国防技术的迅速发展往往迫使军事装备现代化,以使这些装备在其整个的技术使用时期中能充分发挥作用。而研制及生产费用的增加显然使得即使是大国也不可能总是用最新的武器装备它们的部队。因此日益普遍的做法是,仅仅是把武器系统的最陈旧的部件更新,而其余的部分尽可能使之现代化,并在一定条件下继续使用它。例如一百年来在考虑新的火炮时基本上使用了这种方法。一般来讲,坦克的技术使用期为25年,因为它是比较贵的武器系统,因而在各个时期,人们都努力使它在部队中使用的时间尽可能长一些。下交将阐述二次大战末期以来,在老坦 The rapid development of national defense technology tends to force the modernization of military equipment to make these devices fully functional throughout their technology use. The increase in research and production costs apparently makes it impossible for even large countries to always equip their units with the latest weapons. It is therefore an increasingly common practice to simply update the oldest parts of a weapon system while remaining parts modernize as much as possible and continue to use it under certain conditions. For example, this method was basically used when considering new artillery for a hundred years. In general, the tank has a useful life of 25 years because it is a relatively expensive weapon system, and as a result, people strive to keep their use in the army as long as possible for each period of time. The next hand will elaborate on the old Tan since the end of the Second World War