When the handwheel is rotated toward the open position the upper stem is moved away from the diaphragms allowing the spring to push the lower stem away from the seat.

当手轮象开启位置旋转时，上阀杆离开横膈膜，弹簧推动下阀杆离开阀座。

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When the handwheel is rotated toward the open position the upper stem is moved away from the diaphragms allowing the spring to push the lower stem away from the seat.

当手轮象开启位置旋转时，上阀杆离开横膈膜，弹簧推动下阀杆离开阀座。

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