Thorough purging of all four bearing seals on each universal joint can help alleviate the possibility of mixing incompatible greases. U-joint cross, broken at a bearing surface. U-joints seldom break off at the bearing surface. It takes a very large shock load to cause this type of failure. It is also very difficult to inspect for this type of failure because they, many times, start as a small crack and progress into a complete failure some time further âdown the roadâ.
A quantity called the slew rate, which is the rate of change of gradient amplitude is usually quoted in evaluating gradient performance and potential physiological effects (e.g. a maximum slew rate of 200 Tm-1s-1).
INFILTRATION RATE. The infiltration rate is the velocity or speed at which water enters into the soil. It is usually measured by the depth (in mm) of the water layer that can enter the soil in one hour. An infiltration rate of 15 mm/hour means that a water layer of 15 mm on the soil surface, will take one hour to infiltrate. In dry soil, water infiltrates rapidly. This is called the initial infiltration rate.