CLASS PROGRAMME
Type approval
DNVGL-CP-0081
Edition February 2016
Synthetic bearing bushing materials
The electronic pdf version of this document, available free of charge
from http://www.dnvgl.com, is the officially binding version.
DNV GL AS
FOREWORD
DNV GL class programmes contain procedural and technical requirements including acceptance
criteria for obtaining and retaining certificates for objects and organisations related to
classification.
©
DNV GL AS February 2016
Any comments may be sent by e-mail to rules@dnvgl.com
This service document has been prepared based on available knowledge, technology and/or information at the time of issuance of this
document. The use of this document by others than DNV GL is at the user's sole risk. DNV GL does not accept any liability or responsibility
for loss or damages resulting from any use of this document.
Changes - current
CHANGES - CURRENT
This is a new document.
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Changes - current...................................................................................................3
Section 1 General.................................................................................................... 5
1 Introduction.........................................................................................5
2 References........................................................................................... 7
3 Documentation.....................................................................................8
Section 2 General requirements............................................................................ 10
1 Design requirements..........................................................................10
2 Requirements for production and quality control arrangement.......... 10
3 Requirements for material................................................................. 10
4 Wear testing procedure for synthetic rudder bearing bushing
materials...............................................................................................15
5 Approval for use in non-lubrication (dry-running) applications..........16
6 Approval of synthetic propeller shaft bearing materials.................... 16
7 Wear testing procedure for synthetic propeller shaft bearing
materials...............................................................................................17
8 Requirements for marking of product................................................18
Appendix A General scheme for type testing........................................................ 19
1 All surface pressures – entry of type test results.............................. 19
2
2 All surface pressures – up to 5.5 N/mm - entry of type test
results...................................................................................................20
2
3 All surface pressures – above 5.5 N/mm and up to max. 10 N/
2
mm - entry of type test results...........................................................22
Changes – historic................................................................................................ 24
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Contents
CONTENTS
Section 1
SECTION 1 GENERAL
1 Introduction
1.1 Objective
The objective of this class programme (CP) is to give a description of the type approval (TA) scheme for
synthetic bushing materials for rudder bearings and propeller shafts.
The general requirements for obtaining DNV GL type approval certificate is given in class programme DNVGL
CP 0338 Type approval scheme.
The production site may be qualified and certified through the approval of manufacturer (AoM) scheme in
accordance with DNVGL CP 0421.
The procedures and requirements described in this CP are applicable for obtaining TA certificate based on
requirements given in the Society's rules and standards, e.g.:
1)
For synthetic rudder bearing bushing materials:
— DNV GL rules for classification - ships, RU SHIP Pt.3 Ch.14
2)
For synthetic propeller shaft bearing materials:
— DNV GL rules for classification - ships, RU SHIP Pt.4 Ch.4.
Guidance note:
This class programme is not applicable for obtaining EU Marine Equipment Directive (MED) certificates. Visit www.dnvgl.com for
information on MED certification.
---e-n-d---o-f---g-u-i-d-a-n-c-e---n-o-t-e---
1.2 Scope
This CP gives a description of the procedures and requirements related to documentation, design and type
testing applicable for TA of synthetic bushing materials for rudder bearings and propeller shafts.
This CP does not set the design requirements for synthetic bushing materials for rudder bearings and
propeller shafts. TA is based on compliance with design requirements given in the rules and/or other
regulations and standards. The CP describes the applicable requirements and how to document compliance
with the requirements in order to obtain a TA certificate for the equipment. This includes, where relevant,
technical requirements for how the type tests shall be performed.
The type approval certificate will cover one grade of the actual product with the possibility to include variants.
For synthetic bushing materials this means:
— grade: one chemical composition, with our without reinforcements
— variants: various dimensions
Synthetic bushing materials using different chemical compositions, resins, fibres, filler material etc. are
considered to be different grades.
The Society's type approval for a synthetic bushing material is divided into four different main levels based
on the bushing material’s capability to withstand surface pressure in operational condition:
2
= type testing according to Sec.2 Table 1 and Sec.2 Table 2.
