Best Practices: Multi-Ton Component Removal/Replacement Utilizing Air Casters

Power plants originally designed to be decommissioned at 20-30 years are extending their service life by removing/replacing major power plant components. This requirement is contrary to the original floor and workspace designs engineered for power plants. Feedwater heaters, casks, heat exchangers, and other very large (50’ +) and heavy (20-100 ton) components can overcome floor and space restrictions by using a combination of air casters and cranes. This proven methodology saves in excess of 75% the cost of a standard crane-only operation and significantly reduces the possibility of permanent floor damage. Air caster transport systems are low profile and easily insert under industrial heaters, exchangers, transformers, etc. The casters raise components and carry them across the floor, spreading the multi-ton weight across the surface area without damage to the floor or component. Air casters are frictionless even with the heaviest loads, and significantly reduce ergonomic risk while also providing the benefit of requiring a reduced workforce to move the component across the floor. Controlled drive systems allow a single operator to easily move components omnidirectionally without wheels or rails, and into position within .5 inches/13mm accuracy. Proven effective in existing nuclear plants as noted in the ICONE paper presented by Tokyo Power. Air casters, often coupled with cranes, significantly lower material handling costs associated with new installation and repair/refurbishment of components up to and over 5000 tons. Air casters operate on normal compressed air and have very few moving parts, resulting in low ongoing maintenance costs. INTRODUCTION Early prior research demonstrated the superiority of ceramics for bearings (1, 2) and the existence of elastohydrodynamic (ehd) lubricant films at ball and roller contacts (3), the calculation of which is now an accepted part of bearing engineering. These new concepts are now used in the design of lubrication systems with solid lubricants that operate in much more severe environments than oils and greases (4, 5). Proprietary computer codes and unique patented bearing configurations for optimizing the performance of bearing/solidlubricant systems have been developed (6, 7 and 8). In this way, patented self-contained solid-lubricated all-steel and hybrid-ceramic ball and roller bearings are now available for environments that do not contribute to their lubrication, such as in air or vacuum. NOMENCLATURE Put nomenclature here. Put body of the paper here. Put body of the paper here. Put body of the paper here. Put body of the paper here. Put body of the paper here. Put body of the paper here. Put body of the paper here. Put body of the paper here. Put body of the paper here. Put body of the paper here. Put body of the paper here. Put body of the paper here. ACKNOWLEDGMENTS Put acknowledgments here.