ISO 23055:2020

INTERNATIONAL ISO
STANDARD 23055
First edition
2020-01
Ships and marine technology — Design
requirements for international ballast
water transfer connection flange
Reference number
©
ISO 2020
© ISO 2020
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ii © ISO 2020 – All rights reserved

Contents Page
Foreword .iv
Introduction .v
1 Scope . 1
2 Normative references . 1
3 Terms and definitions . 1
4 Abbreviated terms . 1
5 Materials and equipment . 1
5.1 General . 1
5.2 Pressure rating . 2
5.3 Non-metallic materials . 2
5.4 Accessories . 2
6 Workmanship . 2
7 Dimensions . 2
8 Marking . 3
9 Quality assurance . 4
10 Ordering information . 4
11 Installation . 4
Annex A (normative) Design of a flange for ballast water transfer systems of larger capacity .5
Annex B (informative) Alternate design of flange bolt hole arrangement . 6
Bibliography . 7
Foreword
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This document was prepared by Technical Committee ISO/TC 8, Ships and marine technology,
Subcommittee SC 3, Piping and machinery.
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iv © ISO 2020 – All rights reserved

Introduction
It is recognized that transfer of ballast water between a ship and a shore-side facility, or another ship,
can be necessary to manage ballast water treatment.
In order for ships and shore facilities to connect the ballast water transfer piping in an efficient
manner, a standardized interface flange is necessary. This type of connection would be similar to the
international fire main ship/shore connection required by the International Convention for the Safety
of Life at Sea (SOLAS).
The need for a standardized international flange for ballast water transfer systems has been presented
to the International Maritime Organization (IMO) Marine Environmental Protection Committee
(MEPC). A standard transfer connection will help enable efficient transfer of ballast water between
ships and facilities in accordance with the Guidel
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