2
= type testing according to the general scheme: Sec.2 Table 1, plus testing of swell (dry/
wet/dry/wet cycles) and wear testing at increased pressure: Sec.2 Table 3.
5.5 N/mm
7.5 N/mm
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= type testing according to the general scheme: Sec.2 Table 1, plus testing of swell (dry/
wet dry/wet cycles) and wear testing at increased pressure: Sec.2 Table 3. Additionally,
satisfactory service experience from rudder bearing application in minimum 2.5 years (at
2
minimum 5.5 N/mm ) in at least two different vessels classed with the Society shall be
documented.
2
Type approvals issued for surface pressures above 5.5 N/mm will be issued with a statement that area of
2
application will be evaluated during approval of certified products if the surface pressure exceeds 5.5 N/mm .
2
Further, a maximum surface pressure of 10 N/mm will be subject to evaluation w.r.t. service experience etc.
in connection with renewal of a certificate.
The type approval will normally only cover water and/or oil lubrication, however, for self-lubricating materials
that have documented good performance in lubricated systems for several years it will be possible to apply
for an approval covering also non-lubrication (see Sec.2 [5]).
The Society's type approval for a synthetic propeller shaft bearing material is given for pressure up to 0.6
MPa (6 bar).
The type approval certificate is normally limited to one manufacturer at one production site, however, other
arrangements may be agreed upon with the Society.
Type tests as specified in Sec.2 [3], shall be carried out and verified in one of the following ways:
— at a DNV GL laboratory
— at an accredited and recognized testing laboratory or a laboratory accepted by the Society
— at the manufacturer’s premises in the presence of a surveyor.
The type test results shall be submitted to the Society in form of a test report according to ISO 17025 and
the additional requirements of the relevant test standard for evaluation.
1.3 Application
DNV GL rules for classification - ships, RU SHIP Pt.3 Ch.14 and RU SHIP Pt.4 Ch.4 require that synthetic
bushing materials for rudder bearings and propeller shafts are type approved in accordance with this CP for
equipment to be installed on vessels classed with the Society.
A TA certificate in accordance with this CP will confirm compliance with the requirements given in the rules as
specified in [1.1]. The TA certificate will not confirm compliance with requirements given in other parts of the
rules. In case additional requirements given in other parts of the rules shall be covered by the TA certificate,
this shall be specified in the application for TA and will be stated in the TA certificate.
1.4 Application for renewal after five (5) years
Application for renewal should be submitted to the Society not later than three (3) months before expiry date
of the type approval certificate.
The application shall include updated type approval documentation as specified in Sec.2.
Upon receipt of the application, the Society will perform a renewal assessment with main objective to verify
that the product properties, material composition and the product marking are not altered since issuance of
the type approval certificate.
Provided an approval of manufacturer certificate (see DNVGL CP 0421 Manufacturer of Fibre Reinforcements)
which is still valid for at least one year is available, an exemption from the obligation concerning retention
and renewal surveys listed in the class programme DNVGL CP 0338 Type Approval scheme will typically
apply.
If there, since last issuance of the type approval certificate, has been any change in the relevant standards or
in the Society’s rules, new assessment of product and type tests may be required.
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Section 1
2
10 N/mm
Standards referred to in this document:
—
—
—
—
—
—
ISO 9001:2008, Quality management systems - Requirements
ISO 604, Plastics - Determination of compressive properties.
ISO 175, Plastics - Methods of test for the determination of the effects of immersion in liquid chemicals.
ASTM D1141, Standard Practice for the Preparation of Substitute Ocean Water.
ISO 1817, Rubber, vulcanized - Determination of the effect of liquids.
ASTM D696, Standard Test Method for Coefficient of Linear Thermal Expansion of Plastics Between -30°C
and 30°C With a Vitreous Silica Dilatometer.
— ASTM G77-05(2010), Standard Test Method for Ranking Resistance of Materials to Sliding Wear Using
Block-on-Ring Wear Test.
