African Fusion June 2018

AFRICAN JUNE 2018

Journal of the Southern African Institute of Welding

Prime ARCAL™

Chrome ARCAL™

Speed ARCAL™

Force ARCAL™

Contents

June 2018

FEATURES 4 70 years on: the SAIW president looks back In the year of its 70 th anniversary, current SAIW president, Morris Maroga, takes a look at how far the Institute has progressed since 1948. 10 NDT challenges relating to new materials, health and life extension projects Presenting at the NDT Conference hosted by SAINT earlier this year, Tony Paterson highlights the need for adopting new approaches to NDT in response to new materials and new operational imperatives. 14 Laser-MIG hybrid welding of thick-section titanium TC4 alloy: This paper presents research from the Harbin Institute of Technology (HIT) on the welding of thick section TC4 titanium alloy materials using Laser-MIG hybrid welding. 20 Aeroswift: a large-scale powder bed fusion AM system Hardus Greyling of the CSIR and Marius Vermeulen from Aerosud Innovation and Training talk about Aeroswift, an R&Dproject involving the development of one of the largest laser-based additive manufacturing (AM) machines in the world. 24 Welding to meet sanitary standards African Fusion talks to Air Products’ Sean Young, about the fabrication of surfaces and piping for hygienic handling of food and beverage products. 26 Mechanised and automated TIG welding Polysoude presents its innovative, customer-focused solutions with its mechanised and automated TIG welding technology. 28 Quality advantages from double-coated electrodes Alain Laurent, business developer for Lincoln Electric’s Oerlikon brand, highlights the advantages of Tenacito double-coated SMAW electrodes. 29 NAMPO: an annual welding bonanza for farmers African Fusion visits Afrox’s NAMPO stand in Bothaville and talks to Johan Pieterse and Brett Cameron about welding solutions for the farming community. 31 Metal spray solution for hydro pump turbine A coating solution fromSurcotec extends the Labyrinth seal casing life span and saves costs for Eskom’s Palmiet Hydro installation. REGULARS 3 Sean’s comment 6 SAIW bulletin board 8 Front cover story: Connected store for onsite supply of gases and hardgoods 32 Welding and cutting forum 40 Today’s technology: Practical, powerful and quiet new TIG series

Published four times a year and mailed out together with MechChem Africa by: Crown Publications cc Crown House Cnr Theunis and Sovereign Streets Bedford Gardens 2007 PO Box 140

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Bedfordview 2008 Tel: (011) 622 4770 Fax: (011) 615 6108

Editor: Peter Middleton E-mail: peterm@crown.co.za Advertising: Helen Couvaras E-mail: helencou@crown.co.za Publisher: Karen Grant Deputy publisher: Wilhelm du Plessis Cover design: Air Liquide Production & layout: Darryl James Circulation: Brenda Grossmann Printed by: Tandym Print, Cape

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Air Liquide has developed an onsite stockmanagement solution to cater for welding and cutting customer needs. The container-based weld- ing store offers ISO 3834-compliant temperature and humidity control for welding consumables along with real time monitoring for the control and management of stock. African Fusion talks to Mwali Kawawa, the company’s newWelding and Cutting manager andRolf Schluep, Packaged Gas businessmanager for Air Liquide in South Africa.

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SAIW: Sean's comment

SAIW and SAIW Certification

I t is rather concerning that the future of the fabrication industry remains so unclear. Our industry is in survival mode, with fab- rication facilities downscaling as Medupi and Kusile near completion. From next year, it is expected that Medupi will reduce down to 300 workers onsite, with Kusile following shortly after. We hoped that the two rail projects, the PRASA Fleet Renewal Pro- gramme and the Transnet Freight 1064 project would fill the void leftby the completion of the power generation projects. Unfortunately these projects are now also mired in controversy and difficulties. In spite of a lot of training effort by the OEMs, most notably, Bombadier, the output to date has been very slow. Also of concern is that our private railway industry has not fully benefitted from these projects and, to a certain extent, has been kept at arms length from much of this work. Of late there has been much negative media coverage about the slow progress. With excess capacity in industry, this is rather disappointing. So where are we headed? Are we watching history repeat itself, seeing a fabrication industry falling apart once again? Looking at the positives, many people have been trained and capacity building has happened, with some success. In our industry, we now have a lot more welding engineers and technologists, QC personnel andwelding inspectors. As an industrywe have also trained many more welders, although skills at this level remain problematic. Our petrochemical industry, mostly through Sasol, has an obvi- ous future because it manufactures fuel from local coal and gas. The oil price is also increasing, which is a positive for fabrication. While problematic for consumers, a higher oil price justifies more explora- tion, upgrades and new plant investment, which are all good for the welding industry. Long term, our economy needs amanufacturing-based economy in order to provide employment opportunities, particularly for our soci- ety, which has a large proportion of unemployed youth. So it is deeply concerning that, in spite of more positive sentiment, manufacturing declined by 6.4% in the first quarter of this year. Highly skilled personnel are at the heart of a successful manufac- turing industry. We are, therefore, excited and continue to support the DHET’s Centres of Specialisation project, with its focus on the 13 priority trades, welding being one of them. We believe this will help to support the South African economy. We also need to face some hard facts. The biggest downside of our economy is poor productivity, which is nowhere near world-class levels. We desperately need a better-motivated andmore cooperative workforce in order to change this. A highly skilled workforce is the only way to sustain the manu- facturing and fabrication industries. It is imperative that we focus on puttingwell trained and highly skilled people into good quality jobs so they can produce quality products that are globally competitive. The welding industry can provide those jobs, but we need infrastructure development and projects to stimulate the demand for these skills. This is at the heart of transformation. Nelson Mandela said: ‘Edu- cation is the most powerful weapon which you can use to change the world.’ This needs to be a mantra in our society. We need to raise our efforts in education and training so that we can get more competent people into high-level positions. Welding is anenabling technology that canproduce abetter quality of life, because it involves decent paying jobs and lifelong careers. And welding skills are needed everywhere in the world. The AWS predicts a welder shortage of 400 000 in the US by 2024. Sowelding can be a core part of addressing transformation issues, restoring our manufacturing base and delivering a better life for all. Sean Blake

