"Is there any calculation we have in netbackup that says that no to used media after some amout of mount over on tapes"
Short answer is no.
Why is ths of concern to you, are you having issues with reliability ?
The number of mounts/ full passes etc ... does little to qualify tape condition, as how the tape is transported, stored, write speed (shoe shining) on average causes tape failure/ issues well before hitting any limits of max mounts / tape passes.
For example, you can take a brand new tape, and then write to it at a speed slower than the drives minimum streaming speed (known as shoe-shining). If you ran this tape constantly for 2 or 3 weeks you could cause detectable damage, with only a few mounts/ end-to-end passes.
I looked into this subject in great depth a number of years ago with the help of the tape vendor Imation. The conclusion was that the only way to detremine tape condition was to use specialist software that tracks the errors at a very low level, and can thus predict tape (or drive failure). At the time, StorSentry was a package that could do this, but I do not think it is available anymore. Some libraries (ADIC for example) have this ability built in, there may be ther software packakes available, the tape vendors should know.
Typically, companies replace all media every x years (every 3 yeras seemd to be a popular number). Interestingly, when StorSentry was used, it was found that on averge, only 3 - 4% of media needed to be replaced, not 100% ... - demonstrating I think, that the usual methods of deciding when to replace media were very very inaccurate.
Anyway, to anwer your question.
vmquery -m <media ID> will show the number of mounts a tape has undergone, and thus can be treated as a load/ unload cycle.
1 head pass is counted as the tape moves from the beginning to the very end (or from the end to the beginning).
A full tape write, is multiple head passes, as the tracks on tapes are 'linear' - thus to fill the tape, it has to write the inside tracks first, from end-to-end, then the heads move out a bit, and it writes back from end-to-beginning, and so on. The number of tape end-to-end passes required to fill a tape, depends on the tape type, for example, LTO1 has 384 tracks, the hedas can read/ write 8 tracks at a time, meaning 48 end-to-end passes are required to fill the tape.
LTO7 tapes have 3584 tracks, but here the drive can read/ write 32 at once, meaning 3584/32 = 112 end-to-end passes are requited to fully read or write the tape.
There is no way to track the end-to-end passes in NetBackup, we don't log this.
There is not really anyway to do this (unless the tape actually became full, that could be easily seen in the bptm log), but for a tape that is only partially full, before being expired and re-used it's not really possible to trace (for a start, we know how much data is sent to a drive, but not how much tape was actually used due to the tape drive doing compression).
