In 2022
, the General Administration of Market Supervision organized the national supervision and spot check of the quality of building materials. The spot check is reported as follows:
1. Basic information
(1) Overview of spot check. 1920 batches of building materials products produced by 1704 enterprises were sampled, involving hot-rolled ribbed steel bars, cement, building waterproof rolls, aluminum alloy building profiles and other four products, and 111 batches of products were found to be unqualified (see Annex 1 for details), with an unqualified rate of 5.8%.
(2) Follow-up spot checks. There are 76 unqualified enterprises in this follow-up spot check, of which 15 enterprises are still unqualified (see Annex 2 for details) and 61 enterprises are qualified.
2. Analysis of
spot check results (1) The unqualified rate of cement spot check is 3.3%. In this spot check, 961 batches of cement produced by 961 enterprises in 28 provinces (autonomous regions and municipalities) were found to be unqualified in 32 batches, and the unqualified rate was 3.3%, which was 1.2 percentage points lower than the previous spot check. The unqualified rate of the product was 5.5%, 4.5% and 3.3% respectively in the past three years.
Fig. 1 National Supervision and Spot Inspection
of Cement Products in the Past Three Years This spot inspection focuses on 12 items of cement, such as sulfur trioxide, magnesium oxide, chloride ion, stability, strength, water-soluble chromium (VI), radioactivity, setting time, loss on ignition and water retention rate.
The unqualified items involved loss on ignition, chloride ion, water-soluble chromium (VI), stability and so on. The chloride ion items of 19 batches of products were not qualified, among which the detection value of the products produced by Weihui Tianyi Cement Co., Ltd. was 18.6 times the maximum limit of the standard. According to the analysis of technical institutions, the main reason for the unqualified chloride ion project is that in order to stimulate the early strength of cement and reduce production costs, enterprises add too many additives or admixtures with high chloride content. Eight batches of water-soluble chromium (VI) products were not qualified. According to the analysis of technical institutions, the main reasons for the unqualified water-soluble chromium (VI) project are that the production and factory inspection are not strictly carried out in accordance with the standards, or the industrial waste residue with high chromium content is used.
The above spot checks mainly involve products produced by enterprises in 8 provinces, including Anhui, Shandong, Jiangsu, Henan, Zhejiang, Hebei, Hunan and Guangdong, which are sampled and inspected in 90 batches, 77 batches, 58 batches, 55 batches, 54 batches, 53 batches, 52 batches and 51 batches respectively. The unqualified rates were 3.3%, 1.3%, 1.7%, 3.6%, 0%, 5.7%, 1.9% and 0% respectively.
(II) The unqualified rate of hot-rolled ribbed steel bars is 4.7%. 451 batches of products produced by 243 enterprises in 25 provinces (autonomous regions and municipalities) were found to be unqualified, and the unqualified rate was 4.7%, which was 3.9 percentage points lower than the previous spot check. The unqualified rate of the product in the past three years was 4.6%, 8.6% and 4.7%, respectively.
Fig. 2 National supervision and spot check
of hot-rolled ribbed steel bar products in the past three years. This spot check focuses on 21 items such as mechanical properties, process properties, chemical composition, size and shape, weight deviation, metallographic structure and surface marks of hot-rolled ribbed steel bar. After inspection, the size and shape items of 9 batches of products are not qualified, all of which are the end clearance of transverse ribs, which will affect the bonding force between steel bars and concrete. According to the analysis of the technical organization, the main reason for the unqualified transverse rib end clearance project is that some enterprises do not know enough about the measurement requirements of the project in the standard, do not carry out production and factory inspection in strict accordance with the standard, and do not update the production equipment and process in time. The chemical composition of four batches of products is unqualified, all of which are unqualified in carbon content, which will affect the toughness of steel bars and lead to brittle fracture. According to the analysis of the technical organization, the main reason for the unqualified chemical composition item is that the enterprise did not strictly check and accept the billet, and simply increased the carbon content in the smelting process to increase the strength of the steel bar, resulting in the carbon element exceeding the standard.
The above spot checks mainly involve products produced by enterprises in Guangdong, Jiangsu, Shanxi and Anhui provinces in industrial agglomeration areas. 53 batches, 53 batches, 30 batches and 29 batches of products were sampled and inspected respectively, and the unqualified rates were 3.8%, 0% and 6.9% respectively.
(3) The unqualified rate of building waterproofing membrane is 18.8%. 240 batches of products produced by 233 enterprises in 23 provinces (autonomous regions and municipalities) were found to be unqualified in 45 batches, and the unqualified rate was 18.8%, which was 2.4 percentage points higher than the previous spot check. The unqualified rate of the product in the past three years was 11.1%, 16.4% and 18.8%, respectively.
