Your email address will not be published. Enter your email address to stay informed on our company activities, useful industry news, updates to the Technical Library, new spreadsheets, and more The Abbott Aerospace Technical Library is made possible by generous donations from our users. Please help us to maintain, improve and expand the library by making a contribution, giving us the means to expand our free technical library to include even more useful tools and references. Why do You do this for free? A lot of the library material does not originate with us so, with good conscience, we cannot charge for that part of the library.
|Genre:||Health and Food|
|Published (Last):||24 June 2013|
|PDF File Size:||4.22 Mb|
|ePub File Size:||10.71 Mb|
|Price:||Free* [*Free Regsitration Required]|
ECSS is a cooperative effort of the European Space Agency, national space agencies and European industry associations for the purpose of developing and maintaining common standards. Disclaimer ECSS does not provide any warranty whatsoever, whether expressed, implied, or statutory, including, but not limited to, any warranty of merchantability or fitness for a particular purpose or any warranty that the contents of the item are error-free. In no respect shall ECSS incur any liability for any damages, including, but not limited to, direct, indirect, special, or consequential damages arising out of, resulting from, or in any way connected to the use of this document, whether or not based upon warranty, business agreement, tort, or otherwise; whether or not injury was sustained by persons or property or otherwise; and whether or not loss was sustained from, or arose out of, the results of, the item, or any services that may be provided by ECSS.
Table of contents. Threaded fasteners handbook Figure - Joint Categories 1 to Figure - Joint Categories 7 to Figure - Joint Categories 13 to Figure — Fastener Dimensions Figure — Definition of the under-head bearing angle Figure — Thread Geometry Figure - Typical Preload vs. Applied Torque Graph Figure - Fastener Faying Surfaces Figure - Embedding Preload Decay Figure - Joint with Conical Mating Surfaces Figure - Self Tightening by Torsional Relaxation Figure - Typical Joint Components Figure — Fastener Stiffness Figure — Clamped Parts Stiffness Figure — Application of external axial load Figure — External Load Causing Gapping Figure — Joint Diagram for Compressive Loading Figure - The compression zone when multiple edge distances are present Figure - Typical Gasket Deflection Figure — Gasket Showing Hysteresis Figure — Extraction of the Joint from its Environment Figure - The Basic and Connector Bodies Figure — Basic and Connector Bodies of a Flange Figure - A Typical Eccentric Joint Figure - Interface Pressure Distribution after Preloading Figure - Typical Joint Eccentrically Loaded Figure - Redistribution of interface pressure with force FA1 not sufficient to cause gapping Figure - Joint Diagram with a Higher Preload Figure - A Symmetrical Shear Joint Figure - Shear Joint in Bearing Figure - Fastener Group with hole clearance Figure - Idealised Bearing Stresses Figure - Shear-Out Failure Figure - Shear loaded joint example Figure - Offset Loads on Fastener Groups Figure - Vector addition of the fastener loads Figure - Typical Earthing Arrangements Figure - Equipment Mounting Box Geometry Figure - Typical Constant Amplitude Loading Figure - Typical Fatigue Comparison Figure - Yield Load Controlled Tightening Figure - Forms of Corrosion Table Physical Dimensions of Fasteners Table - Derived Dimensions for Metric Fasteners Table - Approximate values for plastic deformation caused by embedding Table — Criteria for Axial Load Analysis Table - Thermal Conductivity of Materials Table - Analysis of cycles to failure Table 1.
This document addresses these aims with particular reference to Space Structures and related hardware. This constraint is reflected in the range of joint geometries covered and structural applications, and also the range of fastener types and materials for which data is presented.
This document is an update of the PSS taking into account more recent developments in the field. It is intended to standardise the analysis approach and corresponding documentation for threaded fastener joints developed in ECSS projects. All relevant margins of safety should be shown in verification documentation. For the purposes of making a clear and coherent handbook it was necessary to adopt a single consistent set of terminology.
The terminology that was chosen is presented in 3. To avoid confusion, it is recommended to refer to this section frequently when reading the document. The users of this document are engineers involved in design, analysis or verification of joints on structures used for space missions. It is a guidelines document; therefore it includes advisory information rather than requirements. This document is intended to be applicable to any type of joint that is mechanically connected by threaded fasteners e.
