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MAN Nutzfahrzeuge AG

WORKS STANDARD A accuracy of shape

June 2006

Tolerances for sheet metal parts in the driver's cab shell

M 3199-2

Symbols, values, details in drawings Dimensions in mm

This English version is a translation. In case of doubt or conflict the valid German-language original will govern.

Contents 1 2 3

Scope and purpose Specifications in drawings Tolerances for measurements and/or deviations in shape and position without tolerance specification 4 Tolerances for deviations in shape and position with drawing symbols 5 Actual specification of tolerances for measurements and/or deviations in shape and position 6 Procedure for measured exceeding of tolerances Appendix A1 Surface shape tolerance for contact surfaces t=1 Appendix A2 Single sided surface shape tolerance t=0.5 Appendix A3 Single-sided linear shape tolerance for cut edges t=2

1 Scope and purpose This standard applies to component dimensions specified in drawings and/or in NC data for sheet metal parts up to 3 mm thick manufactured without cutting, which are used in the driver's cab shell with the introduction of the "New vehicle generation" (NFG). It applies only for geometric data without tolerance specifications (see Table 2) and/or for standardised symbolic specifications (see Table 3) and then provided that assembly tolerances are not exceeded. General tolerances are always therefore to be included in tolerance calculations and analyses of joining functions. Tolerances which need to be smaller and/or can be greater than general tolerances for functional and/or production reasons shall be specified directly. The purpose of the standard is to permit deviations due to the production process and which have no effect on the function of the component. This should prevent higher production costs caused e.g. by additional operations and/or drawing and/or NC data revisions in the interests of achieving a commercially viable production. Note: All specifications regarding the identification of admissible tolerances relate to illustrations in drawings and/or on the 2D-CAD portion, not to the illustration of admissible tolerances in the 3D-CAD model. 2 Specifications in drawings The main standard number M 3199 is to be quoted in the component drawing in the text box (“general tolerances” field). In this case, the general tolerances according to Table 2 automatically apply for all geometry elements without any assigned tolerance symbols or specifications.

Continued on Page 2 to 7 Prepared by: Scheibenbogen

Released TDN:

Replaces: 1998-12

Material group no.:

2006-06; englisch MAN Nutzfahrzeuge Aktiengesellschaft, Munich works – Dept. Normung (TDN) x All rights reserved according to ISO 16016. Distribution and use of the contents are not allowed without written permission from MAN Nutzfahrzeuge Aktiengesellschaft.

Page 2 M 3199-2 : 2006-06 If tighter tolerances according to Table 3 are required for certain geometry elements due to the function, the appropriate symbol (see Table 3, column for drawing entry) must be stated against the affected geometry element in the drawing, and the sticker (A64 according to M3056-2) with content in line with Table 1, must be placed close to the text box. The tolerance values according to Table 3, column for value, then apply for the geometry elements with these symbols, while for all others the general tolerances according to Table 2 continue to apply. Tolerances, which need to be even smaller for function and/or production reasons, or which may be larger than the tolerances according to Tables 2 and 3, are to be specified directly with the symbol and tolerance value on the affected geometry element (see Section 5) Table 1 Standardised symbols Symbols

Explanation and values

For example: ,

A ,

Tolerances according to F

The symbols listed in Table 1 under “For example” simply serve to show that the tolerance values from Table 3 apply for this kind of entry.

M 3199-2 Table 3

For this reason, at least one of the symbols listed in Table 1 under “For example”, but not all of them, must actually be present in the appropriate drawing, while on the other hand further symbols from Table 3 can be entered in the appropriate drawing, which are not listed in Table 1 under “For example”. 3 Tolerances for measurements and/or deviations in shape and position without drawing entry Table 2 Tolerances for measurements and/or deviations in shape and position without drawing entry Measurements

Tolerances Limit deviations according to DIN ISO 2768-c

Angle dimensions

Limit dimensions according to DIN ISO 2768-c

Radii of curvature

+ 20%, at least however + 0.5

Hole-∅

Length measurements

general

at a < (r + 2s)

Nominal dimension

≤ 4,1

> 4.1 to 10

> 10 to 20

> 20 to 40

> 40

Limit deviation

+0,2 /- 0,2

+0,3 / -0,2

+0,6 / -0,2

+0,8 / -0,2

+1,5 / -1,5

1)

