Abstract: There is provided a ventilation apparatus with counter-rotating impellers driven by long shaft, wherein an electric motor and a gearbox are placed outside the air duct by using a long shaft with an internally disposed slim shaft extending therefrom, and are connected with the first stage impeller and second stage impeller inside the air duct by using the long shaft and slim shaft extending therefrom. In this ventilation apparatus with counter-rotating impellers, the components of the ventilation apparatus are placed inside and outside the air duct respectively by using the transmission shaft, which is convenient for maintenance and operation. By remotely arranging the impellers at an axial distance, the hub of the impellers will no longer be affected by an internally disposed electric motor, so as to reduce the ventilation resistance to ventilation. The impellers can be switched between the single impeller rotation and the counter rotation of two impellers.

Abstract: Provided is an electromechanical-linkage hydraulic control gate valve actuator. The actuator includes a hand-operated speed-increasing gearbox assembly and a bidirectional throttle valve. In the present invention, a motor is driven to rotate through the hand-operated speed-increasing gearbox and thus a hydraulic system is driven to finally open and close a gate valve. An opening and closing speeds of the gate valve can be regulated and controlled through the bidirectional throttle valve. The present invention drives the motor through the hand-operated speed-increasing gearbox under emergency conditions such as repair and power failure, thereby controlling to open and close the gate valve. Meanwhile, a hydraulic system respectively regulates the speeds of two states of opening and closing through a bidirectional throttling technique, so as to effectively eliminate a water hammer phenomenon. The present invention has simple structure, light weight and modular installation, and enhances safety and reliability.

Abstract: Provided is an electromechanical-linkage hydraulic control gate valve actuator. The actuator includes a hand-operated speed-increasing gearbox assembly and a bidirectional throttle valve. In the present invention, a motor is driven to rotate through the hand-operated speed-increasing gearbox and thus a hydraulic system is driven to finally open and close a gate valve. An opening and closing speeds of the gate valve can be regulated and controlled through the bidirectional throttle valve. The present invention drives the motor through the hand-operated speed-increasing gearbox under emergency conditions such as repair and power failure, thereby controlling to open and close the gate valve. Meanwhile, a hydraulic system respectively regulates the speeds of two states of opening and closing through a bidirectional throttling technique, so as to effectively eliminate a water hammer phenomenon. The present invention has simple structure, light weight and modular installation, and enhances safety and reliability.

Abstract: There is provided a ventilation apparatus with counter-rotating impellers driven by long shaft, wherein an electric motor and a gearbox are placed outside the air duct by using a long shaft with an internally disposed slim shaft extending therefrom, and are connected with the first stage impeller and second stage impeller inside the air duct by using the long shaft and slim shaft extending therefrom. In this ventilation apparatus with counter-rotating impellers, the components of the ventilation apparatus are placed inside and outside the air duct respectively by using the transmission shaft, which is convenient for maintenance and operation. By remotely arranging the impellers at an axial distance, the hub of the impellers will no longer be affected by an internally disposed electric motor, so as to reduce the ventilation resistance to ventilation. The impellers can be switched between the single impeller rotation and the counter rotation of two impellers.