Most press brake faults are hydraulic, electrical or mechanical, and the archived maintenance manual gives a short, practical list: check the cause before acting, stop the machine immediately when anything abnormal appears, and never exceed the machine’s nominal pressure or the 1000 kN per meter die-protection limit. This guide explains the common press brake faults, their causes and the fixes from Maofeng’s archived supplier maintenance material (2026-10-09), plus the maintenance rules that prevent most of them.
Common press brake faults and fixes
The archived fault table lists five typical faults with their causes and removal methods:
| Fault symptom | Cause | Fix (archived) |
|---|---|---|
| Oil pump delivers no oil; hydraulics do not move | Oil pump rotation direction wrong | Ajustar a fase do motor principal |
| Components, pipe joints or cylinders leak oil | Seal damaged or aged | Replace the seal |
| Piping and machine vibrate; hydraulic pressure cannot build up | Oil level low in the tank, filter screen blocked, suction line starving | Fill oil to the tank gauge center, clean the filter screen, bleed air |
| Slide creeps (chatters) or travels too slowly on the way down | Hydraulic pilot check valve restricted or opening too small; oil too cold; viscosity too high | Check valve 14 and the pilot oil circuit; idle the machine to warm up or change to lower-viscosity oil |
| Loud impact noise when the slide returns | Time relay faulty or delay inaccurate | Verifique e ajuste o atraso para cerca de 1 segundo |
These are the archived diagnoses and fixes; actual repair should follow the machine manual and be done by trained personnel. The pressure circuit is explained further in the Guia do sistema hidráulico da prensa-dobra.
Preventing press brake faults
The archived maintenance rules that prevent most faults:
- Bending pressure must never exceed the machine’s nominal pressure.
- To protect die life, bending force per meter must not exceed 1000 kN.
- Keep the hydraulic oil clean and the oil circuit clear; maintain good lubrication at every lubrication point.
- Avoid offset loading – generally solved by bending both sides simultaneously.
- Keep the specified random accessories and wearing parts in stock.
- Stop and inspect immediately when any abnormal phenomenon appears.
For the full checklist, see the guia de manutenção da prensa-dobra.
Safety when repairing a press brake
The archived manual states that a press brake is a forging/forming product machine; operators and maintenance staff must be trained, know the safety rules, and protect people and equipment. New Maofeng machines include infrared safety guarding as standard (archived configuration advantage). The archived fault-finding is inspection and adjustment work – pressure testing and electrical work should follow the machine’s own documentation.
When to call the supplier
Maofeng’s archived profile states 20 domestic service points and 9 overseas stations, with support covering machine repair, technical guidance and after-sales maintenance. The archived warranty is 12 months on the whole machine (wearing parts such as dies, seals and blades excluded; extended warranty negotiable). For warranty or repair service, contact Maofeng with the machine model, controller and the fault description.
Perguntas frequentes
Why does my press brake not build pressure?
Archived fix order: check the oil level (fill to the tank gauge center), clean the filter screen, bleed the suction line, and check the pump rotation direction – if the pump turns the wrong way, adjust the main motor phase.
Why does the slide creep on the way down?
Archived causes: pilot check valve restricted or opening too small, oil too cold, or viscosity too high. Check valve 14 and the pilot oil circuit, warm the machine up by idling, or use lower-viscosity oil.
Why is there an impact noise when the slide returns?
Archived cause: time relay faulty or delay inaccurate; check and adjust the delay to about 1 second.
How do I stop leaks?
Archived cause: seals damaged or aged; replace the seal. Keep the oil clean and the circuit clear as preventive care.
How often should a press brake be serviced?
The archived manual requires daily maintenance and lubrication per the machine manual, and immediate inspection when abnormal conditions appear; the detailed schedule is in the maintenance guide.
Por onde começar
For repair questions, use the Maofeng contact page with the model and fault description; for machine selection, review the Configurações das prensas dobradoras hidráulicas CNC or the CNC press brake guide.
