Corporate Guideline 500B0332
Specification of surface coatings 9th issue, 2006-05
Page 1 of 5
Approved by Technical Advisory Group – Engineering, Torben Funder-Kristensen Language: en
Contents
Item Title Page
0 Information ............................................................................................................1
1 Scope .....................................................................................................................1
2 Field of application................................................................................................1
3 General...................................................................................................................1
4 Surface coatings.....................................................................................................2
5 Statements on drawings and in instructions ..........................................................3
6 Designations ..........................................................................................................3
7 Cross-reference: new and old designations for surface coatings...........................4
8 References .............................................................................................................5
9 Bibliography ..........................................................................................................5
0 Information
This Guideline replaces corresponding sections in previous standards for the specifica-
tion of surface coatings.
The methods and designations used for specifying surface coatings are based on DIN
50960-1, DIN 50960-2 and EN 1403, and have been adapted and abbreviated to suit
Danfoss requirements.
This Guideline doesn’t deal with thermochemical heat treatment processes as e.g. case
hardening (see 500B0401), nitriding, nitrocarburizing, boronizing etc.
1 Scope
This Guideline determines how surface coatings shall be specified in technical docu-
mentation for Danfoss products.
2 Field of application
This Guideline is recommended to be followed throughout the Danfoss Group.
3 General
The coatings named in this Guideline are to be designated as stated.
In cases where coatings are required which do not appear in this Guideline, they are to
be specified
- either in accordance with an international standard or national standard, and with
reference to the standard concerned.
- or by referring to a Danfoss Standard/Guideline, or an instruction in which the
requirements are stated.
Painted surfaces are recommended in order to conform with the requirements of
500B0286.
Corporate Guideline 500B0332
9th issue, 2006-05 Page 2 of 5
4 Surface coatings
Surface coatings are to be specified by base material, coating type and thickness. In ad-
dition, specifications can be supplemented to the extent necessary by further require-
ments for or information on, for example, subsequent phosphating or chromium-plating
or other information on other types of surface treatment.
Classification code for coating comprises:
1. The chemical symbol for the basis material followed by an oblique stroke
the following designations shall be used:
Fe for iron, steel, cast iron, etc.
Zn for zinc and zinc alloys
Cu for copper and copper alloys
Al for aluminium and aluminium alloys
NM for non-metal
PL for synthetic material (plastic)
2. The chemical symbols for type of coating
Ag for silver
Ni for Nickel
Zn for zinc
etc.
The type of surface coating shall be specified by its chemical designation, also if
the coating is an alloy. See designations in clause 6.
3. A number indicating the minimum thickness, in μm, of the coating
As an exception, if a maximum coating thickness is also required it is to be speci-
fied as follows: Ni 25min/35max (Nickel coating min: 25 μm, max: 35 μm)
4. Any additional requirements on the surface coating and finishing shall be specified.
Such requirements include chromating, phosphating, the degree of gloss, etc.
For example, a fastener that is to be zinc coated and subsequently chromated shall
be specified as follows:
Fe / Zn8c2TLP
a. Fe is the basis metal
b. Zn is the coating
c. 8 is the thickness of the Zn-coating in μm
d. c refers to the chromating
e. 2 is the class of the chromating (see table 1 in ISO 4042)
f. TLP (Thick Layer Passivation) is the designation of the chromating.
TLP is an alternative to yellow chromating (chrome (VI)), which goes out due
to the RoHS- and ELV- Directives.
The TLP-designation is chosen as indication on Danfoss drawings; even
though it is not yet an international standard.
5. When several coatings of different materials are required, the material and thick-
ness is to be stated for each coating
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9th issue, 2006-05 Page 3 of 5
6. Fasteners shall always be specified with further requirements in accordance with
ISO 4042 system B.
Zink coated iron and steel products with supplementary heat treatments are to be
specified in accordance with EN 12329 (examples in appendix C).
See clause 6 and the references and bibliography for details on specifying
other surface coatings and parent materials.
5 Specifications on drawings and in instructions
The requirements for specifications on drawings are given in 500B0318. The thickness
of coatings shall be observed at points on the surface that can be touched by a ø20 ball.
Other requirements shall be stated on the drawing.
In instructions and other documentation the words “Surface coating” shall preface the
coating designation.
− For example: “Surface coating Ni 5”, Surface coating NiP(11) 8” (11 in the bracket
specifies the phosphorous percentage, see also clause 6 for Nickel phosphorous).
6 Designations
Coating Designation Explanation
X = Coating
thickness in µm
Electrodeposited
Silver Ag X
Gold Au X
Nickel Ni X
Ni X b b = bright nickel
Ni X p p = dim/semi-bright nickel, polished
Ni X d d = 2 or 3 nickel coatings
Ni X s s = dim/sateen/semi-bright nickel
Chromium Cr X
Tin Sn X
Copper Cu X
Zinc Zn X
Zn X B B = blue-chromating
Zn X C C = yellow-chromating
Zn X F F = black-chromating
Zn X TLP TLP= Thick Layer Passivation (is recom-
mended to replace yellow chromating, Zn X C.)
