Types of Hydraulic Bending Machine Dies and Discussion on Proper Die Selection
During the operation of a hydraulic bending machine, faults may occur, such as a lack of pressure. What could be the reasons for a hydraulic bending machine to have no pressure? The lack of pressure in a hydraulic bending machine can be caused by abnormalities in the large hydraulic control valve spring, internal leakage in the cylinder, inaction of the solenoid valve spool, and other factors. Below, we will specifically discuss the reasons for the lack of pressure in a hydraulic bending machine and methods for pressure adjustment.
I. Reasons for the Lack of Pressure in a Hydraulic Bending Machine
Insufficient pressure during the operation of a hydraulic bending machine can affect the quality of the processing. It is important to promptly identify and resolve the issue. The lack of pressure in a hydraulic bending machine can be caused by various factors. We can analyze and eliminate the following possibilities:
1. Check for any abnormalities in the large hydraulic control valve spring and replace it if necessary.
2. Check for internal leakage in the cylinder. If leakage is detected, replace the cylinder seals and adjust the stroke of the hydraulic bending machine cylinder to ensure consistent travel for both left and right cylinders.
3. Inspect the relief valve of the hydraulic bending machine. Check if the relief valve has excessive backflow and if there are any blockages. Remove and clean the relief valve, and adjust the relief valve setting.
4. Check if the solenoid valve spool is functioning properly. If it is not moving, remove and clean it, making sure to reinstall it correctly.
5. Inspect the electrical contactors of the hydraulic bending machine to ensure proper connections and check for any looseness or detachment.
If all the above points have been checked and no issues are found, it may indicate a faulty oil pump in the bending machine. In such cases, it is recommended to seek assistance from professional maintenance personnel.
II. Adjusting the Pressure in a Hydraulic Bending Machine
1. Adjustment of the upper limit of the slide: Adjust the position of the collision block II to make the rising slide stop at the desired top dead center position. This shortens the interval of the slide stroke, reduces the working cycle time, and improves productivity.
2. Adjustment of the slow speed motion of the slide: When the slide is descending, the collision block "I" triggers the stroke switch to enable slow speed motion of the slide. The duration of the slow speed stroke is adjusted by a potentiometer.
3. Adjustment of the clearance between the upper and lower dies (with the slide stopped at top dead center):
a. Use the buttons on the control panel to adjust the initial clearance, which should be greater than the material thickness. Adjust the clearance based on the angle of the workpiece. Fine adjustments can also be made using the handwheel, with the adjustment value displayed on the calculator. Each increment or decrement of a single digit represents 0.1mm.
b. If there is no difference in the workpiece angle at both ends, loosen the supporting pin and move the connecting rod to the left to disengage the left and right rotating connections. Use the handwheel to adjust the distance of one mechanical limit position, achieving precise adjustment of the workpiece angle at one end.
c. If the workpiece angles differ at both ends but are consistent in the middle, a micro-adjustment can be made to the upper die. When using the micro-adjustment, bring the upper die close to the lower die groove, slightly loosen the screws on the upper die connection plate and adjustment block, and adjust the adjustment wedge on the upper part of the middle section. Adjust the upper die to protrude slightly in the middle section, tighten the supporting pin, and test the bending until the angle of the entire workpiece reaches the allowable value.
4. Adjustment of the bending force in the hydraulic bending machine: Calculate the bending force of the sheet metal using a gauge or the bending force calculation formula and determine the corresponding pressure value (P) based on the calculation. Then adjust the handwheel of the relief valve 8 to generate a force slightly greater than the calculated bending force.
5. Adjustment of the backgauge clearance: The backgauge is used for lengthwise positioning during sheet metal bending. It is controlled by buttons on the front control panel to adjust the electric motor. The adjustment value can be read from the conversion table on the control panel, with a conversion value of 0.1mm/revolution, and fine adjustments can be made using the handwheel.
During the operation of a hydraulic bending machine, faults may occur, such as a lack of pressure. What could be the reasons for a hydraulic bending machine to have no pressure? The lack of pressure in a hydraulic bending machine can be caused by abnormalities in the large hydraulic control valve spring, internal leakage in the cylinder, inaction of the solenoid valve spool, and other factors. Below, we will specifically discuss the reasons for the lack of pressure in a hydraulic bending machine and methods for pressure adjustment.
I. Reasons for the Lack of Pressure in a Hydraulic Bending Machine
Insufficient pressure during the operation of a hydraulic bending machine can affect the quality of the processing. It is important to promptly identify and resolve the issue. The lack of pressure in a hydraulic bending machine can be caused by various factors. We can analyze and eliminate the following possibilities:
1. Check for any abnormalities in the large hydraulic control valve spring and replace it if necessary.
2. Check for internal leakage in the cylinder. If leakage is detected, replace the cylinder seals and adjust the stroke of the hydraulic bending machine cylinder to ensure consistent travel for both left and right cylinders.
3. Inspect the relief valve of the hydraulic bending machine. Check if the relief valve has excessive backflow and if there are any blockages. Remove and clean the relief valve, and adjust the relief valve setting.
4. Check if the solenoid valve spool is functioning properly. If it is not moving, remove and clean it, making sure to reinstall it correctly.
5. Inspect the electrical contactors of the hydraulic bending machine to ensure proper connections and check for any looseness or detachment.
If all the above points have been checked and no issues are found, it may indicate a faulty oil pump in the bending machine. In such cases, it is recommended to seek assistance from professional maintenance personnel.
II. Adjusting the Pressure in a Hydraulic Bending Machine
1. Adjustment of the upper limit of the slide: Adjust the position of the collision block II to make the rising slide stop at the desired top dead center position. This shortens the interval of the slide stroke, reduces the working cycle time, and improves productivity.
2. Adjustment of the slow speed motion of the slide: When the slide is descending, the collision block "I" triggers the stroke switch to enable slow speed motion of the slide. The duration of the slow speed stroke is adjusted by a potentiometer.
3. Adjustment of the clearance between the upper and lower dies (with the slide stopped at top dead center):
a. Use the buttons on the control panel to adjust the initial clearance, which should be greater than the material thickness. Adjust the clearance based on the angle of the workpiece. Fine adjustments can also be made using the handwheel, with the adjustment value displayed on the calculator. Each increment or decrement of a single digit represents 0.1mm.
b. If there is no difference in the workpiece angle at both ends, loosen the supporting pin and move the connecting rod to the left to disengage the left and right rotating connections. Use the handwheel to adjust the distance of one mechanical limit position, achieving precise adjustment of the workpiece angle at one end.
c. If the workpiece angles differ at both ends but are consistent in the middle, a micro-adjustment can be made to the upper die. When using the micro-adjustment, bring the upper die close to the lower die groove, slightly loosen the screws on the upper die connection plate and adjustment block, and adjust the adjustment wedge on the upper part of the middle section. Adjust the upper die to protrude slightly in the middle section, tighten the supporting pin, and test the bending until the angle of the entire workpiece reaches the allowable value.
4. Adjustment of the bending force in the hydraulic bending machine: Calculate the bending force of the sheet metal using a gauge or the bending force calculation formula and determine the corresponding pressure value (P) based on the calculation. Then adjust the handwheel of the relief valve 8 to generate a force slightly greater than the calculated bending force.
5. Adjustment of the backgauge clearance: The backgauge is used for lengthwise positioning during sheet metal bending. It is controlled by buttons on the front control panel to adjust the electric motor. The adjustment value can be read from the conversion table on the control panel, with a conversion value of 0.1mm/revolution, and fine adjustments can be made using the handwheel.
