Air compressor problem

Dear Sir, We have Hitachi HiScrew22 Model=OSP-22M5WR air compressor (22 KW). We are facing some problem in it. This compressor start tripping on a long run (after to 3 to 5 hours). When compressor tripped then its not restart automatically. Then we reset overload relay manually. Then its start working but after some time compressor starts same problem on regular basis. Its condition when it trpped is Temp=85 max. Starting Ampairs=60 - Peak Ampair=75 to 80 AMP. In short run 1 to 3 hours its work properly. Some time when compressor tripped then 'Maintenance' indicator start blinking. Please help us. Thanks