Vertragspartner erhalten die Norm nur über die zuständige Beschaffungsabteilung.
Confidential. All rights rerved. No part of this document may be transmitted or reproduced without the prior written permission of the Volkswagen Group, EZTN, Standard Department.
Parties to a contract can only obtain this standard via the responsible procurement department.
VOLKSWAGEN AG
F o r m F E 41 - 10.99
T h e E n g l i s h t r a n s l a t i o n i s b e l i e v e d t o b e a c c u r a t e . I n c a s e o f d i s c r e p a n c i e s t h e G e r m a n v e r s i o n s h a l l g o v e r n .
Q U E L L E : N O L I S (N o r m v o r A n w e n d u n g a u f A k t u a l i t ät p r üf e n !/C h e c k s t a n d a r d f o r c u r r e n t i s s u e p r i o r t o u s a g e )
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TL 188: 2000-03
3.2 Material
3.2.1 Ba Material of the Screw/Nut/Bolt/Bore
Acc. to drawing
3.2.2 Screw Surface Protection
Acc. to drawing
3.2.3 Coating
3.2.3.1 Material
PFA colorless (white)
3.2.3.2 Coating Length, Area and Thickness
The coating must be applied to the contact surfaces of the interior threads of nuts, threaded plates, bores and to the contact surfaces of the exterior threads and bolts. The coating should have a uniform, continuous appearance, with no drops, streaks and flaking areas.
Bad on the different processing methods in the plants, the thickness of the coating on the thread tip or the thread ba can be different. However, the screwing and unscrewing torques must be guaranteed (e Table 1).
If not otherwi indicated on the drawing, the coating position and the coating area should corre-spond to the following limitations:
The coating on parts with external threads should extend to the thread runout for parts with a shank and over the entire thread length for parts with threads approximately up to the head. There must be no coating adhering to the head and the adjacent or load-bearing surfaces of bolts, the hexagonal surfaces of the nuts and their adjacent or load-bearing surfaces, the weld rings, points or projections, surfaces and all head surfaces of welded screws, bolts and nuts.
In order to guarantee the function, the coating must completely cover the starting pha of the threads on the side of the nuts to be welded.
Force
3.3 Torque/Testing
To test a batch, a minimum of 10 randomly lected parts are required. The permissible thread-in torque (Table 1) and the calculated pre-load forces per VW 011 26-1 and VW 011 26-2 are the criteria.
For testing the parts, standard test washers are ud as load-bearing surfaces, as well as phos-phatized and oiled nuts and bolts that are of approximately equal strength. The test parts must be inspected for proper gage size. The values of the thread-in torques must correspond to the specifi-cations in Table 1. The maximum thread-in or running torques can be somewhat higher for screws or nut surfaces that are not true to gage size. For quality problems, the results with true to gage size phosphatized and oiled surfaces apply.
The testing force of the nuts must correspond to the requirements per EN 20 898-2 and EN ISO 898-6.
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TL 188: 2000-03
Table 1: Thread-in torques of stamping and weld nuts, and bolts
Dimensions Initial thread-in or running torque
max. (Nm)
M60.5
M8 1.0
M10 2.0
M12, M12 x 1.5 3.5
M14 x 1.5 5.0
4 Test
Torque preload measurements are taken with calibrated load cells or friction test stands, for exam-ple. The friction radii of the screw mates must be defined or mathematically adjusted according the specifications per VW 011 26-1. If the specifications are kept, the specified limits per VW 011 26-1 must be achieved.
Standards
5 Referenced
VW 011 26-1Joining, Tightening Torques for Screw Connections
VW 011 26-2Joining, Tightening Torques for Screw/Bolt Asmbly Beyond the Elastic
Limit
VW 011 55Vehicle Supply Parts, General, Approval of First Supply and Changes
VW 911 01Environmental Standard for Vehicles, Vehicle Parts, Materials, Operating Fluids, Avoidance of Hazardous Substances
DIN EN 20 898-2Mechanical Characteristics of Joining Elements; Part 2: Nuts with Defined Testing Forces; Coar Thread (ISO 898-2: 1992)
DIN EN ISO909-6Mechanical Characteristics of Joining Elements; Part 6: Nuts with Defined Testing Forces; Fine-Pitch Thread
