African Fusion August 2019

AFRICAN AUGUST 2019

Journal of the Southern African Institute of Welding

Contents

August 2019

FEATURES 4 SAIW and EAIW partner to develop Kenyan welders The East African Institute of Welding (EAIW), with the support of SAIW, has launchedawelder trainingprogramme to make local skills available for the crude oil pipeline connecting the Lokichar oilfields and the Lamu seaport on Kenya’s East Coast. 6 FP Engineering: a quality focused and proudly South African local fabricator African Fusion talks to Mark Potter of FP Engineering about his company’s proudly SouthAfricanattitudeand increasing focus on raising service levels and quality standards. 8 Welder-driven fabrication quality African Fusion visits the fabrication facilities of engineering, manufacturing, fabrication, machining, welding and refurbishment specialist, Turnmill Proquip Engineering and talks to the company’s welding engineer, Renko Huisamen about current and recent fabrication successes. 12 Quality is safety In this paper from the Bali IIW International Conference of 2018, Louise Petrick of Weld Australia draws from some catastrophic weld failures to showhowethics, weld quality management and engineering interact to ensure weld safety. 16 The role of gas for laser and plasma cutting Air Products’ welding specialist for bulk and packaged gas, Sean Young, talks about laser andplasma cutting processes and the critical role of the gasmixture in achieving required cutting speeds and edge qualities. 18 Fronius expands TPS/i platform with Steel Edition Fronius is launching its TPS/i Steel Edition, which has been optimised for manual steel welding and impresses with an attractive price/performance ratio. Users benefit from different characteristics for standard and pulsewelding, as well as aWPS package containing procedure specifications certified to DIN EN 1090. 21 SE Steel chooses Arcal Speed Mwali Kawawa and Lebohang Molotsi of Air Liquide visit the fabrication facilities of SE Steel Fabrication to find out about the advantages of using of Arcal TM Speed shielding gas. 22 Easy OHS compliance Zero tolerance is being exercised by the Department of Labour towards companies that do not comply with the health and safety regulations stipulated in theOccupational Health and Safety (OHS) Act. Wim Dessing, sales executive of Apex Strip Curtains and Doors, says this is particularly with regard to welding environments. 23 SSP: an integral part of Afrox’s 360-degree solutions Afrox’s Business Manager for Manufacturing Industries, Johann Pieterse, describes howAfrox’s full Safety Solutions Programme (SSP) has been incorporated into its 360-degree Solutions offering. REGULARS 3 Morris Maroga’s message 10 Front cover story: Specialised welding consumables for the sugar industry 24 Welding and cutting forum 28 Today’s technology: LIBS analyser: a world-first for carbon content.

Published four times a year and mailed out together with MechChem Africa by: Crown Publications (Pty) Ltd 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

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Deputy publisher: Wilhelm du Plessis Production & layout: Darryl James Circulation: Brenda Grossmann Printed by: Tandym Print, Cape

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UTP Maintenance, the voestalpine repair welding specialist, is a reliable supplier of welding consumables for the repair and arcing of cane crush- ing rollers used in the sugar industry. Kenneth Labuschagne of voestalpine Böhler Welding presents the com- pany’s purpose designed offering for the better protection of these rollers and production optimisation in the industry.

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Publisher of the Year 2018 (Trade Publications)

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www.africanfusionmagazine.co.za

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President’s message

SAIW and SAIW Certification

SAIW Governing Board President: Morris Maroga – Eskom B Beetge – Sentinel Inspection Services L Breckenridge – CEA J Guild – SAIW G Joubert – SAISI DJ Olivier – Olivier Survey Group A Paterson – University of the Witwatersrand J Pieterse – Afrox 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 – Consultant and SAQCC IPE G Buitenbos – Steinmüller D Olivier – Olivier Survey Group H Potgieter – SAIW Certification P Pistorius – University of Pretoria R Williamson – Wilconsult J Zinyana – New Age Welding Solutions

Morris Maroga’s message O ur economy is in difficulty at the mo- ment. Industries and companies are restructuring and many skilled em-

ployees are being offered retrenchment packages. The slowdown in construction started affecting the fabrication industry some 18months ago and many fabrication shops are still quiet. Quiet times can become opportunities to progress, however. By becoming leaner and better at what we do, not only will we be more sustainable andmore resistant to global economic variations, we can also become better able to compete for work in global markets. Fabricators can use the current quiet to focus on improving produc- tivity, product quality and their future capability. At the starting point of this is upskilling their people so that they are better able to deliver quality products and services when the economy finally turns around. As the SAIWpresident, it fillsme with pride when I see adverts from the Middle East and Southeast Asian countries that specify SAIW- qualified Welding Inspectors or NDT personnel. SAIW offers globally recognised training and qualifications, whichmeans that SAIWgradu- ates can work anywhere in the world. We would of course prefer our people to use their world-class skills to make South Africa the fabrication destination of choice for those north of our borders and overseas. I therefore urge fabricators with spare capacity to take advantage of the opportunity to improve the qualifications of their people so that South African fabrication is seen as world-class as well as its SAIW-trained people. World-class fabrication has to meet world class quality standards. I remember a time not too many years ago when Eskom and compa- nies such as Sasol would do technical assessments on any fabricator tendering for work to ensure that the bidders couldmeet internally set quality requirements. We no longer have to do these assessments, be- cause ISO3834 certification has become the newbenchmark of a good fabricator. Neither do companies need to be separately accredited for different clients. Instead, an ISO 3834 certificate accredits a company as complying to the global weld quality requirements that are needed. For those who have not yet joined the SAIW Welding Fabricator’s Certification scheme that certifies fabricators to ISO 3834, this is an- other downturn opportunity. Even small fabricators can take on this certification as the cost of becoming certified is not expensive at all. What has to happen though, is welding practices need to be aligned towards meeting the prescribed quality standards and the qualifica- tions of personnel may need to be upgraded. So I urge our local fabricators, from small to large, to use the op- portunity of these lean times to send people for further training, to put in place the changes required for ISO 3834 and then to become Certi- fied according to the SAIWWelding Fabricator’s Certification scheme. For us to progress, it is vital that all plant operators, fabricators and people whowork for themact in the interests of the whole country, its industry and its economy, rather than simply acting in their ownnarrow interests. I believe our country is best served by using local fabricators as much as possible, as the Chinese do. We will always need to import some products, but this should be a last resort and we should all be striving to expand our local capability however we can. Short termthinking doesn’t help anyone and yields only short term gains, but ifwe succeed inputting the economybackon track, everyone will gain for the foreseeable future. Without skilled people, it is impos- sible to realise anAfrican continent with thriving economies, peace and prosperity and there is no better time to upskill employees than now.

