ISO 13755:2020

Ships and marine technology — Ship's mooring and towing fittings — Steel rollers

This document specifies the types, nominal sizes, dimensions and materials, as well as construction, manufacturing and marking requirements, for steel rollers installed to lead the mooring rope of a ship.

Navires et technologie maritime — Corps-morts et ferrures de remorquage de navires — Rouleaux en acier

General Information

• Status: Published
• Publication Date: 27-Aug-2020
• ICS: 47.020.50 - Deck equipment and installations
• Technical Committee: ISO/TC 8/SC 4 - Outfitting and deck machinery
• Drafting Committee: ISO/TC 8/SC 4/WG 4 - Ship's mooring and towing fittings
• Current Stage: 9020 - International Standard under periodical review
• Start Date: 15-Jul-2025
• Completion Date: 15-Jul-2025

Relations

• Consolidated By: ISO 9073-14:2023 - Nonwovens — Test methods — Part 14: Coverstock wetback (simulated urine)
• Effective Date: 06-Jun-2022
• Revises: ISO 13755:2012 - Ships and marine technology — Ship's mooring and towing fittings — Steel rollers
• Effective Date: 30-Sep-2017

Standards Content (Sample)

INTERNATIONAL ISO
STANDARD 13755
Second edition
2020-08
Ships and marine technology —
Ship's mooring and towing fittings —
Steel rollers
Navires et technologie maritime — Corps-morts et ferrures de
remorquage de navires — Rouleaux en acier
Reference number
©
ISO 2020
© ISO 2020
All rights reserved. Unless otherwise specified, or required in the context of its implementation, no part of this publication may
be reproduced or utilized otherwise in any form or by any means, electronic or mechanical, including photocopying, or posting
on the internet or an intranet, without prior written permission. Permission can be requested from either ISO at the address
below or ISO’s member body in the country of the requester.
ISO copyright office
CP 401 • Ch. de Blandonnet 8
CH-1214 Vernier, Geneva
Phone: [phone]
Email: [e-mail]
Website: www.iso.org
Published in Switzerland
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 Classification . 1
4.1 Type . 1
4.2 Nominal sizes . 1
5 Dimensions . 2
6 Materials . 2
7 Construction . 2
8 Manufacturing and inspection . 2
9 Marking . 2
Annex A (normative) Basis for strength assessment of steel rollers .16
Bibliography .18
Foreword
ISO (the International Organization for Standardization) is a worldwide federation of national standards
bodies (ISO member bodies). The work of preparing International Standards is normally carried out
through ISO technical committees. Each member body interested in a subject for which a technical
committee has been established has the right to be represented on that committee. International
organizations, governmental and non-governmental, in liaison with ISO, also take part in the work.
ISO collaborates closely with the International Electrotechnical Commission (IEC) on all matters of
electrotechnical standardization.
The procedures used to develop this document and those intended for its further maintenance are
described in the ISO/IEC Directives, Part 1. In particular, the different approval criteria needed for the
different types of ISO documents should be noted. This document was drafted in accordance with the
editorial rules of the ISO/IEC Directives, Part 2 (see www .iso .org/ directives).
Attention is drawn to the possibility that some of the elements of this document may be the subject of
patent rights. ISO shall not be held responsible for identifying any or all such patent rights. Details of
any patent rights identified during the development of the document will be in the Introduction and/or
on the ISO list of patent declarations received (see www .iso .org/ patents).
Any trade name used in this document is information given for the convenience of users and does not
constitute an endorsement.
For an explanation of the voluntary nature of standards, the meaning of ISO specific terms and
expressions related to conformity assessment, as well as information about ISO's adherence to
the World Trade Organization (WTO) principles in the Technical Barriers to Trade (TBT), see
www .iso .org/ iso/ foreword .html.
This document was prepared Technical Committee ISO/TC 8, Ships and marine technology, Subcommittee
SC 4, Outfitting and deck machinery.
This second edition cancels and replaces the first edition (ISO 13755:2012), which has been editorially
and technically revised.
The main changes compared to the previous edition are as follows:
— technical guidelines have been added in 7.3 and 7.4;
— the definition of SWL (3.1) has been reworded;
— the object line, extension line, dimension line and welding volume in Figures 1, 4 and 6 have been
amended;
— the column titles in Table 1 have been amended.
Any feedback or questions on this document should be directed to the user’s national standards body. A
complete listing of these bodies can be found at www .iso .org/ members .html.
iv © ISO 2020 – All rights reserved

