Description

The Absorber Rod Drive Mechanism (ARDM) Flask is a leak tight, shielded, inert atmosphere flask used for handling of control and safety rod drive mechanism, diverse safety rod drive mechanism, failed fuel localization mechanism and other slender assemblies.

The components transported may be contaminated by sodium residues from the primary sodium circuit, so it is essential for the flask to be leak tight, lead shielded and maintained under argon atmosphere, so that the contamination does not spread, and sodium to air/moisture exposure is prevented.

The system consists of:

• Flask body
• Air locks
• Lifting head
• Support structures
• Control panel

Construction details

Material: IS2062 & SS 304L

Dimensions: Height 22.5m ; Dia. 0.5m

Critical aspects

• HLT performed on ARDM flask stainless steel assemblies like DSRDM, CSRDM, FFLM by pressure hold method. HLT testing was successful at following parameters:
• Test Pressure: 1.1 kg/cm2
• Acceptance criteria for local leak rate: 1 X 10-7 mbar.lit/sec
• Acceptance criteria for global leak rate: 1 X 10-6 mbar.lit/sec
• Lead pouring was carried out for radiation shielding
• Full load test using dummy load of 5 tonnes was conducted