Can I span a gap between pipes with heat tape?
There are 2 types of heat tape the self regulating type can be in open air and even cross over itself. This type changes its resistance based on temp so it won’t overheat.
The current based type more similar to lots of small resistors creats heat and depending on brand most can not handle non contact or wrapping on top of itself.
I would verify what the manufacturer states as things may of changed since I started purchasing self regulating heat tape about 15 years ago.
The self regulation is not the temp sensor in the cord that is used to reduce energy consumption with temps above freezing.