Best practices: multi-ton component removal/replacement utilizing air casters.
This excerpt was originally presented to the ASME at POWER 2009 in Albuquerque, New Mexico. For more information or a to see the paper, visit www.asme.org and search for POWER2009-81184.
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.