Bending Machine-How to choose the bending machine?

Bending Machine-How to choose the bending machine?

Bending machine purchase factors:
Once the buy inappropriate choice of bending machine, production costs will rise, bending machine can not expect to recover the costs. Therefore, there are several factors that must be weighed in the decision-making.◆ parts: The first important issue worth considering is the production of parts you want, point is to buy a table to complete the processing tasks and the shortest, smallest tonnage of the machine. Careful consideration of material grades and maximum processing thickness and length. If most of the work is the thickness of 16 gauge, 10 feet maximum length of mild steel, then the free bending force does not have to be greater than 50 tons. However, if engaged in a lot of bottom forming die, and perhaps should consider a 150 tonnage machines. Well, assuming that most of the material thickness is 1 / 4 inch, 10-foot free bending of 165 tons, while the bottom die bending (bending correction) at least 600 tons. If most of the work piece is 5 feet or less certain, almost half the tonnage, thereby significantly reducing cost of ownership. Part in determining the length of the specifications of the new machine is very important.
◆ Flexible change: You have to consider this machine changes that may occur scratch. In the same load, 10 feet machine table and change the slider there is five feet of flexible machine four times. This means that, short of the machine requires less shimming, can produce quality parts. Reduce the shimming and reduces preparation time. Grade material is also a key factor. Compared with low-carbon steel, stainless steel load typically requires an increase of 50%, while most brands of soft aluminum by 50 percent. You can always get from the bending machine manufacturers tonnage of the machine table, the table shows the different thicknesses, different materials required under each foot length of the tonnage estimate.
◆ parts of the bending radius: then, should focus on the parts of the bending radius. Free-bending, bending radius of 0.156 from the die opening times. In the free bending process, the die opening is away from the metal thickness should be 8 times. For example, use 1 / 2 inch opening formed from 16 gauge mild steel, the parts of the bending radius of about 0.078 inches. If the bending radius is almost as small as the thickness of material required to carry out bottom forming die. However, the bottom die forming pressure required is four times larger than the free bending around. If the bend radius is less than the material thickness, shall be less than the material thickness of the front radius of the punch, and resort to stamping bending. In this way, we need 10 times the free bending stress. The free bending, the punch and die at 85 ° or less than 85 ° processing (little something for the good). When using this set of molds, pay attention to the punch and the die gap at the bottom of the stroke, and resilient enough to compensate for leaving the material remains of about 90 ° bend over. Typically, the free bending mode in the new bending machine to generate the rebound angle ≤ 2 °, bending radius equal to the die opening of 0.156 times the distance. For the bottom bend die, die angle is generally 86 ~ 90 °. In the bottom of the trip, between the punch and die should be a slightly larger than the thickness of the gap. Forming the angle can be improved, because with bottom bending tonnage die larger (about four times the free bending), reducing the bending radius is usually caused by rebound stress. Stamping bending and bottom bending die the same, but the punch has become the front-end processing needs of bend radius, and stroke at the bottom of the punch and die clearance is less than the material thickness. Because exert enough pressure (about 10 times the free bending) force the punch front contact materials, basically to avoid the rebound. In order to choose the lowest number of tons of specifications, preferably greater than the thickness of the bending radius for the plan, and as far as possible free-bending. Bending radius is large, often into pieces does not affect the quality of its future use.
◆ degree: bending accuracy is a need to carefully consider the factors, it is this factor, the decision you need to consider a CNC bending machine or manual bending machine. If the bending accuracy ± 1 ° and can not be changed, you must focus on the CNC machine. CNC bending machine slide repeatability is ± 0.0004 inches, forming the angle shall be so precise accuracy and good mold. Manual bending machine slider repeat accuracy of ± 0.002 inches, and mold in the use of appropriate conditions will generally ± 2 ~ 3 ° of deviation. In addition, CNC bending machine to prepare for the rapid loading mode, when you need to bend many small-volume parts, this is considered an unquestionable reason.
◆ Die: Even if you have a shelf full of mold, mold for those that do not buy a new machine. Must check the wear of each mold, the method is to measure front-to-shoulder punch and die length between shoulder length. For the conventional mold, per foot deviation should be ± 0.001 inches, and the total length of the deviation is less than ± 0.005 inches. As for the grinding mold, per foot accuracy is ± 0.0004 inches, no larger than the total accuracy of ± 0.002 inches. Best to die for CNC bending machine grinding, conventional mold for manual bending machine. Indeed, we often made only to buy and not buy a new press brake tooling suitable accompanying error.
◆ side bending parts: an often overlooked factor is the material in front of the curved bending side. Suppose along a 5 × 10-foot 10-gauge carbon steel bent 90 °, bending machine is probably an additional 7.5 tons applied pressure to the top plate up, and the operator must be 280 pounds to prepare for the whereabouts of the straight edge . Manufacture of the part may require several able-bodied workers and even a crane. Bending machine operators often need to bend the long side parts, but unaware of how strenuous their jobs. There is a feeding device for care work in this workshop, which may be based on old and new machines need to be improved. Use of the device, forming the long side parts only one operation.