Hydraulics & Pneumatics March 2022

HYDRAULICS 24 HYDRAULICS & PNEUMATICS March 2022 www.hpmag.co.uk VI improver molecules are sheared. So, does used Shell Tellus S4 VK retain its kinematic viscosity? Yes: Shell Tellus S4 VK 32 remains above the viscosity threshold even after use and its shear loss is lower than required by leading equipment manufacturers. This viscosity retention combined with advanced additives provides exceptional wear protection. Wear measured in the Vickers V104C (ISO 20763) and Denison double (T6H20C) pump tests was half the maximum allowed limits, and 58% lower than the Eaton 35VQ25 test limit. 2 Long fluid life Shell Tellus S4 VK has a wide operating temperature range, but, unlike conventional high-VI fluids, it also resists shearing for a long fluid life. For example, in the tough KRL shear test (DIN 51350- 6/CECL45-A-99), the kinetic viscosity loss at 100°C for the new product is just 8%, almost half of the 15% maximum industry limit. (Note that some fluid suppliers make strong shear stability claims based on less severe (sonic shear and other) tests.) 3 This strong shear resistance (also seen in the used oil viscosity profile in Figure 5) translates into long fluid life; by retaining the right viscosity even after use, the fluid helps to mitigate the need to change fluids to ensure high- and low- temperature wear protection of pumps and components. Overall cost benefit So, what do these benefits mean for an operator’s bottom line? Which is better, one all-season fluid or a two-fluid (summer and winter) choice? Although a high-performing, all-season, long-life fluid commands a premium, avoiding switching between summer and winter grades means that only half the fluid volume is needed, a significant contribution to sustainability efforts through reducing consumption and waste. In addition, avoiding fluid changeovers saves labour and downtime costs. Using Shell Tellus S4 VK, as demonstrated by the wear and other test results, also helps to reduce maintenance and parts costs by ensuring that components are always protected, including during unseasonable weather events when some operators may be caught out with the wrong grade. Simulated calculations demonstrate a potential overall maintenance saving associated with using Shell Tellus S4 VK of up to 10% compared with a two-fluid solution. 4 Footnotes 1 The statistics in this graphic are based on a survey, commissioned by Shell Lubricant Solutions and conducted by Edelman Intelligence, based on 350 interviews with construction sector staff who purchased, influenced the purchase of or used lubricants as part of their job across the USA, China, India, Germany, Russia, Indonesia and the UK from March to April 2018. 2 All measurements use industry standards. The actual effects and benefits may vary, and no guarantees are provided. 3 https://www.savantlab.com/testing- highlights/testing-shear-stability-and- viscosity-loss/ 4 The savings indicated are typical values obtained through laboratory testing and through field validation. They do not constitute any representation or guarantee that such savings will be achieved in any particular situation, as there are multiple variables that may affect performance. This calculator and its results should therefore not be relied on in choosing whether to purchase any Shell lubricants. www.shell.co.uk Fig. 5: Shell Tellus S4 VK fluid’s wide operating temperature range for new (solid line) and used (dotted line) fluid. Fig. 3: A single, high-VI fluid solution. Fig. 4: Viscosity improvers can be susceptible to shearing, which may compromise fluid life.