tour vertical à deux montants

CONT: Tours verticaux à deux montants [...] Ces réalisations correspondent habituellement à des machines de grande capacité dont le diamètre de plateau est en général supérieur à 1800 mm ou 2000 mm. Dans ce type de machine, le plateau repose sur un socle auquel sont rigidement fixés les deux montants, de droite et de gauche.

CONT: The second case [in our testing of the stability of vertical lathes] is that of a double column vertical lathe with 100 in table diameter. The first test was the comparison of stability of the machine with anti-friction bearing of the table with that of the same machine with hydrostatic bearing.
OBS: The above context was taken from a source written by a non-native speaker of English.
OBS: double-housing vertical boring machine: A ""vertical boring mill"" was originally a machine with one or two ram-type heads, while a ""vertical turret lathe"" was a machine with a vertical, turret-type head ... Modern machines frequently combine the two types of heads ... Consequently all machines of this type are now generally called vertical boring machines.