ISO 19259:2021

FINAL
INTERNATIONAL ISO/FDIS
DRAFT
STANDARD 19259
ISO/TC 123/SC 7
Plain bearings — Bearings with
Secretariat: JISC
embedded solid lubricants
Voting begins on:
2021­06­18
Paliers lisses — Paliers avec lubrifiants solide incorporé
Voting terminates on:
2021­08­13
RECIPIENTS OF THIS DRAFT ARE INVITED TO
SUBMIT, WITH THEIR COMMENTS, NOTIFICATION
OF ANY RELEVANT PATENT RIGHTS OF WHICH
THEY ARE AWARE AND TO PROVIDE SUPPOR TING
DOCUMENTATION.
IN ADDITION TO THEIR EVALUATION AS
Reference number
BEING ACCEPTABLE FOR INDUSTRIAL, TECHNO­
ISO/FDIS 19259:2021(E)
LOGICAL, COMMERCIAL AND USER PURPOSES,
DRAFT INTERNATIONAL STANDARDS MAY ON
OCCASION HAVE TO BE CONSIDERED IN THE
LIGHT OF THEIR POTENTIAL TO BECOME STAN­
DARDS TO WHICH REFERENCE MAY BE MADE IN
©
NATIONAL REGULATIONS. ISO 2021

---------------------- Page: 1 ----------------------
ISO/FDIS 19259:2021(E)

COPYRIGHT PROTECTED DOCUMENT
© ISO 2021
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
CH­1214 Vernier, Geneva
Phone: +41 22 749 01 11
Email: copyright@iso.org
Website: www.iso.org
Published in Switzerland
ii © ISO 2021 – All rights reserved

---------------------- Page: 2 ----------------------
ISO/FDIS 19259:2021(E)

Contents Page
Foreword .iv
1 Scope . 1
2 Normative references . 1
3 Terms and definitions . 1
4 Characteristics . 1
4.1 Structure . 1
4.2 Friction and wear characteristics . 3
4.3 Applicable field . 3
5 Material . 4
5.1 Metallic base body . 4
5.1.1 General. 4
5.1.2 Copper alloy castings . 4
5.1.3 Grey cast irons . 5
5.2 Solid lubricant. 5
5.3 Combination of metallic base body and solid lubricant . 6
6 Dimensions . 6
7 Assembling . 9
8 Surface finish . 9
Annex A (informative) Guide for selection of a bearing with embedded solid lubricants .11
Annex B (informative) Actual applications of a bearing with embedded solid lubricants .12
Bibliography .13
© ISO 2021 – All rights reserved iii

---------------------- Page: 3 ----------------------
ISO/FDIS 19259:2021(E)

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 non­governmental, 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 by Technical Committee ISO/TC 123, Plain bearings, Subcommittee SC 7,
Special types of plain bearings.
This second edition cancels and replaces the first edition (ISO 19259:2015), of which it constitutes a
minor revision.
The main changes compared to the previous edition are as follows:
— editorial update.
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 2021 – All rights reserved

---------------------- Page: 4 ----------------------
FINAL DRAFT INTERNATIONAL STANDARD ISO/FDIS 19259:2021(E)
Plain bearings — Bearings with embedded solid lubricants
1 Scope
This document specifies a bearing with embedded solid lubricants, which has been widely used as a
solid lubricant bearing.
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 185, Grey cast irons — Classification
3 Terms and definitions
No terms and definitions are listed in this document.
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/
4 Characteristics
4.1 Structure
A bearing with embedded solid lubricants is composed of a metallic base body supporting a load and
a solid lubricant embedded in holes or hollows formed on the surface of the metallic base body giving
lubricity. As to the embedded state of a solid lubricant, there is a plug type and a spiral type (see
Figure 1).
As for hole type, there are “through” or perforated ones and “bottomed” ones (see Figure 2).
This document specifies a type which is most common and has been widely used where a solid lubricant
of a plug type is embedded in through holes. This document also specifies a cylindrical bush and a
flanged bush (see Figure 3).
© ISO 2021 – All rights reserved 1

---------------------- Page: 5 ----------------------
ISO/FDIS 19259:2021(E)

a)  Plug type b)  Spiral type
Figure 1 — Embedded state of solid lubricants on cylindrical bush
a)  Through hole type b)  Bottomed hole type
Key
1 metallic base body
2 hole
3 solid lubricant plug
Figure 2 — Structure of cross section on a bearing with embedded solid lubricants
a)  Cylindrical bush b)  Flanged bush
Figure 3 — Overview of a bearing with embedded solid lubricants (plug type)
2 © ISO 2021 – All rights reserved

---------------------- Page: 6 ----------------------
ISO/FDIS 19259:2021(E)

4.2 Friction and wear characteristics
A bearing with embedded solid lubricants falls under the category of a solid lubricant bearing among
self-lubricating bearings. In the solid lubricant bearings, there is a solid type, a coated type, a dispersed
type, and an embedded type.
A solid type is such where a solid lubricant powder is solidified using pitch, resin or the like as a binder.
A coated type is such where a solid lubricant film is formed on a sliding surface by chemical or physical
means such as coating, baking, chemical reaction, or the like.
A dispersed type is such where a solid lubricant powder (fine particles) is dispersed into sintered metal
matrix or the like.
An embedded type is such as mentioned above where holes or hollows are formed on a sliding surface
of a metallic base body and solid lubricants are embedded therein and, since the load is supported by a
metallic base body, this type has excellent load carrying capacity.
The embedded solid lubricant supplies solid lubricant to the sliding surface and, when it slides on
the mating member, the solid lubricant is properly drawn out and spread over both sliding surfaces
whereupon a solid lubricant film is formed.
Further, even when the film is broken, the embedded solid lubricant is drawn out by friction onto the
sliding surfaces, so it repairs the film on the sliding surfaces whereby the lubrication is made possible
for long periods and long life is achieved (see Figure 4).
Since the types of metallic base body and solid lubricant can be appropriately selected depending upon
the operating conditions, a wide range of applications is possible. Moreover, bearings ranging from
small to large sizes can be manufactured.
Key
1 metallic base body
2 mating member
3 embedded solid lubricant
4 solid lubricant film
A sliding direction
Figure 4 — Lubricating mechanism of a bearing with embedded solid lubricants
4.3 Applicable field
The bearing can be used for rotational motion, reciprocating motion, oscillating motion, and frequent
start/stop cycles. The bearing is also used in such a
...