1、February 2009DEUTSCHE NORM English price group 11No part of this standard 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 17.160!$V b) For the
2、safety of bystanders to vibrating machines; c) For the safety of structures or buildings containing vibrating equipment; d) For the safety of people in buildings that may be subjected to intense vibration excitation; e) When there are limiting values for vibration in legislation which are exceeded.
3、5 Applicability of vibration isolation A source isolation shall be used additionally to design measures for reducing vibration; it shall not be a substitute to such measures. It can be applied a) when vibrating machines are designed or installed; b) when buildings containing vibrating machines are d
4、esigned or modified. Prior analysis of vibration phenomena and analysis of background vibration is necessary. Time history monitoring and frequency analysis for a sufficient period of time relative to the working cycle of the machine is important. Analysis of frequency response functions for the str
5、uctures that transmit and receive vibration will facilitate the “best matching“ of the structures and avoid coincidence between dominant frequencies of the source and the natural frequencies of these structures. A determination of the background vibration shall be carried out in order to know the in
6、herent vibration level below which normally no isolation is necessary. NOTE In case of correction of an existing situation, the vibration (displacement, velocity or acceleration) should be measured simultaneously on and close to the mounting points of the machine, at operators or bystanders position
7、. Measurements shall be made in the environmental conditions relevant for the location of the machine. The measurements and analysis shall help in providing an understanding of the origin of the problem and possibly give an indication of possible solutions. Measurements should be made in accordance
8、with an appropriate standard, and the standard should be identified. The mounting points of transducers and directions of measurement shall be reported. DIN EN 1299:2009-02 EN 1299:1997+A1:2008 (E) 6 In a complex situation where isolation systems are used, expert advice should be sought. The situati
9、on is especially complex when the machine and/or the supporting structure has natural frequencies (vibrational modes) in the frequency range of interest. 6 Information for the choice of an isolation system for a machine 6.1 General In order to select appropriate isolators and correctly install sourc
10、e isolation, an exchange of information is needed between the machine manufacturer, the supplier of the isolator and the machine user. The following paragraphs list the information required for an optimized machine isolation. If the machine manufacturer is also the supplier of the isolation system,
11、some of the information in the following paragraphs may seem to be not relevant. Nevertheless, some of this information may be useful when replacement parts have to be provided and should be part of the instruction handbook. The choice of the isolation system shall take into consideration not only t
12、he static characteristics of the machine, but also its dynamic characteristics (mobility) and the dynamic characteristics of its surrounding structure (and further sources). It will often be necessary for the supplier of a vibration isolation system to ask for more detailed information from the user
13、 in order to provide the best possible solution. 6.2 Information to be supplied by the machine manufacturer The manufacturer shall supply to the user of the machine as much of the following information as is needed to ensure proper installation of the machine. If necessary, he should use the support
14、 of the supplier of the vibration isolation system. 6.2.1 Physical data of the machine 6.2.1.1 Machine drawing A drawing shall be furnished giving: a) The outline and installation of the machine, if appropriate, including an intermediate foundation prescribed by the machine manufacturer; b) The over
15、all dimensions; c) The total weight and the location of the centre of gravity. Rotational inertia shall also be included. d) Specifications of bolt sizes and special connectors for securing the machine. Locations of attachments, tapped holes, tolerances and any special material considerations shall
16、be indicated on the drawing. e) Identification and direction of the three mutually perpendicular axes with origin in the centre of gravity of the unit to be isolated under conditions of preferred orientation; f) The normal machine orientation with respect to the vertical. The direction of major shoc
