PV3370_EN_2018-12-01.pdf

Vertraulich. All rights reserved. No part of this document may be transmitted or reproduced without prior permission of a Standards Department of the Volkswagen Group.
Parties to a contract can only obtain this standard via the B2B supplier platform “”.
F o r m F E 41 - 09.06
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 .
N u m e r i c a l n o t a t i o n a c c o r d i n g t o I S O p r a c t i c e (s e e V W 01000).
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Table 1
Code letter Requirement
A Particle size < 300 µm
B None
C Particle size < 600 µm
D Particle size < 900 µm
E Particle size < 1 200 µm
F Particle size < 300 µm, but one particle per part < 600 µm permissible
G Particle size < 600 µm, but one particle per part < 900 µm permissible
H Particle size < 900 µm, but one particle per part < 1 200 µm permissible
I Particle size < 1 200 µm, but one particle per part < 1 500 µm permissible
For F to I: Design Engineering has the freedom to also establish several particles of the next size class (e.g. F, but instead of one, three particles are permissible) or the combination of several size classes (e.g. F, but instead of one particle < 600 µm, three particles
< 900 µm are permissible) in the form of a drawing note or deviation permit.
Table 2
Code number Requirement
0,005 < 0,005 mg per part
0,01 < 0,01 mg per part
0,03 < 0,03 mg per part
0,05 < 0,05 mg per part
0,1 < 0,1 mg per part
0,3 < 0,3 mg per part
0,5 < 0,5 mg per part
1 < 1 mg per part
3 < 3 mg per part
5 < 5 mg per part
In justified cases, other code numbers can also be used (e.g. 6, 10 or 30).
Table 3
Detail criteria Requirement
Abrasives and loose weld spatter are not permissible on principle.
external.
a Position:
b Disassembly foreign matter is not considered to be residual foreign matter.
c Primary steel particles not permissible; fluff an
d light alloy not taken into account in
standard quantities when restricting particle size.
d Primary light alloy particles not permissible; fluff not taken into account in standard
quantities when restricting particle size.
e Metallic particles not permissible.
f Primary organic particles not permissible.
g Hard particles not permissible.
h Magnetic particles not permissible.
i Position: internal hydraulic circuit.
y To be tested under conditions resembling operation, e.g. with pumps rotating under their own power or with external drive, or with valve bodies under test bench
conditions with activation of all operating states.
z To be checked in assembly (undismantled).
See section "Requirements".
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3.3 Specimen quantity
The necessary minimum quantity depends on the permissible mass of the residual foreign matter and the weighing equipment used for evaluation.
It is oriented toward the relevant component or assembly, the sensitivity of the area of application and the apparatus available for determining the mass of the residual foreign matter. The specimen quantity is calculated according to the formula:
rt in mg
ter per pa oreign mat residual f e mass of Permissibl tor n mg x fac solution i Balance re quantity pecimen 50
S =
Example: With a code number of 0,1 from Table 2, the result is 50 specimen parts when using a balance with a resolution of 0,1 mg. If there is only a balance with a resolution of 1 mg available, the result is 500 specimen parts. 3.4 Equipment, reagents
─ Laboratory ultrasonic cleaning unit
─ Diaphragm liquid pump ─ Line filtering unit ─ Vacuum filtering unit
─ Analytical balance (resolution 0,1 mg)
─ Stereomicroscope with ocular micrometer (25x magnification) ─ Nylon fibrous filter, diameter: 47 mm or larger, cold-punched
─ Safety cold cleaning agent (e.g. Volkswagen material number 29.2829) ─
Petroleum ether
3.5 Test procedure 3.5.1 Specimen parts
Supply parts and in-house manufactured parts in the type intended for final assembly. The parts shall be removed from the unopened original packaging. The minimum specimen quantity is calculated according to Section 3.3. 3.5.2 Cleaning
The parts are cleaned in an organic hydrocarbon-based solvent.
Safety cold cleaning agents of flash point hazard class A3, free of chlorinated hydrocarbons and aromatic hydrocarbons, have been tried and tested for this purpose. Cleaning according to VDA 19, using:
─ Low-pressure spraying with wash bottle
─ Medium-pressure spraying by means of spray gun in cleaning cabinet ─ Ultrasonic cleaning, rinsing in solvent
─
Flushing from both sides by means of diaphragm pump (interior flushing)
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The task of the test fluid is to strip the foreign matter burden on the components as completely as possible. The relevant process is accordingly selected for the component and is deemed to be appropriate when a second test of the same part shows a residual foreign matter quantity < 10% of the first test (fading curve in accordance with Section 4.1 of VDA 19). The cleanliness of the test fluid has a direct influence on the blank value and increases the value if it is contaminated.
The cleanliness of the fluid used is to be ensured by means of appropriate filtration.
The blank value of the relevant test procedure is to be determined without the specimen parts.
