"I placed 50 barrels of diesel to start the excavator. By normal calculation, it should last 100 minutes, but it actually shows 160 minutes."

Excavator started for 2 hour, 40 minutes
Excavator R9, started by Sophia. loot is protected
Excavator R9, used by Sophia, will be available in 105 minutes
Excavator Player cooldown will expire in 190 minutes

Thanks for the bug report.  fixed in new update
fixed the rounding up error when displaying time