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The first test, why is it so important?

In the design and production process of any product, there are often activities such as design changes, process changes, process adjustments, unplanned stoppages, conversions, and transfer lines. So, how to ensure that these activities will not affect the subsequent production quality? This requires the first inspection to be carried out during the verification phase of the operation preparation and after the shutdown. valve grinder

Definition of first article and first article inspection

Process change
During the production process, any one or more of the 5M1E (human, machine, material, method, ring, and test) production factors are changed, such as personnel changes, equipment adjustment and maintenance, refueling and replacement fixtures, and design changes. Stop the line and so on. valve grinder

first item
The first or the first few products processed by the production line at the beginning of each shift/production line production or after the process changes. For mass production, the “first piece” often refers to a certain number of samples.

First Article Inspection
The inspection of the first or the first few products processed by the production line at the beginning of each shift or after the process has been changed. The number of inspections can be set according to the requirements of different companies or customers. In general, at least 3-5 products that are continuously produced need to be inspected, and the follow-up products can be processed after passing the inspection. The first inspection must be strictly performed before any change in the equipment or manufacturing process and before each working shift starts processing. valve grinder

The purpose of the first inspection

The first inspection in the production process is mainly to prevent the products from appearing in batches in excess of quality, being repaired and scrapped. It is a means of controlling the production process of products in advance, an important method for quality control of product processes, and ensuring the quality of products. An effective and essential method to increase economic efficiency

The first inspection is to find the factors affecting the product quality in the production process as early as possible, and to prevent the defective batch or the rejection

After the first inspection, it can enter the formal production, mainly to prevent the occurrence of batch unqualified products.

Long-term practical experience proves that the first inspection system is an effective measure for early detection of problems and prevention of mass scrapping of products. Through the first inspection, it can be found that there are systemic reasons such as severe fixture wear or misalignment, poor measuring instrument accuracy, mistaken drawing, feeding or formula errors, etc., so corrective or improvement measures can be taken to prevent batches from failing. Qualified product occurs. valve grinder


Every work class begins

Change operator

Replace or adjust equipment, process equipment (including tool change or sharpening)

Change technical conditions, process methods, and process parameters (such as changing the roughness requirements, changing the borehole reaming to boring, changing the number of passes or speed in the NC program, etc.) valve grinder

After adopting new material or material substitute (such as material change during processing, etc.)

Replace or retest the bath solution (such as phosphating, nitridation, etc.)

Process change
During the production process, any one or more of the 5M1E (human, machine, material, method, ring, and test) production factors are changed, such as personnel changes, equipment adjustment and maintenance, refueling and replacement fixtures, and design changes. Stop the line and so on. valve grinder
First inspection requirements

The first inspection adopts three inspections: self inspection, mutual inspection and special inspection:

The submitted product must first be “self-inspected” by the operator, and then the team leader or colleague “mutual inspection”, and finally by the inspector “special inspection”, determined to be qualified before continuing to process the follow-up products.

After the first inspection, whether it is qualified or not, it shall be finally approved by a full-time inspection personnel. The inspector shall mark the first product that passes the inspection and mark it until the current class or batch of products is finished (all first-piece products must be Samples are reserved for subsequent product comparisons and see if the process has changed and marked with a marker pen to indicate passing the first test.

The first inspection is unqualified. The cause must be identified and measures must be taken. After the fault is rectified, three inspections must be carried out. It can be determined as the first one after passing the inspection. valve grinder
First item inspection main item

The figure number and the work order are in accordance with
Whether the materials, blanks or semi-finished products and work orders match
Whether the surface treatment and installation positioning of materials and blanks are consistent
Whether the formula ingredients meet the requirements
Whether the actual quality characteristics of the first product processed meet the requirements specified in the drawings or technical documents

Recommend reading and chatting with the opposite sex, it is sooner or later!
First inspection specification process

Topic content and scope of application
This document stipulates the requirements for the first inspection of new products and the inspection of the first batch of products during the production process of the company and the working procedures. valve grinder

This provision applies to the company’s first-time inspection of new products and the control of inspection of the first batch in the production process.

The production department is responsible for organizing the first inspection.

Without the new first article, first batch inspection or first inspection failure, and unauthorized production of products, the quality of the accident caused by the direct responsibility is responsible.

The inspector and the person in charge of the production line are responsible for the correctness of the first inspection. valve grinder

The confirmation work for the first piece was not completed. The inspector began to issue the quality certificate and caused the quality accident. The inspector was responsible for the responsibility.

Control requirements
The first completed semi-finished and finished products for the first continuous production in the production sector must pass the first inspection and confirmation.

For routinely produced products, the first inspection must be performed in batches.

Due to the shutdown caused by equipment, process, etc., the first inspection and confirmation must be performed when the machine is shut down and then turned on.

When the product materials and specifications are changed and put into production, the first inspection and confirmation shall be carried out.

When the first item of new product is inspected, the production unit shall be responsible for informing the inspection personnel, according to the current effective drawings, lists (or customer-supplied samples), and process documents, and the inspector shall fill in the inspection records, and after the inspection is completed, on the first card Sign and hang the card on the first product to make the first tag; the first piece of the product must be returned unqualified immediately, the first piece must be redone, and the record must be kept. Products that have not passed the first inspection may not be accepted. valve grinder

The first part as a prototype for mass production is retained by the production department until the end of the full batch production.

All raw and auxiliary materials used in the production process of the product should be inspected during the first inspection and must comply with the regulations.

Work program
During the first production process, the person in charge of the production line and the inspector should go to the production site to supervise and inspect the actual producer according to the production process, and complete the first piece according to the current effective production process document, and supervise and inspect each production process. Problems are corrected and resolved in a timely manner. valve grinder

The production of the first product of the conventional production product and the shutdown and restart production must complete all the production processes. After the manufacturer passes the inspection and signs the first piece of the product, it shall be handed over to the inspection personnel for the first inspection. During the first inspection, the inspector shall check with the responsible person of the production line according to the current effective drawings, checklists (or customer-supplied prototypes), technical documents, and product requirements, and mark the first product after passing the inspection (such as endorsement.) The first piece is qualified, etc.) and countersigned by the producer (or representative) and inspector on the first piece of card. For the first inspection of the product due to a major change may be approved by the relevant personnel and inspection signature; the first inspection is rejected immediately and the first one is re-instated. valve grinder

The first batch of new products and the semi-finished products and finished products generated after the materials and specifications are changed need to be inspected and confirmed first time.

When the first inspection is performed, the first record shall be made in time and the first confirmation shall be completed.

When quality problems are discovered in the first production, they should be promptly reflected and processed, and the non-conformities should be reconfirmed. Only when the first part of the inspection is qualified and the result is recorded on the first card and the inspector approves the quality, can production be organized.

Only after the first confirmation, the inspector can begin normal delivery inspection. valve grinder

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