GIW Pump Design Improvements Boost Reliability
GIW said that before its engineers were tasked with the pump project, its team had familiarized themselves with the mine’s operations while assisting it in tackling issues with cyclone-feed pumps. In 2009, after years of dealing with poor performing mill pumps, resulting in a costly mill outage every 800 hours, mine management began looking for a solution that could help maintain a more reliable shutdown schedule, minimize expenses and meet a high safety standard.
“GIW responded to the customer’s appeal for help by custom designing an improved suction liner and impeller to be installed inside the existing competitor pump, providing improved hydraulics and wear life,” said Hernan Palavecino, GIW’s South American regional sales manager. “During the initial run of the new GIW technology, the customer was astonished to see an ‘almost new’ suction liner after first inspection at 1,300 continuous hours. Keep in mind that the customer was accustomed to failures at 800 hours with their old supplier.”
Later, following this improvement in performance, mine personnel noticed the presence of tramp balls in the process flow. Fearing a catastrophic failure, the mine again turned to GIW for a solution. In turn, GIW designed and built a complete jacketed casing in just two months to resolve the potential safety issue. The customer, impressed, decided to replace the installed other-brand pump with a complete GIW MDX-750, the world’s largest mill pump, which provided 2,000 hours of reliable wear life and reduced plant outages to just four per year.
Since then, GIW has successfully installed seven MDX-750 pumps in the plant. Once the lines were upgraded to GIW technology, the customer set yet another new target: to extend the operational cycle and reduce plant outages from four to two annually. To accomplish this goal, they would need cyclone feed pumps that could run 4,000 hours between shutdowns with no operational interruptions. Due to the size of the pumps and severity of the mining conditions, this was a huge undertaking, according to GIW—one that had never been accomplished in the industry. However, GIW experts put their knowledge of the customer’s systems and their advanced metallurgy to good use to find a solution.
GIW said it has long been dedicated to improving performance of its pumps in cyclone feed applications, with the main focus on use of advanced metallurgy and variable geometry for the wet end during operation. For instance, users now can alter the geometry of a GIW pump’s suction liner impeller interface while the pump is operating, using its adjustable suction liner technology.
Ultimately, GIW engineers developed a brand-new material technology called Endurasite, claimed to be capable of resisting the effects of abrasion for extended periods. When applied to the MDX-750 highwear, wet-end parts, this white iron alloy is said to vastly improve pump wear life and, in turn, extends time between shutdowns.
Creating this solution from scratch was a complex undertaking, and both GIW and the customer were aware of the potential pitfalls of testing a new material in an active mine. “This was not only difficult for the customer but a challenge for GIW as a supplier,” explained Palavecino. “Because this was an unprecedented project in the market, every extra hour of operation was a discovery and the risk of unexpected failure or shutdown was present every step of the way.
“We set a target of 4,500 hours for the first test cycle, but during the campaign, we saw that it was possible to extend the cycle over 5,000 hours without operational risk,” he said. GIW said it not only achieved the customer’s goal, but also managed to exceed it by cutting annual shutdowns in half and drastically improving the total cost of ownership with an estimated savings of $6 million per mill line. “Reaching this target is the result of several years of continuous improvements and focusing on the customer,” explained Palavecino. “It was achieved and exceeded because of the commitment and teamwork between the customer and supplier.”