BS EN 16714-2-2016 Non-destructive testing Thermographic testing Equipment《无损检验 温度记录试验 设备》.pdf

1、BS EN 16714-2:2016Non-destructive testing Thermographic testingPart 2: EquipmentBSI Standards PublicationWB11885_BSI_StandardCovs_2013_AW.indd 1 15/05/2013 15:06BS EN 16714-2:2016 BRITISH STANDARDNational forewordThis British Standard is the UK implementation of EN 16714-2:2016. The UK participation

2、 in its preparation was entrusted to TechnicalCommittee WEE/46, Non-destructive testing.A list of organizations represented on this committee can be obtained on request to its secretary.This publication does not purport to include all the necessary provisions of a contract. Users are responsible for

3、 its correct application. The British Standards Institution 2016.Published by BSI Standards Limited 2016ISBN 978 0 580 86967 9 ICS 19.100 Compliance with a British Standard cannot confer immunity from legal obligations.This British Standard was published under the authority of the Standards Policy a

4、nd Strategy Committee on 31 August 2016.Amendments/corrigenda issued since publicationDate T e x t a f f e c t e dBS EN 16714-2:2016EUROPEAN STANDARD NORME EUROPENNE EUROPISCHE NORM EN 16714-2 August 2016 ICS 19.100 English Version Non-destructive testing - Thermographic testing - Part 2: Equipment

5、Essais non destructifs - Analyses thermographiques - Partie 2: Equipement Zerstrungsfreie Prfung - Thermografische Prfung - Teil 2: Gerte This European Standard was approved by CEN on 25 June 2016. CEN members are bound to comply with the CEN/CENELEC Internal Regulations which stipulate the conditio

6、ns 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-CENELEC Management Centre or to any CEN member. This European Standard exists in

7、 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-CENELEC Management Centre has the same status as the official versions. CEN members are the national standard

8、s bodies of Austria, Belgium, Bulgaria, Croatia, Cyprus, Czech Republic, Denmark, Estonia, Finland, Former Yugoslav Republic of Macedonia, France, Germany, Greece, Hungary, Iceland, Ireland, Italy, Latvia, Lithuania, Luxembourg, Malta, Netherlands, Norway, Poland, Portugal, Romania, Slovakia, Sloven

9、ia, Spain, Sweden, Switzerland, Turkey and United Kingdom. EUROPEAN COMMITTEE FOR STANDARDIZATION COMIT EUROPEN DE NORMALISATION EUROPISCHES KOMITEE FR NORMUNG CEN-CENELEC Management Centre: Avenue Marnix 17, B-1000 Brussels 2016 CEN All rights of exploitation in any form and by any means reserved w

10、orldwide for CEN national Members. Ref. No. EN 16714-2:2016 EBS EN 16714-2:2016EN 16714-2:2016 (E) 2 Contents Page European foreword . 4 1 Scope 5 2 Normative references 5 3 Terms and definitions . 5 4 Equipment . 5 4.1 Selection of infrared camera . 5 4.2 Classification of IR cameras . 5 4.2.1 Gene

11、ral 5 4.2.2 Temperature range 6 4.2.3 Thermal resolution. 6 4.2.4 Spatial resolution and lenses 7 4.2.5 Frame rate and temporal resolution 7 4.2.6 Operating temperature range 7 4.2.7 Storage temperature range . 7 4.2.8 Spectral filter 7 4.3 Accessories 8 4.3.1 Interchangeable lenses . 8 4.3.2 IR mir

12、rors 8 4.3.3 IR protective windows . 8 4.3.4 IR camera protective housing . 8 4.3.5 Examples of excitation sources for active thermography 8 5 Function check and traceability . 9 5.1 General remarks 9 5.2 Checks by the user 9 5.3 Additional checks by the camera supplier . 9 5.4 Frequency of function

13、 checks . 9 Annex A (normative) Parameters and measuring methods for characterizing IR cameras . 10 A.1 Instantaneous field of view (IFOV) 10 Figure A.1 Instantaneous field of view (IFOV) 11 A.2 Field of view (FOV). 12 Figure A.2 Field of view (FOV) 12 A.3 Slit response function (SRF) . 13 Figure A.

