射线检测作业指导书RT Operation Specification（中英对照）

1、第三方nde检测单位the third party inspection organizationrt作业指导书rt operation specification目 录1.检测范围scope of testing12.防护precautionary measures13.检测人员ndt personnel14.透照方式ways of radiographing25.表面要求surface requirements26.定位标记和识别标记position and identification marks37.象质计image quality indictor38.射线透照质量等级39.胶片和增

2、感屏films and intensifying screens410.几何条件geometry511.无用射线和散射线的屏蔽shielding of unwanted rays and scattering rays612.曝光exposure713.胶片处理film processing714.底片质量negative quality715.底片的观察observation of films916.焊缝射线透照缺陷等级评定16 defect rating of weld radiography917.报告及验收标记17 reports and acceptance91. 检测范围scope

3、 of testing1.1. 本章依据jb4730承压设备无损检测the guidelines are written in accordance with jb4730 nondestructive testing of pressure equipments.1.2. 本章规定了在焊缝透照检测过程中，为获得合格透照底片所必须遵循的程序和要求。the guidelines stipulate the procedures and requirements that must be followed in performing radiographic testing of welds in

4、 order to obtain satisfied films.1.3. 本章适用于碳素钢、低合金钢、不锈钢焊缝及钢管对接环缝的射线透照检测。the guidelines are applicable to the radiographic testing of the welds including those of carbon steels, low alloy steels and stainless steels and circumferential welds of butt-jointed steel pipelines.2. 防护precautionary measures

5、2.1. x射线对人体有不良影响，应尽量避免射线的直接照射和散射线的影响。x-ray is detrimental to human health. avoid direct exposure and the influence of scattering rays.2.2. 从事射线检测的人员应备有剂量仪或其它剂量测试设备，以测定工作环境的射线照射量和个人受到的累计剂量,单个剂量仪要包括一个tlv标志，记时读数剂量计和声音警报仪。ndt personnel should equip with dose meters or other dose measuring devices in ord

6、er to determine the amount of exposure in working environment and accumulative dosage of individuals, individual dosimeters will inchude a tlv badge (cumulative),an instant reading dosimeter and audible alarm dosimeter.2.3. 在现场进行射线检测时应设置安全线.安全线上应有明显警告标志,夜间应设红灯,人工剂量计不能用于射线边界监控区域。safety bands with int

7、ermational radiation warning signs shall be provided when performing in situ testing. red flushing lights should be provided in night operation,personal dosimeters shall not be used for monitoring area radiation boundaries.2.4. 检测人员每年允许接受的最大射线照射剂量为510-2sv，非检测人员每年允许接受的最大剂量为510-3sv。for ndt personnel,

8、the maximum allowable exposure is 510-2sv per year. for non-ndt personnel, the maximum allowable exposure is 510-3sv per year.3. 检测人员ndt personnel3.1. 凡从事无损检测的人员，都必须经过技术培训， 并按照无损检测人员资格认可规则(1995)及gb9445进行考核鉴定。personnel engaging in ndt shall have received technical trainings and passed qualification t

9、ests in accordance with rules of certification for ndt personnel (1995) and gb9445 national standard.3.2. 取得不同无损检测方法的各技术等级人员，只能从事与该等级相应的无损检测工作，并负相应的技术责任。technicians who have passed certain levels of ndt qualification tests should perform ndt tasks equivalent to that level and be liable to such respo

10、nsibilities.4. 透照方式radiography technics4.1. 按射线源、工件和胶片三者间的相互位置关系，透照方式分为纵缝透照法、环缝外透法、环缝内透法、双壁单影法和双壁双影五种，见图1-1。in view of the interposition of radiation source, weldment and film, there are five ways of radiographing: longitudinal weld radiography, circumferential weld radiography from outside, circumf

11、erential weld radiography from inside, dual walls single projection and dual walls dual projections. see picture 1-1.射线源射线源 射线源射线源 胶片胶片 c1 胶片 ( a ) ( b ) ( c ) c2 (a)纵缝透照法 (b)环缝外透法 注：c1射线源不在部件中心；c2 射线源在部件中心。(a) longitudinal weld (b) (b) circumferential weld from outside (c) circumferential weld from

12、 inside (note: c1: radiation source is not placed at the center of the weldment; c2: radiation source is placed at the center of the weldment.) 射线源射线源胶片胶片 ( d ) ( e )(d)双壁单影法 (e)双壁双影法(c) dual walls single projection (d) (e) dual walls dual projections图1-1 透照方式示意图figure 1-1 illustrations of radiograp

13、hy technics5. 表面要求surface requirements5.1. 焊缝的表面质量(包括焊缝余高)应经外观检查合格，表面的不规则状态在底片上的图像应不掩盖焊缝中的缺陷或与之相混淆，否则应做适当的修理。surface quality of the weld (including excess weld metal) should pass the appearance check. images on the films derived from surface irregularities should not conceal defects in the weld or c

