open-channel
open-circuit
open-combustion-chamber
open-cut
open-cycle
open-die
open-ended
opener
open-flame
open-grained
  open-hearth
opening
opening-out
open-jawed
open-jet
open-lamp
open-link
open-loop
open-pit
open-plan
open-point

    open-hearth furnace

     мартен

     мартеновская печь