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Section 1
2 References
For TA of synthetic bushing materials for rudder bearings and propeller shafts the following documentation
shall be submitted by the manufacturer at initial type approval and updated, at renewal. The documentation
shall, to the extent possible, be submitted as electronic files. The manufacturer shall keep one (1) copy of
type approval documentation in their own file. The documentation that forms the basis for the TA shall be
easily available for surveyors at the TA applicant’s premises. When documentation is submitted in paper
format, normally two copies of the documentation shall be submitted to the Society. No documentation will
be returned to the company applying for TA.
The documentation shall be in the English language, if not otherwise agreed. (Please number documentation
according to below list to facilitate review):
1)
2)
type designation, i.e. product name (grade) with list of variants to be included in and stated on the type
approval certificate
name and address of the manufacturer, to be listed on type approval certificate. The following shall be
specified:
—
—
—
—
—
—
details for all relevant production places
manufacturer’s name
mailing address
contact person
phone and fax number
e-mail and web address (if applicable)
3)
basis for approval. A reference of applicable rules and standards which the product shall comply with
(see [1.1])
4)
product description:
—
—
—
—
—
5)
resin or matrix material used
fibre reinforcement, if any
impregnation/lubrication, if self-lubricating
isotropic or anisotropic behaviour
elastomeric or non-elastomeric type
field of application and special limitations of the product, including e.g.:
— operation in cold climate, possible shrinkage
— arrangements for securing
— installation procedures
6)
product specification, technical data sheet, material safety data sheet, and engineering manual
including:
— properties as specified in tables in Sec.2 [3] nominal values and tolerances if requested
— maximum nominal surface pressure
— dimensions and relations that are produced and acceptable according to the manufacturer:
—
—
—
—
—
—
min. - max. diameter
min. - max. thickness
diameter/height (d/h) ratio
thickness/diameter (t/d) ratio
interference fitting tolerance data
other, if relevant
— acceptable mating material (shaft; type of material, roughness, hardness etc.)
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Section 1
3 Documentation
— type of lubrication(s) required, if any
— maximum service temperature and peak temperature if relevant
7)
description of production processes, including standard operating procedures (SOP)
8)
description of quality assurance system or copy of ISO 9001 certificate
9)
quality plan for synthetic bushings intended to be installed on board ships
1
1
10) test results (from tests already carried out) with references to standards, methods etc.
11) information regarding marking of the product or packaging
1
12) in-service experience, if available
13) witnessed type test results and initial assessment report by the Society’s local office shall be submitted
when completed
14) list of test and measuring equipment including calibration certificate.
1
To be verified by initial assessment prior to issuance of type approval certificate
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Section 1
— minimum and maximum installation clearance (take into account swell, edge and thermal effects). If
test results show less than 0.1% swell in total (non-swelling material), a minimum clearance below
1.5 mm (IACS requirement) can be discussed and agreed upon
Section 2
SECTION 2 GENERAL REQUIREMENTS
1 Design requirements
The synthetic bushing materials for rudder bearings and propeller shafts shall comply with the relevant
requirements given in the rules listed in Sec.1 [1.1].
2 Requirements for production and quality control arrangement
The manufacturer should have a quality system that meets ISO 9001 standards, or equivalent. If this quality
standard is not fulfilled, the extent of type testing and assessments will be specially considered.
The quality control arrangement in production will be checked with respect to:
— control of incoming materials
— scope of quality control, i.e. proof that test methods, test quantity and test equipment complies to the
applicable standard EN or ISO traceability and marking system
— production records
— storage condition and procedure.
3 Requirements for material
The extent of type testing is described in the following. It shall be noted that all tests shall be carried out
at temperature from 20°C and upwards. The manufacturer shall inform whether there will be any different
behavior of the material at lower temperatures as vessels will normally operate in temperatures down to and
below 0°C.
3.1 Extent of type tests, for all surface pressures
Table 1 General scheme for type testing, all surface pressures
Property
Unit
Test method
Definition
of
value
Level of
verification
Frequency
of
verification
Max. 4%
deformation
m+
2sdev
The Society
witness
2)
of test
Initial
renewal
Min.
