Notesale: Turn your study into money

Document Preview

Extracts from the notes are below, to see the PDF you'll receive please use the links above

---

FINAL
DRAFT

ISO/TC 35/SC 12
Secretariat: BSI
Voting begins on:
2011-11-24
Voting terminates on:
2012-01-24

INTERNATIONAL
STANDARD

ISO/FDIS
8503-2

Preparation of steel substrates before
application of paints and related
products — Surface roughness
characteristics of blast-cleaned steel
substrates —
Part 2:
Method for the grading of surface
profile of abrasive blast-cleaned steel —
Comparator procedure
Préparation des subjectiles d’acier avant application de peintures et
de produits assimilés — Caractéristiques de rugosité des subjectiles
d’acier décapés —
Partie 2: Méthode de classification d’un profil de surface en acier
décapée par projection d’abrasif — Utilisation des comparateurs visotactile ISO

RECIPIENTS OF THIS DRAFT ARE INVITED TO
SUBMIT, WITH THEIR COMMENTS, NOTIFICATION
OF ANY RELEVANT PATENT RIGHTS OF WHICH
THEY ARE AWARE AND TO PROVIDE SUPPOR­
TING DOCUMENTATION
...


Please see the administrative notes on page iii

Reference number
ISO/FDIS 8503-2:2011(E)

© ISO 2011

ISO/FDIS 8503-2:2011(E)

Copyright notice
This ISO document is a Draft International Standard and is copyright-protected by ISO
...

Requests for permission to reproduce should be addressed to either ISO at the address below or ISO’s
member body in the country of the requester
...
+ 41 22 749 01 11
Fax + 41 22 749 09 47
E-mail copyright@iso
...
iso
...

Violators may be prosecuted
...
The final draft
was established on the basis of comments received during a parallel enquiry on the draft
...

Positive votes shall not be accompanied by comments
...


© ISO 2011 – All rights reserved

iii

ISO/FDIS 8503-2:2011(E)

Contents

Page

Foreword
...
vi
1

Scope
...
1

3

Terms and definitions
...
2

5

Apparatus
...
2

7

Procedure
...
3

iv



© ISO 2011 – All rights reserved

ISO/FDIS 8503-2:2011(E)

Foreword
ISO (the International Organization for Standardization) is a worldwide federation of national standards bodies
(ISO member bodies)
...
Each member body interested in a subject for which a technical committee has been
established has the right to be represented on that committee
...
ISO collaborates closely with the International
Electrotechnical Commission (IEC) on all matters of electrotechnical standardization
...

The main task of technical committees is to prepare International Standards
...
Publication as an
International Standard requires approval by at least 75 % of the member bodies casting a vote
...
ISO shall not be held responsible for identifying any or all such patent rights
...

This second edition cancels and replaces the first edition (ISO  8503‑2:1988), which has been technically
revised
...
The principal factors that are known to influence
this performance are:
a) the presence of rust and mill scale;
b) the presence of surface contaminants, including salts, dust, oils and greases;
c) the surface profile
...

These International Standards do not contain provisions for the protective coating systems to be applied to the
steel surface or for the surface quality provisions for specific situations, even though surface quality can have
a direct influence on the choice of protective coating to be applied and on its performance
...

It is necessary for the users of these International Standards to ensure that the qualities specified are:
— compatible and appropriate both for the environmental conditions to which the steel is exposed and for the
protective coating system to be used;
— within the capability of the cleaning procedure specified
...

Irrespective of the procedures and the type of abrasive used for the preparation of steel substrates, the surface
after blast-cleaning consists of random irregularities with peaks and valleys that are not easily characterized
...
Thus, it is intended that the profile be identified as either dimpled (where shot abrasives
are used) or angular (where grit abrasives are used) and that it be graded as “fine”, “medium” or “coarse”, each
grade being defined by the limits specified in ISO 8503‑1
...

Particular attention, however, is drawn to the fact that the grades “fine”, “medium” and “coarse” represent
different ranges in terms of roughness parameters, dependent upon whether these grades are applied to shot
abrasive or grit abrasive blast-cleaned surfaces
...
Where surface profile is particularly important,
both the grade of the surface profile (“fine”, “medium” or “coarse”) and the type of abrasive which is to be used
are to be specified
...

The method uses ISO surface profile comparators for assessing, on site, the roughness of surfaces before the
application of paint or other protective treatments
...


