Presented at the British Institute of NDT International Conference 'Certification 99' held in Meriden, nr Coventry, UK, 28/29 April 1999.
Welding has long been considered a particular technology with its own requirements and standards. It is widely regarded as a 'Special Process' as defined in the ISO 9000/EN 29000 series. This led to the introduction of ISO 3834/EN 729 which lay down quality requirements for welded fabrication. Within these Standards are the expectations of qualification and experience of key personnel involved in assuring the quality of welded construction.
A Welding Co-ordinator is defined and the role and responsibilities are given in EN 719, the informative Annex A of which suggests that a Diploma from the European Welding Federation (EWF) is an appropriate knowledge qualification for this function. ISO 3834/EN 729 also state that NDT personnel should be qualified to a scheme which complies with ISO 9712/EN473. These Standards are detailed on the requirements of examination structure and certification but do not cover all NDT techniques. In particular Visual Inspection is only covered by the sentence:
'The system described in this Standard may also apply to Visual Inspection, .......... where National Certification programmes exist'.
Inspection of welds is a particular form of Visual Inspection which requires knowledge of the welding processes, the potential and reasons for defect formation and methods of rectification. Certification for Welding Inspection has therefore been somewhat separate from other NDT techniques and has been developed by the organisations with prime responsibility for welding rather than the NDT organisations.
This paper seeks to review the status of Welding Inspection Certification, the personnel seeking qualification and the evolution and interaction of schemes around the world.
Certification versus Qualification
It is perhaps necessary to highlight the difference between Certification and Qualification. In the English language the word 'certificate' is used rather liberally. It can mean a piece of paper stating that a person was at a certain place at a certain moment in time, this having no value in showing that person's experience gained. For example people are given 'certificates' for attending some manufacturers' product launches.
'Certification' however has a more positive meaning; that the person has been assessed in some manner and found to meet specific criteria by an Authorised Body. These organisations also issue pieces of paper, 'certificates', to show this achievement. As there is no distinction in the language it is important to recognise the title bestowed on the person undergoing this process. Thus EWF has chosen to use the phrase 'Certified European Welding Engineer' etc. and AWS calls its people Certified Welding Inspectors. CSWIP has not added such words but relies on the fact that a 'Welding Inspector' is a job function which clearly needs assessment to establish competence.
As the EWF expanded its system it became apparent that use of the word 'certificate' would cause confusion if applied to the record of achievement in a straightforward education programme. The alternative word 'diploma' is therefore always used to signify that the person has achieved a level of education that cannot be taken from them. Certificates are subject to review and periodic renewal and, if the applicant can no longer show competence or a relevant job function, they may be cancelled.
The difference may be summarised as that difference between education and experience.
In 1976, both the American Welding Society (AWS) and The Welding Institute (TWI) through their Certification Body, the Certification Scheme for Welding and Inspection Personnel (CSWIP), began qualification of welding inspectors. Since that time some 50,000 persons have gained Certificates. In other countries such as Canada and South Africa similar schemes were introduced but for the most part the AWS and CSWIP schemes have been adopted internationally. With more than 30 years history behind them the AWS and CSWIP schemes tend to dominate and many international companies, e.g. oil companies specify that Inspection personnel shall have certificates from one or other of these schemes.
Whilst other national schemes are well recognised in their national boundaries, they have sought recognition with these two dominant schemes to gain acceptance in a wider market. The Canadian Standards Association system is very similar to the AWS one, having three levels recognised by AWS as giving equivalent qualification to their own. They have in fact developed 'reciprocity' under which a certificate holder in the one scheme may apply for a Certificate from the other without further examination. The South African Association of Welding (SAIW) has reached an agreement with CSWIP for large areas of exemption from testing for persons holding the comprehensive SAIW qualification who are seeking CSWIP certification. AWS and CSWIP have made arrangements for 'bridging' examinations between their level 2 Welding Inspectors. The syllabuses of the two schemes are noticeably different but there is sufficient overlap to make the bridging a relatively short test of specific aspects.
This mutual recognition has reduced potential competition and it is to be expected that it will eventually produce harmonisation and possibly integration of the main schemes.
Such developments have considerable benefits for the operators. It is not uncommon for different companies, even within the same country, to call for different Inspection Certification Schemes. This requires the operators to hold qualification to both if they are to work for more than one company. The recognition system helps greatly in avoiding costly duplication of effort both on the part of the individual and his employer who has fewer certificates to monitor for validity.
