A complete hydraulic tool system consists of five parts, namely, power components, the implementation of components, control components, auxiliary components and hydraulic oil. The function of the power element of the hydraulic tool is to convert the mechanical energy of the prime mover into the pressure energy of the liquid. Refers to the oil pump in the hydraulic system that provides power for the entire hydraulic system. The structure of the hydraulic pump is generally gear pump, vane pump and plunger pump.
The function of actuators (such as hydraulic cylinders and hydraulic motors) is to convert the pressure energy of the liquid into mechanical energy to drive the load to reciprocate or rotate linearly.
The control elements of hydraulic tools (I. e. various hydraulic valves) control and regulate the pressure, flow and direction of the liquid in the hydraulic system. According to the different control functions, hydraulic valves can be divided into pressure control valves, flow control valves and directional control valves. Pressure control valves are divided into relief valves (safety valves), pressure relief valves, sequence valves, pressure relays, etc. The flow control valve includes a throttle valve, a regulating valve, a split flow collecting valve, and the like. Directional control valves include check valves, hydraulic control check valves, shuttle valves, reversing valves, etc. According to the different control methods, hydraulic valves can be divided into switch control valves, fixed value control valves and proportional control valves.
The auxiliary parts of hydraulic tools include oil tank, oil filter, oil pipe and pipe joint, sealing ring, pressure gauge, oil level and oil temperature gauge, etc. Hydraulic oil is the working medium to transfer energy in the hydraulic system, including mineral oil, emulsion, synthetic hydraulic oil and so on.
The auxiliary parts of hydraulic tools include hydraulic wrench, special electric pump for hydraulic wrench, hydraulic jack, hydraulic bolt tensioner, hydraulic flange separator, hydraulic nut crusher, hydraulic puller, etc. Hydraulic tools have the advantage of convenience. Creda hydraulic tools have been widely used in the global and China's steel, shipbuilding, electric power, petroleum, chemical, railway, metallurgy, bridge construction and other engineering maintenance and repair operations, but also serve a large number of building demolition, engineering construction, road construction, water conservancy and other construction occasions.
Advantages of hydraulic tools:
1. Generally, mineral oil is used as the working medium, and the relative moving surface can be lubricated by itself, and the service life is long.
2. Light weight, small size, small inertia and fast reaction speed.
3. Various components of hydraulic tool transmission can be arranged conveniently and flexibly according to needs.
4. Overload protection can be realized automatically.
5. Convenient operation and control, can achieve a wide range of stepless speed regulation (speed range up to 2000:1).
6. It is easy to achieve linear motion.
7. It is easy to realize the automation of the machine. When electro-hydraulic combined control is adopted, not only a high degree of automatic control process can be realized, but also remote control can be realized.
Disadvantages of hydraulic tools
1. Easy to leak: The oil pressure of the hydraulic tool system is high, and the hydraulic oil is easy to leak through the seal or gap, causing the consumption of hydraulic medium and environmental pollution.
Low transmission efficiency: In the energy transmission process of hydraulic tool transmission, there are often many energy losses (pressure loss and flow loss, etc.), which makes the transmission efficiency low.
3. The transmission ratio is not allowed: Due to the compressibility of the hydraulic tool transmission medium, leakage and elastic deformation of the pipeline, the hydraulic system cannot strictly guarantee the constant ratio transmission.
4. Sensitive to temperature: The viscosity of oil changes with temperature, and changes in viscosity cause changes in flow, leakage and resistance, which can easily lead to unstable movement of the working mechanism.
5. High manufacturing cost: In order to reduce leakage, high manufacturing accuracy of hydraulic components is required, thereby increasing manufacturing costs.