100 N/
2
mm
m2sdev
The Society
witness
2)
of test
Initial
renewal
Number and
Acceptance
selection of specimen
criteria
1)
COMPRESSIVE PROPERTIES
Compressive deformation
Elastomeric:
max. allowable
deformation at
a compressive
stress equal
2
to 120 N/mm
%
Test method to
be specified by
manufacturer.(ISO
604, if relevant)
Isotropic: min. 5
Anisotropic: min. 10
Compressive strength
Nonelastomeric:
*
(flatwise )
N/
2
mm
ISO 604
Isotropic: min. 5
Anisotropic: min. 10
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Unit
Test method
1)
Definition
of
value
Level of
verification
Min.
85 N/
2
mm
m2sdev
The Society
witness
2)
of test
Min.
1000
2
N/mm
m2sdev
The Society
witness
2)
of test
Initial
renewal
The Society
witness of
start-up and
completion
2)
of test
Initial
Number and
Acceptance
selection of specimen
criteria
Nonelastomeric:
**
(edgewise )
Only required
for strips
and staves
Frequency
of
verification
Compressive modulus
Nonelastomeric:
*
(flatwise )
N/
2
mm
ISO 604
Isotropic: min. 5
Anisotropic: min. 10
EFFECT OF WATER
3)
Water Swelling
20°C
and
%
80°C
ISO 175 4 weeks
in substitute ocean
water (ASTM D1141)
at 20°C and 80°C.
Min. 3 specimen at
each temperature.
Samples, tube
segment or flat piece Volumetric
with dimension;
NonAll
50x50xt mm, t is
swelling:
results
min. 4 mm or the
-if <
below
min. thickness of the
0.1%.
bushing produced
require(will be stated on the Swelling:
ment
-if 0.1 to
certificate).Testing
max. 3%
immediately
after extraction
(wet condition)
Water resistance
Elastomeric
Nonelastomeric
%
Max. allowable
deformation at
a compressive
stress equal to 120
2
N/mm , after 4
weeks in substitute
ocean water (ASTM
D1141) at 20°C
%
ISO 604
Compression test
after 4 weeks in
substitute ocean
water (ASTM
D1141) at 20°C
Isotropic: min. 5
Anisotropic: min. 10
Max. 4%
deformation
m+
2sdev
The Society
witness of
compression
2)
test
Initial
Isotropic: min. 5
Anisotropic: min. 10
Min. 80%
retention
of
specified
strength
and
modulus
m2sdev
The Society
witness of
compression
2)
test
Initial
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Section 2
Property
Unit
Test method
Number and
Acceptance
selection of specimen
criteria
1)
EFFECT OF OIL
Oil swelling
20°C
%
ISO 175
4 weeks in oil no.3
(ISO 1817) at 20°C
Definition
of
value
Level of
verification
Frequency
of
verification
The Society
witness of
start-up and
completion
2)
of test
Initial
3)
min. 3specimen
with dimension;
Volumetric
50x50xt mm, t is
Nonmin. 4 mm or the
All
swelling:
min. thickness of the
results
if < 0.1% below
bushing produced
(will be stated on the
Swelling requirecertificate).Testing
ment
if 0.1 to
immediately
max. 3%
after extraction
(wet condition)
EFFECT OF TEMPERATURE
Temperature resistance
Elastomeric
Nonelastomeric
%
Max. allowable
deformation at a
compressive stress
2
equal to 120 N/mm ,
after heating the
test sample up to a
temperature of 50°C
%
ISO 604
Compression test
after heating the
test sample up to a
temperature of 50°C
Isotropic: min. 5
Anisotropic: min. 10
Isotropic:
min. 5
Anisotropic:
min. 10
Max. 4%
deformation
m+
2sdev
The Society
witness of
compression
2)
test
Initial
Min. 80%
retention
of
specified
strength
and
modulus
m2sdev
The Society
witness of
compression
2)
test
Initial
msv
-
-
Initial
Thermal expansion
*
(flatwise ) and
**
(edgewise )
mm/
mm°C
ASTM D696
-
See end of Table 3 for notes and legends
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Section 2
Property
2
Table 2 Surface pressure up to 5.5 N/mm
Property
Unit
Test method
1)
Number and
selection of
specimen
Acceptance
criteria
Definition
of value
Level of
verification
Frequency of
verification
-
The Society
witness of
start-up and
completion
of test
Initial
WEAR
Wear
See the
Society’s
wear
test
below
See the Society’s
wear test. Other
test methods can
be agreed upon
prior to testing.
