The scheduled arrival at chennai is 22:15 hrs. The journey from Katpadi to Chennai is pretty bad. 3 and half hours allotted to cover 130 km. Lot of slack time is allotted for various crossings (Kovai Exp, Brindavan exp etc). From perambur to Chennai Central as per time table almost 2 hours time is given as slack !!!!! Also i think the time between 8pm-10pm, chennai station is packed with trains starting and terminating ...hence its arrival is kept after 22:15. It can easily be speeded up by 1.5 hours