Definitions branch pipe

If the tangential branch pipe is designed in such a way that nap ap = then e = 0, and the calculation of CE for the tangential branch pipe can be performed in the same way as for the axial one. The only difference is in the definition of the flow spin angle. 

Di, = outside diameter of branch Ri = bend radius of welding elbow or pipe bend r = see definition in para. 304.3.4(c) and Table 10-48 r2 = mean radius of matching pipe s = miter spacing at centerline... 

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