各水泥厂在试行水泥新标准中,普遍遇到的困难是抗拉强度不高,并有七天抗拉强度低于三天的倒缩现象。通过局属21个水泥厂半年多的实际工作,并在江南,启新两厂分别召开的两次座谈会,大家讨论研究的结果,认为抗拉强度不高主要是游离石灰起了破坏作用。根据各水泥厂实际经验和试验资料证明,只要是游离石灰增加,相反地抗拉强度必降低,这一反比关系,已不容怀疑。中国水泥厂的经验,当游离 The common difficulties encountered by cement plants in trials of new cement standards are the low tensile strength and seven days of shrinkage that is less than three days. Through the actual work of the bureau’s 21 cement plants for more than half a year and the two workshops held respectively in the Jiangnan and Qixin plants, the results of the discussion and discussion concluded that the lack of tensile strength is mainly due to the destruction of free lime. According to the actual experience and test data of cement plants, as long as free lime increases, the tensile strength on the contrary must decrease. This inverse relationship has no doubt. China cement plant experience when free