EN 74-2 specifies:
-   materials;
-   design requirements;
-   specified values for resistances and stiffnesses which a coupler has to achieve under test;
-   test procedures and assessment;
for the following special couplers:
-   screw or wedge half couplers, sleeve couplers with shear studs, right angle reduction couplers and swivel reduction couplers.
It gives recommendations for on going production control.
These couplers are for use principally in temporary works. Each coupler is able to be fixed to at least one side to one 48,3 mm diameter steel or aluminium tube. For the other side of reduction couplers, this standard specifies requirements for the diameter and wall thickness of tubes.
For testing, screw couplers are tightened with a torque of 50 Nm and wedge couplers are tightened with a 500 g hammer until the jarring blow.
Other special half couplers such as half couplers attached by riveting, used mainly for members of prefabricated scaffolds, are outside the scope of this document.
NOTE   Information on design using special couplers is given in Annex B.

  • Standard
    43 pages
    English language
    sale 10% off
    e-Library read for
    1 day
  • Draft
    41 pages
    English language
    sale 10% off
    e-Library read for
    1 day

This document specifies, for right angle couplers, swivel couplers, sleeve couplers and parallel couplers working by friction:
-   materials;
-   design requirements;
-   strength classes with different structural parameters including values for resistance and stiffness;
-   test procedures;
-   assessment;
and gives
-   recommendations for ongoing production control.
For testing, screw couplers are tightened to a torque of 50 Nm and wedge couplers are tightened with a 500 g hammer until the jarring blow.

  • Standard
    46 pages
    English language
    sale 10% off
    e-Library read for
    1 day
  • Draft
    46 pages
    English language
    sale 10% off
    e-Library read for
    1 day

IEC 60744:2018 provides requirements and recommendations for the design, construction and test of safety logic assemblies used in safety systems to perform category A safety functions (in accordance with IEC 61226). Safety logic assemblies include logic such as the hardwired logic assembly interfacing computer-based systems to switchgear, actuators or contactors to provide trip or engineered safety feature actuations. Safety logic assemblies are significant parts of a safety system and may include voting logic between redundant channels. This document provides a general description of safety logic assemblies for safety actuators control. The principles to meet dependability objectives are presented. The main features relating to the design requirements are described and explained.
This new edition includes the following significant technical changes with respect to the previous edition:
a) update of the references to standards published or revised since the issue of the first edition of the current standard, including IEC 61513 and IEC 61226;
b) additional requirements for operational and maintenance bypass use; requirements of voting logic; and others.

  • Standard
    70 pages
    English and French language
    sale 15% off

Includes principles of design, construction and testing of safety logic assemblies used in protection systems. Gives recommendations for the implementation of the general principles of nuclear reactor instrumentation in IEC 60231A. It includes provisions for acceptance and in-service testing reliability criteria and protection from external influences. Safety logic functions performed within the safety logic assemblies are not included. IEC 60744 is no longer up-to-date and will not be revised by IEC. The standard is maintained for the time being for bibliographical purposes and because it was used in the past for the design of nuclear power plants which are still in operation.

  • Standard
    16 pages
    English and French language
    sale 15% off

ISO 14691:2008 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). ISO 14691:2008 can, by agreement, be used for applications outside these limits.
ISO 14691:2008 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 ISO 14691:2008 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.
ISO 14691:2008 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).
ISO 14691:2008 does not apply to special types of couplings, such as clutch, hydraulic, eddy-current, rigid and radial-spline types.
ISO 14691:2008 does not define criteria for the selection of coupling types for specific applications.

  • Standard
    40 pages
    English language
    sale 10% off
    e-Library read for
    1 day

This International Standard specifies the requirements for couplings for the transmission of power between the rotating shafts of two machines in special-purpose applications in the petroleum, petrochemical and natural gas industries. Such applications are typically in large and/or high speed machines, in services that can be required to operate continuously for extended periods, are often unspared and are critical to the continued operation of the installation. By agreement, it can be used for other applications or services. Couplings covered by this International Standard are designed to accommodate parallel (or lateral) offset, angular misalignment and axial displacement of the shafts without imposing unacceptable mechanical loading on the coupled machines. It is applicable to gear, metallic flexible element, quill shaft and torsionally resilient type couplings. Torsional damping and resilient type couplings are detailed in Annex A; gear-type couplings are detailed in Annex B and quill shaft style couplings are detailed in Annex C. This International Standard covers the design, materials of construction, manufacturing quality, inspection and testing of special-purpose couplings.

  • Standard
    64 pages
    English language
    sale 10% off
    e-Library read for
    1 day

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.

  • Standard
    40 pages
    English language
    sale 10% off
    e-Library read for
    1 day

Gives specifications in order to facilitate communication and understanding. Does not apply to rigid flange or sleeve couplings; torsionally stiff couplings for alignment purposes, all types of slip couplings. Does not give dimensional requirements for either shafts or couplings.

  • Standard
    3 pages
    English language
    sale 15% off
  • Standard
    3 pages
    French language
    sale 15% off
  • Standard
    3 pages
    French language
    sale 15% off

Migrated from Progress Sheet (TC Comment) (2000-07-10): // ENQ. missed, UAP on ISO 14691 when published (JS/990414)

  • Standard
    28 pages
    English language
    sale 10% off
    e-Library read for
    1 day