In the case of hard and abrasive media like slurry or river water in example A, a spacer ring can be installed at the bottom of the housing to reduce the clearances and to prevent larger solids from entering the stuffing box. Then the lantern ring is placed directly behind the spacer and flush water can be applied as a barrier fluid.

Example B shows the configuration for crystallizing media such as sugar, paints or plastics. Here the first three packing rings seal against the media and the flushing medium provides a barrier against the crystallizing fluid. The two packing rings on the gland side act as a secondary seal to minimize leakage from the flushing medium.

In the arrangement in example C the lantern ring is placed directly at the bottom of the stuffing box to flush with an inert gas which acts as a barrier against potentially explosive or toxic media. The following packing rings act as a safety seal.

In example D the lantern ring is used for leakage extraction in case of special or expensive media which can be re-directed into the production process.

There are also arrangements with two lantern rings in the stuffing box. For example, in high speed rotary pumps one lantern ring can be used for the supply of cooling water and the other one to extract the flush water again. But in this case the stuffing box length has to be fairly long.