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

SAIW and SAIW Certification representatives

Acting executive director

Training services manager

Jim Guild

Shelton Zichawo Tel: (011) 298 2148

Tel: (011) 298 2101 Jim.guild@saiw.co.za

shelton.zichawo@saiw.co.za

SAIW Certification manager

NDT training manager

Herman Potgieter Tel: (011) 298 2149

Mark Digby

Tel: (011) 298 2169 herman.potgieter@saiw.co.za mark.digby@saiw.co.za

Executive secretary Dimitra Kreouzi Tel: (011) 298 2102 Fax: (011) 836 6014

Technical services manager

Riaan Loots

Tel: (011) 298 2144

riaan.loots@saiw.co.za

dimitra.kreouzi@saiw.co.za

Finance and administration manager Michelle Warmback Tel: (011) 298 2125 michelle.warmbank@saiw.co.za

SAIW regional representatives Cape Town branch manager

KZN branch manager

Liz Berry

George Walker

Tel: (021) 555 2535 liz.berry@saiw.co.za

Tel: (087) 351 6568

george.walker@saiw.co.za

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SAIW and EAIW partnership

The East African Institute of Welding (EAIW), with the support of SAIW, has launched a welder training programme for 70 welders tomake local skills available for the construction of a crude oil pipeline to connect the Lokichar oilfields in the Tur- kana Province of Northern Kenya and the new Lamu seaport on the Kenya’s East Coast. African Fusion talk to SAIW’s Shelton Zichawo and EAIW’s Ruto Lyoba about the initiative. SAIW and EAIW partner to develop Kenyan welders

SAIW’s training manager, Shelton Zichawo.

ing course, for which we at SAIW are the Authorised Training Body (ATB) for Southern Africa,” he continues. Williams spent four weeks in Kenya earlier this year delivering the two-week theoretical module to two groups of Ke- nyanwelders. The two trained Kenyans, Monica Mwalo and Nicholas Kiplimo, then went on to deliver the practical training component of the course to these young welders. “WillieWilliams has now just returned from Kenya where he spent a further three weeks doing the practical code testing of the welders to enable them to be certificated as International Welders by the IIW and according to ISO 9606-1 International standard, which speci- fies the requirements for qualification testing of welders for fusion welding of steels,” Zichawo tells African Fusion . “The EAIW intends to become an ATB in its own right for the East African region, whereby its employs its own qualified staff to train and accredit International Welders without SAIW involvement, and we in South Africa are more than happy to help them achieve that goal,” he adds. EAIW chairman, Lyoba, says that Kenya has recently discovered oil in the Tur- kana basin near the Great Rift Valley in northwest Kenya. “A pipeline is going to be built to transport crude oil from the Lokichar Basin in the Turkana oil fields in the northwest to the seaport of Lamu on Kenya’s east coast, which is also currently being constructed,” Lyoba explains. “We do not want to be importing welders to construct this pipeline or for the other associated infrastructure developments in our country, which is why we sent two of our employees to the SAIW in Johannesburg for advanced welder training. On their return we set The EAIW: local skills for local infrastructure

A 750-million barrel crude oil resource was discovered in the South Lokichar Basin near the town of Lokichar in Kenya’s Turkana province back in 2012, with subsequent exploration indicating 1-billion barrels may be present. So far the country has transported about 80 000 barrels at 600 barrels per day by road to Mombasa. A local refinery is not seen as viable to process the Turkana oil. Instead, Kenya plans to build its own 891 km pipeline from Lokichar to the port of Lamu. The crudewill then be exported to refineries in other parts of the world. The 80 000 to 120 000 barrels per day pipeline is mooted for completion by 2022at a total cost of cost KSh100-billion (about US$1-billion). “Our partnership with the East Afri- can Institute of Welding (EAIW) in Kenya began when we were approached to train two of their staff members late

last year,” says SAIW’s trainingmanager, Shelton Zichawo. “So two of their train- ers came down to the SAIW Training School in Johannesburg for practical welding training, with the intention of passing on these skills to welders in Kenya.” This was the beginning of a blos- soming partnership that has led to the establishment of a brand new welding school in Kenya for the delivery of IIW- accredited welder training. “From discussions with the EAIW chairman, Ruto Lyoba, we realised that this was the start of a welder training programme on a much larger scale,” Zichawo continues. “Following the training here, we helped the EAIW with the design of their new welder training school. Soon after, Willie Williams from our practical welding school went to Kenya to deliver the theoretical module of the IIW International Welder train-

The EAIWmanagement team, from left: Malcolm Marega, principal, Jane Lyoba, managing director and Ruto Lyoba, chairman.

