Petroleum, petrochemical and natural gas industries - Flexible couplings for mechanical power transmission - General-purpose applications (ISO 14691:2008)

This International Standard specifies the requirements  for couplings for the transmission of power between  the rotating shafts of two machines for general  purpose applications in the petroleum, petrochemical  and natural gas industries. Such applications typically  require couplings to transmit power at speeds not  exceeding 4 000 r/min, between machines in which  the first lateral critical speed is above the running  speed range (stiff-shaft machines). It may, by  agreement, be used for applications outside these  limits. This International Standard is applicable to  couplings designed to accommodate parallel (or  lateral) offset, angular misalignment and axial  displacement of the shafts without imposing excessive  mechanical loading on the coupled machines.  Couplings covered by this International Standard  include gear (and other mechanical contact types),  metallic flexible-element and various elastomeric  types. Such couplings may be of all metal  construction or may include components of non- metallic materials such as composites. Special types  such as clutch, hydraulic, eddy-current, rigid and  radial-spline types, are not covered. This International  Standard covers design, materials of construction,  inspection and testing of couplings and methods of  attachment of the coupling to the shafts (including  tapered sleeve and other proprietary devices). This  International Standard does not define criteria for the  selection of coupling types for specific applications.

Erdöl-, petrochemische und Erdgasindustrie - Flexible Kupplungen für mechanische Kraftübertragung - Allgemeine Anwendungsfälle (ISO 14691:2008)

Industries du pétrole, de la pétrochimie et du gaz naturel - Accouplements flexibles pour transmission de puissance mécanique - Applications d'usage général (ISO 14691:2008)

L'ISO 14691:2008 spécifie les exigences applicables aux accouplements permettant la transmission de puissance entre les arbres rotatifs de deux machines pour des applications d'usage général dans les industries pétrolière, pétrochimique et du gaz naturel. Ces applications exigent généralement que les accouplements transmettent la puissance à des vitesses ne dépassant pas 4 000 r/min, entre des machines dans lesquelles la première vitesse latérale critique est supérieure à la plage de vitesses de marche (machines à arbre rigide). Ils peuvent, sous réserve d'un accord, être utilisés pour des applications en dehors de ces limites.
L'ISO 14691:2008 est applicable aux accouplements conçus pour compenser un déport parallèle (ou latéral), un désalignement angulaire et un déplacement axial des arbres sans imposer aux machines couplées une charge mécanique excessive. Les accouplements couverts par l'ISO 14691:2008 comprennent les accouplements à denture (et autres types de contact mécanique), les accouplements à éléments flexibles métalliques et divers accouplements en élastomère. Ces accouplements peuvent avoir une construction tout métal ou peuvent contenir des composants en matériaux non métalliques, tels que des composites.
L'ISO 14691:2008 couvre la conception, les matériaux de construction, le contrôle et les essais des accouplements ainsi que les méthodes de fixation de l'accouplement sur les arbres (y compris les dispositifs à douille conique et autres dispositifs spéciaux).
L'ISO 14691:2008 n'est pas applicable aux types spéciaux d'accouplements, tels que les accouplements à embrayage, hydrauliques, à courant de Foucault, rigides et à cannelures radiales.
L'ISO 14691:2008 ne définit pas de critères de sélection des types d'accouplements pour des applications spécifiques.

Petrokemična industrija ter industrija za predelavo nafte in zemeljskega plina - Prožne spojke za mehanski prenos energije - Uporaba za splošne namene (ISO 14691:2008)

General Information

Status
Published
Public Enquiry End Date
29-Feb-2008
Publication Date
18-Dec-2008
Technical Committee
Current Stage
6060 - National Implementation/Publication (Adopted Project)
Start Date
10-Dec-2008
Due Date
14-Feb-2009
Completion Date
19-Dec-2008

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SLOVENSKI STANDARD
SIST EN ISO 14691:2009
01-februar-2009
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SIST EN ISO 14691:2001
3HWURNHPLþQDLQGXVWULMDWHULQGXVWULMD]DSUHGHODYRQDIWHLQ]HPHOMVNHJDSOLQD
3URåQHVSRMNH]DPHKDQVNLSUHQRVHQHUJLMH8SRUDED]DVSORãQHQDPHQH ,62


