Mercedes-Benz DBL 8440Supply Specification
Date Published: 2009-06
Total No. of Pages (incl. Annex): 12 Person in Charge: Dr.Hes
Plant 010; Dept.: PWT/VWO
Phone: +49-(0)711 17-23506
Copyright Daimler AG 2009
Parts manufactured from ferrous materials
with inorganic coating
(zinc flake coatings)
Teile aus Einwerkstoffen mit
anorganischer Beschichtung (Zinklamellenüberzüge)
Foreword
This Supply Specification specifies the requirements for components protected against corrosion by means of zinc flake coatings.
The latest version of this document will be available through the standards information systems of Daimler AG and Mercedes-Benz following relea.
Changes
The following changes were carried out compared with edition 2006-07:
− New layout of DBL
− Product versions 8440.00 and 8440.10 which are barred for new designs are no longer described in this Supply Specification
− Product version 8440.60 with specific requirements for larger components created, and higher resis-tance properties and tighter specifications defined
− Reference to period of retention of the coating documents included
Table of Contents
1Scope (3)
2Normative references (3)
3Abbreviated material designation for documentation (4)
4Abbreviations, acronyms, definitions, & symbols, (4)
5Regulated substances and recyclability (4)
6Technical data (5)
6.1Process description (5)
6.2Basic materials (5)
6.3Material strength (6)
6.4Coatings (6)
6.5Special component requirements (7)
6.6Coefficients of friction / Sliding behavior (8)
7Tests (8)
7.1Dimensional stability test (8)查找我的iphone
7.2Corrosion resistance test (8)
7.3Cathodic protection capability test (9)
7.4Layer adhesion test (9)
8Duties of the supplier (10)
9Samples (10)
10Deliveries (10)
11Marking (10)
12Packaging (10)
13Storability (11)
14Special instructions (11)
15Complaints (11)
16Environmental protection regulations/Industrial safety (11)
Table 2 (12)
Table 1 Product versions (PV), overview
Coating inorganic, zinc flake coatings
Parts category / Color without
thread
without
thread
with
thread
with
thread
larger sheet steel
components, with cavities,
if applicable
Lubricant (integrated
into coating)
PTFE PTFE
Silver gray 1).20 .22 3).30 .40 3).60
Black 2).21 .23 3).31 .41 3)
1): Standard finish
2): Black finishes for special cas
3): Blocked for new designs
春节给领导的祝福语
1 Scope
This DBL describes the special requirements and properties as well as characteristics of parts coated with zinc flake coatings.
The purely organic coatings according to product versions .00 and .10 previously specified in this DBL have no longer been acceptable since 2006-01 and are no longer listed in this DBL. For any components which may still be supplied in accordance with the product versions, DBL 8440, edition 2006-07, shall apply.
Blocking note for product version 8440.60:
In the ca of surface treatment of components with coating according to 8440.60, any change in the coa-ter, pretreatment technology or product(s), coating material(s), coating system and location during the product development pha shall be subject to prior approval by the development units responsible, the corrosion experts responsible at EP/CRK, as well as Production and Materials Engineering (PWT/VWO), and during the production supply pha, by the QM units of the plants at Daimler AG.
Renewed initial sampling is a precondition for any change of the parameters described above. For further information, also refer to Chapters 9 and 10 of this DBL.
Submission stage 3 for initial sample inspection required.
Note regarding specific commercial vehicle parts
In the commercial vehicle ctor which is not affected by the ELV directive (ban on Cr(VI)), wheel fasten-ers (wheel nuts, wheel bolts), for example, are for functional reasons coated with specially lected zinc flake systems. For such components, DBL 8440 edition 05/2002 may still be deemed valid. The DBL with issue date shall be indicated on the relevant drawings. The same principle applies to other components in the commercial vehicle ctor which cannot be changed at least for a
适合旅游的地方limited time for functional reasons.
2 Normative references
DBL 7399 Supply Specification; Supply Specification - General Requirements - Environ-
mental protection, hazardous substances, and associated coatings. General
conditions and test methods
DBL 8585 Supply Specification - Supply Specification - General Requirements - Envi-
ronmental protection, hazardous substances, d angerous goods - Negative
substance list for the lection of materials
DBL 9410 Supply Specification; Testing of coefficients of friction of threaded parts
DBL 9440 Supply Specification; Fasteners with metric thread; Surface protection and
supplementary technical delivery conditions
DBL 9441 Supply Specification; Surface protection for fasteners f or direct screw connec-
tion in metal sheets and plastic (non-metric threads )
DBL 9460 Supply Specification; Screws, bolts and studs with micro-encapsulated liquid
adhesive
DBL 9599 Supply Specification; Screws of property class 120 and 12.9
DIN EN ISO 6270-2 CH Paints and varnishes - Determination of resistance to humidity
Part 2: Procedure for exposing test specimens in condensation-water atmos-
pheres
DIN EN ISO 9227 NSS Corrosion tests in artificial atmospheres - Salt spray tests
(ISO 9227:2006); German version EN ISO 9227:2006
DIN 50969 Testing of high-strength steel building elements for resistance to hydrogen-
induced brittle fracture and advice on the prevention of such fracture
DIN EN ISO 15330 Fasteners - Preloading test for the detection of hydrogen embrittlement -
Parallel bearing surface method (ISO 15330:1999); German version of EN ISO
15330:1999
DIN EN ISO 10683 Fasteners - Non-electrolytically applied zinc flake coatings
(ISO 10683:2000); German version of EN ISO 10683:2000
MBN VDA 235-101 Lubrication of threaded fasteners
MBST Mercedes-Benz Special Terms
3 Abbreviated material designation for documentation
For drawings in the block for surface protection: e.g. DBL 8440.20
胜人者有力For components according to DBL 8440.60, the coating company, the location of the coating plant an
d the products to be ud shall additionally be specified in the drawing block / in the field "Notes and Remarks" of the master data of the 3 D model.
