1、August 2012 Translation by DIN-Sprachendienst.English price group 12No part of this translation may be reproduced without prior permission ofDIN Deutsches Institut fr Normung e. V., Berlin. Beuth Verlag GmbH, 10772 Berlin, Germany,has the exclusive right of sale for German Standards (DIN-Normen).ICS
2、 21.120.40!$k“1907204www.din.deDDIN ISO 21940-32Mechanical vibration Rotor balancing Part 32: Shaft and fitment key convention (ISO 21940-32:2012),English translation of DIN ISO 21940-32:2012-08Mechanische Schwingungen Auswuchten von Rotoren Teil 32: Behandlung von Passfederverbindungen (ISO 21940-3
3、2:2012),Englische bersetzung von DIN ISO 21940-32:2012-08Vibrations mcaniques quilibrage des rotors Partie 32: Convention relative aux clavettes darbres et aux lments rapports(ISO 21940-32:2012),Traduction anglaise de DIN ISO 21940-32:2012-08SupersedesDIN ISO 8821:1991-10www.beuth.deDocument compris
4、es pagesIn case of doubt, the German-language original shall be considered authoritative.2107.12 A comma is used as the decimal marker. Contents Page National foreword .3 National Annex NA (informative) Bibliography 4 Introduction .5 1 Scope 6 2 Normative references 6 3 Terms and definitions .6 4 Ha
5、lf-key convention .6 5 Marking .8 6 Implementation of the half-key convention 9 Annex A (normative) Specifications for the half-key convention . 10 Annex B (informative) Practical considerations for making half-keys and usage of keys . 12 Annex C (informative) Comparison between shaft and fitment ke
6、y conventions . 18 Bibliography . 21 2 DIN ISO 21940-32:2012-08 DIN ISO 21940-32:2012-08 3 National foreword This standard includes safety requirements. This standard has been prepared by Technical Committee ISO/TC 108 “Mechanical vibration, shock and condition monitoring”, Subcommittee SC 2 “Measur
7、ement and evaluation of mechanical vibration and shock as applied to machines, vehicles and structures” (Secretariat: DIN, Germany). The responsible German body involved in its preparation was the Normenausschuss Akustik, Lrmminderung und Schwingungstechnik im DIN und VDI (Acoustics, Noise Control a
8、nd Vibration Engineering Standards Committee in DIN and VDI), Working Committee NA 001-03-06-01 (NALS/VDI C 6.1) Auswuchten und Auswuchtmaschinen. Attention is drawn to the possibility that some of the elements of this document may be the subject of patent rights. DIN and/or DKE shall not be held re
9、sponsible for identifying any or all such patent rights. The DIN Standards corresponding to the International Standards referred to in this document are as follows: ISO 1925 DIN ISO 1925 IEC 60034-14 DIN EN 60034-14 (VDE 0530-14) The German standards are listed in the National Annex NA. ISO 21940 co
10、nsists of the following parts, under the general title Mechanical vibration Rotor balancing: Part 1: Introduction1) Part 2: Vocabulary2) Part 11: Procedures and tolerances for rotors with rigid behaviour3) Part 12: Procedures and tolerances for rotors with flexible behaviour4) Part 13: Criteria and
11、safeguards for the in-situ balancing of medium and large rotors5) Part 14: Procedures for assessing balance errors6) Part 21: Description and evaluation of balancing machines7)1) Revision of ISO 19499:2007, Mechanical vibration Balancing Guidance on the use and application of balancing standards 2)
12、Revision of ISO 1925:2001, Mechanical vibration Balancing Vocabulary 3) Revision of ISO 1940-1:2003 + Cor.1:2005, Mechanical vibration Balance quality requirements for rotors in a constant (rigid) state Part 1: Specification and verification of balance tolerances 4) Revision of ISO 11342:1998 + Cor.
