Can you dig it?

Despite significant challenges over the last few years that led to supply chain disruptions and varying demand, the construction industry is still growing. Rising levels of urbanization and associated infrastructure developments, along with increasing investment in public facilities such as schools and hospitals, means that the forecast for the sector is looking bright. 

By 2030, the global construction industry is estimated to expand by 4.5 trillion USD to 15.2 trillion USD, with growth concentrated in China, India, the US, and Indonesia.1 This rising requirement for buildings and infrastructure means rising demand for construction vehicles. 

A building site places unique challenges on construction equipment. Exposure to rain, sleet, and snow, mean working surfaces can quickly become quagmires. Deep ruts formed by heavy machinery fill with water, creating thick and viscous mud that clings to surfaces, working its way into gaps, such as around gearboxes and axles. In these locations, face seals commonly retain lubricating fluids within rotary systems, preventing external particles, such as mud, reaching sensitive components. 

As a vehicle moves around a site, mud can build up around face seals, packing against them and causing compressional stresses in the metal parts that form their bodies. As more mud accumulates, pressure increases, potentially cracking the metal and allowing external contaminants into the lubrication media. 

Dirt that makes its way into these fluids can act as an abrasive, rapidly causing damage and leading to system failure. Failures mean additional downtime and maintenance, which is highly undesirable due to the tight deadlines typical within the construction industry. 

“Seeing the issues with face seals related to mud build-up in the undercarriage of excavators, we knew that we could create a better solution,” says Nicolo Olivetti, Product Manager for face seals at Trelleborg. He has been helping his customers with engineering challenges like this from his office in Modena, Italy, for over 13 years. “The solution to mud build-up required innovative thinking; rather than direct resistance, it was about flexibility.” 

After in-house engineering teams had analyzed the application to determine the critical performance parameters, design constraints, and operating conditions, Nicolo’s team developed an entirely new solution. 

Nexus Face Seal was the result of the design process, which required re-consideration of both the application and possible solutions from the ground up, including the materials used and the geometry of the final product. 

“Part of solving the issue was the development of a new solution for Trelleborg’s portfolio. Instead of being rigid and brittle, the Nexus Face Seal is light and flexible,” says Nicolo. “By shaping two parts of the seal’s metal body and combining them with two custom-formed elastomer elements, we have created a light and flexible barrier to external contamination. This has improved life expectancy when compared to other face seals, at a better price point.” 

Testing backs up Nicolo’s claims. “Though it is impossible to see any leakage that might occur, it is possible to look for contamination in lubricating media; dirt or water is a sign that leakage has occurred,” explains Nicolo. 

Nexus Face Seal endured 600 grueling hours in laboratory experiments, running at speeds of one meter per second in the same aggressive and viscous mud encountered on a building site. “We tested the Nexus Face Seal and competitive products to the same standards and conditions, and on all counts, it exceeded their performance.” 

Now Nicolo and his team are testing many other slow-speed rotating applications, such as other vehicles operating in contaminated environments like tunnel boring machines, to see if Nexus Face Seal can reduce maintenance requirements there. “Due to the aggressiveness of external environments and the short service life of existing products, we believe Nexus Face Seal to be the right solution in these circumstances too,” expands Nicolo. 

An essential part of working with Trelleborg is the support its customers receive. “We are on-hand at the Nexus Face Seal Center of Expertise in Modena to assist with customizing and assessing applications, including quick sample production. Our manufacturing and logistics are capable of scaling up with our customers and providing the volumes they need,” concludes Nicolo.  

For more information, please visit: Seals