About ISO 3834
Quality Requirement for “Fusion Welding of Metallic Materials”
Many companies have achieved certification to ISO 9001 with respect to their quality management systems. But where significant use is made of a special process like welding, such certification is unlikely to provide the required demonstration of company capability to manufacture products with the required product quality. In such cases compliance to ISO 3834 is the recommended solution.
For long a majority of people have thought that a defined level of quality for any product or service may be achieved through implementation of a ‘manual and several documented procedures’ as is required in ISO 9001. They do not give due importance to specific technical knowledge over the fabrication process.
This approach gives rise to ‘virtual quality’ where the relationship between the ‘critical quality’ and ‘actual quality’ of the product or service is a matter of accident. To achieve ‘real quality’ it is necessary to give top priority to the ‘specific technical competence’ of the fabrication process.
The international trend in quality management seems to have recognised this aspect and is moving from systems to process/product approach . Consequently, the responsibility of the product conformity to the regulatory and contractual requirements is primarily on the Manufacturer .
Given that the Manufacturer is fully responsible for his product conformity, a competent effective control of the whole fabrication course is the most important aspect – being both the correct way to face the responsibility and the best route to fulfil the contractual and regulatory requirements without any waste or extra costs. This is particularly true when a ‘special process’ like welding, with its ancillary activities (e.g. PWHT, NDT etc.) is involved.
ISO 3834 certification can be achieved in 3 levels of quality requirements:
ISO 3834-2: Comprehensive quality requirements
ISO 3834-3: Standard quality requirements
ISO 3834-4: Elementary quality requirements
The manufacturer should select one of these three parts specifying different levels of quality requirements, based on certain criteria related to products e.g. the extent and significance of safety-critical products, the range of products manufactured, the complexity of manufacture, the range of different materials and welding processes used, the extent to which metallurgical problems may occur, the extent to which manufacturing imperfections, e.g. misalignment, distortion or weld imperfection, affect product performance, etc.
A manufacturer that demonstrates compliance to a particular quality level is considered to have established compliance to all lower levels without further demonstration [e.g. a manufacturer compliant to comprehensive quality requirements (i.e. ISO 3834-2) demonstrates compliance with standard quality requirements (i.e. ISO 3834-3) and elementary quality requirements (i.e. ISO 3834-4)].
The most crucial point in implementing a fabrication control according to ISO 3834 deals with the criteria through which the Manufacturer can select the appropriate part of the reference standard. This choice is heavily conditioned to the development of all the process control. Such criteria can be summerised as below:
• The criticality of the product from safety point of view;
• The manufacturing complexity of the product;
• The materials involved;
• The possible metallurgical problems that can arise;
• The welding processes and the level of automation;
• The significance, with respect to the expected service, of the possible manufacturing defects.
Thus, the correct part of the ISO 3834 to be chosen is not necessarily on the demanded quality, but rather on the real need for the specific fabrication process to be kept under control, in order to guarantee the expected level of quality.
ISO 3834, with regard to the management control of the fabrication process, focuses on
- Review of technical and contractual requirements
- Welding personnel
- Calibration and validation
- Identification and traceability
For all of them, additional information has been worked out, to guide Manufacturers in applying a profitable management control.
To take into consideration the specificity of different product certification where for different welded products, ISO 3834 compliance has now been made mandatory. The following table gives some examples:
Being convinced that without an appropriate specific technical competence (combination of knowledge and experience) no management system can be successful in manufacturing any product, a great importance has been given to the ‘Welding Coordinator’, who becomes the key element around whom all the welding production process works. The evaluation of the Welding Coordinator’s competence, on the applied fabrication process and the relevant products, is explicitly required (through a technical interview or examination of a proper supporting documentation) to the Assessors during the certification process.
Even from Risk Management point of view, the IIW approach appears to be convenient: in fact, the potential risks are likely to turn to damage if the process management applied shows ‘vulnerabilities’ in some specific area. And in any fabrication process, welded products included, the first vulnerability is the lack of a competent fabrication control.
A recent European survey carried out amongst the Manufacturers who have already implemented ISO 3834 has revealed that 85% of the respondents have found the scheme to have many managerial advantages in keeping the fabrication process under control and also have found this to enhance quality and money saving. In the same survey 45% of the respondents have been able to quantify savings in their fabrication cost.