英语翻译It is the minimum clearance space intended between matin

英语翻译
It is the minimum clearance space intended between mating parts and represents the condition of tightest permissible fit.If a shaft ,size 1.498,is to fit a hole of size 1.500,the minimum size hole is 1.500 and the maximum size shaft is 1.498 .Thus the allowance is 0.002 and the maximum clearance is 0.008 as based on the minimum shaft size and maximum hole dimension.
Tolerances may be either unilateral or bilateral.Unilateral tolerance means that any variation is made in only one direction from the nominal or basic dimension.Referring to the previous example,the hole is dimensioned 1.500,which represents a unilateral tolerance.If the dimensions were given as 1.500+0.003,the tolerance would be bilateral ；that is ,it would vary both over and under the nominal dimension.The unilateral system permits changing the tolerance while still retaining the same allowance or type of fit .With the bilateral system,this is not possible without also changing the nominal size dimension of one or both of the two mating parts.In mass production,where mating parts must be interchangeable , unilateral tolerance are customary .To have an interference or force it between mating parts. The tolerance must be such as to create a zero or negative allowance.
The drawing must be a true and complete statement of the designer’s requirements expressed in such a way that the part is convention to manufacture.Every dimension necessary to define the product must be stated once only and not repeated in different views .Dimensions relating to one particular feature,such as the position and size of a hole ,should ,where possible,appear on the same view.

It is the minimum clearance space intended between mating parts and represents the condition of tightest permissible fit.If a shaft ,size 1.498,is to fit a hole of size 1.500,the minimum size hole is 1.500 and the maximum size shaft is 1.498 .Thus the allowance is 0.002 and the maximum clearance is 0.008 as based on the minimum shaft size and maximum hole dimension.
这是配对零件之间所需的最小间隙,代表最紧密的容许配合条件.假设一个直径为1.498的轴,和一个为1.500的孔相匹配,孔的最小值为1.500而最大值为1.498.因此容差为0.002,根据轴的最小值和孔径的最大值可得最大间隙为0.008 .
Tolerances may be either unilateral or bilateral.Unilateral tolerance means that any variation is made in only one direction from the nominal or basic dimension.Referring to the previous example,the hole is dimensioned 1.500,which represents a unilateral tolerance.If the dimensions were given as 1.500+0.003,the tolerance would be bilateral ；that is ,it would vary both over and under the nominal dimension.The unilateral system permits changing the tolerance while still retaining the same allowance or type of fit .With the bilateral system,this is not possible without also changing the nominal size dimension of one or both of the two mating parts.In mass production,where mating parts must be interchangeable ,unilateral tolerance are customary .To have an interference or force it between mating parts.The tolerance must be such as to create a zero or negative allowance.
公差可以是单边公差或者双边公差.单边公差是指相对于名义尺寸或者是基准值的偏差只能在一个方向上.根据之前的例子,孔的尺寸是1.500,而其公差为单边公差.若该尺寸为1.500+0.003,则该公差为双边公差,即其实际值将在名义尺寸上下浮动.单边系统容许在保持相同的配合容差的同时改变公差.而在双边系统中,不改变两个匹配零件的一个或两个正常值的话是不可能的.在大批量生产中,配对零件互相通用,单边公差是最常见的.为了确保配对零件之间拥有或者强制接口,公差必须为零或负容差.
The drawing must be a true and complete statement of the designer’s requirements expressed in such a way that the part is convention to manufacture.Every dimension necessary to define the product must be stated once only and not repeated in different views .Dimensions relating to one particular feature,such as the position and size of a hole ,should ,where possible,appear on the same view.
图纸必须是设计者要求的真实而完整的陈述,按惯例描述零件是如何制造.每个定义零件所必备的尺寸必须只定义一次而不能在其他的视图中重复.对于特定点的尺寸,如一个孔的位置和大小,如有可能的话,应当出现在同一视图上.