SAE J2370 pdf download
SAE J2370 pdf download.Geometric Dimensions and Tolerancing for curved Hose.
3. Definitions
3.1 Geometric Dimensioning and Tolerancing (GD&T) is:
a. The engineering product definition methods that geometrically describe design intent and provide the documentation base for the design of the quality control and production systems.
b. A technique of communication between customer engineers and supplier engineers that promotes a uniform interpretation of the acceptance requirements for a component in terms of its dimensions and tolerances.
GD&T provides the method for dimensioning and tolerancing in a language that helps to eliminate confusing and inconsistent notes. It replaces them with symbols that refer to a common code, ASME Y14.5M: which is the American National Standard. This code describes the dimensions and tolerances of the component with reference to the relationship of Its features to each other and their functional interlaces with mating parts. assemblies, etc.
3.2 Reference to Standards Documents—When this document applies, there shall be a note on the drawing or in a document referenced on the drawing, which refers to ASME Y14,5M, SAE J20, and SAE J2370.
3.3 Reference to Gauging—This document and the ASME Y14.5M are not intended as gauging standards. Any reference to gauging is included for explanatory purposes only.
3.4 FIgures—The figures in this document are illuslrahons Intended only as an aid to the user In understanding the application of GD8T to curved hose. Any numerical values shown are for illustrative purposes only.
3.5 TheoretIcal Design Attitude—The theoretical design attitude is: The position of the hose when in me final installed attitude unless otherwise agreed upon by customer and supplier.
3.6 Boundary—The outside contour of the hose is controlled by a true position outer boundary tolerance zone The tolerance zone follows the basic centerline of the hose, and its zone is equal to the hose outside diameters’ MMC size plus the positional tolerance. The outside surface of the hose must reside within this boundary. To invoke this concept, the term BOUNDARY is placed beneath the feature control frame (see Figures 1 to 4).
4. Drawing Views
4.1 Proectlon—The drawing must specify either third (3rd) or first (1st) angle projection including the appropriate projection symbol.
4.2 MinImum Views—A minimum of two orthographic views is recommended on three dimensional hose shapes.
4.3 End View—A true end view of the hose, dimensioning any radially located features (orientation marks. stripes, etc.) to the next adjacent body iength This view is required for any radially located feature that Is used as a tertiary datum.
4.4 IdentificatIon—Views are to be identified such as: Top or Plan, and Bottom or Front.
5. Dimensions
5.1 Dimensions, Angles—All dimensions are to be in metric. Angles are to be in decimal degrees.
5.2 Origin—Dimensions may originate from any hose end.
5.3 Basic Dimensions—The contour of the hose must be defined wdh basic dimensions.
5.3.1 CO0RDNATE Box—Dimensions may be shown in a Coordinate Table or Chart based on the right hand rule (see Figure 5). All coordinate dimensions in a Table or Chart must be noted that: ‘AfI chart dimensions are basic’
5.3.2 XYZ DIMENSIONS
a. II charted, the XYZ location dimensions as installed are required.
b. Dimensions may be shown as ordinate dimensions on the hose, and should be indicated as basic.
6. Datums General—Features of the hose must be identified as datum features for the purpose of establishing geometric relationships imposed by a feature control frame. Daturns are theoretically exact points, axes, and planes. These elements exist within a framework of three mutually perpendicular intersecting planes known as the datum reference frame. In the datum reference frame, from left to right, the first datum Is the primary, the second datum is the secondary and the third datum is the tertiary. Sufficient datum features, those most important to the design of a part are chosen to position the part in the datum reference frame. This reference frame exists in theory only and not on the part. Therefore, it Is necessary to establish a method of simulating the theoretical reference frame from the actual features of the part. Due to the nature of a rubber hose (synthetic elastomeric materials) and being a non-rigid material subject to free state variation, and because its surface is curved or free-form, the datum planes may be described in one of two methods (referred to as methods 1 or 2) described as follows.
