Simplified and Specified Representation(简化画法与规定画法)

Simplified representation is a drawing method for representing drawings in simplified but comprehensible format,whereas avoiding distortions in terms of intrinsic scales and structures. The following are some common uses of simplified representation.


Simplified representation of the same feature(相同结构的简化画法)

1) If a part contain sseveral repetitive features which are distributed following certain rules (suchas gear, groove, etc.), it is only needed to draw a portion of such features and use continuous thin lines to represent the rest, however, the number of all features must be labeled on the part drawing, as shown in Fig.6-59.


If a repetitive feature is a particular set of holes (such as round holes, screw holes, counter bored holes, etc.) with an unified diameter, only draw one or portion of them for representation, whereas represent the rest holes with dashed dotted lines to indicate the center position. It should be noticed to mark the number of holes on the detail drawing, as shown in Fig. 6-60. 


2) Fig.6-61 shows the drawing method of holes, which are distributed equably around the axis of a column inform flange or similar parts.


Simplified representation of projection(图形中投影的简化画法)

1) Structures with a small pitch in a part could be drawn according to its small end if it is represented in one view, as shown in Fig.6-62.


2) If a circle or an arc has the included angle of 30°or less than 30°to projective plane, its projection can be represented with a circle or an arc directly, as shown in Fig. 6-63.


3) Intersection of small structures on a part can be simplified or omitted on other views if it has been expressed clearly in one view, as shown in Fig. 6-64.


4) Small fillets or 45ºchamfers is permitted to omit, but they should be dimensioned or illuminated in engineering requirements,as shown in Fig.6-65.


5) The view of symmetrical part can be drawn with just a half or a quarter of it, and two continuous thin lines parallel with each other should be drawn at the two ends of center lines, as shown in Fig.6-66.


6) Partial views of symmetrical structures can be drawn as express shown in Fig. 6-67.

6) 对称结构的局部视图可按图6-67所示方法绘制。

7) Long parts (such as axes,poles, and so on), which has constant or regular profile along its length direction, can be simply represented by cutting off the middle portion of the part,whereas keep only the two ends and represent their cuts with continuous thin irregular lines, as shown in Fig. 6-68.


8) When a view cannot clearlyshow a plane, a plane symbol (with two thin diagonal lines) can be added on theface, as shown in Fig. 6-69.

8) 当图形不能充分表达平面时,可用平面符号(用两条细实线画出对角线)表示,如图6-69所示。

9) Reticulation material, weaving material,and diamond knurling should be represented in simplified forms, which can be drawn partially with continuous thick lines and attach to outlines, also they can be marked with the default relevant annotation instead, as shown in Fig.6-70.

9)网状物、编织物及机件上的滚花部分,一般采用在轮廓线附近用粗实线局部画出的方法表示,如图6-70所示, 也可省略不画,仅作如图所示的标注。


1) For ribs, spokes, and thin-walled structures, section symbols need not to be drawn if they are cut lengthwise. However, they should be distinguished from the other structures with thick lines, as shown in Fig.6-71.

1) 对于机件上的肋板、轮辐及薄壁等,如按纵向剖切,这些结构都不画剖面符号,而用粗实线将它与其邻接部分分开,如图6-71所示。

2) A revolved body with symmetrically located ribs, spokes and holes is shown in the section with those symmetrically features rotated to the cutting plane, as shown in Figs.6-71 and 6-72.

2) 当机件回转体上均匀分布的肋板、轮辐、孔等结构不处于剖切面上时,应将这些结构旋转到剖切面上画出,如图6-72所示。