Six 218 t Cat 793D trucks from Brazilian iron ore mining company CSN have gained a new life after undergoing a complete overhaul via a Cat Certified Rebuild. The work was made possible by Cat dealer Sotreq, from the conception of the project to the execution of the rebuilds, at its Vespasiano site near Belo Horizonte. For the mining company, renovating a high value-added asset represents an excellent cost-benefit ratio. The results with the reconstruction of the equipment are still being evaluated by the company, but the performance is already demonstrating the efficiency of the rebuild works carried out.
“It is possible to say that the Caterpillar Certified Rebuild is able to reestablish the equipment’s as new condition, thus allowing it to behave and perform as new again. Of course, it is necessary to wait a little longer to ensure everything that the project promises with regard to the reliability and performance of the fleet is achieved” says Ivan Antonio de Oliveira Junior, Manager of Maintenance and Engineering at CSN. The Caterpillar Certified Rebuild (CCR) was carried out at Sotreq’s Vespasiano unit, which has been completely reformulated and has five workshops.
It is a complete structure for renovations, recovery, tests and adjustments to serve customers in mining and other segments, following Sotreq & Caterpillar quality standards. In addition to the technical aspect of the equipment rebuild, the financial aspect is also taken into account by the company when opting for the rebuild. “In fact, the big point is the cost-benefit ratio, that is, this renovation allows us to have equipment with new features and performance but with a much lower investment. In addition, the big point that makes the project feasible is the extension of the asset’s useful life.
Rodrigo Amaral, Product Support Manager at Sotreq, confirms this cost-benefit advantage: “A CCR for large mining equipment, on average, costs 50% to 60% of the value of new equipment,” he says. He explains that the decision on the rebuild is taken jointly with the client, according to their needs. In the case of CSN’s trucks, he points out that several technical and financial studies were carried out, including TCO, which demonstrated the product’s viability. “The study phase also included visits by the client’s board of directors to Vespasiano, which attested to our ability to perform the service. Finally, the creation of a financing line for this service with Cat Financial was decisive for the conclusion of the deal.”
The rebuild process aims to return the equipment to a condition analogous to the new one. For this, the equipment needs to go through a robust reform process, where it is completely disassembled. The chassis goes through a general inspection process, crack recovery, joint machining, measurements and stress relief before reassembly begins. “This is the most critical step in the process and all the know-how from Sotreq and Caterpillar is applied to guarantee the structural longevity of the equipment. The Power Train and the other components are completely renovated in our Contagem CRC, following all the program’s criteria. In addition, items such as radiators, tanks, valve groups and cabin are repaired. At the end of the scope, more than 15,000 parts were replaced, including all hydraulic lines, electrical harnesses and sensors,” explains Amaral.
The refurbishment of the trucks lasted 120 days at the Sotreq facilities, an even more attractive period in relation to the delivery cycle of new equipment. The six rebuilt 793Ds were delivered between July and August 2020. Amaral points out that the strategy of carrying out a Caterpillar Certified Rebuild (CCR) in mining equipment allows the client to maximise the life of their asset for another lifecycle. This is because the equipment with a high hour meter loses performance and has a high operating cost, requiring a greater maintenance effort to continue operating at acceptable efficiency standards.
“Post-rebuild equipment returns to the similar hourly cost and performance of new equipment, reducing the asset’s TCO. Another benefit of the program is the reduction of HC on the site and the optimisation of other resources necessary to carry out major interventions, contributing to the maintenance routine of the equipment in operation on the site.” Sotreq offers several options for equipment rebuilds. In addition to the CCR carried out on CSN equipment, the Mining Machinery Reform Workshop has the option of CPT (Certified Power Train Rebuild) and a Rebuild in Material Time. “In this last option, the customer has total flexibility to define the scope of the partial rebuild within their financial needs, with the support of our technicians who bring information from inspections and essential tests to identify the critical points of the equipment to be prioritised,” concludes Amaral.