CHECKING DESIGNS AND DRAWINGS Machinery's Handbook, 31st Edition
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Product Definition Data Set Integral Content: Related data as applicable for complete definition May be integral or referenced in the product
Notes
Analytical Data Test Requirements
Model (See Fig. 2)
Drawing
Revision History
Materials Finishes Processes
Printed Material (Related data may be manually or computer generated)
Fig. 17. Product Definition Data Set (ANSI/ASME Y14.41-2012) Supplemental Geometry: Geometric elements included in product definition data to communicate design requirements but not intended to represent a portion of the manufac tured product. Checking Designs and Drawings In order for production designs to be maintained at the highest level of consistency, a set of suggestions for checking models and drawings is provided below. The suggestions first concentrate on a review of the design parameters in a global sense, then on a detailed review of the drawings and/or model itself. It is recommended that these suggestions be followed in parts based on responsibility, by engineers, checkers, designers, detailers and any others involved in producing, reviewing and approving engineering models and drawings. Design Parameters.— Inspecting a New Design: When a new design is involved, first carefully inspect the general design and its parts in relationship to the assemblies as a whole, ascertaining that parts function correctly and assemble under all material condi tions. Additionally, determine if the parts have the proper relative proportions and that the general design satisfies constraints for strength, rigidity, bearing areas, appearance, manufacturability, ergonomics of assembly, direction of motion, no unnecessary inter- ferences, etc. Generate a digital simulation physical rapid prototype if necessary. If the design appears to be unsatisfactory in any aspect, or improvements appear to be possible, notify the person responsible for that aspect of the design. Checking for Strength: Physically inspect the design for strength, rigidity, and appear ance. Compare it with other designs used in similar service whenever possible, giving preference to the known working designs in such a comparison, unless the known designs are examples of unsatisfactory parts. If there is any question, perform applicable analysis on the model or, if required, manually compute the stresses and deformations. If the new design is for a larger version of an existing device, ascertain that any standard parts neces sarily increased in size will continue to be sufficiently strong to bear increased service loads. Materials Specified: For the design, consider the material specification in relationship to the various manufacturing process options available, such as molding, forging, a weld ment, or other method with which to form the rough shape. Then consider the machining operations to see whether changes in form or design will reduce the number of operations or reduce the machining cost. Parts should be designed with reference to the economical use of material, and whenever possible, utilize standard stock sizes and material readily obtainable from local sources. In the case of alloy steel, special bronze, and similar or exotic materials, confirm that the material can be obtained in the required size.
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