13、1:2000, Mechanical vibration Methods and criteria for the mechanical balancing of flexible rotors 5) Revision of ISO 20806:2009, Mechanical vibration Criteria and safeguards for the in-situ balancing of medium and large rotors 6) Revision of ISO 1940-2:1997, Mechanical vibration Balance quality requ
14、irements of rigid rotors Part 2: Balance errors 7) Revision of ISO 2953:1999, Mechanical vibration Balancing machines Description and evaluation Part 23: Enclosures and other protective measures for balancing machines8) Part 31: Susceptibility and sensitivity of machines to unbalance9) Part 32: Shaf
15、t and fitment key convention10)Amendments This standard differs from DIN ISO 8821:1991-10 as follows: a) the number of the standard has been changed; b) statements relating to the implementation date, transition period and key convention usage in the past have been deleted; c) the standard has been
16、editorially revised and updated. Previous editions DIN ISO 8821: 1991-10 National Annex NA (informative) Bibliography DIN EN 60034-14 (VDE 0530-14), Rotating electrical machines Part 14: Mechanical vibration of certain machines with shaft heights 56 mm and higher Measurement, evaluation and limits o
17、f vibration severity DIN ISO 1925, Mechanical vibration Balancing Vocabulary 8) Revision of ISO 7475:2002, Mechanical vibration Balancing machines Enclosures and other protective measures for the measuring station 9) Revision of ISO 10814:1996, Mechanical vibration Susceptibility and sensitivity of
18、machines to unbalance 10) Revision of ISO 8821:1989, Mechanical vibration Balancing Shaft and fitment key convention 4 DIN ISO 21940-32:2012-08 Introduction It is often impossible or economically unreasonable to balance rotors with fitments after they have been assembled; the rotor components which
19、also may originate from different suppliers are therefore balanced separately. An appropriate balance tolerance is applied to each component so that, when shaft and fitment(s) are coupled together, the rotor assembly meets the required balance tolerance and/or vibration limit. For coupling the fitme
20、nt(s) to the shaft, different methods are applied, a very common one uses keys. If, however, a different key convention has been used when balancing the shaft than that one used for balancing the fitment(s), it is quite likely that the rotor assembly has a balance error influencing its residual unba
21、lance. There are three methods, or key conventions, for balancing shafts and fitments coupled together with keys: full-key convention; half-key convention; no-key convention. This part of ISO 21940 unifies the key conventions used throughout the world and gives instructions on a marking of component
22、s balanced in accordance with the key convention applied. When consistently used, it results in compatibility of shafts and fitments so that they can be balanced by different suppliers and, after being assembled, the balance tolerance and/or vibration limit for the rotor assembly is met. 5 DIN ISO 2
23、1940-32:2012-08 1 Scope This part of ISO 21940 specifies one convention for balancing the individual components (shaft and fitments) of a keyed rotor assembly. This provides compatibility of all balanced components so that when they have been assembled the overall balance tolerance and/or vibration
24、limit for the rotor assembly is met. This part of ISO 21940 specifies that half-keys be used when balancing the individual components of a keyed rotor assembly. It also specifies a marking of the components balanced in accordance with the key convention used. This part of ISO 21940 applies to rotors
25、 balanced in a balancing machine, in their own bearings or in situ. The key convention can also be applied when measuring the residual unbalance and/or vibration of rotors with keyways, but to which fitments have not yet been assembled. In addition to applying to keys of constant rectangular or squa
26、re cross-section mounted parallel to the shaft centreline, this part of ISO 21940 also applies to keys mounted on tapered shaft surfaces, to woodruff, gibhead, dowel and other special keys. The principle of the half-key convention is applied as is appropriate to the particular shape and location of
27、the special key. 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 1925,
28、 Mechanical vibration Balancing Vocabulary1)3 Terms and definitions For the purposes of this document, the terms and definitions given in ISO 1925 apply. 4 Half-key convention This part of ISO 21940 specifies that the half-key convention be followed. According to this convention a half-key shall be
29、used in the keyway of the shaft having one keyway while balancing the shaft without the fitment. A complementary half-key shall be used while balancing the corresponding fitment on a balancing mandrel, provided the mandrel has no keyways. If the mandrel has keyways, the methods described in A.1.3 sh
30、all be followed. If at one cross-section, shaft and fitment each have two keyways the methods described in A.1.4 shall be followed. The axial location of the centre of gravity of the half-key should be the same as that of the full key in the final assembly. NOTE Table 1 shows examples of various typ
31、es of shaft keyways and full keys of constant rectangular or square cross-section. 1) To become ISO 21940-2 when revised. 6 DIN ISO 21940-32:2012-08 Table 1 Examples of types of shaft keyways and keys Type Configuration of keyway Name of keyway Configuration of keyaName of key A Round/round end Squa
