Well head won't come off

[NWWolverine]

Can't get my pressure above 28lbs and the pump runs constantly. I want to check the screen to make sure it isn't clogged but this won't come off the pipe to check it. It spins but won't come off. Any suggestions? Also, what is the brand of this fitting? The flange is broke on 1 side and needs replaced

 

[Valveman]

Must be a packer assembly. The cup leathers are tight and take a lot of pull to get them loose. Sometimes a cup of bleach down the outer tube will soften them up and make it easier to pull.