14、3 Principle for the determination of the slit response function (SRF) . 14 Figure A.4 Slit response function (SRF). 15 A.4 Hole response function (HRF) . 15 A.5 Noise Equivalent Temperature Difference (NETD) . 16 A.6 Minimum resolvable temperature difference (MRTD) 16 Annex B (informative) Examples

15、for accessories . 17 BS EN 16714-2:2016EN 16714-2:2016 (E) 3 B.1 Thermometer . 17 B.2 Moisture measuring devices . 17 B.3 Anemometer . 17 B.4 Clamp-on ammeter . 17 B.5 Cameras in the visible range 17 B.6 Endoscope . 17 Bibliography . 18 BS EN 16714-2:2016EN 16714-2:2016 (E) 4 European foreword This

16、document (EN 16714-2:2016) has been prepared by Technical Committee CEN/TC 138 “Non-destructive testing”, 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

17、 February 2017, and conflicting national standards shall be withdrawn at the latest by February 2017. Attention is drawn to the possibility that some of the elements of this document may be the subject of patent rights. CEN shall not be held responsible for identifying any or all such patent rights.

18、 EN 16714, Non-destructive testing Infrared thermographic testing consists of the following parts: Part 1: General principles Part 2: Equipment Part 3: Terms and definitions According to the CEN-CENELEC Internal Regulations, the national standards organisations of the following countries are bound t

19、o implement this European Standard: Austria, Belgium, Bulgaria, Croatia, Cyprus, Czech Republic, Denmark, Estonia, Finland, Former Yugoslav Republic of Macedonia, France, Germany, Greece, Hungary, Iceland, Ireland, Italy, Latvia, Lithuania, Luxembourg, Malta, Netherlands, Norway, Poland, Portugal, R

20、omania, Slovakia, Slovenia, Spain, Sweden, Switzerland, Turkey and the United Kingdom. BS EN 16714-2:2016EN 16714-2:2016 (E) 5 1 Scope This European Standard describes properties and requirements of infrared cameras used for thermographic testing for non-destructive testing. This document gives also

21、 examples of excitation sources, the properties and requirements are described in application standards for active thermography. 2 Normative references The following documents, in whole or in part, are normatively referenced in this document and are indispensable for its application. For dated refer

22、ences, only the edition cited applies. For undated references, the latest edition of the referenced document (including any amendments) applies. EN 16714-3, Non-destructive testing Infrared thermographic testing Part 3: Terms and definitions 3 Terms and definitions For the purposes of this document,

23、 the terms and definitions given in EN 16714-3 apply. 4 Equipment 4.1 Selection of infrared camera The infrared camera (IR camera) has to be selected according to the application and the temperature of the inspected object. IR camera relevant parameters are: spectral sensitivity; temperature range;

24、thermal resolution; spatial resolution; frame rate; temporal resolution. These parameters shall be provided by the manufacturer. 4.2 Classification of IR cameras 4.2.1 General IR cameras are classified according to detector arrangement and working principle. The classification according to the detec

25、tor arrangement is: single element detector with two-dimensional opto-mechanical scanning; line scanner with one-dimensional opto-mechanical scanning or linear array; BS EN 16714-2:2016EN 16714-2:2016 (E) 6 two-dimensional detector matrix without mechanical scanning (Focal Plane Array, FPA). Mechani

26、cal scanning is achieved by moving mirrors and/or prisms. However, the frame rate is limited due to the scanning. They are therefore less applicable to capture fast processes than FPA-cameras. The classification according to the detector working principle is: thermal detectors; quantum detectors. Th

27、ermal detectors, e.g. microbolometers or pyroelectric detectors, work at room temperature. Quantum detectors have to be cooled down to very low temperatures. Cooling is accomplished with multi-stage Peltier elements (thermo-electric), liquid nitrogen, expansion devices or refrigeration machines (Sti

28、rling engine). Quantum detectors have a higher sensitivity (specific detectivity D*) and can achieve higher frame rates than thermal detectors. IR cameras can be just imagers or radiometric calibrated devices. IR-imagers are sufficient for qualitative tasks like hot spot detection or analysis of rad

29、iation distributions. Radiometric calibrated IR-cameras allow for the measurements of radiance, temperature differences or absolute temperatures provided that object parameters, such as (but not limited to) emissivity and reflected apparent temperature are known. IR cameras are adapted to the transm

30、ission properties of the atmosphere for infrared radiation (atmospheric windows): short Wave, SW: wavelength between approx. 0,8 m and 2,0 m; mid Wave, MW: wavelength between approx. 2,0 m and 5,0 m; long Wave, LW: wavelength between approx. 8,0 m and 14,0 m. 4.2.2 Temperature range The temperature

31、range is the interval between lowest and highest measurable temperature. The range should be specified for black-body temperatures (emissivity = 1). NOTE 1 Temperature range means the total temperature range, which can consist of several partial measurement ranges that can be adjusted separately at

32、the device. NOTE 2 The use of optical components like spectral filters can alter the measurable temperature range. 4.2.3 Thermal resolution The thermal resolution describes the ability of an IR camera to resolve small temperature differences. The thermal resolution is commonly described by the noise

