液压螺栓由三部分组成：锥形螺栓、锥套、螺母。其工作原理是锥形螺栓与锥套间的圆锥面相配合，通过专用工具将锥形螺栓拉入锥套，进而使锥套定量膨胀，完成液压螺栓与螺孔间可控制的径向过盈配合。
与传统联轴器螺栓相比，液压螺栓使联轴器扭矩传递由摩擦力扭矩转变为剪切力扭矩，而且径向膨胀和轴向加载的设置，可以精确到预定水平，过盈配合和轴向预紧力消除了联轴器的滑移，扭矩传递稳定高效。
液压螺栓在较高扭矩或高价值的设备中得到充分利用。在这些设备中，对联轴器联接性能的苛刻要求、最优化的结构设计以及扭矩传递的安全性、稳定性必须得以保证。
液压螺栓技术是发电行业联轴器联接极为成熟的解决方案，得到业界的广泛支持。从常规的蒸汽到高效燃气轮涡轮机所有类型设备，到水力和风力涡轮机，还有大型电动机驱动、船舶推进轴系和重型旋转机械。
液压螺栓的结构是对传统联轴器螺栓的直接改造或替代，不仅提高了联轴器的性能，保护联轴器本体，更加易于安装和拆卸，大大节约时间成本，为大型设备及其企业带来客观的经济效益。
The hydraulic bolt consists of three parts: conical bolt, conical sleeve and nut. Its working principle is that the conical bolt is matched with the conical surface between the conical sleeve, the conical bolt is pulled into the conical sleeve through special tools, and then the conical sleeve expands quantitatively to complete the controllable radial interference fit between the hydraulic bolt and the screw hole.
Compared with the traditional coupling bolt, the hydraulic bolt changes the coupling torque transmission from friction torque to shear force torque, and the setting of radial expansion and axial loading can be accurate to the predetermined level. The interference fit and axial preload eliminate the slip of the coupling, and the torque transmission is stable and efficient.
Hydraulic bolts are fully utilized in high torque or high-value equipment. In these equipment, the strict requirements for the coupling performance, the optimal structural design and the safety and stability of torque transmission must be guaranteed.
Hydraulic bolt technology is a very mature solution for coupling connection in power generation industry, which has been widely supported by the industry. All types of equipment, from conventional steam to high-efficiency gas turbine, to hydraulic and wind turbines, as well as large motor drives, ship propulsion shafting and heavy rotating machinery.
The structure of hydraulic bolt is a direct transformation or replacement of the traditional coupling bolt, which not only improves the performance of the coupling, protects the coupling body, is easier to install and disassemble, greatly saves time and cost, and brings objective economic benefits to large equipment and enterprises.
