What Is The Working Principle Of The Oil Delivery Arm?

What is the working principle of the oil delivery arm? Marine fluid loading and unloading arm, also known as oil delivery arm, is a specialized equipment that connects pipelines with rotating joints and is supported by a supporting structure, bridging between the dock and the tanker for fluid material loading and unloading, including control systems and other accessories prepared according to user requirements.
1. Balancing principle of oil delivery arm
The empty state of the oil delivery arm should maintain balance between the inner and outer arms, and the inner and outer arms should have a tendency to return to the non working state. The balance weight structure can meet this requirement. The oil delivery arm has two balancing weights: the main (inner arm counterweight) and the auxiliary (outer arm counterweight), which can achieve static balance.
The principle of main counterweight balance is that the rotating joint in the middle of the inner arm is the rotating shaft, and the weight moment generated by the weight of the upper end of the inner arm, the upper rope wheel, and the outer arm is balanced with the gravity moment generated by the main counterweight, the lower rope wheel, and the auxiliary counterweight at the lower end of the inner arm. Adjusting the weight of the main counterweight at the lower end of the inner arm can ensure that the inner arm is balanced and has a tendency to return to its original position when it is not in operation.
The principle of auxiliary counterweight balance is achieved through the upper and lower rope wheel mechanisms. The weight of the outer arm drives the upper rope wheel to have a torque to resell in one direction, and the torque balance is opposite to the torque balance of the auxiliary counterweight driving the lower rope wheel to rotate in the opposite direction. Adjusting the angle between the auxiliary counterweight and the inner arm (retracting and releasing the rope wheel wire rope) or adjusting the position of the auxiliary counterweight on the beam (lifting the auxiliary counterweight) can ensure that the outer arm is balanced and has a tendency to return to its original position when it is not in operation.
2. Working principle of hydraulic system
Each hydraulic oil delivery arm has three sets of oil cylinder drive systems, among which the oil tank, oil pump, and overflow valve are shared.
Hydraulic oil is sucked into the oil pump through the oil filter on the oil tank, pressurized by the oil pump, and enters the three-position four-way directional valve through the throttle valve. Manipulating the directional valve can change the direction of oil in and out of the cylinder, thereby driving the piston rod inside the cylinder to perform reciprocating motion. If the inner arm drives the oil cylinder, it drives the inner arm of the oil delivery arm to swing back and forth; If the outer arm drives the oil cylinder, it drives the outer arm to swing up and down; If it is a horizontal rotary cylinder, it drives the inner and outer arms to perform horizontal rotary motion.
The overflow valve can adjust the working pressure of the hydraulic system, and the throttle valve can adjust the speed of the cylinder piston rod movement.
Due to the limitation of the movement stroke of the oil cylinder piston, the hydraulic oil delivery arm is equipped with a limit alarm system to prevent damage to the oil cylinder beyond the allowable working range.