reason The damage to the bucket hydraulic cylinder is mainly due to the fracture of the steel ring on the piston due to factors such as fatigue. The piston is in direct contact with the metal of the hydraulic cylinder barrel. In the frequent expansion and contraction of the piston rod of the hydraulic cylinder, the fractured stubble constantly scrapes the inner wall of the hydraulic cylinder, which will strain the cylinder wall and cause internal leakage. The speed of the hydraulic cylinder is reduced, and finally the operation valve cannot control the action of the hydraulic cylinder.

The damage of the working device under typical working cycle conditions: For the boom, the earliest damage occurs at the boom ear plate. After analysis, this part is the direct bearer of the force of the stick cylinder, with local stress concentration and the thickness of the ear plate. It is thinner, so it is damaged at the earliest; for the stick, the earliest damage occurs around the pin that is hinged with the boom and inside the pin. After analysis, this part is the connection position between the edge of the stick box and the pin, which is prone to stress concentration. , and is also the position where the stick is subjected to alternating loads, so it is damaged at the earliest.

What is an actuator? The basic hydraulic system includes oil tank, pump, control valve, oil cylinder, connecting line and relief valve. The cylinder is the actuator. Actuators are hydraulic system components that output power. Actuators convert hydraulic energy into mechanical energy. There are two types of actuators: linear and rotary. Hydraulic cylinders are linear actuators. It outputs force and linear motion. The hydraulic motor is the rotary actuator, which outputs torque and rotary motion.

At present, R-rings have basically become standard on Rexroth industrial valves, and have achieved good results in the food, pharmaceutical processing and plastic machinery industries that have strict requirements on leakage. So, why choose R-rings instead of the commonly used O-rings? The R-ring has a large contact area, and the heat generated during the movement is difficult to dissipate, so it is generally only used for static sealing;

(1) In terms of production capacity and market, the output of domestic hydraulic presses has a great growth rate every year. In 2004, the sales of domestic hydraulic presses were about 1 billion yuan, and in 2005 it reached 1.3 billion! By 2012, it has exceeded the 10 billion mark! In 2019, tens of millions of tons of hydraulic presses were built, which are rare in the world. The domestic sales of domestic hydraulic presses exceed 90%, and the output value of export products accounts for a very small proportion of the total output value, less than 5%. Only a few companies have products that are eligible for export, and most of them are exported to third world countries. Most of the hydraulic presses imported in China are some hydraulic presses, most of which are imported products, and there are fewer products in Europe and America.

Compared with foreign products, my country's products still have the following shortcomings in terms of quality: ①In terms of reliability, the failure rate is still relatively large, mainly in the hydraulic system, mostly due to the low reliability of hydraulic and electrical components; ② Oil leakage is common in domestic hydraulic presses;