session Expires after 4-5 min

Question

Hi,

   We are facing issue of session expiration. There is one page which is having 40 fields to be filled before save. So this activity took around 9-10 minutes. But after filling for all data on click of Save, session expires and all data get cleared. 
   we have increased application pool recycle to 60 min still we are facing same issue.
If we put few fields and save that it works as we are saving it before 5 minutes.

  Any help appreciated.

Regards,

 VIkram Patil