified determination number (Ac) : Accept is short for receiving;

F. Acceptable Quality Level (AQL) : short for Acceptable Quality Level. The rate of acceptable nonconforming product will be determined according to its criteria.

3. Determination of sampling plan: our company conducts sampling design according to the sampling procedure and sampling table of batch inspection counting in accordance with the national standard GB2828.The specific application steps are as follows:

(1) choose the AQL inspection level: general inspection level points Ⅰ, Ⅱ, Ⅲ;Special inspection level points, S – 1,S - 2, S - 3, S - 4 without special requirement by the client, using the average Ⅱ.


(2)As AQL is the main basis for selecting the sampling scheme, our company will confirm its AQL standard by communicating with the customer. AQL 4.0 is commonly used

(3)The number of samples to be determined is the number of samples.

(4) Sample selection scheme type: select appropriate sampling criteria according to different customer requirements and product characteristics, such as a normal sampling scheme, strict sampling scheme, or multiple sampling scheme.

(5)Run check table determines the number of qualified criteria (AC) and non-qualified criteria (Re).

Quality control operation control

1. Incoming (cargo) inspection (IQC) : it is the primary control point of our company to prevent unqualified materials from entering the production process. Incoming Quality Control Reporting materials inspection items and methods:

A appearance: visual, hand feel and comparative samples are generally used for verification.

B size: generally verified by calipers, micrometers and steel ruler, etc.

C characteristics: mainly including physical, chemical and mechanical properties, which are generally verified by testing instruments and specific methods.

D Methods: a full inspection and b sampling inspection

E The processing of the test results:


b.refusal (i.e. return of goods);

c.concession acceptance;

d.Complete inspection (return of rejected products)

e.Reinspection after rework

F Standards for materials and purchased parts, procedures for incoming inspection and test control, rules for physical and chemical inspection, etc.

2. Production process inspection (IPQC) : Quality Control of production activities from material warehousing to finished product warehousing, i.e. In-process Quality Control. Also, the method of direct proportion test is as follows:

A. The first part is combined with self-inspection, mutual inspection and special inspection;

B. Process control is combined with sampling inspection and patrol inspection;

C. Centralized inspection of multiple processes;

D. Inspection by process;

E. inspection after completion of products;

F. Combination of sampling and full inspection;

3. Parliamentary process quality control (IPQC) : it is a second barrier to quality control to conduct itinerant inspection of the production process.

A. first piece inspection; Two working days before the product is put into production, the growth department will collect the first sample of the order, check the materials and conduct self-inspection, and then send the finished product to quality QC for confirmation.

B. Material verification; QC checked the order and tested to ensure that the material and performance of the product are consistent with the order requirements.

C. Inspection: ensure the proper inspection time and frequency, and strictly follow the inspection standards or operation instructions. Including inspection of product quality, process regulations, machine operating parameters, material placement, marking, environment, etc.

D. inspection records shall be filled in truthfully.

4. Test of product quality (FQC) : it refers to the quality verification after the completion of the product to determine whether the batch of products can flow into the next process, which belongs to the designated inspection or acceptance inspection. Mainly control the aging and waterproof test of the product to ensure the quality of the product.

A. Inspection items: appearance, size, electrical and optical properties, etc.

B. Inspection method: sampling inspection is generally adopted;

C. non-conforming treatment; If the process appears, FQC will promptly notify the PE engineer to judge of bad products, such as for self-judgment, will make timely processing, such as self cannot make judgments, to give timely feedback to leadership, and make the corresponding processing in a timely manner.

D. records; Strict  and true records are required

Standards of work instruction, procedure inspection standards, process inspection and test procedures, order standards, etc.

5. Final inspection control: delivery inspection of finished products.(Outgoing Q.C)

6. Feedback and treatment of quality abnormalities:

If it can be determined by itself, it shall inform the operator or workshop directly to deal with it immediately.

If the user can't make a decision by himself, he/she shall submit the defective sample to the supervisor for confirmation, and then inform him/her to correct or deal with it.

Signal should record the abnormal situation truthfully;

Verification of corrective or improvement measures, establishment of responsible persons, and follow-up of handling effects;

Inspection of semi-finished products and finished products shall be clearly marked in status and monitored by relevant departments (production and warehouse) for separate storage.

7. Quality record: provide objective evidence for completed quality work activities and results. It must be accurate, timely, clearly written, complete and stamped with inspection seal or signature. Also do this: organize, file and store in the right environment in a timely manner to facilitate order tracking.