How does not affect the hydraulic cylinder piston
In order to prevent the piston from hitting the cylinder head at both ends of the stroke, causing noise, affecting the accuracy of the work piece and even damaging the machine parts, buffer devices are often installed at both ends of the hydraulic cylinder in the hydraulic pump station system. Its function is to use the throttling principle of oil to realize the braking of moving parts. Commonly used buffer devices have three types: annular gap type, adjustable orifice type, and orifice variable type.
1. Annular gap type: When the buffer plunger enters the inner hole of the cylinder head matched with it, the hydraulic oil must pass through the gap to be discharged, which reduces the piston speed. Since the fit gap is constant, the cushioning effect is not adjustable, and as the piston speed decreases, the cushioning effect gradually weakens.
2. Adjustable orifice: When the buffer plunger enters the inner hole on the cylinder head, the hydraulic oil must pass through the throttle valve to be discharged. Since the throttle valve is adjustable, the cushioning effect is also adjustable, but this adjustment is the adjustment before the cushioning is performed, and the cushioning effect is still constant during the cushioning.
3. Variable orifice type: A triangular groove is opened in the axial direction of the piston, and its flow cross-section is getting smaller and smaller, and the buffering effect increases as the speed decreases. The buffering effect is uniform, the buffering pressure is low, and the braking position accuracy is high, which solves the problem of weak buffering in the final stage of the stroke.
Buffer device: gap buffer, throttling buffer, axial triangular groove buffer.
Regarding the exhaust of the hydraulic cylinder in the hydraulic pump station system. For hydraulic cylinders that have not been used for a long time or newly purchased hydraulic cylinders, air often accumulates in the highest part of the cylinder. The presence of air will cause the hydraulic pump station system to move unevenly, causing vibration or crawling. For this reason, an exhaust device should be provided on the hydraulic cylinder.
Exhaust devices usually have two forms: one is to open an exhaust hole at the highest part of the hydraulic cylinder, and use a long pipe to lead to a distant exhaust valve to exhaust; the other is to install directly on the highest part of the cylinder head Exhaust valve, for the hydraulic cylinder of the double-acting hydraulic pump station system, 2 exhaust valves should be provided.