BS/EN 10152-2017 pdf download.Electrolytically zinc coated cold rolled steel flat products for cold forming Technical delivery conditions.
6.11 Surface treatment (surface protection)
At the time of enquiry and order, one of the surface treatment conditions listed in Table 3 shall be agreed.
Surface treatment can reduce the risk of corrosion occurring during transport and storage, which is mainly due to humidity and gives rise to wet storage stain (white rust). The phosphated, chemically sealed and oiled treatment condition normally offers the best corrosion protection. Since this type of protection is, however, not permanent the transport and storage conditions shall be selected to suit the material concerned.
A surface treatment also improves the adherence and protective effect of a coating applied by the processor who shall ensure that pretreatment and coating systems are compatible with each other.
NOTE 1 Discoloration as a result of chemical treatment does not impair further processing.
Chemically sealed or passivated material is not recommended for products which will subsequently be phosphated.
Phosphating in conjunction with a suitable lubricating agent may improve workability.
The application of a sealed (S) surface treatment, with a transparent organic film of about lg/m!, will offer protection against corrosion and fingerprints. It may Improve the sliding characteristics during forming and can be used as a priming coat for subsequent varnishing.
The products are only supplied without surface treatment (U) if expressively desired by the purchaser on his own responsibility.
NOTE 2 In such cases. corrosion damage to the product can occur even when stored for short periods or during transport. Untreated products are also susceptible to fretting corrosion and are easily scratched.
In the case of oiled surfaces, it shall be possible to remove the oil layer with suitable detergents not attacking the zinc coating. It is assumed that the processor has all the equipment necessary for degreasing the products.
6.12.2 Painting
Zinc coated steel is a suitable base [or paint, but the first treatment may be different from those used for uncoated steel. Pre-treatment primers, chemical conversion coatings and primers specially formulated for direct application to zinc surfaces are all appropriate first treatments for electrolytically zinc coated steel.
In drawing up a surface preparation and painting schedule, consideration should be given by the purchaser as to whether the material should be supplied chemically passivated or phosphated and/or oiled (see also
6.12.3 Forming
Electrolytic zinc coatings are usually tightly adherent even when used for difficult formings. However, powdering can occur if the product is overformed or coined during fabrication. Care should be taken to ensure that the speed of forming and the clearance oldies is carefully controlled.
6.13 Mass, tolerances on dimensions and shape
6.13.1 The product mass shall be calculated taking the density of the steel as 7,85 kg/dm and the density of
the zinc coating as 7,1 kg/dm3.
6.13.2 For the tolerances on dimensions and shape EN 10131 applIes.
When hot rolled products are supplied, the tolerances shall be in accordance with EN 10051. The application of other dimensional standards shall be specially agreed at the time of enquiry and order.
7 Inspection
7.1 Types of inspection and inspection documents
7.1.1 Unless otherwise specified at the time of enquiry and order (see 7.1.2 and 7.1.3), the products shall be delivered with non-specific inspection without inspection document.
7.1.2 Specific testing in accordance with the requirements in 7.2 to 7.6 may be specified at the time of enquiry and order.
By agreement at the time of enquiry and order, the manufacturer may determine the tensile properties by calculation in accordance with an approved method.
Specific testing may not be specified either for the product analysis or for the surface finish. However, if so agreed at the time of enquiry and order, the manufacturer shall supply a certificate of compliance with the order.BS/EN 10152-2017 pdf download.