SAIW Governing Board President: Morris Maroga – Eskom S Blake – SAIW L Breckenridge – CEA G Joubert – SAISI A Koursaris – Metforensics DJ Olivier – Olivier Survey Group A Paterson – University of the Witwatersrand T Rice – Personal member J Tarboton – SASSDA JR Williamson – Wilconsult J Zinyana – New Age Welding Solutions SAIW Certification Governing Board Chairperson: G Joubert – ArcelorMittal B Beetge – Sentinel Inspection Services P Bruwer – Sasol Synfuels F Buys – TUV S Blake – SAIW G Buitenbos – Steinmüller G Joubert – SAISI A Koursaris – Metforensics D Olivier – Olivier Survey Group H Potgieter – SAIW Certification P Pistorius – University of Pretoria R Williamson – Wilconsult J Zinyana – New Age Welding Solutions M Maroga – Eskom S Moodley – SAPREF

SAIW Foundation Board Chairperson: M Maroga - Eskom S Blake - SAIW P Pistorius - University of Pretoria P Venter – ArcelorMittal J Pieterse- Afrox

SAIW and SAIW Certification representatives

Executive director Sean Blake Tel: (011) 298 2101 sean.blake@saiw.co.za

Training services manager Shelton Zichawo Tel: (011) 298 2148 shelton.zichawo@saiw.co.za

SAIW Certification manager Herman Potgieter Tel: (011) 298 2149 herman.potgieter@saiw.co.za

NDT training manager Mark Digby Tel: (011) 298 2169 mark.digby@saiw.co.za

Executive secretary Dimitra Kreouzi

Technical services manager Riaan Loots Tel: (011) 298 2144 riaan.loots@saiw.co.za

Tel: (011) 298 2102 Fax: (011) 836 6014 dimitra.kreouzi@saiw.co.za Finance and administration manager Michelle Warmback Tel: (011) 298 2125 michelle.warmbank@saiw.co.za Cape Town branch manager Liz Berry Tel: (021) 555 2535 liz.berry@saiw.co.za SAIW regional representatives

KZN branch manager George Walker Tel: (087) 351 6568 george.walker@saiw.co.za

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SAIW: 70 years of progress

70 years on: the SAIW president looks back In the year of 70th anniversary, current SAIWpresident, Morris Maroga, takes a look at how far the Institute has progressed since 1948.

L ooking back and thinking about our organisation, the Southern Af- rican Institute of Welding (SAIW), I was struck by the fact that, amongst all the things that happened in the year 1948, it was the year that the SAIW was founded and the year the Nationalist Apartheid government first came to power. What a momentous year 1948 was in the history of our country! South Africans were led down a path of hatred and divisiveness by a government that was tobecome reviled theworldover. Its policy of discrimination and deprivation caused untold harm, which will take generations to fully recover from. Yet, even from those dark times, organisations arose that have become key to the empowerment of millions of South Africans – regardless of race, colour or creed – through education and skills training. One such organisa- tion was the SAIW, which has become the leading welding training company in Africa having over the years trained thousands of people from all over the continent, with most having been able to get a job either in their home country or abroad. This is amagnificent achieve-

ment of which I am extremely proud. It is obviously true that, like all South African educational – and other – insti- tutions, the SAIW needed to become a relevant post-apartheid organisation through the requisite transformation. In this regard, while I acknowledge there is still work to be done, I am pleased to be able to report that our manage- ment, teaching staff and students today represent the full gamut of South African society and are all dedicated to making a difference in South Africa by providing both our youth and the more experienced personnel in our industry an opportunity to get ahead in life. One of the most pleasing factors of the SAIW 70 years on is how our influ- ence and involvement on our continent has grown beyond recognition. A good example of this is an initiative where, together with the Nigerian Institute of Welding, the SAIW is building The Weld- ing Federation of Africa (TWFA) to ensure the standards of welding are at globally accepted levels throughout the African continent. Regarding Africa and beyond, the SAIW recently became part of a power- ful international welding alliance – The

SAIW president, Morris Maroga.

