Tavantolgoi–Gashuun Sukhait railway, Mongolia
The Tavantolgoi–Gashuunsukhait railway – approximately 240km long, with two stations and five passing loops – is set to be enormously significant for Mongolia’s economy. This new railway will allow Mongolia to increase its export capacity by 30 million tons of coking and thermal coal annually. As a result, the country’s mining companies will be able to compete in the global market for cheaper exports, supporting both coal exports and China’s ports.
To complete the Tavantolgoi–Gashuunsukhait railway project, Bodi Group (one of the largest business groups in Mongolia) and its subcontractor InCon were looking for a great value welding solution that was versatile and reliable. They turned to Pandrol for the solution and awarded the contract in early 2020, just before the onset of the pandemic.
Pandrol’s aluminothermic welding product was used for hard-to-reach places such as switches and crossings, stressing points and any remedial works. Versatility was key in these areas, which made Pandrol’s reliable, flexible aluminothermic welding product the perfect solution.
Under normal circumstances, a member of Pandrol’s specialist welding team would have travelled to Mongolia to carry out in-person training. However, border closures and travel restrictions made this impossible.
From July until September 2020, Pandrol supplied the aluminothermic welding kits and conducted the online training. With the High Flow Preheater (HFP) not ready for use at this time, Pandrol employed a traditional oxy propane preheating method, training the teams in Mongolia to use it correctly. This was a challenging phase of the project due to the equipment’s sensitive nature and the team’s lack of experience in this area.
Fish plates are usually used to secure tracks in Mongolia and the team on-site hadn’t seen pre-heating or used welding techniques before. With Covid-19 preventing in-person training, Pandrol delivered bespoke, virtual training to seven railway workers in Mongolia. Supported by a translator, the trainees spent three weeks learning how to weld and how to use the Pandrol equipment, both in a training environment and in situ on track. Teaching how to use the oxy propane preheating equipment virtually proved particularly difficult – its large flame can be disconcerting for new welders, and its high temperature can induce nerves at first.
Following the training, each employee shipped a test weld to Pandrol’s headquarters in France for quality checks and certification. All welds passed the European inspection criteria however, some of the welds were showing signs of overheating due to the use and set up of the oxy propane equipment. Pandrol presented the results to the team in Mongolia, identified that the preheating process in place needed improvement, and discussed the best solution.
By now, Pandrol was launching the Electric 230V HFP (High Flow Preheater) – a universal preheating system that raises the temperature of the parent steel before welding. Fully automated for easier, more reliable operation, the ignition, timing and stop are automatic and require no manual interference or flame adjustment. Using propane rather than oxygen and propane mixed reduces costs and makes the equipment light and portable.
The team in Mongolia was instantly impressed with the product, recognising that it would put welders’ instantly at ease and remove safety risks. Almost a year after the contract was first signed, in March 2021, the HFPs were manufactured, shipped and delivered. The Pandrol team conducted HFP training, which resulted in an instant improvement in the welding quality. This was a fast, easy solution that empowered the Mongolian team to do the best possible job.
As Frédéric Delcroix, Pandrol’s Welding Technical Director, explains: “Our High Flow Preheater’s built-in timer increases accuracy – improving quality and reducing the defect rate of welds due to preheating, which can be a real problem for rail operators. By providing a uniform preheat between the head and bottom of the rail, the High Flow Preheater reduces stress in the weld. We’ve also made it easier to operate; there is no need to adjust the torch height, which saves time and as the system is fully automated, less training is required. It is straightforward for new welders to learn to operate and offers the added reassurance that comes from knowing the preheat has been even.”
Welding has continued successfully and rapid progress is being made on the Tavantolgoi–Gashuunsukhait railway. In 2021, more than 1,300 pieces of joint were welded on the main track. This year, the team is planning to weld 700 joints on the turnouts.
Using the HFP ensured completed welds were consistently better quality, more accurate and highly reliable. The solution was delivered purely to help the teams in Mongolia, offering peace of mind, confidence and assurance for welders without experience of oxy propane methods. The coaching we delivered allows track workers to preheat effectively with very little training.
As Chris McKeown, Head of Operations for Aluminothermic Welding & Equipment for Pandrol UK notes, this has been a successful project on multiple levels. “It just goes to show that when we’re faced with challenges, we can be agile – bringing innovative ways of working to the table to the benefit of client outcomes.”