If a blank value exceeds 10% of the residual foreign matter quantity permitted or to be expected, the testing devices and testing tools must be cleaned again.
3.5.2.1 Components with a surface easily accessible on all sides
Clean specimen parts using a sufficient quantity of the cleaning agent, either one after the other or all together, depending on the size of the parts.
When spraying, the total fluid quantity is to be distributed evenly over the components.
During ultrasonic cleaning, the time is to be limited to 60 seconds. The parts are to be flushed using a wash bottle containing clean cleaning agent when they are removed.
Test vessels made of glass or stainless steel are to be used, no damping materials such as plastic. During rinsing, approx. 50 strokes are to be executed within 60 seconds.
A conical vessel fitting the specimen is used, so that the specimen is approx. 6 mm above the bottom in order to ensure that the specimen can come into contact with the fluid on all sides.
3.5.2.2 Components with partial residual foreign matter requirements
Components for which only partial areas of the surface or only the interior are subject to a residual foreign matter requirement or for which different interiors are subject to different regulations (e.g. in the case of a housing with different requirements for the hypoid space and ATF space and no requirement for the exterior) are sprayed with sufficient quantities of fluid in the non-regulated area first in order to prevent falsification of the following procedure. As a rule, the fluid is discarded or supplied for gravimetric analysis. After that, the chamber or surface to be tested is sprayed or flushed. The surfaces not to be tested are covered. If this is not possible, only the relevant zone or chamber is flushed.
3.5.2.3 Hollow bodies such as hoses, tubes, lines, radiators, etc.
Hollow bodies, for which generally only the interior is subject to a residual foreign matter requirement, must be alternately flushed with cleaning fluid.
This is done by pumping 2 liters of cleaning fluid per minute through the component from both sides for 3 minutes using a commercial piston diaphragm pump.
The dirty cleaning agent that runs out is then directed through the test filter.
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3.5.3 Special case: tapping
E.g. for dry clutch disks
In the case of dry clutch disks (in-house mounting), the dirt quantity is determined by tapping them on a hard rubber plate 20 times (test plate approx. 10 x 20 cm, Shore A hardness 80) instead of by the standard test procedure.
Detailed description: 10 disks are placed on both index fingers, allowed to fall from between the hands onto the hard rubber plate from a height of approx. 5 cm and immediately picked up again. This procedure is repeated 19 times.
The procedure is performed on a suitable surface (e.g. household tray with raised edge), and the disk particles or the dust is weighed.
In the case of oiled clutch disks from clutch assemblies and previously operated transmissions, the dirt quantity is determined by rinsing the disks in safety cleaning agent. Ultrasound must not be used due to the danger of disk disintegration.
instructions
3.6 Work
The tests are carried out specifically for each component. Work instructions are then to be compiled taking into account the details from VDA 19. Examples can be found in the VDA Appendix.
3.7 Filtration and filters
Filter the cleaning agent containing residual foreign matter. A vacuum filtering unit with a constant-weight, pre-weighed filter is used for this purpose (accuracy 0,1 mg). Then re-rinse the filter and residual foreign matter with petroleum ether and dry to a constant weight (observe safety regulations).
Filter type: Nylon fibrous filter, 15 µm mesh width:
Diameter: 47 mm (larger diameters are permissible)
3.8 Evaluation
The mass of the residual foreign matter is determined by re-weighing the constant-weight dried filter, the result in mg/part is divided by the number of specimens.
The blank value is to be taken into account in accordance with Section 3.5.2.
The particle size and, if applicable, the composition are then determined.
This is generally done visually/microscopically. In special cases, automated particle counting systems and REM-EDAX are deployed.
Note that all dimensions must be within the specification when evaluating the particle size.
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4 Description
For examples see Table 4
Table 4
Drawing note Particle size Mass of residual
foreign matter
Detail criterion A 5 < 300 µm < 5 µm None
A i
B a 5 < 300 µm internal, no
limit external < 5 mg, total interior
and exterior
Position: i = interior,
a = exterior
A 1 z < 300 µm < 1 mg Test undismantled
A 0,5 b < 300 µm < 0,5 mg Foreign matter resulting
from dismantling is not
taken into account.
F 0,002 < 300 µm, but one
particle < 600 µm
permissible
< 0,002 mg None
5 Sources of supply
Filters: Disks made of SEFAR NITEX 03-15/10, diameter: 47 mm, cold-punched
SEFAR GmbH
Dr.-Fritz-Huber-Strasse 73, DE-83512 Wasserburg
Tel. 0049 (0)8071 90400-0
Fax 0049 (0)8071 40787
www.sefar.de
6 Referenced
standards1
VDA 19 Prüfung der Technischen Sauberkeit; Partikelverunreinigung funktionsrelevanter Automobilteile (Testing of Technical Cleanliness – Contamination of Automotive
Components Relevant for Function by Particles – only available in German)
1 In this Section, terminological inconsistencies may occur as the original titles are used.。