Профессиональный английский язык/ преподаватель Щаева А.М.
Выполнить все задания в практических работах 1-15 ПРАКТИЧЕСКАЯ РАБОТА № 1 Задание 1 Прочитайте и устно переведите текст. Письменно переведите 1, 2 и 3 абзацы . REDUCTION GEARS AND COUPLINGS On practically all turbine ships, main turbines drive the propellers through mechanical reduction gears or by electrical transmission. When reduction gears are used, flexible couplings are employed between the turbines and the gear sets. Gears or toothed wheels are used to transmit rotary motion and torque from one shaft to another which may have a different speed or different direction of rotation or both. Most present-day merchant marine turbines operate at speeds ranging between 3,000 and 10,000 r.p.m. and are connected to large, slow-turning propellers which operate at anywhere from 80 to 100 r.p.m. Consequently, a double reduction main propulsion gear unit is required to provide the necessary speed reduction. Conventional practice employs two co