A bladder device for moving a component of a web packaging machine, the web packaging machine being configured to enclose a food product in a food product package made of lower and upper webs of packaging material, the bladder device comprising: a bladder; a nipple stub coupled to the bladder and having a first end configured to receive a gas and an opposite, second end configured to dispense the gas into the bladder to thereby inflate the bladder and move the component of the web packaging machine, wherein the second end has a nipple stub flange; the nipple stub having a bore configured to convey gas from the first end to the second end; a collar coupled to the nipple stub, wherein the bladder is sandwiched between the collar and the second end of the nipple stub; characterized in that one of the nipple stub flange and the collar has a depression and the other of the nipple stub flange and the collar has a boss that is oriented towards the depression such that tightening the collar on the nipple stub forces the bladder into the depression and thereby forms a fluid tight seal; wherein one of the nipple stub flange and the collar has a first sloped surface at a first side of the depression and a second sloped surface at a second side of the depression; wherein the other of the nipple stub flange and the collar has a first sloped surface at a first side of the boss that corresponds to the first sloped surface at the first side of the depression; wherein the boss is sized to fit within the depression; and wherein the nipple stub flange has a plurality of grooves formed therein that radially extend from the bore and form fluid paths along which gas freely radially flows when the bladder is deflated to thereby facilitate inflation of the bladder. a bladder; a nipple stub coupled to the bladder and having a first end configured to receive a gas and an opposite, second end configured to dispense the gas into the bladder to thereby inflate the bladder and move the component of the web packaging machine, wherein the second end has a nipple stub flange; the nipple stub having a bore configured to convey gas from the first end to the second end; a collar coupled to the nipple stub, wherein the bladder is sandwiched between the collar and the second end of the nipple stub; characterized in that one of the nipple stub flange and the collar has a depression and the other of the nipple stub flange and the collar has a boss that is oriented towards the depression such that tightening the collar on the nipple stub forces the bladder into the depression and thereby forms a fluid tight seal; wherein one of the nipple stub flange and the collar has a first sloped surface at a first side of the depression and a second sloped surface at a second side of the depression; wherein the other of the nipple stub flange and the collar has a first sloped surface at a first side of the boss that corresponds to the first sloped surface at the first side of the depression; wherein the boss is sized to fit within the depression; and wherein the nipple stub flange has a plurality of grooves formed therein that radially extend from the bore and form fluid paths along which gas freely radially flows when the bladder is deflated to thereby facilitate inflation of the bladder.