It is written for joints made from metallic materials. However, subject to the engineering judgement of the user, many of the procedures presented herein may be applicable to joints made from composite materials. Other clamped parts that have specialised functions include: washers, spacers, gaskets, etc. NOTE When added to the prevailing torque the resulting torque is called the installation torque.
Variable Meaning A Cross-section area of a joint part in the plane perpendicular to the fastener axis AS Effective cross-sectional area of a fastener for stress analysis Asm Effective cross-sectional area of a fastener for stiffness calculations Ath Area of the cylindrical surface assumed to fail during thread pull-out A0 Minimum cross-sectional area of a fastener shank A3 Cross-sectional area of a fastener based on the thread root diameter, d3 C Transverse width of an eccentric joint see Figure 7.
The combined thickness of all clamped parts measured without any externally preload or applied load. Variable Meaning a Load eccentricity distance from joint axis to axis of applied load ak Distance between the edge of the under-head bearing surface and the point of load introduction used for eccentric joints, see Section 6.
Additionally, it contains a number of sections on ancillary subjects related to joint design. In general, the user of this document will be experienced in structural design and will make use of the various sections as needed.
However, to assist the first time user and to provide a 'check list' of essential features to be considered when designing joints, this section includes a procedure guiding the user to the relevant sections of this document.
The various steps are discussed below and then summarised in a flow chart. The joint can then be represented by one of five main joint categories, which depend on its configuration and applied forces. Therefore, the first task is to define the physical extent of the joint within the structure, and identify its category see Section 5.
It is assumed that an analysis of the structural system in which joint exists has been carried out in sufficient detail to specify the loads transmitted via the joint.
A method is given in Clause 9 to deal with combined axial and shear loading which is assumed to be the most frequently encountered. This is dealt with in more detail in each section, as appropriate. However, it is recommended that the engineer, at an early stage in the design process, is aware of the influence of varying external joint loads on the loads transmitted by the fastener and at the clamped interface.
Reference is therefore made to Section 7. Section 6. Furthermore, certain joints have requirements for thermal conductivity to be either above or below certain limits. Section 10 covers the analysis of thermal conductivity. Worked examples are provided to illustrate the application of the proposed design procedures.
These effects are covered in Section 6. If, within the general design constraints, the joint meets neither the basic nor the detailed fatigue criteria, it may be necessary to reconsider the initial joint design concept. Section 13 discusses a number of corrosion mechanisms relevant to joint components and provides a checklist against which the proposed design can be assessed and possible problem areas identified. The method of preloading can be critical as this determines the accuracy with which the fastener preload can be achieved.
Section 12 covers a number of different methods of installing preloaded fasteners. Design data and estimates of achievable accuracy for the preload are given where appropriate. Section 14 contains advice on lubrication aspects and contains details of the characteristics of a selected range of fastener lubricants.
It is necessary to check later that the specified preloading method is capable of ensuring the preload accuracy to be achieved, and also that it is compatible with joint location and access constraints. This may be achieved either by testing the complete structure or by isolating and testing individual joints. These aspects are covered in Section Concentric Axially Loaded Joints, b.
ECSS-E-HB-32-23A: Threaded fasteners handbook (16 April 2010)
Threaded fasteners handbook. Your email address will not be published. Enter your email address to stay informed on our company activities, useful industry news, updates to the Technical Library, new spreadsheets, and more The Abbott Aerospace Technical Library is made possible by generous donations from our users. Please help us to maintain, improve and expand the library by making a contribution, giving us the means to expand our free technical library to include even more useful tools and references. Why do You do this for free? A lot of the library material does not originate with us so, with good conscience, we cannot charge for that part of the library.
ECSS E HB 32 23A Threaded Fasteners Handbook 4-16-10
Log In. Thank you for helping keep Eng-Tips Forums free from inappropriate posts. The Eng-Tips staff will check this out and take appropriate action. Click Here to join Eng-Tips and talk with other members!