Hot-dip galvanizing tZnO X t = “thermal”
Electroless nickel NiP(%) X Nickel phosphorous shall be specified to ISO 4527
plating (the bracketed figure specifies the phosphorous per-
centage)
Chromating - yel- Yellow- Basic material: Al or Zn
low chromating Cr+6)
CVD coating CVD-TiC X TiC = Titanium carbide
CVD-TiN X TiN = Titanium nitride
CVD-TiCN X TiCN = Titanium carbo nitride
CVD- = other coating type
PVD coating PVD-TiN X TiN = Titanium nitride
PVD-TiCN X TiCN = Titanium carbo nitride
PVD- = other coating type
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9th issue, 2006-05 Page 4 of 5
Coating Designation Explanation
X = Coating
thickness in µm
Burnishing br A f A = burnishing (in one bath)
f = oiling
Pickling AB Pickling in nitric acid + mix acid
AFR Removal of rust in hydrochloric acid (steel blanks)
ACTB Actane® pickling (stainless steel blanks)
Pickling with pas- Gu
sivation
Anodizing Anodizing X
Hard-anodizing Hard-anodizing X
Zinc-phosphating Znph X ¤) *) ¤ Coating thickness can be specified either in µm
Manganese- Mnph X ¤) *) or in g/m2; however, the unit of thickness shall
phosphating Feph X ¤) *) always be stated.
Iron-phosphating
* It is important to inform the supplier of the pur-
Phosphating coat- pose of the phosphate treatment
ings shall be speci- • protection against corrosion, improvement of
fied to EN 12476 adherence of surface coating and adhesive
• improved cold extrusion processing
• reduction of friction
• electrical insulation
as the phosphate layer can take various forms
according to purpose
7 Cross-reference: new and old designations for surface coatings
Designation X indicates coating thickness
Old designation New designation
X AN anodized X
KRO = Al Passivation - yellow chromate yellow-chromating
Chem. Ni X NiP X
Zn = Galvanizing Zn X
Zn VD = Hot-dip galvanizing tZnO X
Zn X Kro = Galvanizing + chromating Zn X C
CVD = “Chemical vapour deposition”, TiN = Titanium nitride CVD-TiN X
Titanium carbide CVD-TiC X
Titanium carbo nitride CVD-TiCN X
PVD = “Physical vapour deposition” Titanium nitride PVD-TiN X
Titanium carbo nitride PVD-TiCN X
Mn phosphate (or Mn-fo) Mnph X
Zn phosphate (or Zn-fo) Znph X
St phosphate (or Fe-fo) Feph X
Burnishing br A f
BE = Pickling AB, AFR or ACTB
Hard-anodizing Hard-anodizing
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9th issue, 2006-05 Page 5 of 5
8 References
ISO 4042, 1999, Fasteners - Electroplated coatings
ISO 4520, 1981 Chromate conversion coatings on electroplated zinc and cadmium coatings.
ISO 4527, 2003 Autocatalytic (electroless) nickel-phosphorus alloy coatings - Specifica-
tions and test methods
EN 1403, 1998, Corrosion protection of metals - Electrodeposited coatings - Method of
specifying general requirements
EN 12329, 2000, Corrosion protection of metals – Electrodepositde coatings of zinc with
supplementary treatment on iron and steel
EN 12476, 2000, Phosphate conversion coatings of metals - Method of specifying require-
ments
DIN 50960-1, 1998, Galvanische und chemische Überzüge, Bezeichnungen und Angaben in
technischen Unterlagen
DIN 50960-2, 2006, Galvanische Überzüge. Zeichnungsangaben
Danfoss documents
(If no date is given the latest issue applies)
500B0286, Design classes and product colours
500B0318, Technical drawing. Specification of galvanic and chemical coatings
500B0401, Case hardening and tempering. Definitions, indications on drawings and specifica-
tion
9 Bibliography
ISO 1456, 2003: Metallic coatings - Electrodeposited coatings of nickel plus chromium and of
copper plus nickel plus chromium.
ISO 1458, 2002: Metallic coatings. Electrodeposited coatings of nickel.
ISO 2081, 1986: Metallic coatings - Electroplated coatings of zinc on iron or steel.
ISO 2093, 1986: Electroplated coatings of tin - Specification and test methods.
ISO 3892, 2000 Conversion coatings on metallic materials - Determination of coating mass per
unit area - Gravimetric methods.
ISO 4042, 1999: Fasteners - Electroplated coatings.
ISO 8992, Fasteners; General requirements for bolts, screws, studs and nuts.
DIN 6773, 2001 Wärmebehandlung von Eisenwerkstoffen - Darstellung und Angaben wärme-
behandelter Teile in Zeichnungen.
DIN 50965, 2000, Galvanische Überzüge - Zinnüberzüge auf Eisen- und Kupferwerkstoffen.
EN 12540, 2000 Corrosion protection of metals - Electrodeposited coatings of nickel, nickel
plus chromium, copper plus nickel and copper plus nickel plus chromium.
Danfoss “TRIBKO”-catalogue, December 1987.
Changes in relation to previous issue:
New issue of DIN 50960-2.