33、 equivalent temperature difference (NETD, see A.5). The thermal resolution depends among others on: the object temperature; the integration time or response time; the temperature range. Therefore, it shall be specified at least with indication of these values. The required thermal resolution depends

34、 strongly on the application. BS EN 16714-2:2016EN 16714-2:2016 (E) 7 NOTE Typical values for the thermal resolution for object temperatures around 300 K are 0,05 K for uncooled thermal detectors and 0,02 K for cooled quantum detectors. 4.2.4 Spatial resolution and lenses The spatial resolution desc

35、ribes the ability of an IR camera to resolve small objects or details. The spatial resolution is commonly quantified with the slit response function (SRF, see A.3), hole response function (HRF, see A.4) or the instantaneous field of view (IFOV, see A.1) which is field of view for a single detector e

36、lement. These specifications are needed to calculate the spot size diameter. They depend not only on the camera itself but also on the field of view of the lens. The spot size diameter also depends on the distance between the camera and the object. The required spatial resolution of the combination

37、IR camera / lens depends strongly on the size of the investigated object or object detail. NOTE A typical value for the horizontal viewing angle of a single detector element is 1 mrad (for a lens with a 20 field of view and a detector matrix of 320 horizontal detector elements). The minimum resolvab

38、le temperature difference (MRTD, see A.6) considers thermal as well as spatial resolution of IR cameras including the observer. The MRTD characterizes the ability of the combined system IR camera and human observer to resolve small temperature differences at small structures in relation with the who

39、le FOV (see A.2). 4.2.5 Frame rate and temporal resolution The frame rate is the number of frames which are read out from the detector per time unit. NOTE 1 If windowed frames are selected the frame rate can be higher. The maximum frame rate is limited by the read out circuit. Other parameters such

40、as (but not limited to) integration time, read out mode (integrate then read, integrate while read) and response time may also impact the maximum frame rate. Temporal and thermal resolution are closely connected. For quantum detectors, for defined object conditions highest thermal resolution is achi

41、eved with long integration times, which in turn limits the maximum frame rate. The temporal resolution of IR cameras is important for capturing moving objects (or for moving cameras) as well as fast temperature changes. NOTE 2 Typical values for frame rates are for scanning cameras with a single det

42、ector element around 30 s1, for FPA cameras with uncooled thermal detectors around 60 s1and for FPA cameras with cooled quantum detectors up to 300 s1for full frames and up to 70 000 s1for windowed frames. 4.2.6 Operating temperature range The operating temperature range is the intended ambient temp

43、erature range for operating the camera. The operating temperature range is provided by the manufacturer of the camera. 4.2.7 Storage temperature range The storage temperature range is the intended ambient temperature for storing the camera. The storage temperature range is provided by the manufactur

44、er of the camera. 4.2.8 Spectral filter Spectral filters limit the spectral sensitivity range of IR cameras. They are used to adapt the camera to material specific emission or absorption properties and/or adjust the temperature measurement range. BS EN 16714-2:2016EN 16714-2:2016 (E) 8 In many cases

45、 MW cameras are used for analysing material properties because many absorption and transmission bands lay within the wavelength range between 2 m and 5 m. Examples are measurements through/on glass, plastics, flames, gases, etc. The absorption and transmission bands should be known beforehand so tha

46、t the right filters can be chosen. 4.3 Accessories 4.3.1 Interchangeable lenses Interchangeable lenses are used to adapt the camera system to specific spatial requirements of measurement tasks (image area, required minimal spatial resolution, working distance). There are standard lenses, e.g. wide a

47、ngle and telephoto lenses as well as accessory lenses for the measurement of small objects. For calibrated cameras the calibration process shall include each lens together with the camera. 4.3.2 IR mirrors IR mirrors are flat highly polished metal surfaces that reflect infrared radiation. They are u

48、sually used for imaging of inaccessible objects or object parts. 4.3.3 IR protective windows IR protective windows consist of materials with good transmission properties for infrared radiation. They are used to protect the lens from mechanical and/or chemical damage or high environmental temperature

49、s. 4.3.4 IR camera protective housing Protective housings protect IR cameras against extreme environmental conditions like: heat; dust; water; aggressive chemical substances; strong magnetic and electric fields; mechanical damage; explosive atmospheres. 4.3.5 Examples of excitation sources for active thermography 4.3.5.1 Flash lamps Flash lamps heat up the surface of the investigated object with very short light pulses (pulse thermography). 4.3.5.2 Lamps, LED and laser Lamps, LED and laser are used