mibtExample: Company Coating PLC, Plant Anyplace PT1 4PG,
coated with zinc flake bacoat, type "Ba1“ Company A.N.Other
and top coat, type Top2, Company A.N.Other
4 Abbreviations, acronyms, definitions, & symbols,怀孕初期下面分泌物会增多吗
Zinc flake coating:Esntially inorganic, thin coating with cathodic corrosion protection capability,
characterized by the fact that zinc and, to a lesr extent also aluminum flakes,
are applied to a component surface from a dispersion. The liquid constituents
处级单位
will evaporate during the subquent baking process. In order to achieve opti-
mum corrosion protection, the coating shall normally be applied and baked at
least twice. Instead of using two zinc flake bacoats, a combination of one or
veral zinc flake ba coats with an organic or inorganic top coat of a different
composition which may also contain metal flakes is customary.
PV:Product version according to this DBL, e.g. DBL 8440.20
5 Regulated substances and recyclability
All materials, procedures and process for the manufacture of components according to this DBL shall conform to the current regulatory (governmental) requirements regarding regulated substances and recy-clability; e Negative Substance List for the Selection of Materials according to DBL 8585 (or Mercedes-Benz Special Terms).
The EU End–of-Life Vehicle Directive including the requirements with regard to freedom of the coatings from Cr-VI shall be complied with.
Due to the detection problems associated with chromium (VI) in zinc flake coatings, the application of compounds containing chromium of other valence states is also not permitted.
Waiver for parts with previous Cr(VI)-free coatings:
Parts according to this DBL which already complied with DBL 8585 on 2006-06-30 and for which the free-dom of the coating structure from Cr(VI) has been attested by the supplier, may continue to be supplied, unless otherwi required, according to the approved initial samples until the next initial sampling. The attestations shall be transmitted by the supplier of the components to the QM departments of the plants where the parts are installed.
data
6 Technical
6.1 Process description
In fully hardened condition, zinc flake coatings shall consist predominantly of metallic components. They contain zinc (≥ 65%) and up to 10% aluminum flakes.
Before coating with zinc flakes, the component surface shall be pretreated (e.g. cleaning, blasting, phos-phating or combination of different methods) to ensure proper adhesion of the layer. Evidence of the suit-ability of the pretreatment method for the parts to be coated shall be provided by means of state-of-the-art examinations.
For small parts, the zinc flake coating shall be applied by immersion in a Zn(-Al-) flake dispersion, and for larger parts by spraying or immersion in the dispersion. This is normally followed by spinning off any ex-cessive dispersion and baking the coating whereby the liquid constituents of the dispersion evaporate and a metallic contact between the flakes themlves and between the flakes and the substrate is formed. This generates an electrically conductive inorganic surface coating which ensures cathodic protection for the component. This does not mean that the coatings are generally suitable for electrical contacting.
Flakes oriented parallel to the surface promote good corrosion protection and reduce ttling in the threaded connection areas.
In order to eliminate defects and increa corrosion protection, the dipping, baking and spinning process shall be performed at least twice or even more frequently.
For larger parts (including tho with interior surface areas), e.g. according to PV .60, it may be possible to dispo of the spinning off of excessive coating material. Care shall be taken to ensure, however, if applicable by means of suitable blow-off technology following immersion, to ensure that no unacceptable coating agglomerations occur, in particular not in functional areas such as locations of threaded connec-tions.
By applying specific products with and without metallic components during this process, the complete lay-er properties can be adjusted in a targeted way in the top coat(s) with regard to visual (e.g. black color) or functional requirements (e.g. integration of lubrication additives or incread resistance to chemicals, e.g. to wheel cleaners).
If a predominantly organic coating is ud as top coat for product version 8440.60, a coat thickness ratio of approx. 2/3 for the zinc flake ba coat and approx. 1/3 for the top coat is required.
As white zinc corrosion products forming on black surfaces tend to have a more negative visual impact than tho forming on silver surfaces, black surfaces in accordance with this DBL shall only be ud in special cas and even then only if evidence can be provided that the required coating quality can also be achieved on concrete components.
The baking temperature shall be ≥ 180 °C; any detrimental effect on the basic material properties shall be avoided in principle. Unless otherwi agreed for a concrete component, coating process shall be -lected for screws and bolts which undergo final rolling to increa their fatigue strength, during which the baking temperature does not exceed 240 °C.
6.2 Basic materials
The components designated for coating shall not exhibit any material, machining or surface defects, which could impair the corrosion protection and/or the appearance of the coatings.
Any contamination on the surface of the parts to be treated (corrosion products or scale, oil, grea, dirt etc.) shall be completely removable by normal application of the automatic cleaning and pre-treatment facilities.
In the ca of coatings according to DBL PV .60, in particular, the coater shall check at appropriate inter-vals that no contamination impairing the adhesion and/or the coating quality is prent on the part sur-faces to be coated. For parts with cavities and surface areas lying inside, destructive methods shall be ud for this purpo, if necessary.
自制原始凭证Weld ams and heat-affected zones shall be pretreated so that silicate, slag and oxide residues are re-moved to an extent that allows proper pretreatment / coating without impaired adhesion.