Petroleum, petrochemical and natural gas industries - Flexible couplings for mechanical

power transmission - General-purpose applications (ISO 14691:2008)
Erdöl-, petrochemische und Erdgasindustrie - Flexible Kupplungen für mechanische
Kraftübertragung - Allgemeine Anwendungsfälle (ISO 14691:2008)

Industries du pétrole, de la pétrochimie et du gaz naturel - Accouplements flexibles pour

transmission de puissance mécanique - Applications d'usage général (ISO 14691:2008)

Ta slovenski standard je istoveten z: EN ISO 14691:2008
ICS:
21.120.20 Sklopke Couplings
75.180.20 Predelovalna oprema Processing equipment
SIST EN ISO 14691:2009 en

2003-01.Slovenski inštitut za standardizacijo. Razmnoževanje celote ali delov tega standarda ni dovoljeno.

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SIST EN ISO 14691:2009
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SIST EN ISO 14691:2009
EUROPEAN STANDARD
EN ISO 14691
NORME EUROPÉENNE
EUROPÄISCHE NORM
December 2008
ICS 75.180.20 Supersedes EN ISO 14691:2000
English Version
Petroleum, petrochemical and natural gas industries - Flexible
couplings for mechanical power transmission - General-purpose
applications (ISO 14691:2008)

Industries du pétrole, de la pétrochimie et du gaz naturel - Erdöl-, petrochemische und Erdgasindustrie - Flexible

Accouplements flexibles pour transmission de puissance Kupplungen für mechanische Kraftübertragung -

mécanique - Applications d'usage général (ISO Allgemeine Anwendungsfälle (ISO 14691:2008)

14691:2008)
This European Standard was approved by CEN on 28 November 2008.

CEN members are bound to comply with the CEN/CENELEC Internal Regulations which stipulate the conditions for giving this European

Standard the status of a national standard without any alteration. Up-to-date lists and bibliographical references concerning such national

standards may be obtained on application to the CEN Management Centre or to any CEN member.

This European Standard exists in three official versions (English, French, German). A version in any other language made by translation

under the responsibility of a CEN member into its own language and notified to the CEN Management Centre has the same status as the

official versions.

CEN members are the national standards bodies of Austria, Belgium, Bulgaria, Cyprus, Czech Republic, Denmark, Estonia, Finland,

France, Germany, Greece, Hungary, Iceland, Ireland, Italy, Latvia, Lithuania, Luxembourg, Malta, Netherlands, Norway, Poland, Portugal,

Romania, Slovakia, Slovenia, Spain, Sweden, Switzerland and United Kingdom.
EUROPEAN COMMITTEE FOR STANDARDIZATION
COMITÉ EUROPÉEN DE NORMALISATION
EUROPÄISCHES KOMITEE FÜR NORMUNG
Management Centre: rue de Stassart, 36 B-1050 Brussels

© 2008 CEN All rights of exploitation in any form and by any means reserved Ref. No. EN ISO 14691:2008: E

worldwide for CEN national Members.
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SIST EN ISO 14691:2009
EN ISO 14691:2008 (E)
Contents Page

Foreword ..............................................................................................................................................................3

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SIST EN ISO 14691:2009
EN ISO 14691:2008 (E)
Foreword

This document (EN ISO 14691:2008) has been prepared by Technical Committee ISO/TC 67 "Materials,

equipment and offshore structures for petroleum and natural gas industries" in collaboration with Technical

Committee CEN/TC 12 “Materials, equipment and offshore structures for petroleum, petrochemical and

natural gas industries”, the secretariat of which is held by AFNOR.

This European Standard shall be given the status of a national standard, either by publication of an identical

text or by endorsement, at the latest by June 2009, and conflicting national standards shall be withdrawn at

the latest by June 2009.

Attention is drawn to the possibility that some of the elements of this document may be the subject of patent

rights. CEN [and/or CENELEC] shall not be held responsible for identifying any or all such patent rights.

This document supersedes EN ISO 14691:2000.