The method is applicable to steel surfaces which have been blast-cleaned by use of either shot abrasives or
grit abrasives, but is only applicable to grades Sa 2½ and Sa 3 of ISO 8501‑1 where the entire surface under
test shows an overall blast-cleaned appearance
...


2 Normative references
The following referenced documents are indispensable for the application of this document
...
For undated references, the latest edition of the referenced document
(including any amendments) applies
...

© ISO 2011 – All rights reserved



1

ISO/FDIS 8503-2:2011(E)

4 Principle
The surface profile of the test surface is compared by visual or tactile means with the profile of each of the
segments of a calibrated ISO surface profile comparator to identify the two segments between the profiles of
which the test surface lies
...


5 Apparatus
5
...

NOTE
In ISO 8503‑1, two comparators are specified: one with surface profiles corresponding to surfaces which have
been blast-cleaned using grit abrasives (reference comparator G) and one with surface profiles corresponding to surfaces
which have been blast-cleaned using metallic shot abrasives (reference comparator S)
...


If a mixture of shot and grit abrasives is used to blast-clean a substrate, the grit-abrasive reference comparator
G should preferably be used
...
Hence, the relevant comparator should be
selected for these abrasives (described in ISO 8504‑2)
...
2

Hand lens, with magnification not exceeding ×7
...
If any wear is detected, the comparator shall be discarded or, if
appropriate, re-calibrated (see ISO 8503‑1:2012, Clause 7)
...
If a segment of a used comparator, when compared with
the equivalent segment of an unused comparator, yields a different grading assessment (see this part of
ISO 8503) of a surface profile, the used comparator should be discarded or re-calibrated
...
1 Remove all loose dust and debris from the test surface
...
, are not considered part of the primary profile and should be removed by grinding prior to abrasive
blast-cleaning
...
2 Select the appropriate surface profile comparator (5
...
Compare,
in turn, the test surface with the four segments of the comparator, using the hand lens (5
...
If the hand lens is used, place it so that the test surface is viewed simultaneously with a segment of the
comparator
...


2



© ISO 2011 – All rights reserved

ISO/FDIS 8503-2:2011(E)

Table 1 — Limits of profile grades
Fine

Profiles equal to segment 1 and up to
but excluding segment 2

Medium

Profiles equal to segment 2 and up to
but excluding segment 3

Coarse

Profiles equal to segment 3 and up to
but excluding segment 4

NOTE
If visual assessment proves difficult, tactile assessment provides a useful guide
...


7
...

7
...
If any profile is assessed as below the lower limit for
the “fine” grading, report the grading as “finer than fine”
...

7
...

NOTE 1 If the condition of the steel is such that it is necessary to adopt the procedure described in 7
...

NOTE 2 When surfaces are subject to re-blasting operations, the initial profile can override the secondary profile
normally expected from the type of abrasive and conditions used in the re-blasting operations
...
6 In cases of dispute, a representative sample of the surface shall be provided and measured as described
in ISO 8503‑3 or ISO 8503‑4
...


8 Test report
The test report shall contain at least the following information:
a) a reference to this part of ISO 8503, i
...
ISO 8503-2:2012;
b) all information necessary for the identification of the steel substrate(s) tested;

1) Insert “fine”, “medium” or “coarse”, as appropriate
...
This information shall be derived
from parts of ISO 8501, ISO 8503 and ISO 8504 or similar standards or, where appropriate, shall be the
subject of agreement between the interested parties:
1) when and where the assessment of grading is to be carried out (i
...
the frequency of assessments as
blast-cleaning proceeds and the nominal distance between individual assessments);
2) wherever possible, whether shot or grit abrasive (or a mixture of shot and grit abrasives) is to be used
for the blast-cleaning procedure(s);
3) the required grading of the blast-cleaned substrates in terms of “fine”, “medium” or “coarse”;
4) if required, the type of comparator to be used, i
...
comparator G or comparator S;
d) where possible, the rust grade(s) of the steel surface prior to abrasive blast-cleaning , the method of
abrasive blast-cleaning used with reference to ISO 8504‑2 and a description of the abrasive used;
NOTE
The rust grade of the steel is indicative of the “primary” profile of the surface and hence this affects the profile
of the cleaned substrate
...


e) the result of the test (including the number of assessments made), identification of the reference comparator
used and, if direct assessment was not possible, a statement as detailed in 7
...
6), the method of measurement used and the profile value determined;

g) any deviation from the procedure specified;
h) any unusual features (anomalies) observed during the test;
i)

the name of the operator;

j)

the date of the test
...
220

---