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SAIW and EAIW partnership

EXECUTIVE DIRECTOR SAIW is the leading national resource for train- ing and technical support in welding and non- destructive testing. The Institute is seeking to recruit an individual who is capable of maintain- ing the Institute’s national and international standing and further developing the Institute’s presence and capabilities in national provinces as well as throughout the African continent. MF61EVK Minimum requirements  Technical Qualification, preferably BSc.  10 years related experience of which 5 years are at senior managerial level. Key responsibilities  Corporate governance and development of SAIW and its subsidiaries (SAIW Certification and SAIW Foundation).  Financial and administration oversight of SAIW group of companies.  Business development of SAIWgroup of com- panies.  Managing strategic national and international relationships.  Oversight of the management and develop- ment of operational activities. Requirements of the position  Knowledge of the Institute and experience in the fields in which it is active.  A successful record of businessmanagement.  Experience in new business development.  Ability to communicate and interact in na- tional and international forums.  Suitable qualifications and experience.  Optimism, focus and tenacity especially in challenging situations.  Strong interpersonal skills.  Sound knowledge of the policies, legislation andpractices that govern the operation of the Institute.  Thorough understanding of all aspects of Hu- man Resources. Candidatesmust bemature persons froma tech- nical background with a record of professional integrity, experience of leadership and people management skills. Applications should be submitted to Dimitra Kreouzi by email to kreouzid@saiw.co.za by no later thanFriday 27 th September 2019. All persons of interest will be contacted within a period of 15 days of closing date. Other candidates are thanked for their interest but should consider their application as unsuccessful.

Above: Training facilities include the practical training school with state-of-the- art welding bays and modern and fully equipped classrooms. Right: Graduating welders currently receive an IIW International Welder Diploma and Code certification to ASME IX and ISO 9609, all of which is are firsts for Kenya. up a state-of-the-art welder training centreandnowwehave70 students, five of which are sponsored by the EAIW as part of our way giving back to our local community,” he says. The Kenyan economy is becoming more and more sophisticated. With the discovery of oil and gas in Turkana and the emergence of renewable energy technologies in the form of wind and thermal energy. General manufacturing is growing, withmodern bottling plants being built and the country’s bulk road transport (BRT) programme becoming a reality. This has led to the increasing need for specialist coded welders and the EAIW was established in 2017 on the outskirts of Nairobi as a technical insti- tute dedicated to developing excellence in welding. “EAIW is in the process of becoming an ATB of the IIW, which is an international body seeking harmonisa- tion in the training, qualification and testing of welders around the world. We are now set up to offer MMA, MIG/MAG and TIG welding skills to local Kenyans so they can help us to improve our in- frastructure and growour economy,” he tells African Fusion . “We are passionate about the youth in our country.,” Lyoba continues. “Un- fortunately, many of them are unem- ployed and lack skill – and the skills gap is huge. There is a particular shortage of codedand specialisedwelding skills and this Institute is offering an opportunity for Kenya to develop its own skills base and to even start to export training

skills to other countries in our region,” he adds. “As a vocational training institute, we at EAIW are dedicated to delivering competency-based education and train- ing (CBET) to international standards. Training facilities include a practical training school with state-of-the-art welding bays and modern and fully equipped classrooms. “Graduating welders currently re- ceive an IIW International Welder Di- ploma and Code certification to ASME IX and ISO 9609, all of which is are firsts for Kenya,” Lyoba says. Currently focusing on specialist welder training inMMAMIG/MAGandTIG with a focus on steel and pipeline weld- ing, futureplans includeunderwater and robotic welding courses. “We are also actively encouraging women to take up welding as part of the broader initiative to see more women in careers that re- quire science, technology, engineering andmathematics (STEM) competences,” he adds. “We are excited to be part of a pro- gramme to uplift the skills in our people, our country and to contribute to our economic growth andprosperity,” Lyoba concludes.

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SAIWmember profile: FP Engineering

FP Engineering: a quality focused and

For our SAIW Member Profile this month, African Fusion talks toMark Potter of FP Engineering about his company’s proudly South African attitude and increasing focus on raising service levels and quality standards.

F P Engineering is an established South African Engineering com- pany with its head office and fabrication facility in Glen Anil, Durban, KwaZulu-Natal. “We specialise in steel fabrication and the manufacture of tanks, silos, pressure vessels, dryers, hoppers, materials handling equipment and platework for all types of plant,” Potter begins. At FP Engineering, we can offer de- sign, drawing, third party inspections, fabrication and installation services, either as part of a broader project team or, if required, as full turnkey projects,” he adds. FP Engineeringwas founded 40 years ago in 1979 byMark Potter’s father, Ron- nie Potter, who established a fabrication workshop to service the local sugar industry, fabricating and repairing sugar plant equipment suchas tanks, hoppers, and conveyor systems. “In the early years, we focused on sugar, which we still do today; but we have since come to offer fabrication services in all industrial

sectors such as mining and minerals processing, pulp and paper, water and wastewater, chemical and petrochemi- cal, cement and many more,” he tells African Fusion . “Today, the company is still run as a familybusiness,withmybrotherMichael and I running the business as directors. Michael takes care of production and fi- nance, while I am in charge of operations and marketing,” continues Mark Potter. With respect to facilities, he says that fabrication is done from a large fully equipped modern workshop and machine shop. “We have 5 000 m 2 un- der roof with full access to overhead craneage. We also have our own ma- chine shop, which avoids us having to outsource any of our manufacturing tasks, along with one of the bigger high definition water jet cutting systems in the country. With a 3.0 m x 12 m bed, this machine can cut through carbon steel 150 mm thick, giving us the capac- ity for very heavy fabrication when the need arises,” he says, adding that FP