According to the CEN/CENELEC Internal Regulations, the national standards organizations of the following

countries are bound to implement this European Standard: Austria, Belgium, Bulgaria, Cyprus, Czech

Republic, Denmark, Estonia, Finland, France, Germany, Greece, Hungary, Iceland, Ireland, Italy, Latvia,

Lithuania, Luxembourg, Malta, Netherlands, Norway, Poland, Portugal, Romania, Slovakia, Slovenia, Spain,

Sweden, Switzerland and the United Kingdom.
Endorsement notice

The text of ISO 14691:2008 has been approved by CEN as a EN ISO 14691:2008 without any modification.

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SIST EN ISO 14691:2009
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SIST EN ISO 14691:2009
INTERNATIONAL ISO
STANDARD 14691
Second edition
2008-12-01
Petroleum, petrochemical and natural gas
industries — Flexible couplings for
mechanical power transmission —
General-purpose applications
Industries du pétrole, de la pétrochimie et du gaz naturel —
Accouplements flexibles pour transmission de puissance mécanique —
Applications d'usage général
Reference number
ISO 14691:2008(E)
ISO 2008
---------------------- Page: 7 ----------------------
SIST EN ISO 14691:2009
ISO 14691:2008(E)
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COPYRIGHT PROTECTED DOCUMENT
© ISO 2008

All rights reserved. Unless otherwise specified, no part of this publication may be reproduced or utilized in any form or by any means,

electronic or mechanical, including photocopying and microfilm, without permission in writing from either ISO at the address below or

ISO's member body in the country of the requester.
ISO copyright office
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Tel. + 41 22 749 01 11
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Published in Switzerland
ii © ISO 2008 – All rights reserved
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SIST EN ISO 14691:2009
ISO 14691:2008(E)
Contents Page

Foreword............................................................................................................................................................ iv

Introduction ........................................................................................................................................................ v

1 Scope ..................................................................................................................................................... 1

2 Normative references ........................................................................................................................... 1

3 Terms and definitions........................................................................................................................... 2

4 Statutory requirements ........................................................................................................................ 5

5 Coupling selection................................................................................................................................ 5

5.1 General................................................................................................................................................... 5

5.2 Compliance............................................................................................................................................ 6

6 Purchaser's specification .................................................................................................................... 6

7 Coupling rating ..................................................................................................................................... 8

8 Construction requirements.................................................................................................................. 9

8.1 General................................................................................................................................................... 9

8.2 Materials of construction ................................................................................................................... 10

8.3 Coupling hubs..................................................................................................................................... 11

8.4 Bolting.................................................................................................................................................. 12

8.5 Electrical insulation............................................................................................................................ 12

8.6 Alignment provision ........................................................................................................................... 12

8.7 Rotor dynamic data ............................................................................................................................ 12

8.8 Non-horizontal applications .............................................................................................................. 13

8.9 Additional requirements for gear couplings.................................................................................... 13

8.10 Additional requirements for metallic flexible-element couplings.................................................. 13

8.11 Additional requirements for elastomeric couplings ....................................................................... 13

9 Balance ................................................................................................................................................ 14

9.1 Objectives............................................................................................................................................ 14

9.2 Balance quality.................................................................................................................................... 14

9.3 Additional balancing requirements................................................................................................... 15

9.4 Verification of coupling balance ....................................................................................................... 15

10 Accessories......................................................................................................................................... 15

11 Manufacturing quality, inspection, testing and preparation for shipment ................................... 15

11.1 Manufacturing quality......................................................................................................................... 15

11.2 Inspection and testing........................................................................................................................ 16

11.3 Preparation for shipment ................................................................................................................... 16

12 Vendor's data ...................................................................................................................................... 16

12.1 General................................................................................................................................................. 16

12.2 Proposals............................................................................................................................................. 16

12.3 Contract data....................................................................................................................................... 17

Annex A (informative) Examples of misalignment........................................................................................ 19

Annex B (informative) Example of the determination of potential unbalance ........................................... 21

Annex C (informative) Coupling tapers.......................................................................................................... 24

Annex D (normative) Coupling guards .......................................................................................................... 25

Annex E (informative) Coupling datasheets.................................................................................................. 27

Bibliography ..................................................................................................................................................... 32

© ISO 2008 – All rights reserved iii
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SIST EN ISO 14691:2009
ISO 14691:2008(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

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.

