situations adjustable bias mechanism 36 is configured for controlling a position of first seal member 34 and if present second seal member 42 relative to a respective set of end faces 24 and for providing a biasing force b between each of first seal member 34 and second seal member 42 if present and respective end faces 24 adjustable bias mechanism 36 is capable of generating the smallest possible biasing force b needed to create a suitable seal between each of first seal member 34 and second seal member 42 if present and respective end faces 24 it is advantageous to apply the smallest possible biasing force b needed to create a suitable seal as seal wear can be minimized thereby adjustable bias mechanism 36 is advantageously capable of ensuring that first seal member 34 and second seal member 42 if present are engaged when air chamber 22 is pressurized retracting end seal arrangement 26 for startup and maintenance and regulating biasing force b such that biasing force b is increased during seal break in and decreased once seated to maximize seal life the ability to retract end seal arrangement 26 when nips 20 are being closed avoids the possibility of first seal member 34 and or second seal member 42 being broken by end faces 24 catching thereon further since biasing force b is independent of chamber seal force f even if chamber seal force f is not zero end seal arrangement 26 can be closed and loaded independently of air chamber pressure as a result of such.