Mark and Michael Potter, directors of FP Engineering. Engineering also has a 3 000m 2 laydown area outside. Turning attention to the company’s welding capability, he says FP Engineer- ing is equipped to meet the needs of all welding procedure specifications based on client and code requirements. “For thicker section, wedoa lot of submerged arc welding, while we prefer the semi- automatic gas metal arc and flux cored processes for thinner plate. We always adhere closely to the design though, and we allocate resources accordingly, with respect to equipment and welding skills,” say Mark Potter. With respect to the materials of con- struction, he says that FP Engineering can work with any materials chosen by the client. Carbon steel, boiler plate and all grades of stainless steel are routinely used and special epoxy coatings can also be applied, for example, to steel tanks such as those used for sewage treatment tanks. The same applies to welding skills. “We have a number boilermakers and welders that have beenwith the compa- ny formany years, but if we need specific skills for a particular job, we will put the word out in the industry and then ask the candidates to do qualification weld tests to ensure they can perform to the standards required,” he explains. “Whatever the job, we will make it work. If we need to add skills or other

FP Engineering fabricated and delivered four U-stamped pressure vessels for an oil and gas industry client in Angola.

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SAIWmember profile: FP Engineering

proudly South African local fabricator

Left: FP Engineering also offers full turnkey projects such as the design fabrication and construction of this animal feed plant. Right: A juice heater manufactured by FP Engineering for the sugar industry, which the company has serviced since its establishment in 1979.

learners. The TVET learners were will- ing to relocate to Durban to begin their in-service-training programmes at FP Engineering. “We have been hosting young graduates and trainees for ten years or so now. We believe in giving our local youngsters the best chance pos- sible to establish their careers by giving them some good experience that helps to make themmore employable. Notable projects? Potter says there are too many. “We are now very diversi- fied, so we have many success stories such as sugar plants, concrete batching plants, materials handling equipment, pressure vessels, animal feed plants, heat exchangers and specialised trailers. “Whilewe still hadour ASMEU-stamp certificate, we were one of the first local companies inKwaZulu-Natal to fabricate U-stamped pressure vessels for the oil and gas industry. We fabricated and delivered four of these vessels for a cli- ent in Angola. And for the sugar industry, we fabricated the first chainless diffuser in Africa, whichwas built here in Durban before being transported and installed at Illovo Sugar in Swaziland,” Potter responds. “We have a very good reputation for getting work done, timeously and decisively. And we are very proud to be a family-first business. We take our employees into consideration and invite their family members to work for us. Employee satisfaction helps people to thrive and ensures that our employees are motivated to perform the duties to the best of their abilities,” Potter concludes.

is the most important, though, that be- ing to complete the job on time and to specification,” he notes. A key advantage of ISO 3834, he believes, is that it differentiates FP En- gineering from those trying to undercut fabrication costs by cutting corners. “From a marketing perspective, our quality certifications assure clients that we are an established, reputable, competent and quality conscious fab- rications company,” he informs African Fusion . On the outlook for the fabrication industry, Mark Potter says that creating jobs has got to be the nation’s priority. “To create jobs, we need projects so we can employ more people. We would like to see our Government do more to encourage local manufacturing and to stop cheap imports of fabricated steel. Procuring locallymanufactured ‘Proudly South African’ equipment will create jobs – every truck body or pressure ves- sel sold enables us to employ four or five more people, while that doesn’t happen when importing,” he argues. “We are passionate about job cre- ation, whichmust be linked to skills. We therefore do a lot of in-service training here, for initiatives such as the P1 andP2 Engineers in Training (EIT) programme. In addition, we take in young trainees from artisan courses at TVET colleges to do work experience training in our facility, enabling our skilled staff to give back to the community by passing on their knowledge and experience.” At present we have six EIT students, four Learners from SAPREF and 15 TVET

resources to get the job done, then that is what we will do,” he adds. FP Engineering was first qualified to the ISO9001 (2008) qualitymanagement standard in 2011. “As a fabrication com- pany, we then went on to become certi- fied to ISO 3834: Part 2. This standard defines the quality requirements for welding and Part 2 is for comprehensive quality and covers critical fabrications such as pressure vessels. We completed this process in 2013 under the SAIW Welding Fabricators ISO 3834 Certifica- tion Scheme. “In today’s quality conscious environ- ment, ISO 9001:2015 and ISO 3834 certi- fication are necessities. ISO 3834 helps us to build quality into fabrications and acts as a clear guide to all thoseworking on a project about their role in meeting the specified quality. ISO 9001, on the other hand, outlines what we have to do tomanage and document our manufac- turing quality,” he tells African Fusion . “Locally and International, these two quality certificates are being recognised andacceptedasminimumrequirements for a fabricator to be considered when tendering for a project. They identify the systems that need to be in place to con- sistently produce qualitywork,” he adds. “We find it makes it much easier to introduce new people into our or- ganisation because we have clear procedures that they can be asked to follow. Procedures are continuously changing, to suit the work that comes in and technology advancements, and we are also routinely having to clarify grey areas that emerge. The end goal

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SAIW Member profile: Turnmill Engineering

Welder-driven fabrication quality

African Fusion visits the fabrication facilities of engineering, manufacturing, fabrication,machining, welding and refurbish- ment specialist, Turnmill Proquip Engineering and talks to the company’s welding engineer, Renko Huisamen about current and recent fabrication successes.

