The previous fixed equipment / pressure vessel engineer in my plant OK'd a 30 year waiver on the internal inspection of our API620, low pressure, double walled refrigerated tank. This is not a small tank: 23m diam, 24m high.
Construction is essentially CS outer shell. 9Ni inner shell. It stores Ethylene at -101C [or in that ball park] and has a perlite insulation filler between inner and outer shells. We have CP on the base.
The guidance notes he left referred to the potential for damage on inducing a temperature cycle for inspection.
A degradation review suggests that external issues are the main degradation concerns during normal service.
The 30yrs are up in 2009.
Any industry experience available to suggest a need for inspection??
(In Victoria Australia, we've moved to a self regulated regulatory audit at any time environment...)
Thanks in advance.
Rob
Construction is essentially CS outer shell. 9Ni inner shell. It stores Ethylene at -101C [or in that ball park] and has a perlite insulation filler between inner and outer shells. We have CP on the base.
The guidance notes he left referred to the potential for damage on inducing a temperature cycle for inspection.
A degradation review suggests that external issues are the main degradation concerns during normal service.
The 30yrs are up in 2009.
Any industry experience available to suggest a need for inspection??
(In Victoria Australia, we've moved to a self regulated regulatory audit at any time environment...)
Thanks in advance.
Rob
