Skip to main content

Power Plant Maintenance: AEP Cardinal Station Unit 3 Cooling Tower

Brilliant, OH

Contractor: Cannon Sline Inc 

Project Scope

Inspect, repair and coat entire interior surface of cooling tower with dimensions 200 ft (61 m) in diameter and 424 ft (129.2 m) high.


  • A custom parapet clamp was required to work on sloped surface.
  • Custom design of a platform that could be pulled in using a change of direction sheave, allowing the platform to follow the wall slope.
  • A winch system and anchor plan was needed to use the change of direction sheave.
  • Design topside rigging system around existing lightning protection. 
  • Entire system had to be easy to use and relocate to keep to the 11 week outage schedule.


Spider designed and built a custom parapet clamp to work on a sloped parapet wall, a platform using a primary and secondary wire rope system with a horizontal lifeline running the length of the platform, and a winch system and sheave system that allow the platform to follow the sloped contour of the tower walls to give access to the underside of the slope.

The solution combined standard rental equipment with customized devices to reduce the overall cost of the project.

All design, manufacturing and delivery onsite was completed in five weeks.

Spider swing stage
Custom parapet clamps
AEP Cardinal Station Unit 3 Cooling Tower

Related Products

  • Custom Engineered Solution