Introduction
The steel roller is a type of ship’s mooring fitting installed on board, to lead the mooring rope from the
ship’s inboard to outboard as a shipside roller fairlead, and to change the direction of the ropes as a
pedestal fairlead.
INTERNATIONAL STANDARD ISO 13755:2020(E)
Ships and marine technology — Ship's mooring and towing
fittings — Steel rollers
1 Scope
This document specifies the types, nominal sizes, dimensions and materials, as well as construction,
manufacturing and marking requirements, for steel rollers installed to lead the mooring rope of a ship.
2 Normative references
The following documents are referred to in the text in such a way that some or all of their content
constitutes requirements of this document. For dated references, only the edition cited applies. For
undated references, the latest edition of the referenced document (including any amendments) applies.
ISO 13767, Ships and marine technology — Ship’s mooring and towing fittings — Shipside roller fairleads
ISO 13776, Ships and marine technology — Ship’s mooring and towing fittings — Pedestal fairleads
IMO Circular MSC/Circ.1175, Guidance on shipboard towing and mooring equipment
3 Terms and definitions
For the purposes of this document, the following terms and definitions apply.
ISO and IEC maintain terminological databases for use in standardization at the following addresses:
— ISO Online browsing platform: available at https:// www .iso .org/ obp
— IEC Electropedia: available at http:// www .electropedia .org/
3.1
safe working load
SWL
safe load limit (maximum permissible load) of the fittings used for mooring and towing
4 Classification
4.1 Type
Depending on the construction, steel rollers shall be classified as belonging to one of the following
three types:
a) Type A: made of steel casting without upper dust cover;
b) Type B: made of steel casting with upper dust cover;
c) Type C: made of steel plate with dust cover.
4.2 Nominal sizes
The nominal sizes, D , of steel rollers are denoted by reference to the outside diameter of the roller, in
n
millimetres, from a basic series of preferred numbers.
The nominal sizes are: 150, 200, 250, 300, 350, 400, 450 and 500.
5 Dimensions
The steel rollers shall have dimensions and particulars in accordance with Tables 1, 2, 3, 4, 5, 6, 7 and 8,
and Figures 1, 2, 3, 4, 5, 6, 7 and 8.
6 Materials
The following materials shall be used for manufacturing the different components of steel rollers:
a) roller: steel casting having a yield point of not less than 205 N/mm , or steel plates having a yield
point of not less than 235 N/mm ;
b) axle: weldable steel casting having a yield point of not less than 350 N/mm or equivalent;
c) bush: brass, bronze or equivalent.
7 Construction
7.1 The rollers of the steel rollers (Type C) shall be constructed from steel tubes or formed from plate.
7.2 The foundation of the steel rollers shall be determined by the manufacturer in accordance
with ISO 13767 and ISO 13776. The foundation and welding connections shall guarantee a reliable
transmission of the maximum loading of the steel rollers to the hull construction without any plastic
deformation or cracks.
7.3 The selection of ship’s mooring fittings and mooring lines should take into account the diameter, D,
of surfaces of mooring fittings that are in contact with the mooring line diameter, d, (D/d ratio) to reduce
or mitigate bend loss of strength.
7.4 The tensile strength of a mooring rope may be reduced depending on the bend radius (D/d ratio)
through the mooring fittings, in accordance with the rope manufacturer’s guidelines.
8 Manufacturing and inspection
8.1 All surfaces of the steel rollers, including welded surfaces, shall be free from any visible flaws or
imperfections.
8.2 All surfaces in contact with the ropes shall be free from surface roughness or irregularities likely to
cause damage to the ropes by abrasion.
8.3 The steel rollers shall be coated externally with an anti-corrosion protective finish.
8.4 All rotating parts shall be greased.
9 Marking
9.1 The safe working load (SWL) for the intended use of the steel rollers shall be noted in the towing
and mooring plan available on board for the guidance of the shipmaster as specified in IMO circular MSC/
Circ.1175.
9.2 The actual SWL on board shall be determined by considering the foundation and under deck
reinforcement, and it shall be marked on the towing and mooring plan. The actual SWL shall not be over
the SWL indicated in this document.
2 © ISO 2020 – All rights reserved

