Why does the bending machine cylinder rebound upward?
4 Answers
The upward rebound of the bending machine cylinder is caused by the movement of the cylinder piston. Bending Machine: A bending machine is a device capable of bending thin plates. Its structure mainly includes a bracket, workbench, and clamping plate. The workbench is placed on the bracket and consists of a base and a pressure plate. The base is connected to the clamping plate via a hinge. The base is composed of a housing, coil, and cover plate, with the coil placed in the recess of the housing and the top of the recess covered by the cover plate. During operation, the coil is energized by wires, generating a magnetic force on the pressure plate, thereby clamping the thin plate between the pressure plate and the base. Due to the use of electromagnetic clamping, the pressure plate can be designed to meet various workpiece requirements, and it can process workpieces with side walls, making the operation very convenient. Features of the Bending Machine: It adopts an all-steel welded structure, providing sufficient strength and rigidity; hydraulic upper transmission, with cylinders at both ends of the machine installed on the slider, directly driving the sliding work; the slider synchronization mechanism uses a torsion shaft for forced synchronization; it employs a mechanical stop structure, ensuring stability and reliability; the slider stroke can be quickly adjusted mechanically and finely tuned manually, with a counter display; a wedge-type deflection compensation mechanism ensures high bending accuracy.
I've been in mechanical maintenance for over 30 years, and the issue of the bending machine's oil cylinder rebounding upward is quite common. The problem usually lies in the instability of the hydraulic system, such as a clogged hydraulic valve or oil leakage, causing pressure fluctuations that make the cylinder rise and then bounce back down. It feels similar to how a car's body shakes up and down when the suspension system has an air leak—the principle is analogous: poor oil flow leads to delayed or failed control signals. During inspection, I first check if the hydraulic oil level is sufficient and whether there are any contaminants, as dirty oil can easily jam the valve. Then, I test if the pressure gauge readings are normal; if they're too low, it might indicate a leak or an aging pump. Regular maintenance, such as changing the oil and filters and keeping the oil lines clear, can prevent 90% of these issues. If all else fails, disassemble the cylinder to inspect the seals—replace them if they're worn out, and don't wait until the cylinder deforms.
I usually operate a bending machine, and the cylinder rebound is really annoying, often due to inadequate maintenance. When hydraulic oil isn't changed for a long time and deteriorates, impurities accumulate and clog the pipes, causing insufficient air pressure during the cylinder's upward stroke and resulting in rebound. It's just like when sludge in a car engine clogs the pipes, making movement less smooth. It's recommended to check the oil color before each startup and replace it immediately if it appears cloudy. Don't overlook the seals either—adding some lubricant can extend their lifespan. If a malfunction occurs, don't force it; try turning off the power and cleaning the oil circuit, such as disassembling the cylinder inlet to remove debris. Get into the habit of recording usage monthly to save a lot on repair costs.
The bending machine in our workshop keeps acting up like this, with the oil cylinder bouncing violently when it rises. I suspect it's a control system issue. Faulty sensor feedback or a malfunctioning limit switch can cause the oil cylinder to lose position control, retracting as soon as you release it. It's the same principle as unstable idle speed caused by ECU programming errors in cars. Try adjusting the speed and setting position points slower during operation—sometimes that works. If not, have an electrician check for loose wiring to minimize downtime with quick repairs.
