The fuel channel of a CANDU reactor comprises two concentric tubes, a Calandria Tube (CT), and a Pressure Tube (PT), one inside the other. Each fuel channel is supported by the end shield lattice tubes through sliding bearings and by the annular spacers between the two tubes.

The annular spacers can move, and this could lead to contact between the pressure tube and the calandria tube, potentially leading to a pressure tube failure. The spacing is confirmed during inspections and adjustments are made to ensure safe reliable operation.

Additionally, hydrogen can build up within the zirconium alloys used in the pressure tubes and this can lead to changes in the alloy’s physical properties. Operators must keep a close eye on this build-up to ensure the safety of their asset and to satisfy the requirements of their regulators for continuous fit for service operation.

Our fuel channel inspection services are based around our Circumferential Wet Scrape Tool (CWEST*). We also support the legacy tool sets owned and operated by you including:

  • The Spacer Location And Repositioning tool (SLAR)
  • The Advanced Non-Destructive Examination tool (ANDE)
  • The Channel Inspection and Gauging Application for Reactors tool (CIGAR)
  • The Terminal Solid Solubility tool (TSS)

Our work on fuel channels is part of our comprehensive range of outage services that also include steam generator and feeder inspections, fuel integrity monitoring, and other bespoke inspections and maintenance activities.

*CWEST not available for sale outside of Canada until after November 30, 2027.

Why Us?

  • Familiarity with Tool Set

    We are the designer and original equipment manufacturer of many fuel channel tools and are well acquainted with the way they operate having deployed them on many campaigns. This familiarity allows us to work quickly, safely, and efficiently to produce results in which you and your regulator can be confident.

  • Rapid Response Capability

    Our permanently employed Power Workers Union and Society of Energy Professionals staff, allow us to mobilize quickly to deal with emergent issues. We identify the problem and establish and implement solutions, all in one smooth exercise, allowing you to focus on your other critical outage activities.

  • Outage Focused Approach

    A NASCAR-style front-of-house (Service Center) and Pit-Crew approach is used for our outage work. A front-of-house team handles the customer interface, organization, and documentation enabling the pit crew to focus on the equipment they service and maintain.

  • Safety First

    Safety is a core value for us. Our work is planned with safety in mind using all our specialists including those in radiation protection, conventional safety, and human performance. You can be sure we will work with you to deliver event-free outcomes.