These schemes were taken as the basis of comparison by the International Institute of Welding (IIW) when it set up a Working Group within Commission XIV targeted to produce an International Welding Inspector qualification. The IIW is a body of some 40 organisations each representing the welding society of their particular nation. It has in the past been given responsibility for formulating Standards on welding which form the basis of ISO Standards. Whilst this role is under review, it remains the means of achieving agreement throughout the world on matters of importance to welding. The work on Welding Inspectors is still in the formative stage as the Working Group is considering whether the need is for qualification after education, i.e. a 'diploma' valid for life, or certification which demonstrates competence at a particular point in time and is subject to renewal at intervals.
The EWF has 27 organisations from countries within, and associated with, Europe. These members are also members of IIW and EWF has given the full syllabus together with the system for access to training and examination on Welding Engineer, Technologist, Specialist and Practitioner to IIW so that they work from an identical base. These are the qualifications referred to in the Annex of EN719/ISO 3834.
EWF has also considered the function of welding inspection and has published Guidelines for the education of Welding Inspection Personnel at four levels. It is highly probable that these will form the basis of the IIW scheme when it is finalised. They may yet be totally accepted as they exist in a manner similar to that for the Welding Engineer, etc.
The normal approach of EWF is to offer a training course that can take people with appropriate prior level of education but without experience through the knowledge acquisition necessary to gain a welding qualification. The successful candidate is awarded a diploma that signifies achievement forever in the same way as school or university examinations. This does not however constitute an assessment of ability to carry out any particular job function.
More recently EWF has seen the need for Certification of personnel to demonstrate their current competence. This has resulted in a scheme for Welding Engineers and other levels being able to be assessed on their ability to perform an actual job function. They must therefore be employed in a welding engineering role and must be assessed by peer review at regular intervals. For this they receive the title 'Certified European Welding Engineer' (Cert EWE), etc ( Figure 1). This concept is now being discussed in EWF for inspection personnel. Operators who have received diplomas from EWF as European Welding Inspection Practitioner, Specialist, Technologist or Engineer may be assessed for job competence and be awarded Cert EWI-P, etc.
|Figure 1. Steps to Certification for a Welding Engineer|
||Technical knowledge requirement
'European Welding Engineer'
||Two years recent experience
Relevant job content and level
||Demonstration of maintaining
And developing technical knowledge
||Assessment by Authorised National Body
||Issue of Certificate (renewable every 3 y)
'Certified European Welding Engineer'
Whilst such a scheme is ideal for progressing inexperienced personnel through full education in welding and inspection and into work experience, it is somewhat restricting for those who have learnt the skills over years of operating in an appropriate job function. There is therefore an argument that it is complementary to the AWS and CSWIP approach rather than replacing them. It is however most likely that a qualification will evolve which will incorporate the best aspects of the thinking of all of the schemes of IIW, EWF, AWS and CSWIP. CSWIP is already recognised as giving equivalent qualification to EWF; a CSWIP Welding Inspector may receive a diploma of European Welding Inspection - Practitioner and a Senior Welding Inspector may receive an EWI - Specialist without further examination. It is therefore to be expected that when Certification becomes part of the EWF scheme that equivalence with the CSWIP scheme will also be sought with this.
The Job Function of Welding Inspector
The fabrication industry has built its reputation upon the skill of the workforce, at all levels and in all job functions, and the quality control that it applies to the article during and after manufacture. Traditionally a system of 'checkers' is used where one person verifies the work of another. This is most usually in the form of Quality Control Inspectors who check components against specification tolerances.
Welding has particular aspects to be checked and so a role of Welding Inspector developed early in the 20 th Century as fabrication became more a product of a team rather than a single artisan. This role gained full recognition with the introduction of the AWS and CSWIP schemes noted above and for many years welders were expected to work to procedures which were overseen by Welding Inspectors producing results which required acceptance by Welding Inspectors. The responsibilities of welding inspection were noted to cover actions before, during and after welding, differing considerably from a straightforward quality check or indeed normal NDT inspection. This required considerable welding and fabrication knowledge on the part of the Welding Inspector. Hence the very separate and intensive training programmes and the distinction from other forms of NDT.
This requirement for knowledge of the process, its control and means of optimisation has led to certain companies recognising that other members of their workforce could operate as inspectors. Welding Supervisors obviously also need to know all of these aspects in order to be able to advise their welders on the selection of parameters and correction of faults. In any workshop operating to quality principles the supervisor must also take responsibility for the fitness for purpose of the output. In other words he/she must know the acceptance criteria, a key function of welding inspection. Thus it is that many personnel in supervisory positions take CSWIP type qualification in inspection and carry out the function eliminating the need for a separate role.
