State of the standard and quality of electric welding machine manufacturing

With the continuous increase in the market demand for electric welding machines in China, foreign welding machine products have entered the Chinese market in large numbers, and some have even established production enterprises in China. Welding machine products produced by Chinese enterprises have also gradually entered foreign markets with China’s The market demand for electric welding machines continues to increase. Welding machine products from abroad have entered the Chinese market in large numbers, and some have even established production enterprises in China. Welding machine products produced by Chinese companies have gradually entered foreign markets, even developed regions in Europe and America, making China The welding machine's processing, manufacturing, standard setting and testing are gradually in line with international standards. We will report and communicate directly to leaders and entrepreneurs on the direct association standards, CCC certification, and certification supervision, sampling inspection and analysis of the Welding Weaver's Quality Work Department.

First, the development of welding machine standards China's welding machine standard research, verification and formulation has always been a large gap between the international standards organization IEC and ISO and developed regions and national standards, in recent years, especially after the accession to the WTO, the Chinese government is very Regarding standard work, the National Standards Committee has formulated a series of work plans with many quantified objectives, such as the number of newly established Technical Committees (TCs), how many national standards have been established, how many international standards have been drafted, and international standards. Adoption rates, etc., have also increased investment in the research, verification, and formulation of standard standards. The welding machine's standard work also used this as an opportunity, and got a relatively rapid development.

1. The number of standards that have been revised and revised has increased significantly. In order to meet international standards and meet the needs of trade and technical barriers, the number of standard revisions from 2007 to 2009 exceeded 20.

2. The standard involves a wide range of standards, the first set of standards will appear, and there are also international standards that can be referenced and independently drafted. In addition to the conventional standards for arc welding, resistance welding and auxiliary equipment, new aspects such as energy efficiency, electromagnetic compatibility (EMC), damage evaluation and metering of human body with low-frequency magnetic fields will be involved.

3. The national funding for standard research has achieved historical breakthroughs. The National Finance's channel for the funding of projects has set up a special application channel for public welfare projects in standards, which facilitates the counterparty declaration of standard projects. The Standardization Committee for Electric Welders (TC70) received financial support from the State Finance Bureau in 2007. It is mainly used for the study of damage assessment of human body by low-frequency magnetic fields, and also applied for the 2008 project “Energy Efficiency Study of Electric Arc Welding Machines”.

4. Unprecedented attention to standards by the society, and the division of labor is more detailed. In accordance with the requirements of the National Standardization Committee, consistent with the division of labor between IEC and ISO, the TC70 Secretariat proposed the concept of division of labor (ie: IEC/TC26/WG5 EMC Working Group, IEC/TC26/WG1 Arc Welding Working Group, IEC/TC26/JWG2 Terms The working group and the ISO/TC44/SC6/WG2 solder mask working group), and the members of the meeting were approved by the meeting of the members in 2007. In May 2008, the National Standards Commission publicly solicited the group leader unit of the working group on the website, and the non-welding machine industry organization has filed an application as the group leader unit. After being coordinated by many parties, there was no case where the non-welding machine industry organization was the leader of the working group.

Second, changes in the welding machine CCC certification Welding machine products belong to the original needs of the Great Wall Certification (CCEE) products, but also in 2001 the national implementation of CCC certification of the first batch of compulsory certification products, was the first edition of "electrical and electronic products The "Rules for Conducting Class Compulsory Certification" (CNCA ¬ 01C-015:2001) is the implementation rule for certification. After several years of CCC certification activities and conclusions, it was discovered that the first implementation rule was partly inappropriate. Under the leadership of the SCAR, the Technical Experts Group of the CNCA revised the implementation rules in 2007. A new version of the implementation rule "Regulations for the implementation of compulsory certification for electrical and electronic products - Electric Welder" (CNCA ¬ 01C-015:2007) was issued. The requirements of the 2007 CCC implementation rules and the 2001 version of the implementation rules for CCC certification activities are somewhat different. The main differences are now described below.

1, the scope of application: 2001 version of the scope of application is based on a variety of product descriptions, similar to a variety of functions of the product inconvenient. The 2007 edition uses the internationally-defined definitions and product name examples simultaneously to facilitate understanding and product correspondence.