9.3 The steel rollers shall be clearly marked on their seat or foundation with their SWL by weld bead
or equivalent. The SWL shall be expressed in tonnes (symbol 't') and be placed so that it is not obscured
during operation of the fitting.
EXAMPLE SWL XXX t
Dimensions in millimetres
a) Type A
b) Type B
Key
1 roller
2 axle
3 bush
4 dust cover to apply on type B only
5 N-M6 bolt
a
Drain hole.
Figure 1 — Assembly of steel rollers for nominal sizes 150, 200 and 250 (type A and type B)
4 © ISO 2020 – All rights reserved

Dimensions in millimetres
a)  Type A
b)  Type B
Key
1 roller 3 bush 5 N-M6 bolt
a
2 axle 4 dust cover to apply on type B only Drain hole.
Figure 2 — Assembly of steel rollers for nominal sizes 300 and above (type A and type B)
Dimensions in millimetres
Key
1 roller 2 dust cover to apply on type B only
Figure 3 — Detail of steel rollers for nominal sizes 150, 200 and 250 (type A and type B)
Dimensions in millimetres
Key
1 roller 2 dust cover to apply on type B only
Figure 4 — Detail of steel rollers for nominal sizes 300 and above (type A and type B)
6 © ISO 2020 – All rights reserved

Table 1 — Dimensions of steel rollers for type A and type B
Dimensions in millimetres
Nom-
inal D D D
2 3 5
D D R R R R H H H H H e
1 4 1 2 3 4 1 2 3 4
size +2/0 +2/0 H7
D
n
150 150 230 216 110 90 30 52 15 11 137 25 84 44,7 43,38 37,7
200 200 300 280 145 115 40 66 20 13 157 30 99 59,2 35,46 46,3
250 250 370 340 165 135 50 80 25 15 177 32 105 73,5 28,33 55,0
300 300 430 400 190 150 55 87 30 16 197 33 125 82,6 32,62 60,8
350 350 490 460 210 167 55 89 30 17 217 33 140 83,7 49,06 63,7
400 400 560 520 225 177 63 99 30 18 237 43 150 91,8 52,0 72,2
450 450 620 590 245 190 63 101 30 19 257 43 162 92,5 67,07 74,8
500 500 680 660 260 205 63 103 30 20 277 43 180 93,0 82,94 77,6
Table 2 — Dimensions (continued) and SWL of steel rollers for type A and type B
Dimensions in millimetres
b
SWL Calculated
c
weight
Nominal Set Welding
a
θ = 90° θ = 0°
kg/set
size h h h screw T T N leg length
1 2 1
D s z
Type Type
n 1
kN t kN t
A B
150 5 35 25 M6 22 — 6 8 265 27 186 19 23 24
200 5 38 35 M6 26 — 6 10 441 45 314 32 42 43
250 6 40 35 M8 30 — 6 11 579 59 412 42 77 80
300 7 45 40 M8 32 29 8 12 726 74 510 52 109 112
350 7 50 45 M8 34 29 8 15 1 040 106 736 75 154 160
400 7 53 49 M8 36 30 12 17 1 246 127 883 90 207 215
450 7 57 53 M8 38 32 12 20 1 599 163 1 128 115 275 286
500 7 65 60 M8 40 34 12 23 1 942 198 1 373 140 360 374
a
θ
...