The reactor internals of the HPR1000, China’s third-generation nuclear power technology, were fixed into position at Unit 2 of the Karachi nuclear power plant, in Pakistan, on Jan 28 –– 35 days ahead of schedule.

Reactor internals are the major structures within a reactor pressure vessel that have one or more functions such as supporting the core, maintaining fuel alignment, directing primary coolant flow, providing radiation shields for the reactor vessel, and guiding in-core instrumentation. 

As the core component of the reactor pressure vessel, the internal components of the reactor are all stainless steel structures manufactured and assembled to the highest of standards, according to CNNC.