The Welder as an Inspector
Once a company recognises that welding is a special process and introduces an EN 729 type of quality assurance, it becomes clear that the welder is a vital operator in the achievement of output. EN 729 requires that welders are appropriately qualified, usually to ISO 9606/EN 287. For a welder to achieve such qualification and to produce welds consistently in production he/she must understand the control of parameters and the acceptance criteria against which the job is judged. That is, a 'quality' welder is as aware of the requirements before, during and after welding as is a supervisor or an inspector.
It has been traditional that the best welders, those with a good understanding of the needs of fabrication and a positive attitude to quality, gain promotion to inspectors, supervisors and workshop managers. This being so it is only logical to seek to give good welders greater responsibility during their career 'on the tools'. Welders do not try to produce bad work. If they have an appreciation of what is required they will attempt to achieve it. So it is that some of the more advanced thinking companies are training welders in inspection and acceptance criteria so that they can be the first line of quality assessment. It is far better to have a welder who knows what is sought and is striving hard to produce all his/her work to that standard that to try to 'inspect out' inferior work after completion. 'Right first time' is always the most cost-effective way to best quality.
The payback from such an approach is highly significant. BARMAC are constructors of offshore oil platforms. Working under the traditional system of inspection they had production figures of 99 man-hours per tonne with a repair rate of 0.41%. These were considered very good at the time but when they introduced the principle of 'self-monitoring' by welders, not only did the man-hours per tonne fall to 78 but the repair rate also fell by 60%.
Such an approach requires that welders be trained in inspection, understanding the welding process and working to QA requirements. This may require an investment in training but it is one that pays off very rapidly. The cost of inspecting, removing and repairing unacceptable welds has been estimated to be around five times the cost of the original work.
Some observers express concern about allowing welders to carry out 'self inspection'. If, however, such a function is part of the team approach to getting things right first time and all work is the ultimate responsibility of the supervision backed by a full QA system, use of the welders eyes and brain has to be beneficial. Dangers exist only if there is no control on the welder and the remuneration package is such as to tempt him/her to pass off inferior work as acceptable. BARMAC engineers point out that welding is possibly the only trade which requires an operator to prove his/her ability regularly throughout life. With such skill and conscientiousness it is not surprising that 'quality welders' can make a real difference to production efficiency.
Qualification of Welders in an EN 729 System
Following the logic above, there is a need to offer training and assessment for quality welders. CSWIP recognised this and reviewed the least senior of its certification levels to accommodate the need. The lowest level had been Assistant Welding Inspector but there appeared to be very little call for such a position as Welding Inspectors do not operate with assistants. The CSWIP Management Committee therefore revised the criteria and renamed this first level 'Visual Welding Inspector'. This gives a recognisable title to certification that can be used by companies to give status to their 'quality' welders.
Due to the demise of the apprenticeship schemes, the understanding required of such welders may be lacking. They may have picked up by a combination of education and experience the rudimentary principles but this may be far from comprehensive. ISO 9606/EN 287 have recommended knowledge modules in an Appendix but it is not compulsory and little used in the UK. EWF has issued Guidelines for European MMA, MIG/MAG, etc. Welder but these require a considerable number of hours of study. In the UK, National Vocational Qualifications (NVQ) have been introduced to try to give qualification to workplace based learning but these do not necessarily give an assurance of knowledge of fundamental principles.
There is a recognition that the requirement to train welder more broadly is not adequately covered by existing specifications and guidelines so a Working Group of IIW and EWF is attempting to define a syllabus. This must meet both the need of a raw student and the part educated industrial welder. Until completion of this task, companies and associations are likely to continue to specify their own requirements or to use organisations such as TWI which offers a series of modules covering workshop practice, QA principles, etc. leading to the award of a Quality Welder qualification.
The Way Forward
The principle of having someone to watch over the work of another is deeply embedded in manufacturing and fabrication. It is possibly based on the use of unskilled and semi-skilled workers who could not be expected to make value judgements on what they are doing. However, welding is recognised in the Standards as being a 'Special Process' and so the skills required to execute it and inspect it are seen as particular. The skill required of the welder is such that he/she must have a good understanding of principles and requirements of fabrication. It is therefore sensible to utilise this understanding to from the first line of inspection. Supervisors and Quality Engineers can then take on a monitoring role, sampling the work of Quality Welders rather than positively releasing every step. Whilst this is carrying out the full function of a Welding Inspector, it is not a separately defined role. However, the need for appropriate training and qualification remains. There may be fewer people with the title 'Welding Inspector' but more personnel competent to carry out the function.
With so many industries becoming 'global', it is seen as essential that such qualification is carefully controlled and harmonised across the world. The way forward is through agreements such as that between AWS and CSWIP and through unified systems such as that proposed by IIW.