An American petroleum company with two refineries on the West Coast of the United States embraced the concepts of condition monitoring early in its evolution. They saw measurable returns from the new approach. However, when they evaluated their maintenance activities and costs, they found they still had heavy expenditures, especially on their many pumps. They began to evaluate the incidence of failures and found that bearings or seals were failing in many of their pumps on an average of once every six months. The company then began to assess the causes of their high incidence of seal and bearing failure in pumps and found three general areas that required improvement: alignment, balance, and assembly.
The company addressed this problem by developing a new precision program with the full cooperation of upper management, operations, and maintenance, all of whom worked together to solve their machinery problems. By adopting precision standards for alignment, balance, and assembly, these refineries extended the mean time between failure from six months to more than six years.
The company in the preceding case history understood that the costs incurred by the excessive pump failures were more than those of just simple parts and labor. They also included the additional real costs of managers/supervisors and purchasing personnel’s time, of stocking and maintaining inventory, and of the planners who scheduled the maintenance. What was not recognized, however, was the further effect that machinery failure has on production and/or productivity. The actual impact on production can vary greatly depending on industry, process, and equipment. For example, in a refinery where there are redundant (backup) machines, a failure may have no effect on production. In the paper industry, however, there may only be one machine producing a particular type or grade of product. A failure may result in a complete halt in production. The cost savings resulting from precision maintenance practices in this case would be tremendous. The savings from reduced equipment downtime often far exceed the maintenance savings.