T urnmill Engineering is a medium to heavy specialist engineering company in Vanderbijlpark. The company was founded in 1980 by Carel Pienaar and was acquired in 2008 by Level 1 B-BBEE company, The Structa Group. The company’s commitment to customer service, high standards of workmanship and quality, service and on time delivery, and its competitive cost structures have enabled Turnmill to build sound long-term partnerships with blue-chip clients. “We manufacture a wide range of equipment in materials varying from boiler plate to stainless steel, duplex stainless steel and more exotic alloys. Being part of the StructaGroup, Turnmill Proquip Engineering also has access to the Group’s engineers and design pack- ages, including FEA design facilities throughour sister the subsidiary, Structa Konsult,” says Huisamen Originally founded in Vereeniging to service growing needs of the local pet- rochemical industry for heat exchangers

and process vessels, Turnmill’s core capability remains in medium to heavy fabrication projects. Huisamen first cites ongoing work on four giant uranium leach vessels destined for use by a mine in Rusten- berg. “These are huge constructions – 40 m long by 6.0 m wide and 5.0 m high – that look like massive versions of the vessels used for the D-day landings during the Second World War,” he tells African Fusion . Due to the size of these structures, manipulation for a more favourable welding position becomes impossible. “All the welding has to be done in posi- tion, which means there are lot of verti- cal and overhead seams. For these we have chosen to use a BOHLER Ti 71-T1M flux-coredwire, because the fast freezing slag enables the welders to control the weld bead shapewithout having to slow down the deposition rates,” he explains. Turnmill Engineering uses use Air Liq- uide’s Arcal Force argon/CO 2 gasmixture for this process as it contains more CO 2 than solid wire gas mixtures such as Ar-

cal Speed. This results in a tight arc that gives excellent fusion. “The gas and flux-cored wire combi- nation is very competitive with respect to cost and allows us to use our con- ventional MIG/MAGwelding equipment. We did look at solid wire pulsed-MIG welding for the job, but this would have involved new equipment investments and would not have been as fast,” he reveals. Describing his experience with flux- cored welding, he says that a few years ago a flux-coredwirewas usedwith CO 2 . “But we had to use heated regulators, whichwas a real hassle. When 100%CO 2 exits the gas cylinder, it starts to freeze up the regulator sowe had to use heated versions that required mains power. We found this to be a real nuisance,” he explains. “The introduction of Arcal Force instead of CO 2 has enabled us to bring the flux-cored process back into the workshop, with much better results and simpler technology.” Along with the fabrication of four of these leach vessels, there is a substantial amount of structural steelwork required to upgrade the mine’s capacity. “We work together with CIS, a sister com- pany that is fabricating the structural sections: cutting, drilling and preparing beams and welding on the end plates, for example,” Huisamen reveals. Where possible, he says that the semi-automatic MIG/MAG process with solid wire is preferred for down-hand welding of structural sections, “but we still use stick welding consumables, which clients often specify”. Solid wire processes can be excep- tionally clean, he says. The consumable wire is inexpensive and the welding speeds are excellent. “For out of position welding, client permitting, we now pre- fer to use the flux-cored process and, if

One of four giant uranium leach vessels being manufactured at Turnmill Engineering for use by a mine in Rustenberg.

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SAIW Member profile: Turnmill Engineering

A 3.0 m can for the Mwadingusha pump storage refurbishment project being prepared for submerged arc welding.

The steam drum for the SO 2 ready for shipping to site.

converter project completed and

for both the welds and the corrosion resistant epoxy paint specification,” Huisamen explains. “We have a 100%UT requirement for all the welds and for plate laminations – and if any indications are detected, then radiographic testing is required on the entire weld seam. We also have to meet hardness requirements and to performmagnetic testing on final welds and on the end bevel preparations, for which we have never seen a flaw,” he informs us. In addition, very strict visual testing requirements have to bemet. “Capweld heights cannot exceed 2.0 mm, with no undercut whatsoever. With respect to beadprofiles, the bead toplate entrance angle can’t be sharper than 160°. None of this canbe achievedwithout excellent fit-up and very careful attention by our welders and our sandblasting and paint technicians,” he says. With respect to higher complexity fabrication, Turnmill Engineering is cur- rently completing the delivery of a giant SO 2 converter and several peripheral components for an SO 2 abatement plant for a Polokwane smelter. The plant will use wet gas sulphuric acid technology to remove SO 2 from the furnace off-gas to comply with benchmark emissions standards. “As well as the converter itself, we are fabricating the steam drum, a spray cooler in 100% 316 stainless steel and the acid storage tank, which is mostly made in carbon steel – which is suitable because of the very high (over 98%) acid concentration – with some exotics used on the nozzles and other critical areas.

“The converter itself is being manu- factured in sixmodules, due to transport limitations, and consists of several different materials: carbon steel 516 Grade 70 boiler plate for the base and top section, 304 L stainless steel for the mid-top section and for the high-tem- perature centre, creep resistant 16Mo3 and SA204 Grade B plate is specified,” Huisamen says. The converter stands 40 m high and has a 7.5mdiameter. Internally, catalytic converter beds, heat exchangers anddif- fusers are used to efficiently convert the SO 2 offgas into SO 3 , which then has to be cooled, reactedwithH 2 Oand condensed intoconcentratedsulphuricacid (H 2 SO 4 ). “The technology is from Haldor Topsoe in Denmark, a global leader in catalysis and process technology – and the SO 2 converter unit will be the largest ever built,” he adds. Citing thewelding of the steamdrum for this project, Huisamen says that this very thick section pressure vessel had to beweldedusingmostly stick electrodes. “When the welding was independently inspected, the inspector sentmeaphoto saying he had never seen such beautiful stick welding,” he notes. “We rely on old-school welding prac- tices here. We have a collection of 30 or so extraordinary welders and skilled operators who produce incredible qual- ity. It is tough for new welders to join our team, because we cannot tolerate any inattentiveness at all. But for those that survive the first few weeks with us, they have access to one of the best sup- port teams in the country,” Huisamen concludes.

