Corrected entry: At the beginning of the film, Koskov is being sent down the pipeline in the "pig". After he's been sent, and the pipeline rumbles, there is an elevated piece of pipeline that the agent looks up at - with a bend in it. The "pig" is a longish cylinder that surely cannot go around bends.
DEvans
9th Nov 2008
Correction: There are no right-angle bends in the pipe; all of the bends are gradual curves. The pig is designed to negotiate the curves in the pipe.
BocaDavie ★
The pipe has a very sharp, ninety-degree bend just before Koskov's arrival (see 00:19:55, Blu-ray). No pig of that length could possibly go around it.
DEvans