By jacketed pipe I assume you mean a pipe within a pipe? Also when you say design basis are you talking pipe design or steam trap set up.
Anyway here is a picture for a steam trap set up for a traced line from the Spirax Sarco site, if this is what you are after then it would be the same for a "jacketed" pipe.
The Spirarx Sarco <usual disclaimer> website is a very well-known publication.
__________________
"Did you get my e-mail?" - "The biggest problem in communication is the illusion that it has taken place" - George Bernard Shaw, 1856
"Almost" Good Answers: