The press brake ram cannot be quickly down

Causes:

  • The ram rail tuning too tight;
  • Backgauge axis is not in place;
  • The ram is not at the top dead center position;
  • Footswitch signals did not enter the module;
  • The malfunction of the proportional servo valve;

Solutions:

  • Check whether the ram rail is appropriate;
  • Check whether there is a cursor of the X-axis actual position on the controller,or to check whether the backgauge programming value and the actual value is consistent in the manual interface;
  • The Y-axis state should be “1” on the controller, ifitis “6”, check the actual coordinates of the Y axis, the value should be less than the difference between the Y-axis and return;
  • According to electrical schematics, check whether the input signals of the foot switch are normal;
  • Check whether the proportional servo valve feedback is normal;

The press brake ram cannot bend or bend speed is very slow

Causes:

  • The ram is not at the speed conversion point;
  • The set of the parameters of Y-axis bending is not good;
  • The pressure is not enough, such as programming, machine tool parameter settings, hydraulic;

Solutions:

  • Check whether the Y-axis state from ”2” to “3″ , Y-axis actual value should be greater than the speed conversion point value, if not need to adjust the parameters of the fast forward part;
  • Re-adjust part of the parameters the Y-axis bending;
  • Check whether the programming operation is not right, or parameter settings are wrong, or hydraulic problems; can use pressure gauge, multimeter to detect the main pressure and proportional pressure valve signal, and then check whether the proportional pressure valve, the main valve is stuck and then check the filter and oil, and finally check the pump and its coupling;

The ram cannot return during the bending process

Causes:

  • Cannot return without load, maybe the parameter’ S problem or hydraulic failure;
  • Can not return during bending, the workpiece angle does not meet the set value;
  • Can not return during bending, the workpiece angle has exceeded the set value;

Solutions:

  • Debugging the parameters of Y-axis, bending parameters should be based on actual debugging, part of the gain is too small, the ram cannot bend or not
    bend well, too much ram will shake, the parameters should be adjusted during the action the ram do not shake or a lttle bit more of the gain. Or the bias settings of the left and right valve are not good in diagnostic procedures. If too small Y-axis cannot be in place, if too large Y-axis cannot unload; If it is the hydraulic failure, need to check the main pressure, check whether the PV valve S5 has been in the power position;
  • Probably the gain set of Y-axis parameter is too small, can increase properly, or pressure is not enough, analyze the reason why the pressure is not enough.
    It is because of the program or signal, hydraulics; programming reasons include mold selection, plate thickness, materials, workpiece length, bending
    method, etc.; hydraulic reasons include: hydraulic pump leakage, the proportional pressure valve is contaminated or damaged, the filter is blocked,
    whether the oil has been polluted; Mainly the programming and operating reasons, check the program and the workpiece;

The ram moving is not good

Causes:

  • The tightness of the ram rail is not appropriate;
  • Ram lock nut loose;
  • Machine parameters need to be adjusted;
  • The gain, zero points on the amplifier of proportional servo valve need toadjust;
  • The back pressure valve pressure is not correct or the two sides are the imbalance. Back pressure setting is too small, the ram will slowly decline, and will shake during working process; two sides back pressure is imbalance, the ram will twist during running;

Solutions:

  • Re-adjust the guide clearance;
  • Re-locking, if the lock nut and screw are too loose, need to be replaced;
  • If there is a reference curve, should be adjusted according to the reference curve;
  • Only BOSCH, REXROTH valve can be adjustable, but need to be cautious;
  • Use pressure gauges to adjust the pressure of the back pressure valve, and make the two sides consistent;

The ram is waiting too long at the speed transition point

Causes:

  • The tank suction port leak;
  • Flling valve failure, such as the poor installation leads to the stuck of the valve core, or spring tension is not enough;
  • The set of Y-axis parameters is not good;

Solutions:

  • Check the sealing of the rubber sheet, re-install the cover here;
  • Check the flling valve installation, check the running of the valve core, check the spring tension;
  • Adjust the Y axis parameters;

A too large gap between ram and guide rail, make an abnormal sound

Causes:

  • This type of malfunction is due to the long use of rails, increased gap caused by wear.

Solutions:

  • It is necessary to check the degree of wear of the guide plate, to determine whether to replace the rail plate depending on the degree of wear, re- adjust the gap to meet the requirements.

Cylinder and ram connection loosening,causing bending angle not accurate or the machine cannot find the reference point.

Solutions:

  • This type of fault requires re-checking the tightened ram and the cylinder connection nut.

Ram speed turns to slow from fast, pause too long.

Solutions:

  • Check whether the tank oil surface is too low, the filling mouth was not flooded. When fast forward the cylinder chamber filled with liquid and air which leads to the insufficient filling. For the above reasons, the tank oil can be added to the filling tank 5mm above the filling mouth until it been completely flooded.
  • Check whether fast forward speed is too fast, causing insufficient filling. For the reasons described above, you can reduce the fast forward speed by modifying the system parameters.
  • Check whether the filling valve is completely open if it is because of oil pollution so that the valve spool activity is not flexible and stuck issue lead to insufficient oil filling. Need to clean the filling valve and re-install it, make the spool flexible.

Ram returns normal, fast forward normal, manual cannot slow down, bending weak.

Solutions:

  • Check whether the reversing valve, which controls the oil circuit, is working properly. If so, it causes the flling valve is not closed, so that the upper chamber and the tank flling port connected, cannot build pressure. The reason why the valve does not work properly is that it is not energized or stuck.
  • Check whether the flling valve is stuck, if so, please clean the flling valve, reinstalled, so that the spool flexible.

The ram return speed is too slow.

Causes:

  • The malfunction like high return pressure is mainly because the flling valve is not open. This phenomenon is just contrary to the logical of above malfunction 3.

Solutions:

  • This can be handled by referring to the solution of the malfunction 3

Y1 axis and Y2 axis position deviation exceed the allowed synchronization deviation distance, the ram cannot move up and down.

Causes:

  • This type of failure is mainly because before we shut down the press brake machine, the ram is not placed in the upper and lower mold contact position and power off, at this time due to the fall of punch, the real position at both ends of Y1, Y2 axis exceeds the limit. It is necessary to adjust the actual position of the Y1 axis Y2 axis at both ends. The controller should display the current value of the position. Then the press brakes can be operated normally.

Solutions:

  • Increase the data in the controller of CNC press brake machine for 5mm on the original basis, then enter into manual mode, manual down, the system will automatically correct the location and return to normal work.