In the design and production process of any product, there are often design changes, process changes, process adjustments, unplanned line stops, production changes, and line changes. So, how to ensure that these activities will not affect the subsequent production quality? This requires first-article inspection in the operation preparation verification and post-production verification stages.
Definition of first-article and first-article inspection
Process change
During the production process, any one or more production factors in 5M1E (people, machines, materials, methods, environment, and measurement) change, such as personnel changes, equipment adjustments and repairs, material and fixture changes, design changes, line stops, etc.
First piece
At the beginning of each shift/production line production or after the process changes, the first or first few products processed by the production line. For mass production, "first piece" often refers to a certain number of samples.
First piece inspection
Inspection of the first or first few products processed by the production line at the beginning of each shift or after the process changes. The number of inspections can be determined according to the requirements of different companies or customers.
Generally speaking, at least 3 to 5 products produced continuously need to be inspected, and only after they are qualified can the subsequent products be processed. Before any changes in equipment or manufacturing processes, and before each work shift begins processing, the first piece inspection must be strictly carried out.
Purpose of first piece inspection
The first piece inspection in the production process is mainly to prevent batch out-of-tolerance, rework, and scrapping of products. It is a means of pre-controlling the product production process, an important method of product process quality control, and an effective and indispensable method for enterprises to ensure product quality and improve economic benefits.
The first piece inspection is to find out the factors that affect product quality in the production process as early as possible and prevent batch defects or scrapping.
Formal production can only be started after the first piece inspection is qualified, mainly to prevent the occurrence of batch defective products.
Long-term practical experience has proved that the first inspection system is an effective measure to find problems as early as possible and prevent batch scrapping of products.
Through the first piece inspection, it can be found that there are systemic reasons such as severe wear of fixtures or installation positioning errors, poor accuracy of measuring instruments, reading wrong drawings, feeding or formula errors, so as to take corrective or improvement measures to prevent batch defective products.
Timing/Occasions for First Article Inspection
1. At the beginning of each work shift. 2. Changing operators. 3. Changing or adjusting equipment and process equipment (including tool replacement or sharpening). 4. Changing technical conditions, process methods and process parameters (such as changes in roughness requirements, changing inner hole reaming to boring, changes in tool feed or speed in CNC programs, etc.). 5. After adopting new materials or material substitutions (such as material changes during processing, etc.). 6. Changing or retesting tank liquids, etc. (such as phosphating, nitriding, etc.).
Requirements for First Article Inspection
The first article inspection adopts a three-inspection system: self-inspection, mutual inspection and special inspection.
The products submitted for inspection must first be "self-inspected" by the operator, then "mutually inspected" by the team leader or colleagues, and finally "specially inspected" by the inspector. Only after they are determined to be qualified can the subsequent products be processed.
Whether the first piece is qualified after the first piece inspection should be finally recognized by the full-time inspector. The inspector should mark the qualified first piece with the specified mark and keep it until the processing of this class or a batch of products is completed (all first pieces must be kept for comparison with subsequent products to see if the process has changed, and marked with a marker "√" to indicate that the first piece inspection has been passed).
If the first piece inspection fails, the cause must be found out and measures must be taken. After troubleshooting, the product must be reprocessed and inspected three times until it is qualified before it can be determined as the first piece.
Main items of first piece inspection
1. Whether the drawing number is consistent with the work order. 2. Whether the materials, blanks or semi-finished products are consistent with the work order. 3. Whether the surface treatment and installation positioning of the materials and blanks are consistent. 4. Whether the formula ingredients meet the specified requirements. 5. Whether the actual quality characteristics of the product after processing meet the requirements specified in the drawings or technical documents.
Standard process for first piece inspection
Subject content and scope of application
This document stipulates the requirements and work procedures for the first piece inspection and batch first piece inspection of new products during the production process of the company. This regulation applies to the company's control of the first piece inspection and the first piece inspection of new products during the production process. Responsibilities
The production department is responsible for organizing and arranging the first piece inspection. If a product is produced without the first piece inspection of the new product or the first piece inspection of the batch or if the first piece inspection fails, the person directly responsible shall be responsible for the quality accident caused by it. The inspector and the person in charge of the production line shall be responsible for the correctness of the first piece inspection. If the inspector begins to issue the quality certificate before the first piece confirmation work is completed, the inspector shall be responsible for the quality accident caused. Control requirements
The first completed semi-finished product and finished product of the first continuous production of the production department must be inspected and confirmed by the first piece. For conventional production products, the first piece inspection shall be carried out by batch. If the shutdown caused by equipment, process and other reasons, the first piece inspection and confirmation shall be carried out when the machine is restarted after the shutdown. The first piece inspection and confirmation shall be carried out when the product material and specifications are changed and put into production. During the first piece inspection of new products, the production unit shall be responsible for notifying the relevant inspection personnel, and the inspection shall be carried out according to the currently valid drawings, lists (or samples provided by customers), and process documents. The inspector shall fill in the inspection record, sign on the first piece card after the inspection is qualified, and hang the card on the first piece product to mark it as the first piece; if the first piece inspection fails, it shall be returned immediately, the first piece shall be redone, and records shall be kept. Products that have not passed the first piece inspection shall not be accepted. The first piece is a sample of mass production, and the production department shall be responsible for retaining it until the whole batch production is completed before it can be finally delivered. During the first piece inspection, all raw and auxiliary materials used in the product production process shall be checked and must comply with the regulations. Working procedures
During the first piece production process, the person in charge of the production line and the inspection personnel shall go to the production site to supervise and inspect the actual producer to complete the first piece according to the production process and the currently valid production process documents, and supervise and inspect each production process, and correct and solve problems in a timely manner.
The first piece production of conventional production products and products that have been shut down and restarted must complete all production processes, and after the producer has passed the inspection and signed on the first piece card, it will be handed over to the inspection personnel for the first piece inspection. During the first piece inspection, the inspector shall, together with the person in charge of the production line, conduct inspections according to the current valid drawings, lists (or samples provided by customers), process documents, and product requirements. After passing the inspection, the first piece of product shall be marked (such as signing "first piece qualified", etc.), and the producer (or representative) and the inspector shall sign on the first piece card. For the first piece inspection required due to major changes in the product, the relevant personnel and the inspection signatures can be approved; if the first piece inspection fails, it shall be returned immediately and the first piece shall be redone.
The first batch production 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 for the first piece.
During the first piece inspection, the first piece record should be made in time and the first piece confirmation letter should be filled in.
When quality problems are found in the first piece production, they should be reported and handled in time, and the unqualified items should be reconfirmed. Only when the first piece is inspected and the results are recorded on the first piece card, and the inspector approves the quality, can production be organized.
Only after the first piece is confirmed, the inspector can start the normal delivery inspection work.
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☞Source: Benchmark Lean ☞Editor: Xu Peipei ☞Proofreader: Shao Yujie ☞Reviewer: Wu Xiaolan ☞Media Cooperation: 010-88379790-801 Statement: If the videos, pictures, and texts used in this article involve copyright issues, please inform us as soon as possible. We will confirm the copyright based on the proof materials you provide and pay royalties according to national standards or delete the content immediately!
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