Hydraulic Tool Holder

Hydraulic toolholders are a widely used toolholder. The clamping method of this shank is different from the traditional shank system. Only one pressurized bolt is needed for tightening. When the bolt is tightened, the sealing block of the piston will be pushed to generate a hydraulic oil pressure in the shank, and the pressure will be evenly distributed. It is transmitted from the circumferential direction to the steel expansion sleeve, and the expansion wall then clamps the tool.
The TENDO Slim 4ax, a high-rigidity and slender hydraulic tool holder, adopts this tool clamping system, which can control the radial runout error accuracy and repeatability of the system to less than 3μm. Due to the high-pressure oil pressure in the tool holder, when the tool is clamped, the built-in oil cavity structure and the existence of high-pressure oil greatly increase the structural resistance, which can effectively prevent the vibration of the tool and the machine tool spindle. The practical application shows that the use of this clamping system can not only improve the machining accuracy and quality, but also double the service life of the tool in the cutting process. In addition, these holders are not only maintenance-free and dirt-resistant, but also easy to use and securely clamp the tool. Because, when tightening the tool, the clamping pressure can direct any oil or impurities on the tool shank into the (machined) small grooves in the expansion sleeve, which cleans the clamping surface area and allows it to Keep it dry, eliminate slippage, and ensure that the torque of the spindle can be well transferred to the tool. The basic working principle of the hydraulic tool holder: If we use the concentric cylinders of two air-expanding shafts, seal the two ends to form a cylindrical cavity, fill one of the cylinders with hydraulic oil, and also have a good effect on the oil. Apply a certain pressure, and this pressure will be transmitted to every part of the oil chamber with an equal value. If the outer walls of these two concentric cylinders are made thin, they will expand outward after being pressed. will expand inward. According to this deformed thin wall, the expansion clamping of the inner hole and the expansion clamping of the outer diameter can be realized. Since the thin wall at this time is actually subjected to oil pressure evenly everywhere, after the inner hole and outer diameter of the part are tightened, its clamping accuracy will be very high, and the static pressure expansion mandrel and Hydraulic tool holders are developed based on this principle and successfully applied in the machinery manufacturing industry. Advantages of hydraulic expansion clamping:
1. Extremely high precision: end face runout accuracy (below 3μm)
2. In the entire clamping range, the expansion sleeve can stably maintain a cylindrical expansion, with large clamping force and good rigidity, and can transmit higher clamping torque;
3. Outstanding wear resistance; good adaptability to working conditions, easy operation; no need for expensive and complicated peripheral equipment; reduced equipment costs;
4. High processing efficiency, better flexibility of change.