What you are asking is: what must be used for drawing a frame on a drawing, and what is its format? It is usually necessary to draw a rectangular box on the diagram. The format of the drawing frame shall generally include the following contents:

1. Title bar: used to display information such as drawing name, drawing number, version number and drawing date.

2. Border line: used to separate the drawing frame from the main body of the drawing, usually thick.

3. Dimension marking: used to mark the size and proportion of the drawing, generally in the lower left corner or lower right corner of the drawing frame.

4. Legend: used to explain the symbols and marks on the drawing, usually in the lower right corner of the drawing frame.

5. Signature column: used to record the information of reviewers, approvers and drafters of drawings.

6. The format of the drawing frame can be different according to different industries and standards, but the above contents are the common basic elements. When drawing a drawing frame, we should choose the appropriate line width and line type according to the specific requirements, and ensure that there is enough space between the drawing frame and the drawing body for subsequent modification and management.