甘肃省庆阳市正宁县南部的核桃峪煤矿副立井冻结深度955m,为目前井筒冻结深度世界之最,同时该井筒还是一个事故井,冻结方案设计难度很大.对该井冻结方案的特点、难点与要解决的问题与博尔比钾盐矿进行了对比和探讨,针对该工程的难点提出了以大管径(Ф168mm)冻结管为代表的三大一小设计对策,以及采用同心双供液管和温控孔控制冻结壁发展等新技术解决了设计中的难题.取得了良好的效果,为以后类似工程提供了经验. The freezing depth of the deputy shaft of the Walnut Valley coal mine in the south of Zhengning County, Qingyang City, Gansu Province, is 955m, which is the highest in the world at present, and the wellbore is still an accident well. The design of the freezing scheme is very difficult. The difficulties and the problems to be solved are compared with Boli potash mine. According to the difficulty of the project, three small and one small design countermeasures, such as freezing pipe with large pipe diameter (Ф168mm), as well as double- New technologies such as liquid pipe and temperature control holes to control the development of frozen walls solved the design challenges and achieved good results, providing experience for similar projects in the future.