Submission of Information on ALTERNATIVES (NON-CONFIDENTIAL)
Submission of information on
Template
for third party submission of information on alternatives for
Applications for Authorisation
non-confidential
Legal name of submitter(s): B. E. Wedge Holdings Limited
Table of CONTENTS
1. alternative ID and properties 3
2. Technical feasibility 3
3. Economic feasibility 3
4. Hazards and risks of the alternative 3
5. Availability 3
6. Conclusion on suitability and availability of the Alternative 3
7. other comments 4
References 4
APPENDIXES 4
1. alternative ID and properties
See alternatives listed in the Analysis of Alternatives (AoA) under consultation 0032-5
2. Technical feasibility
We support the results presented in the AoA. In particular, we support the conclusions drawn in section 7.1.2.2.3. for ‘General Engineering’ which states that Cr (III)-based alternatives are of ‘low maturity in the sector’ and, when evaluating corrosion resistance, states ‘When tested on Zn-coated steels…the corrosion performance is sufficient. For galvanized steel sheets, white rust appearance issues were experienced when the fresh material is exposed to severe environmental conditions during logistical chains’.
3. Economic feasibility
We support the results presented in the AoA.
4. Hazards and risks of the alternative
We support the results presented in the AoA.
5. Availability
We support the results presented in the AoA.
6. Conclusion on suitability and availability of the Alternative
Our original experience with alternatives to chromium trioxide based materials used to address the problem of white rust after galvanizing goes back many years and our initial experiments with trivalent product were in the 1990’s.
Since then we have experimented with alternatives from a number of different suppliers and these continue to date. Unfortunately, we continue to find that the claims made by the prospective suppliers are not fulfilled in practice. Although we are a substantial galvanizing business, we are not chemical experts and depend upon the information and technical advice provided by our suppliers. The alternatives that have been offered to us have been based on trivalent chrome and other substitutes for hexavalent chrome. These products have been used by us as specified within the technical information that they provide during the test periods.
Because galvanized products are frequently exposed to external conditions immediately after galvanizing, in transit and erection etc, they are particularly vulnerable to attack on the zinc surface before the naturally weathered condition is developed. This is particularly caused by rainfall and also very severely, in low dew-point conditions, when aggressive white rust events are regularly seen. It is in this context that we find the alternatives offered do not consistently provide adequate protection.
7. other comments
There is adequate evidence that the galvanized product after passivation in a conventional hexavalent chrome based solutions is not contaminated with hexavalent chrome after processing or in service. Over many years tests within our operations consistently demonstrate that emissions in process are well below control limits. We have no record of health problems within our workforce over decades of use of this type of process.
References
APPENDIXES
[0032-5] [alternatives to chromium trioxide mixtures as temporary corrosion inhibitors to avoid ‘white rust’ on general galvanized articles] [6 October 2015]
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