On May 26, 2016, a team of engineers of CIAE granted license to independently developed vertical tunnel of cold source for China Advanced Research Reactor (CARR) after its regular inspection and examination.

 The vertical tunnel, which will be used in CARR, was manufactured by experiment factory of CIAE. It was made of nuclear-class 6061 aluminum alloy and consists of upper flange, vertical tube section and lower capped end. At the normal condition, the tunnel is at high-level vacuum and servers as thermal insulation blanket. At the accident condition, it will act as physical isolation and pressure-bearing boundary between reactor and cold source when there occurs deuterium explosion in reactor, thus playing an important role in securing the reactor.

 The team firstly listened to a brief delivered by the factory on manufacturing of the tunnel, and then inspected its specifications, size and records on processing, examining and testing according to related contract, technical requirements and design drawing. After the inspection, it accepted that the processing of the tunnel conformed to quality requirements, and all technical indicators met standards of design drawing, technical specifications and the contract.

 The qualification of the vertical tunnel will create sound conditions for installation of in-core systems with cold neutron source, and will provide stable cold neutron beams.