   detachInterrupt(0);
   detachInterrupt(1);
   duration = millis() - last_print_time;
-  rpm = String(revolution_count / (duration/1000) * 60);
+  rpm = revolution_count / (duration/1000) * 60;
   revolution_count = 0;
 }
 


}

void loop() {
  position_sensors();
  fluid_level_sensor();

  film_sensor();


    int i;
  if (millis() - last_print_time >= PRINT_DELAY){


    rpm_calculation();
    flow_rate();
    shaft_temp();