32、re/square endRound/round end B Round/square end Round/square end Square/square endRound/round end C Sled runner Square/square enda Full-key cross-section Rectangular Square l Length of the keyway d Depth of the keyway 7 DIN ISO 21940-32:2012-08 Practical considerations for making and usage of half-k
33、eys are given in Annex B. A contoured half-key set is shown in Figure 1. Key 1 half-key for the fitment 2 half-key for the shaft Figure 1 Contoured half-key set The use of the half-key convention provides a uniform method for balancing shafts and fitments joined together by keys. It eliminates balan
34、ce errors and therefore unnecessary residual unbalance and/or vibration which can be caused by the use of different key conventions, and avoids the creation of an internal bending moment in the assembly (as would be caused by the use of full keys during balancing of the shaft). For more information
35、on the differences between the key conventions, see Annex C. 5 Marking 5.1 The end face of the shaft adjacent to the keyway shall be permanently marked with the letter H to indicate that balancing was performed using the half-key convention. Permanent marking using metal stamps or vibratory engraver
36、s is recommended, but a permanent or indelible ink may also be used. If the shaft end face is too small for marking, the bottom of the keyway may be used. 5.2 The face of the fitment adjacent to the keyway shall be permanently marked with the letter H to indicate that balancing was performed using t
37、he half-key convention. The letter should be readily visible when the fitment is joined to the shaft. Permanent marking using metal stamps or vibratory engravers is recommended, but a permanent or indelible ink may also be used. 5.3 The marking of the shaft and the fitment with the letter H may only
38、 be omitted if confusion as to which key convention was used is unlikely. 5.4 When balancing a replacement shaft or fitment, the known mating part of which has not been balanced using the half-key convention, it is permissible to balance the replacement component with the key convention of the exist
39、ing mating part. In this special case, both components shall be permanently marked with an identification letter corresponding to the key convention used, as follows: a) components balanced using the full-key convention (see C.1.2) shall be marked with the letter F adjacent to the keyway; 8 DIN ISO
40、21940-32:2012-08 b) components balanced using the no-key convention (see C.1.4) shall be marked with the letter N adjacent to the keyway. NOTE 1 For the fitment, the balancing procedures in accordance with the full-key convention and the no-key convention are identical. Marking is done as ordered. N
41、OTE 2 If fitments are balanced for being put on stock, these fitments may be marked either with F or with N. But since the full-key convention is in use more often, these fitments generally are marked with F. 6 Implementation of the half-key convention All manufacturers of original parts and process
42、ed components shall comply with the half-key convention of balancing and mark each newly manufactured shaft and fitment with the letter H. NOTE Some International Standards prescribe that the half-key convention be followed, e.g. IEC 60034-141. Change-over of equipment in service to the half-key con
43、vention with proper marking of the shaft and fitment(s) during a repair balancing operation is encouraged. In any case, a marking shall be added (see Clause 5). 9 DIN ISO 21940-32:2012-08 Annex A (normative) Specifications for the half-key convention A.1 Principal specifications for the half-key con
44、vention A.1.1 The specifications given in A.1.2 to A.1.4 apply to one cross-section. A.1.2 For a shaft with a single keyway, a half-key is required for the keyway. A.1.3 For a fitment with a single keyway, one of the following requirements shall be met: a) when the mandrel has no keyway: use one hal
45、f-key; b) when the mandrel has two identical keyways 180 opposite each other: use one full key and one half-key of equal length; c) when the mandrel has a single keyway: first use one half-key for balancing the mandrel, and then use one full key for balancing the mandrel/fitment assembly. NOTE 1 Man
46、drel constructions using requirement a) or b) are preferred because they are inherently balanced. NOTE 2 The balancing mandrel should have the same diametral tolerances as the shaft it is intended to simulate. The mandrel should also have correction planes on it to allow for unbalance correction, in
47、dex balancing and biasing. A.1.4 If a shaft or fitment is provided with two equal keyways 180 opposite each other and two keys are used in the final assembly, it is permissible to balance without keys. This is in accordance with the specifications for the half-key convention. If the two keyways are
48、not equal or are positioned other than 180 opposite each other, two half-keys are required for balancing the shaft and two more for balancing the fitment. A.1.5 Special keys, such as woodruff, gibhead or tapered keys, require individual consideration. A.1.6 If a full key is shipped with the shaft, its length is obvious and therefore permits determination of the proper half-key length for balancing the fitment (see also B.4). If no key is shipped with the shaft, the length of t
