The oil cylinder of shield tunneling machine is the key executing component of modern tunnel construction core equipment - shield tunneling machine, known as the power source of "underground dragon" and "giant artificial pangolin". These oil cylinders work in extremely harsh environments, including severe erosion from gravel, mud, dust, high pressure, continuous operation, and extremely high eccentric loads. Their performance directly affects the quality and efficiency of shield machine operation. As an important component of the hydraulic system of the shield machine, the oil cylinder is responsible for converting hydraulic energy into mechanical energy, providing the power and precise control required for various functions such as propulsion, steering, and stability of the shield machine.

In tunnel construction, the oil cylinder of the shield machine undertakes multiple key missions: the propulsion oil cylinder provides the main power for the shield machine to advance forward; The articulated oil cylinder enables the equipment to flexibly turn and adjust its posture; The stabilizing oil cylinder ensures that the shape of the tunnel segments is maintained and the concrete lining is clamped. These oil cylinders need to have extremely high reliability because once a malfunction occurs, replacement and repair are very difficult, and maintenance costs are extremely high, which will seriously affect project progress and economic costs. Therefore, the design, manufacturing, and quality control of shield tunneling machine oil cylinders represent the highest level of technology in the hydraulic field.

With the continuous development of China's infrastructure construction and the in-depth promotion of the "the Belt and Road" initiative, the shield cylinder, as a key basic component, has become an important indicator of the level of a country's equipment manufacturing industry in terms of its technical level and product quality. Leading domestic enterprises such as XCMG Hydraulic, Hengli Hydraulic, and Chuanrun Co., Ltd. have broken the foreign technology monopoly through continuous technological innovation, enabling Chinese made Shield machine oil cylinders to not only meet domestic demand but also enter the international market, contributing to global urban construction.

Propulsion oil cylinder: This is the type of oil cylinder with the largest number, diameter, and stroke on shield tunneling machines. It has a high working pressure and can withstand extremely large radial eccentric loads, resulting in harsh working environments. The main function of the propulsion cylinder is to provide the main driving force for the forward excavation of the shield machine, and its performance directly determines the excavation efficiency and stability. According to information from Chuanrun Co., Ltd., its propulsion cylinders can be applied to shield machines over 3.7m, open TBMs, and double shield TMBs.

Articulated oil cylinder: Articulated oil cylinder is a key component that enables the shield machine to flexibly turn and adjust its posture. In the process of advancing the shield machine, when the curvature radius is very small, the articulated oil cylinder can achieve the function of turning the cutterhead or cooperating with tool change, as well as dragging the shield tail forward. The articulated oil cylinder produced by Chuanrun Co., Ltd. can be applied to shield machines over 2.6m, various open and double shield TMBs.

Lifting oil cylinder: The lifting oil cylinder is mainly used for the lifting and position adjustment of shield tunneling machines. Hengli Hydraulic's latest patent for "Shield Machine Lifting Cylinder" adopts an innovative design, including cylinder barrel, first piston rod, first guide sleeve, spacer assembly, piston, second piston rod, second guide sleeve, and cover, effectively solving the problem of crawling and shaking of the cylinder when carrying changing lateral loads.

Stable oil cylinder: This type of oil cylinder is mainly used for functions such as maintaining the shape of tunnel segments, clamping concrete lining, etc., to ensure the stability and construction quality of tunnel structures.