International Standards are drafted in accordance with the rules given in the ISO/IEC Directives, Part 2.

The main task of technical committees is to prepare International Standards. Draft International Standards

adopted by the technical committees are circulated to the member bodies for voting. Publication as an

International Standard requires approval by at least 75 % of the member bodies casting a vote.

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.

ISO 14691 was prepared by Technical Committee ISO/TC 67, Materials, equipment and offshore structures

for petroleum, petrochemical and natural gas industries, Subcommittee SC 6, Processing equipment and

systems.

This second edition cancels and replaces the first edition (ISO 14691:1999), which has been technically

revised.
iv © ISO 2008 – All rights reserved
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SIST EN ISO 14691:2009
ISO 14691:2008(E)
Introduction

Users of this International Standard should be aware that further or differing requirements may be needed for

individual applications. This International Standard is not intended to inhibit a vendor from offering, or the

purchaser from accepting, alternative equipment or engineering solutions for the individual application. This

may be particularly appropriate where there is innovative or developing technology. Where an alternative is

offered, the vendor should identify any variations from this International Standard and provide details.

For the following applications, the use of ISO 10441 is recommended:

⎯ large or high-speed machines that may be required to operate continuously for extended periods, are

often unspared and are critical to the continued operation of the installation (special-purpose

applications);

⎯ machines in which the first lateral critical speed is less than the maximum required operating speed

(flexible-shaft machines);

⎯ machines in which the rotor dynamics are particularly sensitive to coupling unbalance.

This International Standard requires the purchaser to specify certain details and features. A bullet (●) at the

beginning of a subclause or paragraph indicates that either a decision is required or that further information is

to be provided by the purchaser. This information should be indicated on the datasheet(s), typical examples of

which are included as Annex E, otherwise it should be stated in the quotation request or in the order.

The coupling vendor is not normally required to supply the coupling guard or guards. However, for

completeness and for the information of the user of this International Standard, Annex D, which provides

requirements for guards, has been added.
© ISO 2008 – All rights reserved v
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SIST EN ISO 14691:2009
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SIST EN ISO 14691:2009
INTERNATIONAL STANDARD ISO 14691:2008(E)
Petroleum, petrochemical and natural gas industries — Flexible
couplings for mechanical power transmission — General-
purpose applications
1 Scope

This International Standard specifies the requirements for couplings for the transmission of power between the

rotating shafts of two machines for general-purpose applications in the petroleum, petrochemical and natural

gas industries. Such applications typically require couplings to transmit power at speeds not exceeding

4 000 r/min, between machines in which the first lateral critical speed is above the running speed range (stiff-

shaft machines). It can, by agreement, be used for applications outside these limits.

NOTE 1 Recommendations are included in the Introduction as to when the use of ISO 10441 should be considered.

This International Standard is applicable to couplings designed to accommodate parallel (or lateral) offset,

angular misalignment and axial displacement of the shafts without imposing excessive mechanical loading on

the coupled machines. Couplings covered by this International Standard include gear (and other mechanical

contact types), metallic flexible-element and various elastomeric types. Such couplings can be of all metal

construction or can include components of non-metallic materials, such as composites.

This International Standard covers design, materials of construction, inspection and testing of couplings and

methods of attachment of the coupling to the shafts (including tapered sleeve and other proprietary devices).

This International Standard does not apply to special types of couplings, such as clutch, hydraulic, eddy-

current, rigid and radial-spline types.

This International Standard does not define criteria for the selection of coupling types for specific applications.

NOTE 2 In many cases, couplings covered by this International Standard are manufacturers' catalogue items.