Positional tolerance for holes with no function

+ 40% in pulling direction t=3 (e.g.: holes for paint, wax or weight reduction)

Surface shape tolerance for surfaces with no function

t=3

Linear shape tolerance

t=3

Cutting and stamping burr Overlap notches Cut corners Sheet thickness reduction

0.3 (state cutting direction if necessary, e.g. for clip holes) up to 1mm admissible R 5 +0.5 25% for bevelling and first drawing of spot-welding flanges 30% when deep drawing

Clean cuts and notches 1)

a = Hole distance from bent edge r = radius of curvature s = sheet thickness

+2

Page 3 M 3199-2 : 2006-06 4 Tolerances for deviations in shape and position with drawing symbols Table 3 Tolerance values for symbolic drawing entries Drawing entry

Value 1,0 0,5 2,0 ∅1,0 ∅ ± 0,1

A

∅0,4 ∅ ± 0,1

F 1)

∅0,2

Explanation Surface shape tolerance for contact surfaces and flanges Single-sided surface shape tolerance for joining surfaces Joining side Single-sided linear shape tolerance for cut edges Positional tolerance 1) for holes with function, e.g. assembly holes Diameter and positional tolerance 1) for mounting holes (for single part) Diameter and positional tolerance 1) for fixing holes (for assembly)

Dimensions for determining location of shaped elements with positional tolerances are theoretically exact measurements

5 Actual specification of tolerances for measurements and/or deviations in shape and position Principles of representation of symbols and entries in drawings are determined in DIN ISO 1101. The actual specification of tolerances for measurements and/or deviations in shape and position is necessary only when the required values are defined neither by Table 2 (section 3) nor Table 3 (section 4). If appropriate the symbols according to Table 3 shall be used. 6. Procedure for measured exceeding of tolerance If, within the framework of the pilot sample test, individual local positions where the tolerance is exceeded are found (measured), these are to be recorded in the pilot sample test report and discussed with Design. For tolerance deviations of minor importance, which have no influence on the function of the parts, a test concession will be issued by the MN Pilot Sample Test Department, and this will be cleared by Design This test concession, together with the pilot sample test report, will be filed centrally in the MN Quality Department, in order to be accessible to all departments at the plant. The tolerance deviations will only be included in the construction drawing, if the tolerance is to be basically changed for function and/or production reasons and/or is to be taken into consideration without fail when replacing a tool within the framework of the target geometry. In all other cases, the inclusion in the construction drawing is not permissible, as this would be an accidental falsification of the target geometry and could affect the target geometry when replacing a tool.

Page 4 M 3199-2 : 2006-06 Appendix A1

1,0

Surface shape tolerance for contact surfaces t=1

Part 2 Part 1

assembly

Value entry required only in the case of deviation from general tolerance only in Tables 2 and 3

11,5

20

Part 1

Part 2

Drawing entry

Tolerance zone t=1

theoretically exact surface

Ball ∅ 1

t=1

Ball Ball∅ 1 possible shape of the actual f Part 1 Significance

Part 2

Page 5 M 3199-2 : 2006-06

Appendix A2

Single sided surface shape tolerance t=0.5

0,5

Part 2 Part 1

assembly Value entry required only in the case of deviation from general tolerance in Tables 2 and 3

11,5

20

Drawing entry

Part 1

Part 2

Tolerance zone t=0.5

Half ball ∅ 1

theoretically exact surface

t=0.5

Half ball ∅ 1 possible shape of the actual Part 2 Part 1 Significance

Page 6 M 3199-2 : 2006-06

Appendix A3

Single sided linear shape tolerance for cut edges

2,0

X

Value entry required only in the case of deviation from general tolerance in Tables 2 and 3

X

Drawing entry

theoretical cut edge

t=2

t=2

Significance

Page 7 M 3199-2 : 2006-06

Quoted standards DIN ISO 1101

Shape and positional tolerance; general, definitions, symbols, drawing entries

DIN ISO 2768

General tolerances; lengths and angle dimensions

M 3056-2

Implementation of Drawings, Repeated and collective data in drawings (pattern)

Earlier issues:

M 3199-2 / 1998-10, 1998-12

Changes:

Compared with issue 1998-10, the following changes have been made: - In Table 3 the tolerance zone of the positional tolerances was limited to the diameter (diameter symbols added). Compared with issue 1998-12, the following changes have been made: - Section 2 completely revised. - Section 6 added.