没理解错的话，楼主所说的是供热管道，供热管网工程的焊缝无损检验数量按规程规定数量进行即可。当使用超声波和射线两种方法进行检验时，应按各自标准检验，均合格时方可认为无损检验合格。需要特别注意的是：超声波探伤部位应采用射线检测复验，复验数量不少于超声波数量的20%。无损检测不能代替耐压试验，现场中拍片或超声波检测合格而试压时不合格的例子不少的！5 ~8 f' K+ T* L2 P) l; z
总而言之，100%的UT不能保证运行时不漏；100%的UT不能代替水压试验，而且这种做法本身就与规程不符；楼主所说的细微的贯穿裂纹超声波是不容易检验出来的，超声波检验对操作人经验的依赖性太大，这里就不好多说了。# d9 d* K/ O% V- F' L2 n4 w
ASME B31.3 Process piping -2006: 3 s8 G' k2 Q- _2 A* D4 n0 u345.9 Alternative Leak Test% f7 A+ X& f5 E, M0 X3 I _! G
The following procedures and leak test method may% u1 L" c" ^# e& z* L
be used only under the conditions stated in para.) F' N' d) w. |# l
345.1(c). : w" V: C/ [" `: ~" K345.9.1 Examination of Welds. Welds, including# e) J) e1 L+ x
those used in the manufacture of welded pipe and fittings, 2 h: \( P+ P7 swhich have not been subjected to hydrostatic or # h. K6 _" a. r; M" n4 B- S) _. W k* Mpneumatic leak tests in accordance with this Code, shall 0 h8 N2 e" N! J- H- S5 ^3 Ube examined as follows: " C/ L* E4 Z5 ^79 @1 t% [: I: d2 x$ H5 c( D! n/ r
(a) Circumferential, longitudinal, and spiral groove - _1 [4 F& P7 Y7 i, N* e* H/ e, Swelds shall be 100% radiographed in accordance with) j* r3 C5 P: G$ g4 P, n) C
para. 344.5 or 100% ultrasonically examined in accordance1 G2 a% O6 z% ]+ R0 {, x
with para. 344.6.4 q1 p7 e. q f' V* w
(b) All welds, including structural attachment welds, / z& s1 u* Z ?# Anot covered in (a) above, shall be examined using the 0 v- t) x7 R4 x" @liquid penetrant method (para. 344.4) or, for magnetic 0 o! \5 m8 }" f3 E/ M$ u9 W O5 Vmaterials, the magnetic particle method (para. 344.3).
发表于 2007-8-5 01:01:24
发表于 2007-8-5 01:21:56
发表于 2007-8-5 08:27:42
楼主