球床式高温气冷堆示范工程球形燃料元件的研制

Research and Manufacture of Spherical Fuel Element for HTR-PM Demonstration Project

为满足球床式高温气冷堆(HTR-PM)示范工程对球形燃料元件大批量生产、单球高铀含量和低破损率的要求,必须对10MW高温气冷堆时期的球形燃料元件生产工艺进行改进和优化。通过对基体石墨粉、穿衣、压制、车削和热处理等关键设备及相关工艺进行重新设计和优化,建立了规模化的球形燃料元件生产工艺。采用该工艺生产的球形燃料元件,冷态性能如压碎强度、热导、磨损和腐蚀等均满足HTR-PM的技术指标,特别是球形燃料元件的平均自由铀含量与HTR-PM球形燃料元件的自由铀含量指标(6.0×10-5)相差近1个数量级。采用优化后的规模化生产工艺,成功地研制出符合HTR-PM技术要求的球形燃料元件。

In order to satisfy the requirements of mass production ,high uranium loading and low free uranium contents of spherical fuel element （SFE） for high temperature gas-cooled reactor pebble-bed module （HTR-PM ） demonstration project ,the manufacture process of SFE for 10 MW HTR should be modified and optimized .The new optimized SFE manufacture process was established through the modification and optimization of key equipment and relative processes such as matrix graphite powder , overcoating , moulding , lathing and heat treatment . T he un-irradiated properties such as crush strength ,thermal conductivity ,abrasive wear and oxidation corrosion of SFE manufac-tured by the new process meet all the design specifications of SFE for HTR-PM .In particular ,the mean free uranium contents of SFEs are nearly one order lower than the design specification （6.0 × 10 -5 ） of SFE for HTR-PM . The qualified SFEs forHTR-PM were successfully prepared with the optimized large-scale manufacture process of SFE .