17、k or vibration shall be indicated. Feasible structural attachment points shall be given. These points frequently determine the isolation system in relation to orientation, centre of gravity, etc. 6.2.1.2 Vibration excitation The vibration excitation by a machine as characterised by its exciting forc
18、es and couples as a function of frequency or in form of time history shall be described in the detail necessary to ensure the safe installation and use of machinery. DIN EN 1299:2009-02 EN 1299:1997+A1:2008 (E) 7 Examples are: Inherent rotational frequency forces and couples; Residual rotational fre
19、quency forces and couples after balancing; Forces and couples caused by reciprocating masses; Torque reaction couples; Amplitudes and/or frequencies of gas pulsation phenomena; Frequencies of aerodynamic phenomena (e.g. for fans); Electromagnetic forces and frequencies associated with electrical rot
20、ating machines or transformers. 6.2.1.3 Special requirements Special features peculiar to the equipment shall be covered in the machine description and by drawings. Among such special features are a) Electrical connectors, tubing, ducting or piping which might modify the mechanical response of the m
21、ounting system (type, size, stiffness, etc); b) Externally applied forces and moments; c) Required access areas; d) Minimum clearance required for cooling air flow. Any temperature gradients which might adversely affect isolator operation shall be shown on the drawing and the expected temperature ra
22、nge shall be given. e) Maximum clearance between equipment and foundation, where applicable. 6.2.1.4 Electrical features Provisions for grounding and applicable specifications shall be indicated on the drawing, by an attached note. 6.2.1.5 Special requirements for mechanical stability Special requir
23、ements for mechanical stability shall be given. For example, special care is needed where equipment with a high or variable centre of gravity is supported by isolators located below the centre of gravity, or where uncompensated side thrusts exist. 6.2.2 Physical data of the isolation system 6.2.2.1
24、General data The supplier of the isolation system shall supply detailed information on characteristics of the isolation system: a) Type of isolation system; b) Materials of the isolation system; c) Weight of the isolation system; d) Levelling features; DIN EN 1299:2009-02 EN 1299:1997+A1:2008 (E) 8
25、e) Static stiffness of isolators; f) The maximum and minimum weight forces (expressed in Newtons) under operating conditions of the machine; g) Dimensions and location of the isolation (e.g. drawing); h) Creep of isolators relative to load and time. 6.2.2.2 Dynamic behaviour The supplier shall descr
26、ibe the translational and rotational dynamic behaviour of the isolation system in terms of dynamic stiffness. The environmental conditions and the rate of loading under which the load-deflection data were obtained shall be described and tolerances shall be given. However, where necessary, as an alte
27、rnative, the supplier can describe dynamic behaviour by transmissibility characteristics measured in a testing setup which is fully described. Dynamic behaviour may be related to variations in the following input parameters: a) Resonance frequency as a function of load; b) Amplitude; c) Temperature;
28、 d) Damping. The supplier shall describe the efficiency of isolation in the three principal directions, indicating applicable frequencies. 6.2.2.3 Durability The supplier shall present such information on durability or rather on the change of the physical characteristics as: a) Endurance limit assoc
29、iated with repeated deflections and shocks; b) Creep (permanent deformation) data, where applicable, and how the data have been obtained; c) Ageing effects due to storage in specified environments including maximum and minimum temperatures. 6.2.2.4 Environmental data The supplier shall supply the fo
30、llowing information on the isolators as necessary to ensure proper use: a) The upper and lower temperature limits beyond or below which the isolator under rated loads will not properly perform its function or will undergo permanent changes in characteristics; b) The ability of the isolator to withst
31、and corrosion or deterioration caused by such factors as humidity, water, salt spray, fungus, ozone, oils and fuels, corrosive vapours, sunshine, etc.; c) The ability to perform under adverse conditions, for example, in an atmosphere loaded with sand or dust; d) Permissible storage environment. 6.2.
