1 Scope
This document specifies the consistency checks, manufacturer's internal inspections, external inspections and quality certification documents for the evaluation of the quality of reinforcement welded wire mesh. This document applies to the verification of the quality of reinforcing steel welded wire mesh products.
2 Normative references to documents
The content of the following documents constitutes an essential provision of this document through normative references in the text. Among them, note the date of the reference document, only the date of the corresponding version applies to this document; do not note the date of the reference document, its latest version (including all the change orders) applies to this document.
GB/T 1499.3 Steel for reinforced concrete, Part 3: Welded reinforcement mesh
GB/T 19001 Quality Management System, Requirements (GB/T 19001-2016,1SO 9001;2015,IDT)
GB/T 27020 Operational requirements for conformity assessment bodies of all types (GB/T 27020-2016,ISO/IEC 17020;2012,IDT)
GB/T 27065 Accumulation requirements for conformity assessment, product, process and service certification (GB/T 27065-2015,ISO/IEC 17065;2012,IDT)
3 Terminology and definitions
The following terms and definitions apply to this document.
3.1
evaluation scheme
An evaluation scheme for a specific product, to which the same requirements, rules and procedures apply.
[Source: GB/T 27065-2015, 3.9, with modifications]
3.2
Certification bodycertification body
A third-party conformity assessment body that operates a certification scheme.
Note: Certification bodies may be non-governmental or governmental (with or without regulatory powers).
[Source: GB/T 27065-2015, 3.12]
3.3
Characteristic value
The quantile value of a characteristic parameter (load, or property of a member or material) corresponding to a specified probability.
[Source: ISO 8930:2021, 3.2.2]
3.4
Welded mesh fabric type
A mesh structure consisting of a combination of reinforcement bars, which can be of different reinforcement levels and sizes.
4 Conformity check
4.1 Purpose
The purpose of the consistency check is to confirm that the production unit has the production capacity and resources to produce welded wire mesh products in accordance with the requirements of GB/T 1499.3.
4.2 Body requirements
The certification body should meet the requirements of GB/T 27065.
4.3 Process
4.3.1 General requirements
The conformity check consists of the following stages:
-Inspection of production conditions (see 4.3.2);
-Sampling inspection (see 4.3.3);
Long-term quality level inspection (see 4.3.4).
If satisfactory results are not obtained in any of the above stages, all three should be re-checked. Welded reinforcement mesh of different mesh types and different welding methods shall be checked separately for consistency. If the manufacture of a reinforcement mesh is subject to different welding processes, a full consistency check shall be carried out for the whole process.
4.3.2 Inspection of production conditions
The inspection of production conditions includes the following aspects:
-The capability of the plant's personnel and organisation;
-The capacity of the production equipment to meet the requirements;
-the independence of the quality assurance department from the production department;
-the suitability of the testing equipment required for internal testing;
-The quality management system to ensure the quality of the product, which must meet the requirements of GB/T 19001. The inspection report shall include an evaluation of the entire process from the entry of the reinforcement to the packing of the welded steel mesh.
4.3.3 Sampling and inspection
4.3.3.1 General requirements
Samples shall be taken from the production plants and sites involved and an inspection programme shall be developed to cover all grades and diameters of reinforcement in the scope of certification within one evaluation cycle.
4.3.4 Long-term quality level inspection
4.3.4.1 Scope of inspection
In order to verify the long-term quality level, the manufacturer shall increase the number of samples (internal and external tests) over a sufficiently long period of time (6 months to 1 year). During this period, the manufacturer shall carry out internal tests of double the number of tests specified in 5.2.1.1.
4.3.4.2 Evaluation
At the end of the test period specified in 4.3.3.1, the results of all internal and external tests shall be analysed independently and compared with each other. Where characteristic values are specified in the product standard, the long-term quality level shall be determined using the statistical methods in 5.2.2.2.
4.3.4.3 Approval
After the long-term quality level has been verified as satisfactory by the certification body, the certification body shall issue a certificate of conformity to the manufacturer.
5 Manufacturer's internal inspection
5.1 Purpose
The continuous internal inspection of the production plant is to ensure that the quality level is within a reasonable range over a long period of time. When the test results do not meet the requirements of the standard, take the necessary measures to improve product quality. The manufacturer's internal inspection includes: batch testing of continuous production (see 5.2.1), determination of long-term quality levels (see 5.2.2).
5.2 Processes
5.2.1 Batch inspection
5.2.1.1 Scope of measurement
A minimum of one specimen per test batch is required for each test item specified in the product standard for each welded wire mesh type for an inspection batch not exceeding 50 t.
5.2.1.2 Evaluation of test results
Where a characteristic value is specified, each test result shall satisfy the requirements of Equation (1).
5.2.2 Determination of long-term quality level 5.2.2.1 Scope of testing
All batch test results for continuous production in accordance with 5.2.1 shall be collated and statistically analysed and at least 200 test data or 3 months of continuous production test data shall be submitted to the inspection body or certification body for the purpose of determining the long-term quality level. The long-term quality level shall be assessed separately for each welded wire mesh type.
6 External inspection
6.1 Purpose
The purpose of the external inspection:
--Continuous testing of the continuous fulfilment of production conditions and continuous testing of the product in an environment that meets the production conditions test (see 4.3.1)
-To provide continuous monitoring of the internal inspection procedures in chapter 5.
6.2 Bodies
The certification body may authorise an inspection body to carry out external inspection and supervision, which shall comply with the requirements in GB/T 27020.
6.3 Process
6.3.1 The inspection body shall carry out external testing and monitoring at intervals of up to 12 months.
All indicators for which internal tests are carried out shall be tested. Samples shall be taken from the manufacturer's or user's stock. Test results shall be statistically analysed and compared with the results of internal tests.
During the sampling, testing and evaluation process, the systematic errors of the internal and external test results should also be evaluated. Finally, at least 10 specimens of the same mesh type shall be tested in parallel by the manufacturer and external inspectors and the results shall be compared.
6.3.2 A long-term quality level test shall be carried out at least once a year and compared with the internal test results, see 5.2.2.
6.4 Evaluation
The results of the external inspection shall be recorded in the inspection report, which shall be submitted to the certification body. If the results show non-conformity, the appropriate measures shall be taken depending on the type and significance of the defects recorded, e.g.:
-A warning to the manufacturer
-increase the testing efforts
-Requiring a change of production conditions
-withdrawal of certification.
7 Quality documentation
7.1 Welded wire mesh products manufactured in accordance with the requirements of the relevant product standards and quality assured in accordance with Chapters 5 and 6 shall be provided with documentation including the following:
a) the name of the plant
b) trademark;
c) External inspection body;
d) Nominal diameter;
e) Name of the standard to be applied;
f) Quantity;
g) Date of manufacture;
h) consignee.
7.2 If the product is supplied through a distributor or processor, the distributor or processor shall confirm on the quality certification document that the inspection of the product was carried out in accordance with this document.
Appendix A (informative) Technical differences between this document and ISO 11082:1992 and their causes
Bibliography
contents
1 Scope
2 Normative references to documents
3 Terminology and definitions
4 Conformity check
5 Manufacturer's internal inspection
6 External inspection
7 Quality documentation
Appendix A (informative) Technical differences between this document and ISO 11082:1992 and their causes
Bibliography
