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Although universal joints are found throughout construction equipment (CE), the design has not been fundamentally changed in nearly 100 years - until now. CCTY Bearing is introducing an alternative u-joint for intermittent applications that is smoother and stronger than the conventional design.<p></p><p>Construction machinery is constantly running over long periods of time, commanding individual components to withstand intense usage environments. With that in mind, CCTY Bearing's engineers created a u-joint that streamlined the mechanics while continuing to transmit torque, but with lower operational resistance.</p><p>The final result is an eight component joint that utilises a square ball - the Square Ball Universal JointTM. In contrast to the nearly 100 parts found in conventional u-joints, the simplified construction requires just:&nbsp;</p><ul><li> One square ball</li><li> Two yokes</li><li> Two retaining pins</li><li> One seal and</li><li> Two seal clamps</li></ul><p> Three main benefits of the re-engineered universal joint for the construction industry include:<br /> <span style="font-weight: bold;">Longer life:</span> <span style="font-weight: bold;">Larger load zone eliminates fretting:</span> Universal joints with needle bearings are subject to line load fretting on raceways from continued machine vibration as equipment runs for hours at a time. This fretting reduces the expected service life. The Square Ball Universal JointTM has a larger load zone than the combined line contact area of needle bearings. This larger load zone withstands vibrating applications by spreading the same surface pressure over a larger area.<br /> <span style="font-weight: bold;">Constancy:</span> Low starting and operational torque resistance: Starting rotational torque ranges from 0 to 0.025 NM when the operating angle range is 0 to 25o. Since the square ball universal joint contains just three moving parts, the starting torque is consistent.<br /> Needle bearing u-joints can have more than 100 parts per assembly. Tolerance stack-up issues with this number of components have inconsistent startup torque values from unit to unit.<br /> <span style="font-weight: bold;">Maintenance free: All moving components are lubricated for life:</span> A unique true seal covers all the moving parts, retains lubrication and keeps out containments. It never needs regreasing because the seal holds 20 times more grease volume than conventional universal joints, allowing a continuous coating on all moving components. It is important to note that the seal has an IP 86 rating.<br /> </p><p><span style="font-weight: bold;">Operational mechanics</span><br /> The square ball seeks its own centre between two yokes when it is rotating through an angle with some load. Rotational torque is concentrated around the left and right opposing zones of the yoke's ID to the adjacent cylindrical surfaces of the square ball central element, not the centre of the yoke or the grooves. </p><p>A common misconception about the design is that rotational force is placed on the pins. However, the pins simply keep the square ball in place, they do not transfer torque.</p><p>Constant velocity can be achieved when assembled with two properly phased and equal-angled joints, the same as a double Cardan CV. Field testing is underway at construction and agricultural OEMs with full-scale production scheduled for 2019.</p><p><br /></p>