14、onfuse with them. or surface preparation is needed.6. 定位标记和识别标记position and identification marks6.1. 定位标记： 焊缝透照部位应有搭接标记()，如有需要也可放置中心标记( )。当抽查时搭接标记称为有效区段标记。position marks：a lapped mark() ,or a centre mark ( ) when necessary, should be placed on the part of the weldment to be radiographed. in spot-che

15、ck, the lapped mark is referred as the “effective zone” mark.6.2. 识别标记： 被检的每段焊缝附近应贴有下列铅质识标记：产品编号、焊缝编号、部位编号和透照日期。返修透照部位还应有返修标记r1、r2(其数码1、2指返修次数)。identification marks：every section of welds to be examined should have the following lead marks beside it: product number, weld number, position number and

16、date of radiographing. parts that returned for repair should have repair marks like r1, r2 (number 1, 2 refer to the times of repair.)6.3. 标记位置：上述定位标记和识别标记均应放在胶片的适当位置，并离焊缝边缘至少5mm；搭接标记的安放位置见附录a。placement of marks：the above-mentioned position and identification marks should be placed on suitable posit

17、ions on the film and at least 5mm away from the edge of the weld. see appendix for the placement of lapped marks.6.4. 工件表面应作出永久性标记，以作为对每张底片重新定位的依据。产品上不适合打印标记时，应采用详细的透照部位草图和其它的有效方式标注。surfaces of the weldments should have permanent marks for relocation of films. if not suitable to stamp marks on the s

18、urfaces, a detailed draft of the part to be radiographed should be provided or other effective means of marking be adapted.7. 象质计image quality indictor7.1. 象质计是用来检查透照技术和胶片处理质量的，衡量质量的参数是象质指数，它等于底片上能识别出的最细金属丝的线编号。image quality indictor is used to measure the level of radiographic technique and the qua

19、lity of film processing. the parameter used to measure quality is image quality index, which is equivalent to the number of the smallest metal wire that can be identified on the negative.7.2. 象质计的放置：线型象质计应放在射线源一侧的工件表面上、被检焊缝区的一端，金属丝应横跨焊缝并与焊缝方向垂直，细丝置于外侧。当射线源一侧无法放置象质计时，也可放在胶片一侧的工件表面上，但象质计指数应提高一级或通过对比试验

20、，使实际象质指数达到规定的要求。象质计放在胶片一侧工件表面上时，应附加“f”标记以示区别。position of the image quality indictor：wire-type image quality indictor should be placed on the weldment surface at the same side with the radiation source and at one end of the weld zone to be tested. metal wires should traverse across the weld and are p

21、erpendicular to the welding direction. wires of smaller diameters are placed on the outer side. when it is impossible to place the indictor at the same side with the radiation source, the indictor may be placed on the weldment surface at the same side with the film. in such case, quality index shoul

22、d increase 1 grade correspondingly. or that the actual quality index reach the requirements should be made sure by comparison tests. when the indictor is placed on the weldment surface at the same side with the film, “f” mark should be attached to the indictor to show difference.8. 射线透照质量等级射线透照质量等级分

23、为a级(普通级)、ab级(较高级)和b级(高级)。不同材料不同厚度的工件采用a级、ab级或b级时，在射线底片上必须显示的最小象质计线径及相应的象质指数见表1-1。quality of radiography is measured in three grades: a grade(common); ab grade(higher) and b grade(highest). to weldments of different materials and thickness, when a, ab or ab grade of quality is needed, the smallest di

24、ameter of wires that must be showed on the negative and its relative image quality index are summarized in table 1-1.表1-1 象质计的选用table 1-1 selection of image quality indictor要求达到的象质指 数 zrequire image quality indexz线 径mmwire diametermm适合的透照厚度 ta (mm)suitable radiographed thickness ta (mm)a型a gradeab型a

25、 bgradeb型b grade161514131211109876543210.1000.1250.1600.2000.2500.3200.4000.5000.6300.8001.0001.2501.6002.0002.5003.2006688101016162525323240406060808015015017017018018019019020066881212161620202525323250508080120120150150200200250668810101616252532324040505080801501502002002509. 胶片和增感屏films and int

26、ensifying screens9.1. 胶片的分类和选择：工业x射线胶片的类型见表1-2。通常，如需缩短曝光时间，则需使用表1-2中号数较大的胶片；如需提高射线透照的底片质量，则需使用号数较小的胶片。types of films and film selections：table 1-2 is three types of film for industrial x-ray. generally speaking, if shorter exposure time is desired, films of bigger figures should be used. if you want