See the
Society’s wear
test below
Wear rate
test shall
demonstrate
that a service
of min. 10
years in rudder
application can
be expected.
FRICTION
Dynamic
(only one
cycle is
sufficient)
Static
-
Recorded by a
simple, recognised
method at both
20°C and 80°C
preferably as
a function of
pressure or
minimum at
two different
Min. 3 specimen
at each
temperature
Max. 0.25
and surface
pressure.
All results
below
requirement
The Society
witness of
test setup and
Initial
recording of
test results
surface pressures
(max. and twice
the max.).
See end of Table 3 for notes and legends
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Section 2
3.2 Extent of type tests, for surface pressures up to 5.5 Mpa
2
Table 3 Increased surface pressure above 5.5 N/mm and up to max. 10 N/mm
Property
Unit
Test method
1)
Number and
selection of
specimen
Acceptance
criteria
EFFECT OF WATER/DRYING
ISO 175 wet/
dry/wet/.
cycle; 3 days wet
+ 3 days dry for
Water
swelling
%
4 weeks in
substitute ocean
water (ASTM D1141)
at 20°C. Shall
initiate and end with
3 days wet.
Min. 3 specimen,
tube segment or
flat piece with
dimension; 50×50×t
mm, t is min. 4
mm or the min.
thickness of the
bushing produced
(will be stated on
the certificate).
Testing immediately
after immersion
(wet condition)
Definition
of value
2
Level of
verification
Frequency
of
verification
3)
Volumetric
non-swelling:
-if < 0.1%
Swelling:
-if 0.1 to
max. 3%
The
Society
witness
All results
of startbelow
up and
requirement
completion
2)
of test
Initial
-
The
Society
witness
of startup and
completion
of test
Initial
All results
below
requirement
The
Society's
witness of
test setup and
recording
of test
results.
Initial
WEAR
Wear
See the
Society’s
See the Society’s
wear
wear test procedure.
test
procedure
See the Society’s
wear test procedure
Wear rate
test shall
demonstrate
that a service
of min.
10 years
in rudder
application
can be
expected.
FRICTION
Dynamic
Static
-
-
Coefficient of friction
to be recorded by a
recognised method:
20°C: During/in
connection with the
Society’s wear test.
I.e. two different
surface pressures
(max. and twice
the max.) and
both dry and wet
condition. 80°C: By
a simple, recognised
method at two
different surface
pressures (max. and
twice the max.).
20°C:
as per the
Society‘s wear test
procedure
Max. 0.25
80°C:
min. 3
specimen at
each pressure.
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Section 2
3.3 Extent of type tests, for surface pressures from 5.5 up to 10 Mpa
Unit
Test method
1)
Number and
selection of
specimen
Acceptance
criteria
Definition
of value
Level of
verification
Frequency
of
verification
The following notes and legends applies to Table 1, Table 2 and Table 3:
1)
other standards may be accepted by the Society prior to testing
2)
report from independent laboratory may be acceptable
3)
swelling of 3% and more will in general not be accepted
* flatwise - perpendicular to sheet plane
** edgewise - parallel to sheet plane.
Legend:
msv: manufacturer’s specified value.
m-2sdev: mean - 2 standard deviation of Type Test results.
m+2sdev: mean + 2 standard deviation of Type Test results.
Initial: Initial Assessment
Retention: Periodical Assessment, carried out after two (2) years
Renewal: Periodical Assessment, carried out after five (5) years
4 Wear testing procedure for synthetic rudder bearing bushing
materials
Other dimensions, parameters than listed below may be accepted by the Society after agreement, prior to
testing.