International Alliance for Skills Devel- opment Belt and Road including BRICS – which aims at incorporating all the countries in this region in a cooperative initiative to provide welding training to the youth. Some of the countries that will be working closely together in the alliance are: South Africa, China, Russia, India, Ukraine, Singapore, Philippines, Cameroon, Ghana, Nigeria and others. From a global perspective the SAIW was, from its inception, part of the inter- national welding fraternity, having been a founder member of the International Institute of Welding (IIW) in 1948. Our relationship with the world’s most im- portant welding body has never faltered and in 2003 we became an Authorised National Body (ANB) of the IIW offering the full range of IIW qualifications – En- gineer, Technologist, Specialist, Practi- tioner, Welder and Inspector. Of course, accreditation is para- mount to our ability to provide our graduates with the best possible edu- cation and, apart from IIW recognition, we are also accredited by the Quality Council for Trades and Occupa- tions (QCTO) as per the South African National Artisan Welder programme that has recently been introduced. We believe that we are the first organisation to be accredited to this programme and the SAIWwill continue to gain accreditations to QCTO qualifica- tions and programmes as they become available. The South African National Artisan Welder programme has been developed such that it is aligned to our IIW International Welder programme to ensure compatibility and rec- ognition with this internationally recognised trainingprogramme for the development of South African citizens. Also, SAIW training pro-

“Our management, teaching staff and students today represent the full gamut of South African society and are all dedicated to making a difference in South Africa by providing both our youth and the more experienced personnel in our industry an opportunity to get ahead in life,” says Maroga.

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SAIW: QCTO apprenticeship

that it is incumbent on the SAIW to adhere to the international standards to which we are accredited.

Institute of Welding (NIW), in their quest to ensure world-class quality and ad- herence to global standards across the African continent have launched The Welding Federation of Africa (TWFA). According to SAIWexecutive director, Sean Blake, the main objective of the TWFA is to promote International Insti- tute of Welding (IIW) policies, systems and programmes inWelding Technology in Africa and to work towards regional and international harmonisation of personnel training, examination and certification systems in Africa. He adds that promoting collabora- tion between African countries in all mat- ters of common interest relating to the development anduseofwelding technol- ogy is also an important objective. “Working together will ensure that Africa reaches its full potential in becom- ing a respected and sought after region in the global welding technology space,” he says. Some other goals of the TWFA in- clude: • Organising African regional con- ferences on research and the ap- plication of welding technology at intervals of amaximumof four years. grammes and personnel certification programmes are recognised by the Department of Labour (DOL) for regis- tration of certified Pressure Equipment Inspectors for manufacture, repair and in-service inspection. In the interest of fairness and good governance, all SAIW’s qualification and certification programmes are ad- ministered by a separate not-for-profit company, SAIWCertification, and all the examination and certification activities for the various SAIW programmes are conducted by this company, which is accreditedby the South AfricanNational Accreditation System (SANAS) for per- sonnel certification to the International Standard for Personnel Certification: ISO 17024. We live in challenging times eco- nomically and I receive many letters asking about the prices of the courses asmany people have difficulty in raising the fundsneeded. This canbeaproblem, no doubt! But it must be remembered

I am pleased to say that we are doing our best to help as many as possible of those who genuinely cannot afford an SAIW education.

welding and related technologies; and more. In the first two years the SAIW Foundationhadmore than 10 graduates successfully complete internationally recognised programmes. So, in the 70 years of its existence, the SAIW has become an organisation that is known globally for its quality. Wherever one goes in the world the SAIW is known by those in the welding and related industries. Locally we are real hedge against unemployment for those who successfully complete our programmes. This is indeed a feather our cap! I want to thank all those who have contributed in some way to the success of this great institution of learning and I look forward to the challenging and exciting years ahead.

This requires the best possible teach- ers and equipment and all that costs money, which we have to raise, firstly, through privately-paying students and, secondly, through selling corporate and private memberships. The bottom line is that, being a not-for-profit company, remaining financially viable is always a challenge for the SAIW. I ampleased to say that we are doing our best to help as many as possible of those who genuinely cannot afford an SAIW education. One of our important initiatives is the SAIW Foundation, which was cre- ated in 2016. This is a public benefit organisation, which provides training to disadvantaged individuals in a wide range of areas including: welding and inspection; the training of trainers for

The Welding Federation of Africa launched T he Southern African Institute of Welding (SAIW) and the Nigerian • To encourage and participate in regional research and development activities. • To encourage the formation of weld-

• Establish a system of honorary awards to recognise exceptional con- tributions made to Welding in Africa by organisations and individuals. • To be the regional representative for Africa in the international welding community. “Our hope is that the TWFA will help Africa take its rightful place as a leading player in the welding technology world. We have the skills and the drive and I see no reason why this should not happen very quickly,” Blake says.

ing societies, including national welding societies in countries where such organisations do not exist. • To provide a platform for the organ- ised exchange of scientific and tech- nical information and to encourage andsustain the transfer of knowledge and technology through adaptive and innovative research in Africa.