27、 to improve image quality, films of smaller figures are needed.表1-2 工业射线透照胶片的类型table 1-2 types of industrial x-ray films胶片型号film model速 度speed反 差contrast粒 度fineness123低low中medium高high高high中medium低high细good中medium粗bad9.2. 增感屏：金属增感屏按表1-3选用。intensifying screens：follow table 1-3 for the selection of met

28、al intensifying screens.表1-3 增感屏的选用table 1-3 selection of intensifying screens射线种类type of ray增感屏材料material of intensifying screen前屏厚度mmfront screen thickness mm后屏厚度mmrear screen thickness mm120-250kv250-450kvir192铅箔 lead foil 铅箔 lead foil 铅箔 lead foil 0.025-0.1250.05-0.160.05-0.160.100.100.6010. 几何条

29、件geometry10.1. 一次透照长度是指采用分段曝光时，每次曝光所检测的焊缝长度，应符合相应透照质量等级的黑度和象质指数规定。one radiographic length refers to the length of weld that can be tested in every exposure when multi-sectional exposure is adapted. requirements for densities corresponding to radiographic quality grade and image quality index should

30、be satisfied.10.2. 焊缝的透照厚度比k，按图1-2和式1-1来确定，环缝的a级和ab级的k值不大于1.1，b级的k值不大于1.06；纵缝的a级和ab级的k值不大于1.03，b级的k值不大于1.01。焊缝透照厚度比为：radiographic thickness rate of weld “k” is determined according to figure 1-2 and formula 1-1. for a grade and ab grade of circumferential welds, values of “k” do not exceed 1.1, whil

31、e for b grade, the value of “k” do not exceed 1.06. for a grade and ab grade of longitudinal welds, values of “k” do not exceed 1.03, while for b grade, the values do not exceed 1.01. radiographic thickness rate of weld is： k = t t （1-1）式中：t-母材厚度，mm；which t-thickness of base metal, mm；t-射线束斜向透照最大厚度，

32、mm。 t-maximum thickness that the oblique ray beam can penetrate, mm 射线源radiation source t t图1-2 焊缝透照厚度比示意图图1-2 illustration of thickness rate10.3. 透照时射线束应指向被检部位的中心，并在该点与被检区平面或曲面的切面垂直。如需要，也可从有利于发现缺陷的其它方向进行透照。当采用双壁透照法时，一般应使射线偏离焊缝轴线所在的平面进行斜透照，以免两侧焊缝影象重叠。in radiography, ray beam should point to the cent

33、er of the weldment to be tested and be perpendicular to the section of the flat or curved plane of the tested area. in case of necessity, radiography can be done from other directions that facilitate the finding of defects. when double walls radiography is used, the rays should deviate from the plan

34、e where the axis of the weld is and shoot obliquely to the weldment so that the images of the welds on both walls would no overlap.10.4. 透照厚度应按附录b确定。radiographic depth should be decided according to appendix b.11. 无用射线和散射线的屏蔽shielding of unwanted rays and scattering rays11.1. 为减少散射线的影响，应采用适当的屏蔽方法以限制

35、受检部位的受照面积。为避免从其它工件或胶片后方和侧面物体上产生的散射线对胶片的影响，可采用加厚增感屏,或在胶片与增感屏后再加上一块铅板，其厚度约1-4mm。to reduce the influence of scattering rays, proper means of shielding should be adapted to restrict the area radiographed on the weldment. in order to avoid influence to the films caused by scattering rays emitting from ot

36、her weldments or objects behind and beside the films, intensifying screens can be used or a lead plate with 1-4mm thickness can be inserted between films and the intensifying screen.11.2. 为检查背散射，可在暗盒背面贴附一个“b”的铅字标记(其高度为13mm，厚度为1.6mm)。若在较黑背景上出现“b”的较淡影象，就说明背散射线保护不够，应采取有效措施重照。如在较淡背景上出现“b”的较黑影象，则该底片不能作为评

37、判的依据。to check backscattering, a “b” lead mark with 13mm high and 1.6mm thick can be attached on the rear side of the x-ray cassette. if a lighter “b” image appears in the darker backdrop, it shows that backscattering rays are too strong. in such case, effective measures should be taken and radiograp

38、hic task should be repeated. if a darker “b” image appears in the lighter backdrop, this negative should not be used for evaluation.12. 曝光exposure12.1. 应根据设备、胶片、增感屏和其他具体条件制作或选用合适的曝光曲线.并以此确定曝光规范。based on your equipment, film, intensifying screen and other practical conditions, decide and select the s

39、uitable curve of exposure so as to determine exposure requirements.12.2. 为达到规定的底片黑度，推荐采用不低于15mamin的曝光量，以防止用短焦距和高电压所引起的不良影响。in order to reach the required densities on negatives, exposure15mamin is recommended to prevent unfavorable influences caused by short focal length and high voltage.13. 胶片处理fil

