CAN/CSA-C50052-99 (R2016)

0 Introduction
1 Scope
2 Quality assurance
3 Definitions
4 Materials
   4.1 Selection of material
   4.2 Chemical analysis
5 Design
   5.1 General
   5.2 Corrosion allowance
   5.3 Design stresses
   5.4 Calculation methods
   5.5 Manholes and inspection openings
6 Manufacture and workmanship
   6.1 Manufacture
   6.2 Consultation between manufacturer and founder
   6.3 Foundry technique
   6.4 Geometry and dimensions
   6.5 Chemical composition and mechanical properties
   6.6 Workmanship
7 Repair of casting defects
   7.1 General
   7.2 Repair by welding
   7.3 Impregnation of castings
8 Heat treatment
   8.1 Heat treatment procedure
   8.2 Methods of heating
   8.3 Quenching
   8.4 Calibration of furnace temperature
   8.5 Heat treatment charts
9 Inspection, testing and certification
   9.1 Proof tests
   9.2 Inspection and routine tests
   9.3 Certification
10 Pressure relief devices
   10.1 General
   10.2 Bursting discs
   10.3 Self-closing pressure relief valves
   10.4 Non-self-closing pressure relief devices
Table
Figure
Annex
A Welder performance test

Applicable to cast aluminium alloy enclosures pressurized with dry air, inert gases, for example, sulphur hexafluoride, carbon tetrafluoride, or nitrogen or a mixtures of these gases, used in indoor or outdoor installations of high-voltage switchgear and control gear, where the gas is used principally for its dielectric and/or arc-quenching properties, with rated voltages: (a) 1 kV and up to and including 52 kV and with gas-filled compartments with design pressure greater than 3 bar (gauge); and (b) 72.5 kV and above.

Scope This Standard applies to cast aluminium alloy enclosures pressurized with dry air, inert gases, eg. sulphur hexafluoride, carbon tetrafluoride, or nitrogen or a mixture of such gases, used in indoor or outdoor installations of high-voltage switchgear and controlgear, where the gas is used principally for its di electric and/or arc-quenching properties, with rated voltages (1) 1 kV and up to and including 52 kV and with gas-filled compartments with design pressure greater than 3 bar (gauge); and (2) 72.5 kV and above. The enclosures comprise parts of electrical equipment not necessarily limited to the following examples: Circuit-breakers Switch-disconnectors Disconnectors Earthing switches Current transformers Voltage transformers Surge arresters Busbars and connections The scope also covers pressurized components such as the center chamber of live tank switchgear, gas-insulated current transformers, etc.