Test set-up consisting of a:
— oscillating shaft = diameter (dsh) = 100 mm
— sample shall be a fixed bearing segment = shall cover minimum 50° of the shafts circumference (width)
with a length of the bearing; hb = 1.2 dsh (length max. 120 mm for a 100 mm shaft and min. 80 mm) (if
larger samples shall be used, keep the same relation). The bearing diameter shall be db = dsh + 1 mm or
according to manufacturer's recommendations
— Seawater lubrication facility.
Test parameters:
— oscillating shaft = ± 15°
2
— surface pressure = Testing shall be carried out at the requested surface pressure (max. 10 N/mm ).
Additionally, testing shall be carried out at a surface pressure two times the requested pressure (i.e. max.
2
20 N/mm )
— lubrication = both dry and artificial seawater.
— air temperature = 20°C
— velocity = velocity of 3.5 mm/s
— movement = the shaft movement shall go on continuously at the requested surface pressure. At surface
pressures above the requested level, a pause/break may be allowed in periods up to 10 s at each pass of
centreline, upon agreement with the Society prior to starting the testing and will be stated as a limitation
to applicable PV (Pressure and Velocity - heat generation)
— actual running time/duration = until stable wear rate has been established (minimum 192 hours at 3.5
mm/s) or maximum 850 hours (excluding disassembling and pauses/breaks). For lower velocities and/or
longer pauses/breaks, the duration shall be increased accordingly.
Mating material:
— type = stainless steel
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Section 2
Property
Parameters to be recorded:
— wear shall be measured on bushing as well as on the liner/shaft, continuously or regularly. If regularly,
wear to be measured by disassembling every 48 hours until demonstrated by minimum four points of
measurements that a stable wear rate is achieved. The following shall be presented both tabulated and
graphically:
— wear vs. time (mm/h) and pressure
— wear vs. test cycle
— wear vs. kilometres of travel
— coefficient of friction shall be measured (continuously/regularly) until the wear rate has stabilised at 20°C.
Coefficient of friction vs time and pressure to be presented both tabulated and graphically
— all quantified parameters to be measured
— thermocouple, if relevant (shall coordinate thermic expansion and measured wear, in order to distinguish
these two parameters.
Swell due to thermal expansion and/or water swell shall be taken into account when specifying wear.
5 Approval for use in non-lubrication (dry-running) applications
This section applies only to synthetic rudder bearing bushing materials manufactured as self-lubrication
types, i.e. they include fillers or similar that promotes self-lubrication. The manufacturer's technical data
sheet or product description shall clearly state that the material is manufactured as, and suitable for, selflubrication.
2
Initially, the manufacturer may apply for dry-running up to a surface pressure of 5.5 N/mm . When
2
satisfactory performance at 5.5 N/mm has been documented for the bushing material in service for a
minimum 2.5 years, plus testing according to Table 2, a surface pressure of 7.5 MPa may be applied for, etc.
In order to include applications without water and/or oil lubrication, i.e. dry-running, the following additions
shall be made to the Society's wear testing procedure given in [4]:
— in dry condition only; continuously or regularly monitoring of temperature in the bushing material close to
the contact surface
— the running time/duration of the wear test shall be as stated in [4], however, also a stable temperature
shall be established before test is ended
— the bushing temperature shall not exceed the maximum service temperature set by the manufacturer, and
in any case it shall not exceed:
— for non-elastomeric materials; heat distortion temperature (HDT) –20°C
— for elastomeric materials; 50°C, or subject to evaluation for each case.
As an example, the following may be stated on the front page of the type approval certificate, when dryrunning is included:
“Maximum surface pressure 5.5 MPa for the synthetic bearing against steel, non-lubricated, and maximum
10 MPa water or oil lubricated. The type approval is valid only when the installation/application of the product
is according to the DNV GL rules and the manufacturer's specification.”
