API 570 states that “Temporary repairs may remain in place for a longer period of time only if approved and documented by the piping engineer.” Assuming a full encirclement sleeve has been designed for appropriate stress conditions, can “longer” be considered to be the life of the enclosed pipe?
The reason I pose the question is that hot taps are routinely installed on pipe using full encirclement tees and are typically considered permanent fittings. It seems to me that a pipe sleeve is essentially a split tee without the branch connection. In many cases, a piping system cannot be isolated without shutting down the entire refinery or installing stopples and bypasses (split tees).
I am interested to hear if anyone else has dealt with this issue at their refinery.
I appreciate any comments.
John
The reason I pose the question is that hot taps are routinely installed on pipe using full encirclement tees and are typically considered permanent fittings. It seems to me that a pipe sleeve is essentially a split tee without the branch connection. In many cases, a piping system cannot be isolated without shutting down the entire refinery or installing stopples and bypasses (split tees).
I am interested to hear if anyone else has dealt with this issue at their refinery.
I appreciate any comments.
John