At the signing of the TWFA Constitution are, from left: Ayo Adeniyi, NIW; Herman Potgieter, SAIW Certification; Sean Blake, SAIW executive director; and NIW President, Sololoman Edebiri.

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SAIW bulletin board

Naledi Pandor boosts Centres of Specialisation organisation in Africa, has been awarded the contract from the DHET to act as the ‘Quality Custodian’ of the process in the welding industry.

QCTO programme, which ultimately puts pay to the failed ‘Learnership’ idea. This is an excellent thing for thewelding industry and all other trades in South Africa,” Nell says. One of Nell’s first tasks was to find the two welding TVET partners and, after visit- ing several colleges, the Boland College in Worcester and the East Midlands College inUitenhagewere selected. These colleges will run the QCTO’s ‘dual’ training system, which combines technical education and practical training with authentic work ex- perience in a fabricator’s workshop. Meanwhile the National Skills Fund has set aside R150-million to support the partner colleges across all the sectors to ensure they are up-to-date and ready for training. For the welding industry, it will be Nell’s responsibility to help the two chosen colleges to procure the equipment, train the trainers and generally ensure that their infrastructures are in the appropriate condition for training. SAIW executive director, Sean Blake, says that Minister Pandor’s support of this programme iswonderful news for theweld- ing industry. “The Minister has said that national associations have a key role to play in modernising TVET colleges’ system for the production of intermediate-level skills and the SAIW is certainly ready to rise to the challenge,” he says. He adds that bringing together of all the right players, including the various industries, government and business, in a cohesive programme will do wonders in helping to improve the skills situation in this country. “This is long overdue and the SAIW is commited to doing all it can to make the initiative a success,” Blake concludes.

D epartment of Higher Education and Training (DHET) Minister, Pandor, at a recent meeting with captains of industry, has emphasised the importance of the department’s training initiative to boost youth employment in South Africa. Re- ferred to as the Centres of Specialisation (COS), the programme aims to secure partnerships between industry and 26 Technical and Vocational Education and Training (TVET) colleges, countrywide, for the training of top artisans in 13 priority trade sectors. One of these sectors is welding and the Southern African Institute of Weld- ing (SAIW), the leading welding training

SAIW’s EtienneNell has beenappointed the industry’s Occupational Team Conve- ner for the implementation of the Quality Council for Trades andOccupations (QCTO) Artisan Welder Curriculum (NOCC – A21), which, within the Centres of Specialisation, aims to produce: a skilled and capable workforce to support economic growth; an increased availability of intermediate skills; and an increased delivery of properly qualified artisan welders. “The Minister is fully committed to the

SAIW’s Etienne Nell, the industry’s Occupational Team Convener for the Quality Council for Trades and Occupations (QCTO) Artisan Welder Curriculum.

SAIW students awarded graduate diplomas A t the Southern Sun at OR Tambo on Friday, the 20 th April 2018, 62 successful students on SAIW and IIW Welding Inspec- tion and IIW Welding Specialist, Welding Technologist and Welding Engineer cours- es were awarded diplomas, with several being awarded more than one.

further 31 students also completed their IIW (Standard) courses, and a further three IIW Welding Technologists and three Welding Specialists are nowalso ready for entry onto the welding industry. To be at an SAIW Certification Awards Dinner is always an emotional experience. One is witness to people young and old changing their lives for the better. It is the ultimate justification of the effort that all the SAIW and SAIW Certification staff members and stakeholders make in order to ensure the best possible results for our most important assets – our students! Well done to all the graduates and to SAIW for its ongoing commitment to personnel and skills development.

With 2017 being the first transition year towards the International IIW IWIP suite of inspection courses, twelve IWIP Basic Cer- tificates and only six SAIW Inspector Level 1 certificates were awarded. Seven students received both Level 2 and IIW Inspection qualifications, with one student, Hendrik Jacobus Denysschen having completed his Level 1, Level 2 and IIW (standard) courses in the same year. A

Dorcus Mmule Matlala (right) proudly displays her IIW International Welding Inspection Personnel – basic level certificate.

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SAIW bulletin board

SAIW Online Student Management System launched logbooks that shouldbe completedat regu- lar intervals, vision acuity records that have to be updated annually and even changes in personal detail. Students will receive reminders to address annual surveillance issues aswell as reminders for certification/ renewal/recertification as stipulated in the relevant reference documents.