6 Approval of synthetic propeller shaft bearing materials
There are in principle three alternative ways of obtaining a type approval for propeller shaft bearing
materials:
— compliance with this class programme
— good and well documented service experience in conventional vessels for minimum 2 years, or
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Section 2
— hardness = max. 220 HV5
— mating materials surface roughness = fine turned to Ra = 0.8 µm
— clearances = db = dsh + 1 mm, hence max. 1 mm on diameter or according to manufacturer's
recommendations.
7 Wear testing procedure for synthetic propeller shaft bearing
materials
Wear test for synthetic propeller shaft bearing materials with continuous motion (on the basis of ASTM G77):
—
—
—
—
—
—
—
—
—
—
mating material: shaft made of stainless steel (about HRC 50)
diameter of shaft: the shaft diameter is depending on the bearing size but it shall be ≥ 35 mm
motion of shaft: continuous gliding
circumferential velocity: 6 m/s for oil or water lubrication, and 3 m/s for grease lubrication
lubrication: sea water (room temperature) and mineral oil (80°C), grease (80°C) if applicable
surface roughness: Ra = 0.5 mm
interface pressure: min. 0.6 MPa but in case of higher surface pressure it will be stated on the certificate
duration of test: until coefficient of wear remains constant (at least 192 h, not exceeding 840 h)
in order to obtain mixed lubrication, the test shall be interrupted every 8 hours.
dimensions of test sample.
Figure 1 Test sample dimensions
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Section 2
— based on a test programme developed by the manufacturer, evaluated and approved by the Society. The
test programme shall address low, medium and high speed running, potential high surface load peaks in
slow running mode etc.
— wear shall be measured on bushings as well on the shaft, continuously or regularly. If regularly, wear to
be measured by disassembling every 48 hours until a constant wear rate has been achieved (minimum of
four points of measurements). The measurements shall be presented both tabulated and graphically.
— wear vs. time (mm/h) and pressure
— coefficient of friction
— test distance [h]
— temperature of test sample during test cycle.
8 Requirements for marking of product
The product or package shall be marked. The marking shall at least include the following information:
—
—
—
—
—
product name
manufacturer’s name and address or trade mark
storage instruction
production date/batch number
quality guarantee period, if any.
The marking shall be carried out in such a way that it is visible, legible and indelible. The marking of product
shall enable traceability to the Society's type approval certificate.
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Section 2
Parameters to be recorded:
1 All surface pressures – entry of type test results
Table 1 General scheme for type testing, all surface pressures – type test results
Property
Test method
Definition
of value
Acceptance criteria
Manufacturer’s
Specification
Type Test
results
COMPRESSIVE PROPERTIES
Compressive deformation
Elastomeric:
Max. allowable
deformation at a
compressive stress
Max. 4%
deformation
Test method to
be specified.
m + 2sdev
2
equal to 120 N/mm
Compressive strength
Non Elastomeric:
(flatwise*)
Non Elastomeric:
(edgewise**)
Min. 120 N/mm
2
m - 2sdev
ISO 604
Min. 85 N/mm
Only required for
strips and staves
2
m - 2sdev
Compressive Modulus
Non Elastomeric:
(flatwise*)
ISO 604
Min. 1500 N/mm
2
m - 2sdev
EFFECT OF WATER
Water Swelling
20°C
80°C.