Figure 3 National supervision and spot check
of building waterproofing membrane products in the past three years. This spot check focuses on the soluble content, heat resistance, low temperature flexibility, impermeability, tensile properties, thermal aging, oil permeability, joint peel strength, peel strength, dimensional change rate of heat treatment, elongation at break, Thermal stability, nail rod tear strength and other 34 items were tested.
It was found that the unqualified items involved soluble content, low temperature flexibility, thermal aging, joint peel strength, peel strength, dimensional change rate of heat treatment and elongation at break. Among them, low-temperature flexibility and thermal aging (low-temperature flexibility) projects found more unqualified batches, with 33 batches and 39 batches of unqualified products respectively. In
this spot check, the products produced by Hebei Feiyue Petrochemical Waterproof Material Co., Ltd. were not qualified for two items of low temperature flexibility and thermal aging (low temperature flexibility). The enterprise also violated the provisions of the Product Quality Law in the national supervision spot check in 2021 and refused to accept the supervision spot check without justified reasons.
The above spot checks mainly involved the products produced by enterprises in Shandong, Hebei, Hubei and Jiangsu provinces in the industrial agglomeration areas. 73 batches, 33 batches, 20 batches and 18 batches of products were sampled and inspected respectively, and the unqualified rates were 16.4%, 27.3%, 5.0% and 5.6% respectively.
(4) The unqualified rate of aluminum alloy building profiles is 4.9%. 268 batches of products produced by 267 enterprises in 23 provinces (autonomous regions and municipalities) were sampled, covering 5 varieties of anodized profiles, electrophoretic painting profiles, powder spraying profiles, spray painting profiles and thermal insulation profiles, and 13 batches of products were found to be unqualified, with an unqualified rate of 4.9%, which was 0.3 percentage points lower than the previous spot check. The unqualified rate of the product was 5.8%, 5.2% and 4.9% respectively in the past three years.
Figure 4 National Supervision and Spot Inspection
of Aluminum Alloy Building Profile Products in the Past Three Years This spot inspection focuses on 21 items of 5 categories, including chemical composition, mechanical properties, wall thickness, film properties and composite properties of aluminum alloy building profiles.
After inspection, all the five categories of items were unqualified. Among them, 5 batches of products were unqualified in composite performance, 4 batches of products were unqualified in chemical composition, and 3 batches of products were unqualified in film performance. According to the analysis of technical institutions, the main reasons for the disqualification are that some enterprises have insufficient investment in equipment such as extruders and smelting furnaces, and that the proportion of alloys has been reduced or scrap aluminium has been added to save costs when preparing alloy components.
The above spot checks mainly involved the products produced by enterprises in Guangdong, Shandong, Jiangsu and Sichuan provinces in the industrial agglomeration areas, with 42 batches, 40 batches, 29 batches and 21 batches respectively, and the unqualified rates were 9.5%, 10.0%, 0% and 4.8% respectively.
3. Relevant requirements
In view of the problems found in the national supervision and spot check of product quality, the relevant provincial market supervision departments should do the following work well:
(1) Strengthen the handling of the results of the spot check. In accordance with the provisions of the Product Quality Law and the Interim Measures for the Administration of Product Quality Supervision and Spot Inspection, the results of supervision and spot inspection shall be handled well. For the unqualified products found by supervision and spot checks, measures such as seizure and seizure shall be taken according to law, and enterprises shall be strictly prohibited from selling them out of the factory. For unqualified enterprises, especially those with two consecutive spot checks, we should further clarify the requirements for rectification, strictly supervise the implementation of rectification measures, and organize timely review. Those suspected of committing crimes shall be promptly transferred to judicial organs. Enterprises with serious violations of law and dishonesty shall be included in the list management of enterprises with serious violations of law and dishonesty according to law. The results shall be recorded into the e-CQS system in time. The General Administration will strengthen follow-up supervision and report the results of handling according to the situation.
(2) Strengthen quality tracking and supervision. The market supervision departments of Shandong Province and Hebei Province should carry out special renovation of building waterproofing membrane products, strengthen supervision and inspection of key enterprises within their jurisdiction, comprehensively use various means to maintain the high-pressure situation of quality supervision, seriously deal with illegal acts and improve the quality and safety level.
(3) Supervise the implementation of the main responsibility. Relevant local governments and departments will be informed of the situation of unqualified products in this supervision and spot check, and effective measures will be taken to urge enterprises of unqualified products to implement the main responsibility of product quality and safety, organize production and sales in strict accordance with standards and laws, and ensure product quality and safety.
(4) Strengthen quality and technical assistance. Organize relevant industry organizations and technical institutions to help enterprises find out the reasons in depth, put forward improvement measures and solutions, and promote the improvement of industry quality level. The list of unqualified
cement enterprises is as follows:
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