HB0—39—67主要存在三个问题:一是图形不全,仅有一个外六方形,与实际使用情况不符;二是标题中“放扳手处”的词意不妥,含糊不清;三是表内公差数值采用最大、最小表示法,图中不易标注,也不清晰。修订组对上述三个问题,到有关工厂进行了调查了解,广泛征求意见,同时,还参考了有关国外标准,在此基础上对HBO—39—67进行了修订。修订后的标准编号为HBO—39—75。 HB0-39-67 there are three main problems: First, incomplete graphics, only one outside the hexagonal, and the actual use of the situation is not the second is the title of “put a wrench,” the word meaning inappropriate, ambiguous; third Tolerance values ​​within the table using the maximum, minimum representation, the picture is not easy to mark, nor clear. The revision team conducted an investigation on the above three issues, made inquiries about the factories concerned and solicited opinions extensively. At the same time, it revised the HBO-39-67 on the basis of the relevant foreign standards. The revised standard number is HBO-39-75.