ISO 175
4 weeks in
substitute
ocean water
(ASTM D1141)
Volumetric
Non swelling:
-if < 0.1%
Swelling:
All results
below
requirement
-if 0.1 to max. 3%
Water resistance
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Appendix A
APPENDIX A GENERAL SCHEME FOR TYPE TESTING
Test method
Acceptance criteria
Definition
of value
Max. 4%
deformation
m + 2sdev
Min. 80% retention
of specified
strength and
modulus
m - 2sdev
Manufacturer’s
Specification
Type Test
results
Max. allowable
deformation at a
Elastomeric
compressive
stress equal to
2
120 N/mm ,
after 4 weeks in
substitute ocean
water (ASTM
D1141)
at 20°C
ISO 604
Compression test
Non elastomeric
after 4 weeks in
substitute ocean
water (ASTM
D1141) at 20°C
EFFECT OF OIL
Oil swelling
Volumetric
Non swelling if
ISO 175
4 weeks in oil
no.3 (ISO 1817)
< 0.1%
Swelling if
at 20°C
All results
below
requirement
0.1 to max. 3%
EFFECT OF TEMPERATURE
Temperature resistance
Elastomeric
Max. allowable
deformation at
a compressive
stress equal to
2
120 N/mm , after
heating the test
sample up to a
Max. 4%
deformation
m + 2sdev
Min. 80% retention
of specified
strength and
modulus
m - 2sdev
temperature of 50°C
ISO 604
Compression test
Non elastomeric
after heating the
test sample up to a
temperature of 50°C
Thermal expansion
(flatwise*)
(edgewise**)
ASTM D696
msv
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Appendix A
Property
2
Table 2 Surface pressure up to 5.5 N/mm - type test results
Property
Test method
Acceptance criteria
Definition
of value
Manufacturer’s
Specification
Type Test
results
WEAR
See the Society’s
wear test procedure.
Other test methods
can be agreed upon
prior to testing
Wear
Wear rate test
shall demonstrate
that a service of
min. 10 years in
rudder application
can be expected.
-
FRICTION, DRY
Dynamic
20°C
Surface
Pressure
Pmax.
2 x Pmax
Pmax
80°C.
Static
20°C
Max. 0.25
All results
below
requirement
Max. 0.25
All results
below
requirement
different surface
2 x Pmax
pressures (Pmax and
twice the Pmax),
dry conditions.
Surface
Pressure
Pmax.
2 x Pmax
Pmax
80°C.
Recorded by a simple,
recognised method,
preferably as a
function of pressure or
minimum at two
Recorded by a simple,
recognised method,
preferably as a
function of pressure or
minimum at two
different surface
2 x Pmax
pressures (Pmax and
twice the Pmax),
dry conditions.
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Appendix A
2
2 All surface pressures – up to 5.5 N/mm - entry of type test
results
2
2
Table 3 Increased surface pressure above 5.5 N/mm and up to max. 15 N/mm - type test
results
Property
Acceptance
criteria
Test method
Definition
of value
Manufacturer’s
Specification
Type Test
results
EFFECT OF WATER/DRYING
ISO 175
wet/dry/wet/.
cycle; 3 days wet
+ 3 days dry for 4
weeks in substitute
ocean water
(ASTM D1141)
at 20°C. Shall
initiate and end
with 3 days wet.
Water swelling
Volumetric
Non-swelling:
-if < 0.1%
Swelling:
-if 0.1 to
max. 3%.
All results
below
requirement
Sample
dimension to
be reported.
WEAR
Wear rate test
shall demonstrate
that a service
of min. 10
years in rudder
application can
be expected.
See the Society’s
wear test.
Wear
-
FRICTION
Dynamic
Surface
Pressure
Pmax.
20°C
2 x Pmax
Pmax
Dry
Wet
Dry
Wet
Dry
Wet
Dry
80°C.
2 x Pmax
Static
Dry/ Wet
condition
Surface
Pressure
Wet
Coefficient of
friction to be
recorded by a
recognised method:
20°C:
as per the Society‘s
test method
80°C:
Max. 0.25
By a simple,
recognised method
at two different
surface pressures
(max. and twice
the max.).
All results
below
requirement
Dry/ Wet
condition
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Appendix A
2
3 All surface pressures – above 5.5 N/mm and up to max. 10 N/
2
mm - entry of type test results
Pmax.
20°C
2 x Pmax
Pmax
Test method
Dry
Wet
Dry
Wet
Dry
Wet
Dry
80°C.
2 x Pmax
Wet
Acceptance
criteria
Definition
of value
Max. 0.25
All results
below
requirement
Manufacturer’s
Specification
Type Test
results
Coefficient of
friction to be
recorded by a
recognised method:
20°C:
as per the Society‘s
wear test procedure
80°C:
By a simple,
recognised method
at two different
surface pressures
(max. and twice
the max.).
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Appendix A
Property
Changes – historic
CHANGES – HISTORIC
There are currently no historical changes for this document.
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