2 Normative references

The following referenced documents are indispensable for the application 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 286-2:1988, ISO system of limits and fits — Part 2: Tables of standard tolerance grades and limit

deviations for holes and shafts

ISO 1940-1:2003, Mechanical vibration — Balance quality requirements for rotors in a constant (rigid) state —

Part 1: Specification and verification of balance tolerances
ISO 8821, Mechanical vibration — Balancing — Shaft and fitment key convention
ANSI/AGMA 9002, Bores and Keyways for Flexible Couplings (Inch Series)
ANSI/AGMA 9003, Flexible Couplings — Keyless Fits
ANSI/AGMA 9112, Bores and Keyways for Flexible Couplings (Metric Series)
© ISO 2008 – All rights reserved 1
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SIST EN ISO 14691:2009
ISO 14691:2008(E)
DIN 7190, Interference fits — Calculation and design rules
3 Terms and definitions
For the purposes of this document, the following terms and definitions apply.
3.1
angular misalignment

〈double-engagement couplings〉 two minor angles between the extension of each machine shaft centre-line

and the centre-line of the structure joining the two flexible elements
3.2
angular misalignment

〈single-engagement couplings〉 minor angle between the extensions of the shaft centre-lines of the two

coupled machines
3.3
axial displacement

change in the relative axial position of the adjacent shaft ends of two coupled machines, usually caused by

thermal expansion
3.4
continuous torque rating

coupling manufacturer's declared maximum torque that the coupling can transmit continuously for the

specified life
3.5
distance between shaft ends
DBSE

distance from the extreme end of one shaft (including any threaded end) to the extreme end of the next shaft

or, in the case of integral flanges, the distance from the mating faces
3.6
double-engagement coupling
coupling with two planes of flexure

NOTE This arrangement enables couplings of certain types, notably gear and metallic flexible-element types, that

cannot normally accommodate parallel (or lateral) offset, to do so.
3.7
gear coupling

coupling of the mechanical contact type that transmits torque and accommodates misalignment and axial

displacement by relative rocking and sliding motion between mating, profiled gear teeth

3.8
lateral offset

lateral distance between the centre-lines of two shafts that are not parallel, measured perpendicularly to the

centre-line and in the plane of the shaft end of the driving machine
See Annex A.
3.9
manufacturer
agency responsible for the design and fabrication of the coupling
NOTE The manufacturer is not necessarily the vendor.
1) Deutsches Institut für Normung, Burggrafenstraße 6, Berlin, Germany D-10787.
2 © ISO 2008 – All rights reserved
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SIST EN ISO 14691:2009
ISO 14691:2008(E)
3.10
maximum allowable speed
maximum speed for which the manufacturer has designed the coupling
3.11
maximum allowable temperature

maximum continuous temperature for which the manufacturer has designed the coupling

3.12
maximum continuous angular misalignment

maximum angular misalignment at each plane of flexure that the coupling is able to tolerate for the specified

life (5.1.3) when transmitting the coupling continuous torque rating at the coupling rated speed, and when

simultaneously subjected to the coupling maximum continuous axial displacement
3.13
maximum continuous axial displacement

maximum axial displacement the coupling is able to tolerate for the specified life (5.1.3) when transmitting the

coupling continuous torque rating at the coupling rated speed and when simultaneously subjected to the

coupling maximum continuous angular misalignment
3.14
maximum continuous speed

highest rotational speed at which the coupling, as made and tested, is capable of continuous operation

3.15
mechanical contact coupling

coupling designed to transmit torque by direct mechanical contact between mating parts and accommodate

misalignment and axial displacement by relative rocking and sliding motion between the parts in contact

NOTE 1 Examples of mechanical contact couplings are gear, grid, and pin-bushing couplings.

NOTE 2 The contacting parts can be metallic or can be made of self-lubricating non-metallic material.

NOTE 3 These couplings do not have a free-state position but resist change in the axial and angular direction, mainly

as a function of transmitted torque and the coefficient of friction between the contacting parts.

