1. A semi-trailer is a trailer with an axle placed behind the center of gravity of the vehicle (when the vehicle is evenly loaded) and equipped with a coupling device that can transmit horizontal and vertical forces to the tractor. Semi-trailers are generally three-axle semi-trailers, which are divided into many types such as 11-meter warehouse semi-trailers, 13-meter warehouse semi-trailers, low-bed semi-trailers, etc. It is a heavy-duty transportation vehicle connected to the semi-trailer head through a towing pin.
2. The semi-trailer dump truck is side by side with the adjacent vehicle and confirms that it is about 1 meter away from the adjacent vehicle. After confirming that the rear is safe, reverse in a straight line. When the rear bumpers of the vehicles are side by side, stop.
3. Turn the steering wheel right and reverse to the target position. When the vehicle is stopped, turn the steering wheel to the right to the bottom; slightly relax the brake pedal and use the creeping function of the semi-trailer dump truck to reverse. When the left side of the vehicle body reaches the straight line extending from point A, it stops.
4. Turn the steering wheel left, straighten the tires and then reverse. When the vehicle is stopped, turn the steering wheel to straighten the tires; reverse slowly and straight, and stop when the left rear wheel reaches the white line outside the parking space.
5. Move the car to the right. Turn the steering wheel of the semi-trailer dump truck to the left and slowly reverse; before the vehicle is parallel to the shoulder, turn the direction to straighten the vehicle and park the vehicle parallel to the shoulder. Be careful not to collide with the vehicle behind. Semi-trailer dump trucks are large vehicles, so it is important to be careful when parking.
6. Take a manual jack to illustrate its working principle. The jack is the simplest oil cylinder. The hydraulic oil enters the oil cylinder through a one-way valve through a manual booster rod (hydraulic manual pump). At this time, the hydraulic oil entering the oil cylinder cannot be reversed due to the one-way valve, forcing the cylinder rod upward, and then continue to make the hydraulic oil enter the hydraulic cylinder during work, so that it continues to rise. When it is time to lower, open the hydraulic valve to return the hydraulic oil to the tank. This is the simplest working principle, and the others are improved on this basis.
