The main issues for design engineers to consider are the following:
Bend
1.1 minimum flanging: not less than 4 times the thickness of the plate, below this limit, may lead to greatly increased processing difficulty, or even can not be processed, at this time, should communicate with the process engineer.
1.2 bending causes the hole to deform: if the hole is too close to the bending line, it may be pulled out of shape by the die.
1.3 since bending is often determined on a case-by-case basis, the necessary communication with the process engineer can greatly improve design efficiency.
2. Pu Chong
Where possible, standardization, consistency, reduce mold costs and shorten the proofing cycle.
3. Fitter
Countersunk Hole: should pay attention to the plate thickness is not less than the height of the countersunk head screw head, otherwise the screw head will be higher than the plate, resulting in unstable fixation.
4. Press riveting
4.1 When the plate thickness is less than 1mm, it may cause the riveting parts to fall off easily.
4.2 The relation between riveting screw and plate thickness
| Plate Thickness | 1.0-2.0mm | 2.0-2.5mm | >2.5mm |
| Screw Specification | M5 Below | M6 | M8 |
4.3 Too much edging of rivets has two consequences:
- after pressing rivets, the edge of the plate will deform (the edge will bulge), and the hole position will shift 0.1-0.5 mm to the edge;
- press riveting position too close to the fold will lead to press riveting die can not press down: press riveting head outside edge to the fold distance: not less than 3mm.
4.4 U-shaped bending parts press riveting should take into account whether the press riveting die can be attached to the workpiece, other parts with relatively narrow internal space if the inner side presses riveting, should take into account this problem.
4.5 Clinching Fasteners specifications are as uniform as possible, to facilitate supplier orders, shorten the proofing cycle, and also reduce the probability of press rivets error.
5. Welding
5.1 for narrow internal space of the workpiece if the inner side of the welding, should consider how the welding torch into.
5.2 when the plate thickness is less than 1mm, it is easy to produce shrinkage or Burn-through after welding, and the deformation caused by welding is larger.
5.3 the welding of copper, aluminum, and other materials is more difficult and requires a higher technical level of welders.
6. Spray
There are three main types of spraying (each including indoor and outdoor) :
Smooth: can be divided into Matt, Smooth, Bloom, spray coating thickness of about 60-90 μm, after about 90-120 μm.
Sand Grain: can be divided into the fine sand grain, coarse sand grain, and spray coating thickness of about 50-80 μm, after about 80-110 μm.
Tangerine Grain: can be divided into small tangerine grain, big tangerine grain, spray coating thickness of about 90-120 μm, after about 120-150 μm.
The thickness of the spray coating at the position where the workpiece is easy to accumulate powder will exceed the above-mentioned thickness.
Smooth: the appearance is more beautiful, screen printing effect is good, disadvantages: Spray cost is high, spray rework rate is high, very easy to scratch, and scratch the surface can not be repaired, and Bloom’s spray is the most difficult.
