normalized rate of penetration

A brief description is given about the1990 edition of API B-type drill fluid standard Theconstrast with that of China ls also done for the ref-erence of spreading the standard works and evalua-tion of various treating agents.

对１９９０年版ＡＰＩ１３类钻井液标准的内容做了简要描述，同时与我国有关标准进行对比，对开展我国标准化工作，评价有关各类处理剂有一定的参考价值。