A s part of SAIW’s 70 years anniver- sary, both SAIW and SAIW Certifica- tion have decided to embrace the digital age and implement an Online Student Management system (OSMS). This forms part of a long-term strategy to provide an innovative, contemporary, paperless and industry-focused digital platform for SAIW’s trainees and SAIW Certification’s Qualification and Certification personnel. Phase 1 of this ambitious long-term project, kicked off in April 2018 with an invitation to all current students to log onto the system and confirm and upload infor- mation such as IDs, secondary and tertiary qualifications, CVs, photographs, etc. Initial access for students already with student numbers uses the student’s number as the username and ID number as the default password. New students are encouraged to register via the quick registration processwhich is easy to follow; but keep your cell phone or email account close-by since confirmationmessages and links requiring validation will be issued as you make progress. Later phases to be introduced include surveillance activities, which include online

Students or companies not having access to digital devices or the internet, need not worry, since the system still fa- cilitates manual bookings and the issue of any deliverables as per the current route. The normal process of booking should be followed with the relevant administrator booking the student onto the system and managing any interactionwithin the OSMS on your behalf. Students are encouraged to partici- pate during each phase and to send their suggestions, comments, complaints or compliments to quality@saiw.co.za. These inputswill be used to continuously improve the system and to make the interaction evenmore satisfying to SAIW’smost valued customers, its students. Tiredof losing records, lastminute rush to complete your experience logbook, not

receiving your confirmation, proof of train- ing record or examination results? The OSMS intends to resolve all of these issues. And since the online platform is governed by the Protection of Personal Information (POPI) Act, both access and uploaded records are controlled and the content is handled with absolute confi- dentiality.

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Cover story: Air Liquide

Connected store for onsite supply of gases and hardgoods

Air Liquide has developed an onsite stock management solution to cater forwelding and cutting customer needs. The container-basedwelding store offers ISO 3834-com- pliant temperature and humidity control for welding consumables along with real time monitoring for the control and management of stock. African Fusion talks to Mwali Kawawa, the company’s newWelding and Cut- ting manager and Rolf Schluep, Packaged Gas business manager for Air Liquide in South Africa.

“ A ir Liquide has always incor- porated value added ser- vices in its offers and thiswas clearly evident with the launch of the ARCAL TM New Generation range of weld- ing gases. With the release of this offer, a foundation was set for customers to benefit fromprocess optimisation, busi- ness efficiency and competitiveness,” begins Schluep. The ARCAL TM New Generation range consists of four premium shielding gases for arc welding namely; ARCAL TM Prime, a high purity argon gas for TIG and MIG welding of non-ferrous materi- als and back purging for stainless tube

volves the supply of Air Liquide’s ARCAL welding gases as well as a full range of consumables, machines and hardgoods needed to complete welding construc- tion, fabrication and repair,” continues Kawawa. “In essence, the container will be deployed in parallel to our gas offer and stocked with everything needed within 5 m around the welder to enable the welding to be completed efficiently, cost-effectively and timeously,” he adds. From a gases and consumables perspective, Kawawa explains that the management of stock is avery important issue. “In order tominimise defects and downtime, welding consumable stores need to comply with the requirements of the applicable codes of construction, client specifications and ISO3834. These specify the correctmanagement, control and issue of the consumables for weld- ing using the correct WPS, for example – and while these issues are very well articulated in ISO 3834, they remain challenging on almost every steel con- struction workshop and site,” he notes. “We have come up with an ideal solution to meet all the site-based welding needs, while complying with construction codes and standards such as ISO 3834,” says Kawawa. “We supply a 20-ft/6.1 m stock container with the stock management technologies re- quired to store consumables under the necessary conditions and to issue stock in a controlledway. This avoidsmistakes pertaining to recording and communi- cating the quantities and consumption levels,” he explains. “It is important when storing elec- trodes that moisture pickup is avoided so, unless vacuum packed electrodes are being used, the humidity and tem-

welding; ARCAL TM Chrome, amixture for MAG welding of stainless steel; ARCAL TM Speed for thinner section carbon steel welding and ARCAL TM Force for thicker joints requiring higher heat inputs. “We believe that at least 80% of all gas-shielded welding fabrication tasks can be successfully completed with the aid of one of these New Generation gases,” says Schluep. “Apart from this premium offer, we have developed a range of associated equipment, packaging and supply op- tions to help our clients further enhance their production processes. These include, amongst others: value added gas audits for the welding processes used; skid-based supply options with telemetry to enable automatic reorder- ing; our EXELTOP TM cylinder-integrated double stage regulator and flow control solution; as well as thewelding techni- cal support we have always offered to our customers. “Our increasing focus on cus- tomer centricity, along with the integration of our hardgoods offering from Weld-Cut into Air Liquide South Africa, has led us to extend our onsite supply solution. This includeswelding consumables such as electrodes, fluxes, wires, as well as the machines and all the accessories required to keep welding operations productive at a customer’s site,” Schluep tells African Fusion . The new offering for both work- shop and onsite operations is a container-based welding store

Air Liquide’s next- generation EXELTOP TM cylinder-integrated double stage regulator and flow control solution is just one example of an innovative solution tailored around customer needs.

that will provide easy access for welders involved in the fabrication and construction industries. “This offering in-