not permitted, we have to turn to sticks.” Also currently in the workshop is a significant piping contract for the Mwadingusha pump storage refur- bishment project in the DRC. Three of the six turbine-generators are being modernised at the hydropower plant to increase generation capacity. “We have set up a mass production style setup to manufacture the three feed pipes linking the reservoir at the top to turbines at the bottom. These 70 m long and 2.5 m diameter pipes are called penstocks andwe are required to fabricate and deliver a total of 48 twelve metre sections ready for weld assembly onsite,” Huisamen explains. “Starting with 12 mm flat plate, we first roll 3.0 m cans before inserting a seam joint, starting from the inside at ground level with a solidwireGMAWroot pass onto a backing plate. This is fol- lowed by a GMAW hot pass and we then fill the inside seam using a submerged arc welding setup on a boommanipula- tor. The can is then rotated to give access to the seam at the top. We backgrind the root and then cap the outside of the seamwith a final submerged arc bead.” By the time the contract is com- pleted, 192 of these cans will have been fabricated. “We join four of these cans together to give us the 12 m delivery length for shipping to site,” Huisamen tells African Fusion . While not particularly complicated in terms of fabrication, there are some complex requirements that have to be met. “The specification is very strict with respect towelding quality and non- destructive examination requirements,

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Cover story: voestalpine Böhler Welding

Specialised welding consumables for the sugar industry

UTP Maintenance, the voestalpine repair welding specialist, is a reliable supplier of welding consumables used for the repair and arcing of cane crushing rollers used in the sugar industry. Kenneth Labuschagne of voestalpine BöhlerWelding presents the company’s purpose designed offering for the better protection of these rollers and production optimisation in the industry.

E xtracting the juice from sugar cane to make sugar involves squeezing shredded cane be- tween large rotating rollers. Grooves in the cast iron roller surfaces and sub- sequently deposited globules of hard and highly durable metal improve juice extraction and prevent slippage of the shredded cane during crushing. Sugar cane is acidic with a pH of around 5 and carries up to 5%soil which is harvested with the cane. As a result, the mill rolls are exposed to a combina- tion of abrasive and corrosive wear and require periodic hardfacing to repair them. The hardfacing alloymust provide goodwear characteristics andadd to the good gripon the sugar cane andbagasse (the fibrous by-product) provided by the roller profile. A full sugar crushing roller overhaul involves a four-step rebuilding proce- dure, for which UTP Maintenance has developed a set of three dedicated hard surfacing coredwires andprocedures for mechanised welding.

In Step 1, the laterals, are deposited to strengthen and protect the sides of the teeth against abrasion. This is done using 1.2 mm diameter UTP AF DUR 600-MP wire, which is a cored wire that provides a hard impact resistant weld overlay. The same wire in 1.6 mm diameter is used in Step 2 to seal the top of the teeth and provide a firm base for the next step. In Step 3, the hook, which is also referred to as ‘picote’ is deposited with 1.6 mm diameter UTP AF 715 Hook flux- cored wire, which gives a weld metal with resistance to very high abrasion. Thesehooks on the teeth catch the sugar cane and bagasse and largely determine the output of a sugar mill in terms of tonnage of sugar cane juice and bagasse produced. Step 4 involves ‘arcing’ with a 2.8mm UTP AF Vanadium500wire. This special, large diameter cored wire operates in the spray arc mode at relatively low currents depositing high amounts of weld metal droplets of a uniform size.

It is used with a relatively long stick-out lengthandproduces a very powerful arc, which also enables the welding of the rolls in the presence of large quantities of juice and bagasse, while in operation during the harvesting season. “The use of UTP cored wires makes the whole repair procedure much more efficient, helping the mill to get a good extraction index. Deposition rates and duty cycles are much higher than procedures using stick electrode weld- ing. When compared to mechanised welding with solid wires, repair times can also be significantly shorter,” notes Labuschagne.

SBR and UTP: A successful partnership

S. B. Reshellers Pvt. Ltd. (SBR), located in Kolhapur in the Indian state of Maha- rashtra, is a specialist in the manufac- ture, reshelling and hardfacing of rollers used in the sugar industry. The company,

For the sugar industry, UTP Maintenance ensures an optimum combination of protection and productivity with innovative and tailor-made welding consumables and solutions.

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Function

Photo

Consumable and typical welding parameters

UTP AF DUR 600-MP: 1.2 mm Position: Vertical-down Current: 150-170 A Voltage: 25-28 V Stickout length: 18 V Travel speed: 36 cm/min Weaving width: 12-20 mm Number of torches: 1 or 2 UTP AF DUR 600-MP: 1.6 mm Position: Downhand Current: 160-220 A Voltage: 25-28 V Stickout length: 20 mm Travel speed: 64 cm/min Weaving width: 0 Number of torches: 1 or 2 UTP AF 715 Hook: 1.6 mm Position: Downhand Current: 180-230 A Voltage: 27-29 V Stickout length: 20 mm Travel speed: 54 cm/min UTP AF VANADIUM 500: 2.8 mm Position: Vertical down Current: 250-350 A Voltage: 28-36 V Stickout length: 40-60 mm Weaving width: 0 mm Number of torches: 1

Lateral Strengthen and protect the sides of the teeth. Provide a wider platform for Step 2, the base weld.

Step 1

Base Sealing top of the teeth. Preparing a platform for the hook weld.

Step 2

Hook Protection of top of teeth. Providing a firm grip on the bagasse. Higher crushing efficiency.

Step 3

Arcing Further improving grip on the bagasse. Protection of teeth profiles. Enabling repair while crushing.

