DECONTAMINATION/DECOMMISSIONING TECHNIQUES PART TWO

Robotic Cleaning, Remote cleaning techniques, Tube Tech

Overview

Tube Tech takes the time to examine every aspect of every contract and find the best solution for each problem. Robotic cleaning systems include remote controlled dual-purpose, low-flow-pumps used with bespoke designed cleaning heads, remote extendable indexing arms and the unique WysperJet™ and Hydrowhip™ systems

The Challenge

  • The Fired Heater / Furnace constructed with finned
    l and bare convection tube banks
  • Cleaned alongside a ‘live’ furnace so access and heat had
    l to be overcome
  • Compacted hydrocarbon and refractory deposits combined with
    l friable scale coating the majority convection tubes and fins.
  • Thickness of deposit up to 5mm with some bridging between
    l tubes and fins
  • Increased fouling on lower banks having dropped from
    l upper sections.
  • Cleaning had to be cleaned quickly as plant needed
    l welding repairs before start up.

Our Solution

  • Access to furnace solved by use of cat ladders and
    l removing floor.
  • Mobilisation in under 10 days from enquiry,
    l robot modification, to start.
  • Robots required rapid re-configuration in order
    l to clean various convection bank designs.

Case Study

As the closures/decommissioning of older Nuclear Stations and Military Storage sites accelerates, there comes with it a greater need to find methods that are both safer and create less radioactive waste. Such was the case that confronted Tube Tech when approached by a UK nuclear plant to clean a host of surfaces and large selection of contaminated tube and pipe work. Other competitors had put forward systems that created secondary waste such as water and grit and the client asked if Tube Tech could offer a dry alternative.

After an exciting brain storming session with the client and a thorough site inspection Tube Tech put forward a selection of dry cleaning processes adapted from their extensive knowledge in solving many of the world’s most difficult cleaning challenges. The dry decontamination systems consisted of variable speed rotating, skiving heads with bespoke self-compensating, scraping and polishing cleaning heads. The above system was put to work cleaning 17 “Beam Pipes” and 34 CO2 Purge Pipes, the need was to remove as much paint and rust deposit from the pipe walls as possible thereby lowering radiation levels from LLW to free release. Once applied this system of bespoke cleaning heads was found to remove the deposits back to bare metal, and lowered radiation levels significantly quicker than expected by the client. Tube Tech also exceeded the clients expectations in its consistent monitoring, reporting and communication levels between its workforce and all those involved in the project.

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