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stock control systems then updates the remaining stock levels. “Underpinning this offering is the real time telemetrymonitoring solution. Should any logic or control parameters be breached, the system will notify the site supervisor via SMS or email and can even lock out the user. The system can be modified to allow various levels of control and can be programmed to suit the ever-changing needs of the cus- tomer. A detailed record of the welder’s activity is immediately available for the project managers, which enables them to effectively and effortlessly control their inventories and better monitor their welding activities and costs,” sug- gests Schluep. “Another advantage is that invoicing only happens after resources have been allocated, so there is no need for the cli- ent to invest in welding resources in ad- vance, meaning that only the products actually consumed during the project are invoiced,” adds Kawawa. “Air Liquide is endeavouring to be- cominga customer-centric organisation. We are not only focused on fulfilling the gas needs of our customers but looking at delivering holistic serviceswithadded value,” says Schluep. “Our new Connected Store is tai- lored around the customer; we askwhat is required, what is preferred and how we can help to deliver a cost-effective and efficient welding service. With this in mind, we plan to evolve our value-added offers based on the needs of the market,” he concludes.

the consumables, machines, hardgoods and gas needed. Every construction contract is different, so we tailor the contents of the container store to meet the actual project needs. “The idea is that welders and weld- ing coordinators can have access to everything they need to complete their work more efficiently while offering control to the sitemanagement through real timemonitoringof stockwithdrawal activities. We take over all the stock management and control issues of the welding contractor and guarantee compliance to codes and specifications,” Kawawa informs African Fusion . Describing how Air Liquide arrives at a customised solution for custom- ers, Kawawa says the process starts with meeting the Welding Fabricator to identify their requirements. If support- ing a shut-down, for example, which has a well defined limited duration, we can forecast andanticipate everythingneed- ed to complete the work,” he explains. “We can also take care of the certi- fications needed by the plant operator: Some gas and consumable choices are essential variables for a WPS, so we will re-qualify procedures that explicitly name the consumables used,” he says. Advantages also roll over onto the commercial side: When a welder comes to the store, he has to enter his unique pin number into the stock control sys- tem prior to the order being processed. The Air Liquide store manager will then allocate the items to the job and issue the items to the welder. The automatic

perature inside the storage environment need to be maintained to keep fluxes and electrodes moisture-free and suit- able for use,” he continues. As well as maintaining the tempera- ture and humidity conditions at suitable levels in the container, electrodes and fluxes that have exceeded their exposure limits can be returned for baking. “The entire container temperature andhumidity is continuouslymonitored, via telemetry and this data is remotely tracked on a real time basis by Air Liq- uide. Warnings and alerts are then sent to the store manager and/or onsite welding supervisor to alert them of any deviations,” Kawawa continues. Over and above the notifications on the storage environment, the telemetry warns the assignee on the misuse of the product or abnormal activities. For example, if a worker is only allowed one pair of safety boots for the duration of a stipulated project but decides to order two, a notification will be sent to the assigned supervisor/manager. With respect to brands, Air Liquide has signed a supply agreement with ESAB for its Tier 1welding consumables, machines and accessories. “With this arrangement in place, we can offer a complete solution to our customers while offering the piece of mind that there are automated controls in place to ensure effective stockmanagement,” adds Schluep. “Our Connected StockManagement Tool is ideal for deployment during a shutdown because we can include all of

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New approaches to NDT

Presenting at the NDT Conference hosted by SAINT earlier this year, Tony Paterson high- lights the need for adopting new approaches to NDT in response to newmaterials and new operational imperatives, such as life extension drives and the health issues associatedwith the triple bottom line: planet, people and profit. NDT challenges relating to new materials, health and life extension projects

N on-destructive testing (NDT) is a wide group of analysis tech- niques used in the science and technology industries to evaluate the properties of a material, component or system without causing damage. Because NDT does not permanently alter the article being inspected, it is a highly valuable set of techniques that can provide assurance and save both money and time in product evaluation, troubleshooting, and research. Welding is a natural discontinuity as a cast structure is used to connect wrought parent materials. There is also scope for procedure and human errors. Failure in the heat-affected zone (HAZ) is a more common mode of failure. Hence NDT considerations paymuch attention to welds. The NDT role of providing assurance faces challenges into the future and may require some reassessment. This arises from operating circumstance changes. Also engineering materials have changed significantly, along with the late 20th and 21st century effects of globalisation, this including health and global sourcing.

results in larger deflections.

In no way restricting NDT, the future may well require amore systematic and regular assessment as residual life is as- sessed or as life extensionmodifications are considered in the face of ‘sweating the assets’. NDT will become more not less important. Consider engineeringmaterials. As a re- sult of various pressures, discussed be- low, the method of achieving structural (and other) steel mechanical properties changed significantly over the last 20 years. Whilst it has beenwell understood that steels can be strengthened through twomeans, composition and tempering through mechanical breakdown and thermal treatment – the latter includ- ing normalising, normalised-rolled, the thermomechanical rolling process (TMR) and Quenched and Tempered steels – hot rolled steels remained dominant. The new stronger materials have enableddesigners todesign lighter structures. However, there is a cost. As the Youngs Modulus remains constant, the lower sectionmodulus, Z, achievable Engineering material development

