How to Properly Maintain a Hydraulic Bending Machine？

1. Daily Maintenance (Before, During, and After Each Shift)

This is the most basic and important step, to be completed by the operator.
(1). Before Work:
Check Hydraulic Oil Level: Check the oil level indicator in the hydraulic oil tank to ensure the oil level is between the specified upper and lower limits. Low oil levels can cause the pump to cavitate, damaging the hydraulic pump.

Check Lubrication System: Manually or automatically add lubricating oil (grease) to friction points such as the slider and guide rail, cylinder piston rod, lead screw, and bearings, according to equipment requirements. Ensure the lubrication path is unobstructed.

Check Cleanliness:
Hydraulic Oil: Observe the oil color through the tank window to see if it is normal (usually pale yellow or transparent). If the color is black or cloudy, the oil is contaminated.

Filter: Check the return oil filter indicator. If it shows blockage, replace or clean the filter element promptly.

Check Fasteners: Check the bolts on key parts such as the mold, clamping blocks, and stoppers for looseness.

No-load test run: Start the machine and run it for several cycles without load. Listen for any abnormal noises and observe whether each action (ascending, descending, pressure adjustment) is smooth and normal.

(2) During operation:
Pay attention to abnormal phenomena: Closely monitor the equipment's operating status. If abnormal noise, vibration, leakage, odor, or unstable pressure occurs, stop the machine immediately for inspection.

Keep the equipment clean: Prevent dust, chips, coolant, and other foreign objects from entering the hydraulic system or electrical box. After work, clean metal shavings and oil stains from the worktable and molds.

Use molds correctly: Use appropriate molds and avoid overloading. It is strictly forbidden to strike or adjust workpieces on the equipment.

(3) After work:
Cleaning and tidying: Thoroughly clean the machine tool and work area.
Slider descent: Lower the slider to its lowest point so that it contacts the lower mold to protect the cylinder and guide rail.
Power and air cut-off: Turn off the main power and air supply.

2. Regular Maintenance (Weekly, Monthly, Yearly Plans)

This work needs to be performed by professional maintenance personnel or under their guidance.
(1) Weekly/Monthly Maintenance
Hydraulic System:
Leak Check: Carefully check all hydraulic lines, joints, and cylinder seals for oil leaks and address them promptly.
Air Purging: Air in the hydraulic system can cause unstable operation and noise. Open the air vent valves on the cylinders or lines to vent the air.

Electrical System:
Cleaning and Tightening: After power is off, clean the dust inside the electrical cabinet and check for loose terminals.
Check Switches and Sensors: Check the position of limit switches, proximity switches, etc., for accuracy and reliable operation.

Mechanical Parts:
Guide Rails and Sliders: Check the guide rail surfaces for scratches or wear, remove old sludge, and reapply new grease.
Synchronization Mechanism: Check the torsion shaft (or hydraulic servo) synchronization mechanism for smooth operation and no jamming.

(2) Semi-annual/Annual Maintenance (Major Maintenance)
Hydraulic Oil Change: This is the most important periodic maintenance item. It is generally recommended to change the hydraulic oil annually, but this should be shortened to semi-annually under harsh operating conditions. When changing the oil, the suction filter and return filter element in the oil tank must be cleaned or replaced simultaneously.

Note: Different brands and models of hydraulic oil cannot be mixed.

(3) Comprehensive Inspection of Hydraulic Components:
Hydraulic Pump: Check if its output pressure and flow rate reach the rated values, and whether there is any abnormal noise or temperature rise.
Hydraulic Valve Assembly: Check whether the solenoid valves, relief valves, proportional valves, etc., are sensitive in operation; clean or calibrate if necessary.
Hydraulic Cylinder: Check the piston rod surface for scoring or corrosion. Minor damage can be repaired with an oilstone.

Accuracy Check and Calibration: Use a dial indicator to check the parallelism of the slider and the flatness of the lower worktable.
Check the repeatability of the back gauge (R-axis).
Make necessary mechanical adjustments or CNC system parameter compensation based on the inspection results.

Safety Device Testing:
Emergency Stop Buttons: Test the sensitivity and effectiveness of all emergency stop buttons.
Safety Light Barriers/Guardrails: Test their functionality to ensure the machine stops immediately when the light barrier is blocked.
Two-Hand Operation Buttons: Check the reliability of their interlocking function.

3. Key Maintenance Points for Hydraulic Bending Machine Components

Hydraulic Oil: It is the "blood" of the hydraulic system.
Keep it clean: Contamination is the primary cause of hydraulic system failure. Oil must be added through a filter; any contaminants must not enter the oil tank.
Control oil temperature: The ideal oil temperature should be between 35℃ and 55℃. Excessive oil temperature will accelerate oil oxidation and deterioration, damaging seals. If the oil temperature is too high, check if the cooler is clogged or inefficient.

Die: After use, apply rust-preventive oil and store them neatly and separately.
Regularly inspect the cutting edges and cavities of the dies. If there are any dents or wear, repair them promptly.
Seals: Regularly check the sealing condition of the cylinder and valve block. If leakage is found, replace the seals immediately. When replacing, ensure the installation direction and grooves are clean to avoid damaging the new seals.