2. The conformance requirements for certified products are more specific and more operational: At least one sample is to be taken for consistency check of each certified product. The contents of the inspection include witness testing and verification of the following:

1. The product name, specification and model indicated on the nameplate and packing box should be the same as those indicated on the type test test report;

2. The structure of the certified product should be consistent with that of the type test.

3. The key components, important components and raw materials shall be the same as those declared in the type test and confirmed by the certification body;

4. Attestation pilot project at least as an example inspection project.

3. The winding of the key components (materials) has been added: The 2007 version of the implementation rule controls the winding wire as a key component (material) and requires separate sample delivery for testing. If a CQC voluntary certification is obtained, it can be exempted from Testing, but samples or related information should still be provided for verification by the certification body.

4. Sampling inspection after the increase of post-certification supervision: The requirements of the 2001 version of the implementation rules for post-certification supervision and sample inspection are “If necessary, samples can be taken and sent to the testing organization for testing”, before the implementation of the CCC certification of the welding machine until the implementation of the 2007 version of the implementation rules No supervised sampling tests were conducted. The 2007 implementation rules stipulate that the certification body shall be responsible for the formulation of the supervision sampling test plan and shall be responsible for its implementation (except for resistance welding machines, which shall be carried out only when necessary). Up to 1 representative sample per pump unit

III. Introduction of the sampling status and results analysis of certification supervision Since the beginning of 2008 to the end of June, 300 samples have been sampled by the Chengdu Electric Inspection Institute, and the pass rate is only 81%. This year's sample inspection project mainly involves insulation resistance, dielectric strength, temperature rise, abnormal operation and identification, and the most important non-conformities include: temperature rise, thermal protection, protection and grounding, and identification. A brief analysis of the items with a high probability of disqualification is as follows.

1. Unsatisfactory temperature rise: There are several factors that contribute to the failure of this project:

1. The manufacturer has not noticed any change in the material of the winding (or magnetically conductive material) provided by the supplier;

2. CCC certification is divided into units, and the sampled products are the same unit as the type test samples, but the specifications are different, and the specifications of the products themselves have unqualified factors;

3. There may be a manufacturer who has changed the main material or material;

4, due to time, technology or other reasons, may be individual certified companies to send samples of the initial certification products are not their own manufacturing, through the purchase of replacement nameplates and other methods to complete the sample.

2. Failed thermal protection: This failed project manifests itself in two aspects: on the one hand, the color of the thermal protection indicator and the indication of protection action and recovery do not meet the standard requirements; the second is the heat for thermal protection. The error of the operating temperature of the sensitive element is too large. The error of the operating temperature of the general temperature-controlled relay is ±5°C to ±8°C. After installation, it is also related to the degree of close fitting between the installed position and the temperature sensing surface. Two factors are the main factors causing the failure of thermal protection devices.

3. Protection failure: The main reason for the failure of this project is that the manufacturer's rectification of the commitment after the certification was not in place or there was no rectification at all. In the initial stage of CCC certification, in order to shorten the time for obtaining certification, the company's sample delivery products may have unfavorable items such as enclosure protection, nameplates, and logos. The certification testing organization may receive the improved drawings of the sample delivery company and promise to rectify it according to the drawings. Release.

4. Protective earthing and identification: This unqualified item is mainly manifested in three aspects. On the one hand, the shell grounding screw is not used for independent purposes, and it is also used for fastening purposes; the second is the color of the internal protective earthing wire or The color of the cable used in the protective grounding cable is not in accordance with the provisions of the use of green and yellow color line, or the internal grounding screw is not a separate use; the third aspect is the protective grounding mark does not use the standard regulations. The main reason for this disqualification should be that the manufacturer's rectification of the promise after the certification was not in place or there was no rectification at all.

In addition, there are some problems in terms of sexuality: If the company name, address, technical parameters of the product and even some models and certificates exist inconsistencies. Although there is no requirement to make a non-conformity judgment during the sampling inspection, the certification certificate shall be suspended in strict accordance with the requirements of the implementation rules.

Through the analysis of the four projects with high probability of non-conformities, the projects that will truly cause changes in the material cost of products that may actually undergo rectification or improvement due to unqualified products may have only temperature-rising items that are protected against heat, protection, and grounding. There are no major changes in the cost of product materials to identify qualified and unqualified items, but there is still a relatively high rate of nonconformity. This is only a matter of thinking.