The motor industry, a very signifi- cant steelmarket, led theway to change. By the late 1980s Californian envi- ronmental legislation forced change on the motor industry by placing a premium on fuel efficiency, effectively placing a premiumon vehiclemass. This initially led to a motor industry move towards aluminium– aluminiumhas in- creased eight fold per vehicle from1975 to present to around 200 kg/vehicle. The steel industry responded by developing new, stronger steels andwonparts of the market back. From a structural engineering point of view, new stronger tempered steels were introduced. These included the commonly used S235, S275 and S355 grades, the S designating steel, the numbers minimum yield strengths for sections less than 16 mm thick. As the composition of all grades is near identi- cal, it is clear that grain refinement and/ or tempering determines the difference in performance. One question we seek to assess is the impact of welding on themoremod- ern materials and whether current NDT methods address these, whether it is suf- ficient to check for discontinuity alone when the welding temperature rises well above the transition temperature. Another area that has seen signifi- cant change includes the creep-resistant steels where the newest steels require both pre-weld and highly structured post-weld heat treatment. In addition the product life cycle for structures is often in excess of 50 years, with over 100 years not uncommon. Creep only shows up after extendedperiods of exposure to high temperatures and high pressures. Globalisation has enabled purchase worldwide. The steel industrydeveloped separately in different parts of a then isolated world. It developed differently in different countries. The products de- veloped for specific purposes were not identical. Many different countries developed local steel compositions,

Figure 1: Process plants are typically made up of tanks, heat exchangers, distillation columns, pumps and interconnecting thin wall pipes.

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Figure 2: The formation of biofilm and its effects on bacterial growth. Source: A review of current and emergent biofilm control strategies; Manuel Simoes, Lucia C Simoes, Maria J Vieira; LWT – Food Science and Technology 43 (2010) 573–583).

specification route. Having noted this principle, the EN standards for welding have become closer to method speci- fications. Based on (international) standards, administration has become the driver rather than the facilitator. Checklists su- persede appliedengineering skills, while inspectors have replaced supervisors. Consequently, quality tends not to be built in but inspected out. Resource limitations, particularly related to materials coupled to energy use and global warming have encour- aged manufacturers to use significant quantities of scrap as an input material. This has the advantage of reducing the energy (and hence water) requirement, so mitigating against global warming, while recognising the finite limits of materials. Whilst in principle this is not a problem, extensive scrap use requires different, higher, levels of control in terms of collection, grading andmelting. Operational changes Life extension responds to the second aspect cited, the operational circum- stance changes over the past 20 to 30 years. These include: • Globalisation. • The triple bottom line of planet, people, prosperity (e.g. Interna- tional SHE). • Global warming. • Internet/digital design aids/en- hanced communication tools. • Resource limits: The finite limits of engineering material availability; limits of energy sources; and water resource limitations. The strategy of sweating the assets: Life extension What does ‘sweating your assets’ actu-

ally mean? The term came out of the manufacturing industry. Usually it’s thought about in terms of machinery, fixed assets and physical equipment against their criteria of optimal use. Time is a measurement issue here. Consider these asset groups: build- ings/space, machinery and people: • If a fixed asset such as a building, plant, structure or large area of space is owned or rented, sweating this asset implies getting the most out of it. Leveraging fixed asset ca- pacity may be an important issue. Can the asset be usedmore or more effectively? • The next asset class is machinery. Large expensive machinery, equip- ment and plant really need to be used as much as possible to de- crease their unit cost. • The less obvious side of assets is people. Sweating people assets implies maximising the capacity of people. This could involve resizing or retraining. The use of time has been noted above. It also implies working existing assets either beyond design life or under dif- ferent operating conditions. To get themost value fromhigh-val- ue assets such as production facilities, there is a need to find the right balance between maintenance, modernisation and operational activity so as to extend service life, enhance performance and minimise ‘down-time’ over the asset lifecycle. In Johannesburg, one example of sweating the assets is the practice of increasing water pressure even beyond design pressure to facilitate service delivery to an increasing population. Clearly failures are to be expected – the weakest link will break first.

tempers, designations and standards. This makes steel selection more com- plex than one would prefer. The identification of performance equivalence is not always easy, even between manufacturers in the same country quite apart fromglobal imports. Globalisation has also encouraged inter- national standards, generally drawn up from developed countries’ lead. Some are input defined, others performance defined, a difference in philosophy. This challenges theNDTprofessional in terms of interfaces betweenproducts supplied to different standards. It is not always as simple as ‘use the most conservative approach’. Steel designations are important as they help choose correct material for the specific operating circumstances considered. They also help in choosing the correct electrode for the material and welding position. However, in seeking to take advan- tage of the commercial opportunities of globalisation, buyers are faced with the reality of a range of internationally recognised country standard designa- tions, locally recognised local grade/ alloy standard designations, and indi- vidually recognised manufacturer or stockist designations. The reality on site is that apparently similar materials may perform differently. In teaching, we recommend that if a different sup- plier to the one against whose product weld procedures are developed, test the new product against the existing procedures to ensure procedure and process relevance. From a systems control point of view, input (method) specifications are preferred to output (performance) specifications. But South Africa has chosen the EN route, the performance

