Принципи побудови креслень посудин, що працюють під тиском
1. Principles of View Selection
- (1) The number of views (including directional views, cross-sectional views, etc.) should be minimized on the premise of clearly representing objects.
- (2) Avoid using dashed lines to represent the contours and edges of objects.
- (3) Avoid unnecessary repetition.
2. Drawing principles
For processing, assembly, and other needs, each piece of equipment, component, or part should be individually drawn with drawings.
The principle of not requiring separate drawings is as follows:
(1) National standards, professional standards, and other standard components and purchased parts.
(2) For riveted and welded parts with simple structures and whose dimensions, graphics, and other information have been indicated on the component diagram, they do not require mechanical processing (except for the processing of weld grooves and a small amount of drilling)
(3) If several castings need to be prepared for mold marking together during manufacturing, they should be drawn according to the component diagram and not separately. At this point, all necessary information for manufacturing the part must be indicated on the component.
(4) Connecting parts such as bolts, nuts, washers, flanges, etc., that meet the standard in size, although their materials differ from the standard, do not draw separate part drawings. But indicate the specifications and materials in the detail column, and indicate in the remark’s column that “the dimensions shall be by ××× Standard. “ At this point, the “drawing number or standard number” column in the parts list should not indicate the standard number.
(5) Two symmetrical and oppositely oriented parts should generally be drawn separately. But for two simple symmetrical parts, only one can be drawn without causing construction errors. But each piece should be labeled with a different part number and explained in the drawing. This drawing represents the part number ×， And part number ×, And part number × Symmetry between left and right (or up and down).
(6) Parts with the same shape and simple structure and can be represented by the same pattern; generally, no more than 10 different variable parameters can be drawn using table drawings but must comply with the following regulations:
- ① Common invariant parameters and textual explanations must be indicated in the drawing, while variable parameters are indicated by letter codes;
- ② The table must include the part number, quantity, and quality of each variable parameter.
The principles for drawing component diagrams separately are as follows.
- (1) Due to the needs of processing technology or design, component drawings should be drawn for components that must be assembled before mechanical processing. For example, equipment flanges with short joints, large gears composed of two halves, worm gears composed of two different materials of parts, etc.
- For simple components without drawing component diagrams, it should be indicated in the part diagram that they need to be combined before mechanical processing. For example, “× The surface needs to be matched with the part number × Processing after welding “and other words.
- (2) Components that are detachable or nondetachable and have independent structures that require drawing component diagrams to represent their assembly requirements, mechanical properties, and usage should be drawn with components such as mixing transmission devices, split bearings, couplings, etc.
- (3) A component diagram should be drawn for complex посудина під тиском shells.
- (4) Cast or forged parts should have component drawings drawn.
3. Principles for drawing enlarged images
The welding seams between the cylinder and the head, the welding seams between the reinforcement ring and the cylinder or head, the welding seams between the thick wall pipe reinforcement, the welding seams between the cylinder and the tube plate, the welding seams between the cylinder and the skirt, and the connecting welding seams need to be enlarged.