locking bar 14 will abut the deck surface of the hopper car 9 supporting the cover 11 in its widest open position it is possible to adjust the downward pressure imposed by the latch structure 14a on the hatch cover locking bar 14 as best shown in fig5 the hexagonal die 22 is equipped with eccentric bores 23a which are sized to accomodate the latch plate pivot 23 when the latch plate pivot 23 is removed from the die 22 the die 22 may be removed from its matching hexagonal bore 22a in latch mounting bracket 21 after removal of the die from the bore 22a the die 22 may be rotated to one of a plurality of positions wherein the die 22 fits into the hexagonal bore 22a and reinserted altering the vertical height of the bores 23a in the die 22 the latch plate pivot 23 may then be reinserted in the bore 23a in the die 22 having the vertical height desired the adjustment in the vertical location of the latch plate pivot 23 adjusts the vertical location of the cam lock member 27 when in the lock position and as a consequence alters the pressure applied via hatch cover locking bar 14 to the hatch cover 11 when the latch arrangement 14a is in the tightly sealed position as shown in fig3 it is possible to lock the latch mechanism by passing a suitable lock through the security seal bore 33 which will restrain the cam lock member handle 30 from being moved to release the hatch cover.