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New approaches to NDT

complywith increasingly onerous health legislation introduced over the past two decades or so. The legislation limits ac- ceptable bacteria and spore counts in the final product. A major constituent of most products is water. As private sources of water have declined, more and more use is made of municipal water. This is of inconsistent quality over time. Product input materials are shipped fromsources often far removed for the process plants. These generally differ per batch. Bacteria are directly associatedwith the build-up of bio films on product con- tact surfaces. Welded surfaces include geometric and surface effects, which may encourage biofilm development. Clearly some of the existing process plants often designed prior to new leg- islation will be in early to mid-life. Biofilms formon the exposed surfac- es of process plant (See Figure 2 below). A thin layer of microorganisms adheres to the surface to form the film. This may be organic or inorganic, together with the polymers that they secrete – and biofilms include bacteria. Biofilm depth increases with in- creased surface roughness, increased temperatures, and lower flow speeds (note occluded and dead area effects). One source of surface roughness and local occlusions are welded joints. Resulting from biofilm formation, bacterial growth develops and is re- leased into the product. Biofilm forma- tion on inside surfaces encourages bac- teriagrowthanddepresses theminimum inhibitory concentration (MIC). Weld imperfections, therefore, have a direct impact onhealth–andbiofilmformation is not limited to health related sectors. The depth ( δ ) of the film also in- creases with increased surface rough- ness, increased temperatures, and lower flow speeds. Sequential biofilm formation can be summarised as follows: (1) Attachment of small organic mol- ecules to the surface. (2) Microbial cells deposited on and adsorbed into the forming layer. (3) Cells produce hair-like exopolymers (fimbriae) , which feed on organic matter. (4) Biofilm layer grows and includes bacteria. (5) Product flow degrades some of the formation. (6) An equilibrium layer of depth δ is formed. This depth increases with

Older assets operated for decades are of older materials and older design. Consequently themaintenance ormod- ernisation needs to take different design standards, different material standards and different human skill levels into account. The practice of life extension, part of ‘sweating the assets’, may well mix older manufactured materials with newer. Also the reduction in manpower has often affected corporate memory. Corporatememory, the ‘knowledge and information from the companies past that can be accessed and used for pres- ent company activities’ (Railway Inves- tigation Unit, 2010), is not always avail- able and/or accessible. With changed personnel and/or poor record keeping or access, corporate memory loss can prove important when considering life extension. The aspect of corporate memory loss may become significant in assessing NDT needs. What is the weakest link? when will it break? how can life be extended? Cur- rently one problem that is emerging is delamination on pressure and thermal vessels and pipes. Others have been noted in welds. Roll refurbishment that seeks to add wear-resistant layers risk delamination if not properly assessed. Whilst clients want to extend life, indus- trial research using NDT, appropriate tools are increasingly required. The triple bottom line – planet, people and profit – health issues Chemical engineers manufacture prod- uct on a commercial scale. Technology has made life simpler, safer and more convenient. With increasing urbanisa- tion, the C20 th introducedprocess plants tomass-producepharmaceuticals, food, beverages, wine and beer. Concentra- tion was on optimising cost, time to market and reliability. Solutions were financial and technical. But the C21 st has introduced other demands fromwelded fabrication. Triple bottom line reporting places emphasis on the suite of people, planet and prosperity. In particular health is- sues have become more relevant. Inter- nationally and locally, health legislation has been progressively tightened in the pharmaceutical, dairy, food, beverage and brewery sectors. So whilst criteria used to focus on structural integrity, the need for hygienic fabrication adds a new dimension to NDT needs. Process plants are typicallymade up

Figure 3: Scanning electron micrograph of a biofilm on the inner surface of a dispensing line. A: protruding fimbrae; B: Yeast cells; C: Bacteria. Source: Erna Storgårds; Process hygiene control in beer production and dispensing; VVT publication 410 2000. of tanks, heat exchangers, distillation columns, pumps and interconnecting thinwall pipes. In addition, a second set of piping is required to facilitate Clean- ing in Place (CIP) without disassembly. Typically, many components arewelded together. Whilewelding an enabling technolo- gy, process plants are often now subject to health legislation with demanding hygienic requirements that are often difficult to achieve, particularly onsite. Production hygiene is required to guarantee medicine and food safety. Complete sterility of plant, input mate- rials and water is the ideal, whilst not a realistic expectation. In the absence of complete sterility, other methods need tobe considered for plant establishment or refurbishment practices to eliminate or mitigate against bacterial load. For hygienic fabrication, whilst good design standards exist, major gaps are found in the lack of practical guidelines, educationand, pertinent toSouthAfrica, skills traininganddevelopment together with appropriate supervision. Tanks, distillation columns and heat exchangers are factory-built from stan- dard flats and shapes welded together into the required form. The focus on product quality is high. However,most of the small bore thin wall pipe inter-con- nections are made on site. These pipes are inaccessible from the inside. Site welding is inherently farmore difficult to control partly because of the operating circumstances and because of the focus on the production schedule. Inadequate welded joints can compromise product quality in an otherwise hygienically de- signed plant. Poor joints and/or welding can trap biofilm, the source of bacteria. Theymay also lead tomicrobial induced corrosion and/or stress corrosion crack- ing, both of which would potentially affect hygienic performance. Both existing and new food, bever- age and brewing process plants need to

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