3.16
metallic flexible-element coupling

coupling that obtains its flexibility from the flexing of thin metallic discs, diaphragms or links

3.17
momentary torque limit

maximum instantaneous torque that the coupling can tolerate without suffering immediate failure

3.18
owner

final recipient of the equipment who may delegate another agent as the purchaser of the equipment

3.19
parallel offset

distance between the centre-lines of two coupled shafts that are parallel but not in the same straight line

See Annex A.
3.20
peak torque rating
maximum torque the coupling can tolerate for short periods
© ISO 2008 – All rights reserved 3
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SIST EN ISO 14691:2009
ISO 14691:2008(E)
3.21
pilot
rabbet
register
spigot

surface that positions a coupling component, sub-assembly, or assembly radially with respect to another

coupling component
3.22
potential unbalance
probable net unbalance of a complete coupling

NOTE 1 Potential unbalance results from a combination of the residual unbalance of individual components and

sub-assemblies and possible eccentricity of the components and sub-assemblies due to run-out and tolerances of the

various surfaces and registers. Since it can be assumed that the actual values of the various contributory unbalances are

random in both magnitude and direction, the numerical value of the potential unbalance is the square root of the sum of

the squares of all the contributory unbalances. Typical contributory unbalances are

a) the residual unbalance of each component or sub-assembly,

b) errors in the balance of each component or sub-assembly resulting from eccentricity in the fixture used to mount the

component or sub-assembly in the balance machine,

c) the unbalance of each component or sub-assembly due to eccentricity resulting from clearance or run-out of the

relevant registers or fits.

NOTE 2 The concept of potential unbalance is explained more fully, and a worked example is provided, in Annex B.

3.23
purchaser
agency that issues the order and the specification to the vendor

NOTE The purchaser can be the owner of the plant in which the equipment is being installed, the owner's appointed

agent or, frequently, the manufacturer of the driven machine.
3.24
rated speed

highest rotational speed at which the coupling is required to be capable of transmitting the continuous torque

rating while simultaneously subjected to the coupling rated axial displacement and the rated angular

misalignment (or the rated parallel or lateral offset in the case of a single-engagement coupling)

3.25
residual unbalance

level of unbalance remaining in a component or assembly after it has been balanced, either to the limit of the

capability of the balancing machine or in accordance with the relevant standard
3.26
service factor

factor applied to the steady-state torque in order to allow for off-design conditions, cyclic and other variations

as well as equipment variations resulting in a torque higher than that at the equipment normal operating point

3.27
single-engagement coupling
coupling with only one plane of flexure

NOTE This type of coupling can accommodate angular misalignment and axial displacement. Single-engagement

couplings of some types, notably gear and metallic flexible-element types, do not normally accommodate parallel (or

lateral) offset. Certain types of single-engagement couplings can accommodate offset misalignment to a limited extent.

3.28
spacer

part of a coupling that is removable to give access for maintenance and/or removal of the coupling hubs

NOTE The spacer can be a single component or an assembly.
4 © ISO 2008 – All rights reserved
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SIST EN ISO 14691:2009
ISO 14691:2008(E)
3.29
spacer gap length

distance between coupling hubs or sleeves in which the coupling spacer is installed

NOTE Spacer gap length is not necessarily equal to the distance between the shaft ends.

3.30
torsional stiffness

rate of change of the angular deflection with respect to the applied torque about the axis of rotation

NOTE With some types of couplings, the torsional stiffness is not constant but is a function of the magnitude of the

torque and, with oscillating torques, also the frequency.
3.31
trip speed

rotational speed at which the independent emergency overspeed device operates to shut down a variable-

speed prime mover or, for the purposes of this International Standard, in the case of alternating current

electric motors, the speed corresponding to the synchronous speed of the motor at line frequency or, in the

case of variable-frequency drives, at maximum supply frequency
3.32
unit responsibility

responsibility for co-ordinating the delivery and technical aspects of the equipment and all auxiliary systems

included in the scope of the order

NOTE The technical aspects for consideration include, but are not limited to, such factors as the power requirements,

speed, rotation, general arrangement, dynamics, noise, lubrication, sealing system, material test reports, instrumentation,

piping, conformance to specifications and testing of components.
3.33
vendor
supplier
agency that supplies the equipment

NOTE The vendor is the manufacturer of the equipment or the manufacturer's agent and normally is responsible for

service support.
4 Statutory requirements

The purchaser and the vendor shall mutually determine the measures taken to comply with any federal, state

or local codes, regulation
...

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