African Fusion talks to Dhurusha Chetty and Elbert Cilliers of Babcock Africa’s engineering business about the company’s ISO 3834-driven approach to meeting the critical fabrication and asset management needs of South Africa’s critical power and industrial infrastructure.
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Babcock specialises in high-integrity welding that often needs to be done in confined spaces.
Dhurusha Chetty, the Welding Engineering manager at Babcock and the responsible Welding Coordinator for several Babcock ISO 3834 accredited fabrication and onsite maintenance facilities, is one of few South African women to have chosen Welding Engineering as a career. “I hold the position of welding engineering manager at Babcock, where I also serve as the company-wide ISO 3834 Responsible Welding Coordinator,” she tells African Fusion.
Having graduated as a mechanical engineer from UKZN in Durban, Chetty started work as a trainee for Transnet Port Terminals before transitioning to Transnet Engineering. “My introduction to welding came when I took on the role of a responsible welding engineer involved in implementing EN 15085, the ISO standard governing welded railway vehicles. I was responsible for overseeing all welding-related tasks in the local production of underframes, bogies and other components for Bombardier and CNR locomotives," she explains.
Having been introduced to the world of welding and working beside international welding engineers to come up with ideas and solve production related challenges, Chetty decided to pursue a career in welding. “Subsequently, I pursued an Honours programme at the University of Pretoria and obtained certification as an International Welding Engineer (IWE) through the SAIW. Following that, I furthered my education with an MSc degree at Wits, with a specific emphasis on welding metallurgy,” she relates, adding that she joined Babcock to assume the responsibility for the company’s ISO 3834-2 certification in July 2023.
“Ensuring the highest standards of welding quality is a top priority for us, and ISO 3834 plays a crucial role in maintaining these standards consistently. Whether it is the welded fabrication within our workshops or providing on-site support for power stations and other industrial sites, every welding procedure and related activity revolves around ISO 3834. We fully embrace ISO 3834, recognising it as an excellent means to deliver the quality, safety and longevity required for the critical plant systems we fabricate and maintain. Rather than avoiding it, we see ISO 3834 as an integral aspect of ensuring the excellence of our welding practices,” explains Chetty.
“And Babcock’s engineering business has been certified to ISO 3834 Part 2 since 2013,” Elbert Cilliers, Head of Engineering points out.
Continuing, Chetty says that, unlike generic standards such as ISO 9001, ISO 3834 ensures that welding “nitty-gritties” are properly controlled: such as material and consumable control and management; welding machine verification and control; welder qualifications; and traceability. “So, it's an integral part of our day-to-day work across our business,” she assures, adding that this applies in full, albeit with some small variations, for both inhouse new fabrication work as well as onsite maintenance work during a shutdown project.
Babcock has responsible personnel available for several different certified sites. “At any given time, we hold five ISO 3834 certificates, tailored to the locations where we undertake welding-related contracts. In addition, we uphold certifications for all our own sites consistently and continuously,” she says.
On her choice as welding as a career, she says that it has always been about passion: “Whether you are male or female in the industry, it is about having a passion for what you do. For me, I found that within welding. I enjoy the job and the challenges that come with it. It is sometimes difficult being in an industry that is male dominated, but you can always face challenges by proving what you know. I sometimes need to work a little harder to prove myself, but at the end of the day the guys in the industry respect that.
“At Babcock, I have been welcomed by people who have been working here for years. The company is very accommodating: of various cultures and genders, which makes my job a lot easier,” she adds.
On the role of female welders in the industry, Chetty says there were several female welders working for Transnet on the fabrication of railway components. “There were notably skilled TIG welders among the team, but the challenging conditions in the power generation environment, especially on-site, can be uncomfortable, potentially deterring women from pursuing opportunities. It would be encouraging to see greater female involvement in this field, nonetheless,” she responds.
On the training side, Elbert Cilliers, Head of Engineering, says Babcock has a welder training and testing bay that is a mock-up of a typical tube bundle welders might find in a real steam boiler. “To train and qualify welders, we have a test rig where we mirror the complex boiler environments, particularly focusing on confined spaces and challenging positions where welders must work to complete their tasks. This approach effectively distinguishes high-quality welders from average ones, as we assign the most skilled welders to these demanding areas where repair needs may be frequent. During shutdowns, we strategically rotate welders based on their performance to ensure we meet the highest quality standards.”
Regarding current contracts, Cilliers notes that Babcock is actively involved in various projects within the power generation sector. These include projects such as high-integrity welding of auxiliary steam pipes, valve replacements, repairs to pulverized fuel burners, maintenance work on coal mills, which primarily involve structural welds. Additionally, we are engaged in the replacement of HP and IP turbine loop piping, which encompasses the pipes spanning from the emergency stop valve to the HP turbine inlet. The HP systems operate at around 170 bar and 540 ᵒC, underscoring the critical importance of producing high-quality welds. The potential consequences of a failure in these systems would be catastrophic,” he informs African Fusion.
Babcock is currently undertaking an upgrade on electrostatic precipitators at one of the power generation sites. This project involves a considerable amount of welding associated with structural steel and ducting. “We've consistently been involved in industrial projects as well. For instance, at sugar mills, we are currently performing crucial high-pressure welding on boilers. We often undertake boiler work and shutdown operations at sugar mills during their off-crop season,” he says, adding that Babcock also does boiler work in the power sector outside of South Africa.
In the pulp and paper industry, Babcock recently completed mainsteam piping welds, and for the petrochemical industry, the company has been busy since 2017 on a capital project to install new low NOx burners for emissions’ abatement. “That project includes a fair amount of welding associated with small bore piping systems,” adds Cilliers.
“Overall, we specialise in high-integrity welding, actively pursuing projects and maintenance contracts across various industries involving pressurised systems and boilers. This capability forms the cornerstone of our expertise. Babcock stands out as the only company in the nation to have successfully executed a complete Mainsteam system replacement on two power generation units, accomplishing this feat in record time. These projects demanded the highest calibre of engineering, quality, and welding proficiency, particularly in working with materials such as X20CrMoV11-1 and ASME A335 P91. Pressure vessels, a realm we have not actively engaged in, also present a viable opportunity for us. Our adaptable and transferable skills from our current work on boilers and piping make us well-equipped to deliver into this domain,” he notes.
On the process development side, Dhurusha Chetty says that Babcock is always on the lookout for more efficient and cost-effective welding solutions. The fabrication shop, for example, has now developed and internally approved a pipe welding procedure that uses Miller’s Regulated Metal Deposition (RMD) and Pro-Pulse welding machine to complete the root and the capping welds of piping joints, replacing the need for a TIG root pass and capping runs using stick electrodes. RMD is a type of modified short-circuit metal transfer welding process used in gas metal arc welding (GMAW). “Lincoln has also developed and improved on a similar technology with its PipeFab Power Source, and we hope to adopt these developments in the near future.
“Through initiatives such as these, we can offer an efficient and reliable procedure that is not only quicker and more cost-effective but also minimises waste in consumable usage. The utilisation of semi-automated processes is beneficial given the skill level available in the country. Achieving high-quality welds is more attainable with a welder using the semi-automatic GMAW process compared to the challenge of training them to produce welds of high integrity using a combination of TIG and stick welding,” Dhurusha Chetty concludes.
