Technical noteSynchronous generators for steam and gas turbinesPre-engineered generators - Painting systems

ABB generators are designed for a long operating life in all types of environment - from clean, heated, indoor locations to open deck installations in offshore applications. AMS pre-engineered generators can be provided with two differ-ent painting systems, C3 and C5-M, to cope with different installation environments. To assure high quality corrosion protection, ABB only works with large, recognized paint sup-pliers and ensures that the personnel who do the painting are fully trained and competent.

Corrosivity categories ISO standard 12944-21 defines corrosivity categories accord-ing to the mass loss of unpainted steel or zinc exposed for one year at the site in question. In the absence of such fig-ures, an estimation of the corrosivity category may be made using the table below, which is applicable to the temperate climate region.

1ISO 12944-2, Paints and varnishes - Corrosion protection of steel structures

by protective paint systems - Part 2 Classification of environment

Corrosivity categories Outdoor atmospheres Indoor atmospheres

C3 Medium Atmospheres with low salinity or moderate pollution. Urban and lightly industrialized areas. Areas with some coastal influence.

Spaces with moderate frequency of con-densation and some pollution from produc-tion processes, e.g. food processing plants, breweries, diaries, laundries.

C5-M Very high(Marine atmosphere)

Atmospheres with high humidity and high sa-linity. Coastal and offshore splash zone areas

Spaces with almost permanent condensation and with very high salinity

ABB is a leading supplier of synchronous turbine-driven generators to power utili-ties, paper mills, sugar plants, oil and gas installations, and many other sectors. We have been manufacturing generators for more than 120 years and have exten-sive application experience with tens of thousands of installations all over the world. ABB offers reliable and efficient power generation with worldwide support.

ABB standard painting cycles ABB considers durability high (H) as standard for each painting cycle. The C3 painting system is the standard for AMS Basic generators.

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Environment ABB painting Pretreatment Painting3

system

Urban and industrial indoor and outdoor atmospheres with moderate corrosivity. Coastal areas withlow salinity.

Blast-cleaningSa 2½ . ISO 8501

Zn-phospatizing(certain sheet metal parts)

2-component epoxy primer 120-140 mm , 1-2 coatsAcrylic topcoat 40-60 mm, 1 coatTotal dry film thickness 180 mm

Epoxy based powder primer 60-80 mm, 1 coat2-component epoxy primer 120-140 mm, 1-2 coatsAcrylic topcoat 40-60 mm, 1 coatTotal dry film thickness 180 mm

C3

Atmospheres with very high salinity and with almost permanent conden-sation. Coastal and offshore splash zone areas.

Blast-cleaningSa 2½ . ISO 8501

2-comp. zinc rich epoxy primer 40-60 mm, 1 coat2-component epoxy primer 160-220 mm, 2-3 coatsAcrylic topcoat 60 mm, 1 coatTotal dry film thickness 320 mm

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In cases where the specified color is not available, a polyurethane top coat will be used. This applies only to special colors. 3 A reduced painting system is used inside the machine

Surface treatment proceduresSplatter and weld slag are removed and surface defects are repaired to preparation grade P3 according to ISO 8501-32. All steel surfaces to be painted are degreased and blast cleaned to Sa 2½ accord-ing to ISO 8501-1:19883. (A special process is utilized for powder coated parts). Edges and areas hard to reach by spraying are primed using a brush, after which primer is sprayed on all parts.

When using zinc rich paint, overcoating with intermediate paint is done immediately after the minimum overcoating interval time of the paint has elapsed, in order to protect the surface from zinc corrorion products (white rust). Surface preparation and painting are carried out in indoor paint shops in a controlled environment. After the paint is cured, the parts are transported to the machine shop and assem-bled into the complete machine. Before application of further coats of paint, the surfaces are roughened and washed to ensure good adhesion between the paint layers. Painting is then completed.

2 ISO 8501-3 Preparation of steel substrates before application of paints and related products - Visual assessment of surface cleanliness; Part 3 Preparation grades of welds, cut edges and other areas with surface imperfections.3 ISO 8501-1:1988 Preparation of steel substrates before application of paints and related products - Visual assessment of surface cleanliness; Part 1 Rust grades and preparation grades of uncoated steel substrates and steel substrates after overall removal of previous coatings, also known as SS 05 59 00.

Standard top coat color is RAL 7032:

The final color can be changed on specific customer request as an option. In this case the color needs to be specified with valid RAL code or NCS code in the purchase order.

RAL 7032

C5-M

We reserve the right to make technical changes or modify the contents of this

document without prior notice. With regard to purchase orders, the agreed

particulars shall prevail. ABB Ltd does not accept any responsibility whatso-

ever for potential errors or possible lack of information in this document.

We reserve all rights in this document and in the subject matter and illustra-

tions contained herein. Any reproduction, disclosure to third parties or utiliza-

tion of its contents - in whole or in part- is forbidden without prior written

consent of ABB Ltd.

© Copyright 2012 ABB. All Rights Reserved

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