40、m processing13.1. 胶片的处理应按胶片的使用说明书。采用手工冲冼方式或自动冲洗。follow the user manual of films in film processing. manual or automatic development can be used.13.2. 胶片的手工冲冼应采用槽浸方式，在规定温度(20左右)和时间内进行显影、定影等操作。定影后的底片应经充分水洗和洗涤剂处理，以防止水迹的产生，然后自然干燥或在干燥箱内烘干，显影剂要根据中华人民共和国环境有关规定处理好。when films are developed manually, they sho

41、uld be developed and fixed in specific temperature (about 20) and time by immersing them into a processing trough. negatives after fixation should be washed by adequate water and treated by detergents to avoid forming of water traces. then these negatives are dried naturally or by drying oven,all de

42、veloping chemicals shall be disposed of in accordance with relative prc environmental regulations.14. 底片质量negative quality14.1. 象质指数：底片上必须显示出的最小线径及象质指数见表1-1。image quality index：the diameter of smallest wire that must be displayed on the negative and image quality index are showed in table 1-1.14.2.

43、黑度：选择的曝光条件应使底片有效评定区域内的黑度均满足表1-4的要求。density：exposal conditions chosen should be able to guarantee that densities in the effective rating zone on the negative meet the requirements in table 1-4.表1-4 底片的黑度范围table 1-4 density ranges of negative射线种类type of ray底片黑度 dnegative density d灰雾度 d0fog density d0x

44、射线x-raya级a level1.2-3.5 0.3ab级ab levelb级b level1.5-3.5射线gamma ray1.8-3.5 0.3注：表中d值包括了d0值。note: d values include d0 values.14.3. 影像识别要求requirements for image identification14.3.1. 底片上的像质计影像位置应正确，定位标记和识别标记齐全，且不掩盖被检焊缝影像。image quality indictor should be on the correct position on the negative. position

45、and identification marks should be both visible and do not cover up the image of the weld radiographed.14.3.2. 在黑度一致的范围内，应能清晰地看到长度不小于10mm的像质计金属丝影像。in area of the same density, image with length no less than 10mm produced by metal wire of the image quality indictor should be clearly visible.14.4. 不允许

46、的假缺陷： 在底片评定区域内不应有以下妨碍底片评定的假缺陷。unallowable artifacts：the following artifacts that could disturb evaluation process are not allowed to appear in the negative rating zone.14.4.1. 灰雾；fog；14.4.2. 处理时产生的条纹、水迹或化学污斑等缺陷； stripe, water trace and chemical blotch caused in film processing；14.4.3. 划痕、指纹、赃物、静电痕迹、

47、黑点或撕裂等；scratch, fingerprint, dirt, static trace, macula or tear；14.4.4. 由于增感屏不好造成的缺陷显示。defect caused by bad performance of intensifying screen15. 底片的观察observation of films15.1. 评片环境：评片应在专用评片室内进行。评片室内的光线应暗淡，但不全暗，室内照明用光不得在底片表面产生反射。observation environment films should be observed in a special room dedi

48、cated for that purpose. it should be dim in the room but not totally dark. the lighting should not cause reflection on the surface of films. 15.2. 观片灯：观片灯最大亮度应不小于100,000cd/m2，且观察的漫射光亮度应可调。对不需要观察或透光量过强的部分应采用适当的遮光板屏蔽强光。经照明后的底片亮度应不小于30cd/m2。observation lamp the maximum brighness of the lamp should be n

49、o less than 100,000cd/m2 and the brightness of observable diffuse lights should be able to be adjusted. suitable shading plates should be used to cover those parts that need not to be observed or allow too much light to pass. the brightness of the film after illuminated should be no less than 30cd/m

50、2.16. 焊缝射线透照缺陷等级评定defect rating of weld radiography按jb4730-1994第6条执行。defect rating is carried out according to no.6 article in jb4730-1994 standard.17. 报告及验收标记17 reports and acceptance17.1. 报告至少应包括以下内容：a report should at least include the following items:a. 委托单位、被检工件名称、编号；entrusting party, name of t

51、he weldment tested and serial number; b. 被检工件材质、母材厚度；material of the weldment tested and its thickness;c. 检测装置的名称、型号；name and model of the testing equipment;d. 透照方法及透照规范；means of radiography and its criterion;e. 透照部位及工件草图(或示意图)；part radiographed and draft of the weldment (or sketch map)；f. 检测结果及缺陷等级

52、评定；test results and defects rating;g. 返修情况；repair records;h. 检测人员和责任人员签字及其技术资格；signatures of testing technicians and responsible director and their technical qualifications;i. 检测日期。date of testing.17.2. 检测结果要符合cc规定，检测报告样本见附件。 the test result shall inform cc tinely，test report sample see the attachment.附录a 搭接标记的安放位置（补充件）appendix a position of the lapped mark（a