In B31.3 345.2.3 (b) Flanged Joints it says:
"Flanged joints used to connect piping components and subassemblies that have previously been tested, and flanged joints at which a blank or blind is used to isolate equipment or other piping during a test, need not be leak tested in accordance with para. 345.1."
In B31.1 137.2.5 Treatment of Flanged Joints Containing Blanks it says:
"Flanged joints at which blanks are inserted to blank off other equipment during the test need not be tested after removal of the blank provided the requirements of para. 137.7.1 are subsequently performed"
Note that para. 137.7.1 is an Initial Service Test
B31.1 distinguishes between Blind Flanges and Blanks in 104.5.2 and 104.5.3, so the exclusion of hydrotesting with blind flanges seems intentional.
Does anyone know why B31.1 seems to not permit the user to bolt flanged spools together without re-hydrotesting unless they used blanks (and did an initial service test)?
"Flanged joints used to connect piping components and subassemblies that have previously been tested, and flanged joints at which a blank or blind is used to isolate equipment or other piping during a test, need not be leak tested in accordance with para. 345.1."
In B31.1 137.2.5 Treatment of Flanged Joints Containing Blanks it says:
"Flanged joints at which blanks are inserted to blank off other equipment during the test need not be tested after removal of the blank provided the requirements of para. 137.7.1 are subsequently performed"
Note that para. 137.7.1 is an Initial Service Test
B31.1 distinguishes between Blind Flanges and Blanks in 104.5.2 and 104.5.3, so the exclusion of hydrotesting with blind flanges seems intentional.
Does anyone know why B31.1 seems to not permit the user to bolt flanged spools together without re-hydrotesting unless they used blanks (and did an initial service test)?
