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).
Churn Rate. The rate at which customers terminate their relationships with a company over a given period of time. For example, if five customers in 50 discontinue their cable every month, the churn rate is 5%. The church rate contrasts with the growth rate, which, in this case, is defined as the number of new clients or customers. If a company is to grow, the growth rate must consistently exceed the churn rate.