Joint factor

FIG. 10-164 Longitudinal and spiral-weld joint factor E. NOTE It is not permitted to increase tlie joint quality factor by additional examination for joints 1, 2, and 4a. (EjLtracted from ANSI B31.3—19S0, with petmission of the publisher, theAmetican Society of Mechanical Engineets, New York.)... 

If a welded joint factor is used equations 13.39 and 13.40 are written ... 

The ratio of the knuckle to crown radii should not be less than 0.06, to avoid buckling and the crown radius should not be greater than the diameter of the cylindrical section. Any consistent set of units can be used with equations 13.43 and 13.44. For formed heads (no joints in the head) the joint factor 7 is taken as 1.0. 

J = joint factor (if applicable), g = gravitational acceleration, 9.81 m/s2, ft = design stress for tank material, N/mm2,... 

Spot radiography for longitudinal groove welds required to have a weld joint factor, ), of 0.90 requires examination by radiography in accordance with para. IP-10.5.2 of at least 300 mm (1 ft) in each 30 m (100 ft) of weld for each welder. Acceptance criteria are those stated in Table IP-10.5 for radiography for the type of joint examined. 

E = longitudinal joint factor obtained from Table IX-3B of Mandatory Appendix IX... 

The longitudinal joint factor shall be in accordance with Mandatory Appendix IX, Table IX-3B. 

This table is split into two tables by usage Table IX-3 A, Basic Quality Factors for Longitudinal Weld Joints in Pipes, Tubes, and Fittings, Ey and Table IX-3B, Longitudinal Joints Factors for Pipeline Materials. 

This specification does not include requirements for 100% radiographic inspection. If this higher joint factor is to be used, the material shall be purchased to the special requirements of Table IP-10.5 for longitudinal butt welds with 100% radiography in accordance with Table IP-2.2.9. 

Table IX-3B Longitudinal Joints Factors for Pipeline Materials...

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