32、2.5 Maintenance data The supplier shall supply details of any maintenance, periodical inspection and service requirements. DIN EN 1299:2009-02 EN 1299:1997+A1:2008 (E) 9 6.3 Information that the machine manufacturer shall require from the user 6.3.1 Technical information on the surrounding structure
33、 of the machine A brief description required for a sufficient understanding of the technical details of the proposed arrangement shall be provided. This information shall include: a) The type of structure in which the machine is to be mounted (ship, steel building, concrete building, power plant, et
34、c.); b) The location in the structure (engine room, main deck, roof, etc.); c) Data on the supporting structure (conditions of ground, e.g. permissible load of the ground, ground water level versus floor, natural frequencies and mobility of the supporting structure); d) The isolation efficiency or u
35、sers criteria for acceptance (neighbourhood, e.g. residential area, industrial area; type of neighbouring machines, e.g. testing machines, punching machines). 6.3.2 Vibration and shock situation of the surrounding structure The vibration and shock situation of the surrounding structure before the in
36、stallation of the machine shall be described with respect to the three axes by the amplitude (displacement, velocity or acceleration), corresponding frequencies and duration over which this will occur. Time history, spectral analysis, and other descriptive parameters are necessary. 6.3.3 Climatic en
37、vironment The user shall supply, as applicable, the following information on the climatic environment: a) The upper and lower temperature limits; b) Humidity, presence of water, sand or dust, salt spray, ozone, oils, solvents, radiation, etc. 7 Guidelines for the validation of isolation efficiency N
38、ormally, the supplier of isolated machines or the supplier of isolating systems has to prove the efficiency of vibration isolation in the surrounding structure of the machine. This efficiency has to be evaluated by an experimental and contractual method. Where machines are made in mass production su
39、ch evaluation may be performed under normalised installation conditions. The manufacturer shall in such cases provide information on the installation conditions which have been used for the evaluation. If relevant, a) The measurement and the evaluation of vibration have to be made before installatio
40、n as in 6.3.2. It shall be performed in contractual positions and under expected environmental conditions for the future machine; b) The measurement positions and the measurement results shall be reported; c) The acceptable values shall be communicated to the machine supplier (or machine/isolator su
41、pplier); d) The limit values accepted by the supplier shall be contractual; e) After installation, measurements shall be made at the contractual positions and conditions, using the measurement method specified and the specified processing and analysis of the results; DIN EN 1299:2009-02 EN 1299:1997
42、+A1:2008 (E) 10 f) The values measured shall be compared with the contractual limit values. NOTE In case of correction of an existing situation, the measurements are made in the same conditions as in Clause 7 in defined positions. The positions should be the positions of the disturbed subjects (oper
43、ators or workers positions, office floors, neighbouring buildings, etc.). As in Clause 7, acceptable limit values should be defined contractually between the user and the supplier. After correction, measurements should be carried out as described in Clause 7. The results should be compared with the
44、contractual values. In more complex situations more detailed measurements will be required. DIN EN 1299:2009-02 EN 1299:1997+A1:2008 (E) 11 Annex A (informative) Elements for vibration isolation A.1 Springs Springs are used to provide elastic, vibration and shock isolating supports for machines, i.e
45、. they are construction elements which deform, predominantly, elastically. Ideal springs in the theoretical sense cannot be realised in practice since each spring shows a certain amount of mass and damping. While for calculation of vibration in the frequency range of interest in this European Standa
46、rd the mass of the spring can be neglected, the damping is strongly dependent on the spring material. A.1.1 Elastomer springs Because of its elastic deformability and its small Youngs modulus, elastomers are appropriate spring materials. Compared to metal springs, elastomer springs have larger mater
47、ial damping. Deformation characteristics, such as stiffness and damping, depend on the choice of basic material and the components of the material mixture, as well as the shape of the spring. They are also affected by environmental conditions, e.g. temperature. The long-term creeping depends strongl
48、y on the composition of the material. The material has visco-elastic properties. Usually, static and dynamic stiffness of elastomer springs are different, the dynamic stiffness is greater than the static. The natural frequencies of the isolated system should be calculated only from the dynamic stiff
49、ness. With elastomer springs vertical natural frequencies of 6 Hz to 20 Hz can be achieved. In general, the load-deflection curve is non-linear but in practice for operational loading it can be linearized. The following factors are important for the load capacity and the durability of elastomer springs: a) Material and material mixture; b) Design of the spring; c) Static load, dynamic load; d) Vibration amplitude and frequency of the vibrating system. By their flexible design, the connection with metal parts, and by the wide range of possible material combinations, th
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