Cuvintul l-am gasit in terminologia incarcatorului feroviar-sina.
"Definitia" la packing:
This operation, called surfacing, is realized by different methods, one of which is the "packing" to which this invention is related. Packing consists in the introduction, with help of special shovels or injectors, of small grade ballast, or pea gravel, underneath the crossties being worked on, while the said crossties are kept in a raised position at the. desired elevation, by appropriate hoisting equipment such as lifting jacks for example.
http://www.wipo.int/pctdb/en/wo.jsp?WO=1979/00031&IA=WO1979/...

PROCESS FOR PACKING AND LEVELING RAILWAY TRACKS AND DEVICE FOR PERFORMING THE SAME
This invention is for a highly efficient process and device for packing railway tracks by compacting ballast beneath the sleepers by a continuous forward movement along the section of the track to be packed, and comprises simultaneously performing two interdependent operations in two different zones, namely in a first zone introducing ballast beneath the sleepers and forming for said sleepers a new support surface, and in a second zone vertically tamping this support surface by applying to the rails and sleepers a vertical pulsating force.
http://www.freepatentsonline.com/3811382.html

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