Nuclear Reactor Plants with a PWR (Pressurized Water Reactor) periodically require the removal of the top and bottom steam generator manway covers for internal access. In the past, this required the use of hydraulic torque wrenches, a manual method, or a one-piece system that was so heavy it required rigging to lift it up and down. The old methods took a lot of time in a hot, high dose rate environment or they were not convenient because they required special rigging and did not allow for the adjustment of single bolts.
Bolttech Mannings developed a much faster and simpler way to remove the top and bottom steam generator manway covers, while reducing the dose rate, using the ALARA principle, and taking FME compliance into consideration. This solution is one of a kind and the first of its type in the nuclear industry.
The system was designed as a four-piece quadrant system with individual ports that allow 16 bolts to be tensioned at the same time. It also allows bolts to be tensioned individually without removing the entire ring. Each quadrant is light weight at 60 pounds each with integral internal and external lifting handles, allowing a single technician to lift each segment up and place it without the assistance of rigging. All hoses are screwed directly into the manifold resulting in fewer oil leaks.
- Custom, made-to-order multi-stud tensioning ring system for proper operation
- Four-piece quadrant system with individual ports resulting in a simultaneously-tensioning system allows the tensioning of a single bolt or up to 16 bolts at a time
- Each quadrant has integral internal & external lifting handles for easy removal and placement
- 60 pounds per segment for easy installation
- Strategic Internal hose placement with 90 degree quick disconnects for easy operation
- Ability to isolate tensioning of individual studs
- Each 12-point socket has a line engraved on the outer ring for easy nut alignment during installation
- 16-port, 360 degree custom-designed hose manifold system directs flow of oil
- All hoses are screwed directly into the manifold to reduce oil leaks
- Ability to isolate each individual tensioner for singular load without removing any segments
- Minimal quick disconnects to reduce oil leaks
- ½” minimum stroke length
- Instructions are engraved on the top of the puller nut to ensure proper use
- Storage container with individualized compartments for easy storage
- Red internal warning line to alert technician of potential over stroke
- Custom-designed torque wrench to torque all nuts 20-50 ft lbs to seat them all the same
- 199,577 lb load capacity
- 25,000 PSI high flow pneumatic hydraulic pumping system with joy stick control
- Hydraulic hoses have a working pressure of 26,100 PSI
- 12-point sockets with built-in retention system (FME compliant)