Travel speed: 4-6 rpm Weaving width: 0 mm Number of torches: 1 or 2

Step 4

A full sugar crushing roller overhaul involves a four-step rebuilding procedure, for which UTP Maintenance has developed a set of three dedicated hard surfacing cored wires. See sugar consumable table at: www.voestalpine.com/welding/Industries/Sugar-Ethanol#!industry-tables#!industry-table- section-id-6983=paging:number=50|paging-6983-1:currentPage=0 table.

which is the largest of its type in India, caters to all major sugar factories and original equipment manufacturers of sugar mills in both the domestic and international markets. Hardfacing of roller shells, otherwise known as roller arcing, is carried out using hardfacing welding rods that are used to build up the tips and flanks of the roller grooves. Special flux- and metal-cored wire is used to generate extremely hard metal beads along the teethprofile. UTPMaintenance has been the preferred supplier of the specialised welding material used for arcing at SBR since December 2010. In cooperation with Fronius India, a new automatic welding system was introduced at SBR’s Kolhapur workshop for the arcing of sugarmill rollers. In a se- ries of trials conducted using UTP Vana- dium500 andUTPVanadiumSGwelding wire from voestalpine Böhler Welding, the results showed that this material was highly suited for the new welding system and fully met the requirements for achieving excellent arcing results at accelerated deposition rates. Tailor-Made-Protectivity UTP Maintenance ensures an optimum combination of protection and produc-

Diagram showing the positions of the lateral, base, hook, and arcing weld deposits.

UTP Maintenance has been pres- ent in the sugar and ethanol industry since the 70s through the development of products that have met increasing technical demands and productivity of plants. Over the years, UTPMaintenance has acquired considerable knowledge in the production and supply of welding consumables tailor-made to industry needs. “Weprovidebest inclassproducts formaintenanceand repair, claddingand metallisation; includingalloysof complex carbides and with specific hardness that fulfil the requirements of most different types of wear in this industry segment,” Labuschagne concludes.

tivity with innovative and tailor-made solutions. Everything revolves around the customer and its individual require- ments. That is expressed in the central performance promise: Tailor-Made Protectivity™. “Our range of flux- and metal-cored wires for the rebuilding of worn sugar cane crusher rolls continues this tradi- tion. Developed in close co-operation with specialised repair companies and mill maintenance departments, they feature welding characteristics that are fully dedicated to the rebuilding and protection of crusher rolls,” adds Labuschagne.

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Quality is safety paper: Louise Petrick

Quality is safety

In this paper from the Bali IIW International Conference of 2018, Louise Petrick of Weld Australia draws from some catastrophic weld failures to show how ethics, weld quality management and engineering interact to ensureweld safety.

W elding alters the engineered properties of a material, affect- ing irrevocable changes to the metallurgical structure and mechanical characteristics due to the addition of en- ergy to combine two materials into one. As a fabrication process, this method has been used since the early part of the 20 th century andhas become thebasicmeans to construct and build most of the industries required for modern society. Almost since the beginning in the 1930s, there was the recognition that welding codes or standardswere required for higher quality weld metal. This understanding has expanded to include and manage the parent material changes in the heat- affected zone (HAZ) aswell. Most codes and standards in use, have been influenced by catastrophic failures and therefore provide minimumrequirements to achieve suitable welds that will result in safe service. In addition, the control of weld proper- ties and therefore the integrity of a welded component to function safely, is managed in part by quality control. Weld safety, how- ever, is more than this, and should entail the whole process from design to delivery and is achieved by a systematic weld qual- ity management system, implemented ethically. This paper reviews the influence of some catastrophic weld failures, and aims to show how ethics, weld quality management, and engineering interact to ensure weld safety. Introduction Welding is defined in many places and in the Australian Standards it is described as a ‘joint in material produced by means of heat or pressure or both, in such away that there is continuity in the nature of themetal between these parts’. [1]. It encompasses a range of processes developed over the last century that have been commercially used since the early 1900s [2]. While its usefulness and versatility has been the foundation for many technologi- cal advances, the application of pressure or heat to achieve coalescence changes the engineered structure of the parent materi- als. Therefore, it may be a high risk process that requires careful management, since it

can affect the safety of the component or structure it is applied to. When selecting the appropriate weld quality management re- quirements, the application requirements determine the design code or standard, which sets materials, fabrication and inspection specifics to economically and safely deliver the required technology or product. The role of the engineer is to respond to a perceived need by building or creat- ing something to a set of guidelines – the relevant design code or standard – that performs a certain function [3]. It is impera- tive that the device, system, or component should perform its functionwithout failure. However, since everything must even- tually fail in some way, this means that a desired level of performance is needed. Therefore, it is the responsibility of the engineer todesign in such away as to avoid catastrophic failure that could result in the loss of property, damage to the environ- ment and injury or loss of life [3]. A traditional design methodology is shown in Figure 1. Here, the design usually provides in- put about dimensions and materials, but seldom to the fabrication and inspection requirements that will satisfy the applica- tion, the welding process, for example. When referring to a standard or code, the reference is mostly general and many aspects are left to the fabrication and inspection function to make engineering decisions. This may lead to decisions be- ing made during fabrication and inspec- tion that ultimately affect the sought level of performance of the components or structures, which, as some of the case studies presented will show, have resulted in catastrophic failure. Analyses done on catastrophic failures have identified fac- tors, flaws and failures in engineering that resulted in these events [3]. While the design and, therefore, en- gineering practices have fundamental influences on the safety and performance of components and structures, during fabrication the safe application of welding relies heavily on many disciplines, includ- ing welding inspection. The role of the welding inspector is also

