A metal sheet bending machine called brake press or press brake machine is the core equipment of the metal processing industry, its performance and life depend largely on the daily maintenance work, regular maintenance can not only extend the service life of the bending machine but also troubleshooting, reduce the rate of damage to the workpiece, improve the accuracy of the machine, as well as reduce the potential danger to the operator.
The maintenance of the brake press machine is divided into four key areas, namely, hydraulic circuits, mechanical systems, electrical systems, and tooling, the following steps will significantly improve the bending performance and reduce the wear of mechanical components.
1. Review the surrounding area and make a thorough inspection.
Before proceeding with a formal bending operation, carefully inspect the work area and the overall condition of the machine to prevent any possible minor problems in advance.
Ensure that the brake press machine is in a clean condition, check that the table and mold area are free of abrasive chips and residue, and make sure that there are no cracks in the upper and lower molds. If there are dents and cracks in the molds, they have been subjected to too much force and need to be repaired or replaced.
Check the accuracy of the back gauge and the position of the stop finger. In addition, all buttons, switches, indicators, and foot controls should be tested for sensitivity and proper functioning, as well as some important parts that require special maintenance. If there are additional guards, make sure that they are set up and function in accordance with the specifications.
2. Hydraulic system maintenance
Hydraulic oil is the lifeblood of the bending system, that is, the “blood” of the bending machine, we should pay attention to keeping the hydraulic oil and the hydraulic circuit clean, the hydraulic circuit includes the oil tank, valve group, pipeline, motor, pump, and other components. For the oil tank level, daily should be like checking the oil level of the car, a simple visual inspection on a regular basis, otherwise it will affect the operation of the hydraulic pump, resulting in insufficient power to drive the plunger, to ensure that the oil tank is well sealed and ventilated.
In addition, it is not possible to make a complete seal of the oil tank, make sure that the oil cap seals and air breather are intact. Prevent a vacuum from forming in the tank by mounting an air breather on the tank cover to allow air to flow through the tank as it pumps oil to the cylinders, and if there is dirt in the oil, it will make the pumps and valves operate abnormally. Most problems in hydraulic circuits are related to oil contamination. Dirt in the system can cause valves to seize in the open or closed position and damage the pump system through gradual loss of pressure.
The quality and viscosity of the oil should also be checked every 2,000 hours of operation, and it is a good idea to provide an oil sample to your oil supplier, who will be able to provide a complete profile detailing the condition of the oil and recommending whether to change or filter the oil.
3. Mechanical components
The mechanical parts of the brake press machine, piston bolts, sprockets, and guides, should be inspected at least twice a year. The mechanical parts must be checked regularly to ensure that all parts are stable and all bolts, nuts, and screws are tightened regularly to ensure that the connection between the piston and the plunger are in good condition. Recalibrate the backgauge stop fingers and check for cracks in the connecting parts of the base.（It’s even more important to make sure of these parts when you buy a used press brake machine.）
In addition, lubricating the components of the bending machine can also effectively extend the service life of the machine, when these components slide, friction, can effectively reduce the friction damage to the components, need to be regularly lubricated and cleaned parts include ball screws, guide rails, rear stops and their gears, etc., these parts should be lubricated at least once a week, but also be careful not to over-lubricate the machine.
But also be careful not to over-lubricate, otherwise, it will lead to insufficient friction or parts contamination, before applying lubricant, you should ensure that it is the manufacturer’s recommended lubrication product.
4. Electrical equipment
Maintenance of the electrical equipment is essential to prolong the life of the bending machine and should be checked at least once a year, including all electrical connections and switches.
Before carrying out the inspection, make sure that the main power switch is turned off that the system is locked out, and that the necessary safety measures are taken in order to cope with certain inspections that must be carried out with the power on.
Regarding electrical components requiring maintenance: Check the connection status of the terminal box and terminal block on the relay. Check that all wires are not loose and that there is no physical damage (damaged insulation, burnt parts)
Check for fan operation, all cables and switches for damage or malfunction, and operation of all machine functions and safety features. Keeping the internal and cooling fans running, the air conditioning system, and the heat exchanger filters clean Keeping the internal panel temperatures within the manufacturer’s specified limits is effective in keeping the electrical components free from contamination.
5. Inspection of punches and press brake dies
Not all tooling can be maintained in the same way and pressure brake tools should only be ground or refurbished by the tool manufacturer.
After use, punches and dies require regular maintenance to keep them clean and free of scale. The dies should be visually inspected before each use as a means of avoiding rust and corrosion, and any breakage or damage should be returned to the toolmaker for evaluation, repair, or replacement. The use of broken dies poses a great risk to the machine and the operator.
Conclusion: Regular maintenance of the bending machine can effectively extend its service life, for its hydraulic circuit, mechanical system, electrical system, and tools should be done on a regular basis at regular intervals, in addition to focusing on the bending machine itself clean, clean work area is also important, clean work area can effectively reduce the probability of problems with the bending machine.
