Views: 38 Author: DURMAPRESS Publish Time: 2020-11-02 Origin: DURMAPRESS Inquire
Quality has always been the face of a product. How to improve quality depends on the master's operating skills and the quality of production equipment. How to solve the large bending angle error of wc67k series cnc hydraulic press brake?
1 .Check whether the compensation deflection of the compensation cylinder of the wc67k series cnc hydraulic press brake is large and the zero position cannot be completely restored
2. Check whether the quick clamp of the wc67k series cnc hydraulic press brake is loose
3. Check whether the bottom dead center of the wc67k series cnc hydraulic press brake changes every time
4. Check whether the bow plate installation of the e21 press brakeis standard, and whether the screw hole is top dead
5. Changes in the plate itself of the wc67k series cnc hydraulic press brake (thickness, material, stress)
6. Is the grating ruler of wc67k series cnc hydraulic press brake loose?
7. The positioning accuracy of the wc67k series cnc hydraulic press brake is inaccurate: Wuxi Shenchong feels whether the zero offset value of the proportional valve is appropriate, and the positioning cannot reach the bottom dead center, making it impossible to return
The size control method of the wc67k series cnc hydraulic press brake during bending:
1. To avoid the accumulation of errors, measure the unfolded size for each folding process;
2. Avoid using the wc67k series cnc hydraulic press brake to lean in position, and avoid lean in a large angle;
3. Products whose edges must be bent by the wc67k series cnc hydraulic press brake, and the previous bending angle should be slightly less than 90 degrees;
4. Determine the accuracy of the measuring tool before processing;
5. Do the first inspection before the formal processing, and do the inspection during the processing;
6. The wc67k series cnc hydraulic press brake selects the appropriate machine according to the accuracy requirements of the processed product;
7. Avoid choosing different tools, make sure that the tip of the upper die is on the same straight line before processing;
8. Choose a good processing method and a good process layout method to simplify the processing difficulty;
9. The position of the bending machine is accurate, and any abnormal position needs to be detected immediately.
Problems that should be paid attention to when buying a high quality press brake
Problems that should be paid attention to when purchasing a bending machine:
Once an improper selection is made when purchasing a bending machine, the production cost will rise, and the bending machine cannot be expected to recover the cost. Therefore, choosing a good product is the first choice. The bending machine produced by Maanshan Durmapress Machinery Techology Co.,Ltd is mainly used for production, with excellent quality and after-sales guarantee. When choosing a bending machine, there are several factors that must be considered in the decision-making process:
The first important thing to consider is the parts you want to produce. The point is to buy a machine that can complete the processing task with the shortest workbench and the smallest tonnage. Carefully consider the material grade and the maximum processing thickness and length. If most of the work is low carbon steel with a thickness of 16 gauge and a maximum length of 10 feet (3.048 meters), then the free bending force does not need to be greater than 50 tons. However, if you are engaged in a large number of bottomed die forming, perhaps a 160-ton machine tool should be considered.
Assuming that the thickest material is 1/4 inch, a 10-foot free bending requires 200 tons, and a bottomed die bending (correction bending) requires at least 600 tons. If most parts are 5 feet or shorter, the tonnage is almost halved, which greatly reduces the cost of purchase. The length of the part is very important for determining the specifications of the new machine.
Under the same load, the deflection of the worktable and sliding block of the 10-foot machine is 4 times that of the 5-foot machine. This means that shorter machines require fewer shim adjustments to produce qualified parts. Reduced shim adjustment and shortened preparation time.
Material grade is also a key factor. Compared with low-carbon steel, the load required for stainless steel is usually increased by about 50%, while most grades of soft aluminum are reduced by about 50%. You can get the machine's tonnage table from the bending machine manufacturer at any time. The table shows the estimated tonnage required per foot in different thicknesses and different materials.
3, bending radius
When free bending is used, the bending radius is 0.156 times the die opening distance. During the free bending process, the opening distance of the die should be 8 times the thickness of the metal material. For example, when using 1/2 inch (0.0127 m) opening distance to form 16 gauge low carbon steel, the bending radius of the part is about 0.078 inches. If the bending radius is almost as small as the thickness of the material, a bottomed die must be formed. However, the pressure required for forming a bottomed die is about 4 times greater than that of free bending. If the bending radius is smaller than the thickness of the material, a punch with a front-end fillet radius smaller than the thickness of the material must be used and the imprint bending method must be used. In this way, 10 times the pressure of free bending is required.
As far as free bending is concerned, punch and die are processed at 85° or less (smaller is better). When using this set of molds, pay attention to the gap between the male mold and the female mold at the bottom of the stroke, and the excessive bending that is sufficient to compensate for the springback and keep the material at about 90°. Generally, the springback angle of the free bending die on the new bending machine is ≤2°, and the bending radius is equal to 0.156 times the opening distance of the die.
For the bending of bottomed concave molds, the mold angle is generally 86 ~ 90°. At the bottom of the stroke, there should be a gap slightly larger than the thickness of the material between the male and female molds. The forming angle is improved because the bottomed die has a larger bending tonnage (about 4 times that of free bending), which reduces the stress that usually causes springback in the bending radius.
The imprint bending is the same as the bending of the bottomed die, except that the front end of the punch is processed to the required bending radius, and the gap between the punch and the die at the bottom of the stroke is smaller than the material thickness. Since enough pressure (approximately 10 times of free bending) is applied to force the front end of the punch to contact the material, springback is basically avoided.
In order to choose the lowest tonnage specification, it is best to plan for a bending radius larger than the material thickness, and use the free bending method as much as possible. When the bending radius is large, it often does not affect the quality of the finished part and its future use.
Bending accuracy requirements are a factor that needs to be carefully considered. It is this factor that determines the need to consider a CNC bending machine or a manual bending machine. If the bending accuracy is required to be ±1° and cannot be changed, the CNC machine must be focused.
The repeatability of the slider of the wc67k series cnc hydraulic press brake is ±0.0004 inches, and the precise angle of forming must use such precision and a good mold. The repeatability of the slide block of the manual bending machine is ±0.002 inches, and the deviation of ±2~3° is generally produced under the condition of using a suitable mold. In addition, the CNC bending machine is ready for rapid mold assembly. When many small batches of parts need to be bent, this is an indisputable reason for consideration.
Even if there are shelves full of molds, don't assume that these molds are suitable for newly purchased machines. Must check accessories
The wear of the mold is measured by measuring the length from the front end of the punch to the shoulder and the length between the shoulder of the female mold. For conventional molds, the deviation per foot should be about ±0.001 inches, and the total length deviation should not be greater than ±0.005 inches. As for the precision grinding mold, the accuracy per foot should be ±0.0004 inches, and the total accuracy should not be greater than ±0.002 inches. It is best to use fine grinding molds for CNC bending machines, and conventional molds for manual bending machines.
6, the side length of the bent part
Assuming that it is bent 90° along a 5×10-foot 10-gauge low-carbon steel plate, the bending machine must apply an additional 7.5 tons of pressure to lift the steel plate up, and the operator must prepare for the 280-pound straight edge drop . It may require several strong workers or even a crane to manufacture this part. Operators of bending machines often need to bend long-side parts without realizing how strenuous their work is.