General requirements for pressure-retaining systems and components in CANDU nuclear power plants/Material Standards for reactor components for CANDU nuclear power plants

1.1
This Standard specifies the technical requirements for the design, procurement, fabrication, installation, modification, repair, replacement, testing, examination, and inspection of, and other work related to, pressure-retaining systems, components, and supports over the service life of a CANDU nuclear power plant.

1.2
This Standard applies to all pressure-retaining systems, including their components and supports, in a CANDU nuclear power plant.

1.3
This Standard applies to containment components, but does not apply to concrete containment structures.

1.4
This Standard does not apply to portable assemblies of pressurized items that are temporarily connected to a system or component to enable testing, venting, draining, calibration, or other maintenance activities, provided that they

(a) do not reduce the ability of a system to perform its design safety function;

(b) are under surveillance when connected and are removed upon completion of their function; and

(c) are constructed to Standards deemed by the licensee to be suitable for the application.

Note: Safety analysis, environmental qualification programs, or seismic qualification may be used to satisfy the conditions in this Clause.

1.5
In this Standard, "shall" is used to express a requirement, i.e., a provision that the user is obliged to satisfy in order to comply with the standard; "should" is used to express a recommendation or that which is advised but not required; and "may" is used to express an option or that which is permissible within the limits of the standard.

Notes accompanying clauses do not include requirements or alternative requirements; the purpose of a note accompanying a clause is to separate from the text explanatory or informative material.

Notes to tables and figures are considered part of the table or figure and may be written as requirements.

Annexes are designated normative (mandatory) or informative (nonmandatory) to define their application.

1.6
The values given in SI units are the units of record for the purposes of this Standard. The values given in parentheses are for information and comparison only.

N285.6.1 - Pressure tubes for use in CANDU fuel channels
 

1 Scope

This Standard specifies requirements for the fabrication and properties of seamless zirconium-2.5wt % niobium (Zr-2.5Nb) alloy pressure tubes for use in fuel channels in CANDU reactors.

-------------------------------------------------------------------------------

N285.6.2 - Seamless zirconium alloy tubing for reactivity control units
 

Scope

This Standard specifies requirements for the fabrication and properties of seamless zirconium alloy tubing, Grades R60802 and R60804, with diameter to wall thickness ratios less than 80. This tubing is used for reactivity control units in CANDU reactors.

-------------------------------------------------------------------------------

N285.6.3 - Annealed seamless zirconium alloy tubing for liquid injection shutdown system (LISS) nozzles
 

Scope

This Standard specifies requirements for the fabrication and properties of seamless zirconium-tin alloy tubing, Grade R60802 or R60804, which is suitable for use in liquid injection shutdown system (LISS) nozzles located in the moderator water in the core of a CANDU reactor.

-------------------------------------------------------------------------------

N285.6.4 - Thin-walled, large-diameter zirconium alloy tubing
 

Scope

This Standard specifies requirements for the fabrication and properties of thin-walled, large-diameter tubing made from zirconium-tin alloys, Grade R60802 or R60804.

Notes:

(1) Thin-walled, large diameter tubing has a diameter to wall thickness ratio greater than 50.

(2) This tubing can be used as calandria tubes and as tubes for reactivity control units in a CANDU reactor, and may be processed in the seamless or seam-welded condition.

-------------------------------------------------------------------------------

N285.6.6 - Non-destructive examination criteria for zirconium alloys
 

Scope

1.1
This Standard specifies requirements for non-destructive examinations (NDEs) of zirconium alloy components during manufacturing. NDE methods include visual, radiographic, liquid-penetrant, ultrasonic, and eddy current techniques.

1.2
Other standards may be used for the NDE of zirconium alloys, provided that they satisfy the requirements of this Standard.

------------------------------------------------------------------------------

N285.6.7 - Zirconium alloy design data
 

Scope

This Standard specifies the physical and mechanical property data to be used in the design of the zirconium alloy components specified in the CSA N285.6 Series.

-------------------------------------------------------------------------------

N285.6.8 - Martensitic stainless steel for fuel-channel end fittings
 

Scope

1.1
This Standard specifies requirements for martensitic stainless steel forged blanks for the fuel-channel end fittings of a CANDU reactor.

-------------------------------------------------------------------------------

N285.6.9 - Materials for supports for pressure-retaining items
 

Scope

This Standard specifies requirements for material for the support of pressure-retaining items in CANDU nuclear power plants. The materials covered in this Standard are in addition to the materials permitted by the ASME Boiler and Pressure Vessel Code (BPVC), Section III, Division 1, NF-2000, and Code Cases.

-------------------------------------------------------------------------------

N285.6.10 - Nickel-based alloy wire for fuel-channel spacers
 

Scope

This Standard specifies requirements for the nickel-based alloy (UNS N07750) wire used to form spacers for use between the pressure tubes and calandria tubes in the fuel channels in a CANDU reactor.

-------------------------------------------------------------------------------

N285.6.11- Zirconium alloy wire
 

Scope

This Standard specifies requirements for wires made from zirconium-tin alloy, Grade R60802 or R60804, used in the welding of zirconium components and in the manufacture of the spacers that are installed between pressure tubes and calandria tubes in the fuel channels in a CANDU reactor.