Figure 1: Common conceptual model from design to product [5]. examined here and illustrated by looking at the consequences of poor inspection ethics and the importance of accurate inspection data. This article aims to show how an inte- grated weld quality management process is required to prevent catastrophic failures and achieve safe welds, from design to inspection during fabrication, as well as in-service inspection during maintenance activities. Quality management Why quality management is required for welding The old expression: ‘Horses for courses’ has been used to describe the fact that not all welding operations require the same level of intervention or management to achieve a safe outcome [13]. There are significantly different requirements for a basic weld to hold a small bracket in place to the com- plex requirements of a system under high temperature and pressure, where the cata- strophic failure of the weld could allow the uncontrolled release of energy, ie, an explo- sion. Sincewelding fundamentally changes the carefully engineered properties of the material when it is welded, the application determines the safety level needed, which will determine the applicable risk reduc- tion to be implemented that therefore influences the quality requirements, as shown in Figure 2. And many times at this part of the discussion, the question of cost is raised, very often in terms of the cost of implementing quality management. But the pertinent discussion should not just be about the cost of quality manage- ment, but rather the cost of catastrophic

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human factors include both ethical failure and accidents, and this study included unethical practices under design flaws, thereby concluding that engineering ethics was found to be one of the root causes of engineering disasters that resulted in catastrophic failure. Therefore, it was proposed that engineers as professionals have a responsibility to clients, employers and the general public to perform their duties inas conscientious aman- ner as possible. This goes beyond just actingwithin thebounds of the law[3], and requires avoiding conflicts of interest, not misrep- resenting knowledge and accepting work outside their area of expertise, while acting in the best interest of society and fulfilling the terms of the contract in a professional manner. In light of this, it is proposed that ethical engineering practice to prevent failure can alsobe extended, not just to fab- rication, but to welding inspection as well. In 2009, a welding inspector at Northrop Grumman’s Virginia shipyard in the USA reported a fellow inspector for signing off on ship welds without inspecting them [8]. The admission of wrong doing by the inspector resulted in a very serious situa- tion, since he was responsible for over 10 000 welds on eight Virginia class nuclear fast attack submarines and a new nuclear aircraft carrier. Itwas also found that 10%of the subma- rine welds affected joints on critical com- ponents and hull integrity. Equally alarm- ing was the inclusion of similar issues at General Dynamic Boat in 2010, at its Rhode Island shipyard, sub-building partner of Northrop Grumman. This highlighted that the failure of inspection ethics was not an isolated event, which precipitated a costly in-depth reviewandwelding re-inspection programme. While the Navy review of Dynamic Boat provided somemeasure of assurance, since it indicated that therewas a lowprobability of improper welds, the additional time and cost to validate safety critical welds added costs that were completely unnecessary. The question then is what can con- tribute to unethical welding inspection practices? Case study: Unethical welding inspection The importance of accurate weld inspection data It may be beneficial to conduct a formal in- dustry survey regardingwelding inspection

failure. This is the true cost benefit of analysis that is indispensable for the safe application of welding. Quality management historically But is qualitymanagement a newphenom- enon, amodern day buzz word, excessively used? The fact is that quality management has been around for centuries and can be traced back to the Middle Ages [4] where a master craftsman inspected work com- pleted by apprentices and journeyman before providing the finished products to clients. This ensured quality standards were met, that the finished products and all the required aspects were suitable for use; and it made certain that the client was satisfied. During the 1920s, quality management systems, as we know them today, started to emerge, where the focus still remained on the end product and quality control was determined by final inspections. This started to change in the 1940s, when companies continued to experience difficulties in following through with qual- ity standards, which precipitated a change with respect to inspections. These were now carried out by production personnel during the fabrication process at specific intervals, thereby preventing problems in theendproduct throughearlydetection [4], therefore the reduction in defective parts, resulting in cost savings and, possibly, in an increase in safety. Factors, flaws and failures contributing to catastrophic failure Catastrophic failure is definedby theCentre for Chemical Process Safety [6] as ‘A failure which is both sudden and causes termina- tionof one ormore fundamental functions’. According to the Oxford definition [7], catastrophic is defined as something that causes ‘sudden great damage or suffering’. So, it is a sudden failurewhere termination of one or more fundamental functions causes great damage or suffering. Since the aim of engineering is to prevent catastrophic failure when creat- ing new structures or components, or maintaining existing ones, it follows that there could be factors, flaws and failures contributing to the primary causes of engi- neering disasters [3]. These canbe grouped as human factors, design flaws, materials failures –whichwould includeweld failures – or extreme conditions and environments. Often, these occur in combination. Interestingly, as shown in Engineering Disasters and Learning from Failure [3],

Figure 2: How application determines quality requirements.

expectations, since numerous discussions within Australia with asset managers, fab- rication and maintenance companies and welding inspectors highlighted that there may be conflicting requirements affecting inspection practices. During some of these conversations, a ‘good’ welding inspec- tor was seen as someone not finding too many issues and therefore not interrupting production targets or project deadlines negatively. However, an industry survey done by TWI in 2011 onweld repair rates [9] showed that rates in the Power andOil andGas sec- tors were typically 1 to 3%, but with peaks up to 25% in specific locations with excep- tional values up to 55%. Peak repair rates were observed for root runs, fillet welds and areas with limited access. Both these sectors have piping systems, onshore pip- ing and pressure vessels, with the Oil and Gas sector including off-shore structures and pipelines. The factors affecting weld repair rates are shown in Figure 3. The main contributing factors affect- ing weld repair rates, listed in descending order, are: • Welder’s skills. • Poor or incorrect fit up. • Welding conditions, such as position and accessibility. • Fabrication or inspection requirements. • Thickness or number of runs. • Welding process. • Material grade. • Site welding conditions. • Inspection technique used. • Minor contributions (< 3% each) from production stage, project size or no specific factor identified. Therefore, professional welding inspectors acting ethically by fulfilling their responsi- bilities to their employers, clients and the general public can identify 93% of listed factors during the fabrication or mainte- nance welding activities. So the question then should be: “Do you want the welding

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