请高手指点RT1,RT2,RT3,RT4怎么理解?

Henry88842110

RT1是100%RT，RT3是SPOT RT. RT2是在RT1的基础上增拍按照UW11-A(5)b.是由于出现了T头。筒体在成型时做100%RT，在成型后开孔时接管，正好位于A\B缝时需要对该重合的AB焊缝做SPOT RT。我们俗称增拍。其实ASME标准修改时放宽了，我记得老标准开孔离得很近还没落上去就要增拍。开孔影响区扫过的AB缝就要做。1998版的GB150的容器开孔影响区完全照抄ASME。以开孔直径的1.5倍为半径画圆。RT4是以上都不适用。

yangyangshu

请见ASME BPVC VIII-1,  UG-116 REQUIRED MARKING （e）.

这里面已经规定得非常清晰了。

(e) When radiographic or ultrasonic examination has been performed on a vessel in accordance with UW-11, marking shall be applied under the Certification Mark as follows:
按UW-11 规定进行射线检测或超声波检测的容器应在认证标志下面，按下面规定进行标志：

(1) “RT 1” when all pressure-retaining butt welds, other than Category B and C butt welds associated with nozzles and communicating chambers that neither exceed NPS 10 (DN 250) nor 11/8 in. (29 mm) wall thickness [except as required by UHT-57(a)], satisfy the full radiography re-quirements of UW-11(a) for their full length; full radiography of the above exempted Category B and C butt welds, if performed, may be recorded on the Manufacturer’s Data Report; or
除连接不超过NPS 10 (DN 250)及壁厚不超过1-1/8 in. (29mm)的接管和连通室的B 和C 类对接焊缝之外［UHT - 57 (a)要求的除外］，所有承压对接焊缝全长满足UW -11(a)的全部射线检测要求，则标志“ RT l ”；如果上述免除的B 和C 类对接焊缝进行了全部射线透照检测，也可记录在制造商数据报告上；或

(2) “RT 2” when the complete vessel satisfies the requirements of UW-11(a)(5) and when the spot radiography requirements of UW-11(a)(5)(-b) have been applied; or
完工容器满足UW -11 (a)(5)的要求。及按UW-11(a)(5)的要求进行抽样射线验，则标志“RT 2”；或

(3) “RT 3” when the complete vessel satisfies the spot radiography requirements of UW-11(b); or
完工容器满足UW-11(b)抽样射线检验的要求，则标志“RT 3”；或

(4) “RT 4” when only part of the complete vessel has satisfied the radiographic requirements of UW-11(a) or where none of the markings “RT 1,” “RT 2,” or “RT 3” are applicable.
只有完工容器的部分满足UW-11(a) 射线照相检验要求，或标注““RT 1,” 、“RT 2,”或““RT 3”都不合适，则标志“RT 4”。

The extent of radiography and the applicable joint efficiencies shall be noted on the Manufacturer’s Data Report. 射线检测比例及相应的接头系数应在制造商数据报告上予以注明。