Press brake stroke
How to calculate press brake stroke length
Press brake application
Press brakes are widely used in energy, transportation, automobile, machinery, metallurgy, shipbuilding, aviation, military, agricultural machinery, petroleum machinery, power generation industries.
Press brake toolings
Press brake standard toolings including punch and die, for the stamping and separation of sheet metal. The die for forming has a cavity, while for separation it has blade edge.You can check the ultimate guide for press brake toolings first.
Commonly used press brake toolings
In order to extend the service life of mold, the press brake punch and dies are designed with rounded corners as far as possible. Commonly used press brake toolings are as follows.
generally, the height of flanged edge L≧3t(t=plate thickness). if the height of flanged edge is too small, even use bending mold is not conducive to forming.
See also:
Non-indentation bending technology and die application
Determinants of press brake toolings accuracy and angle.
Press brake toolings materials
Generally, the materials of press brake toolings including T8 steel, T10 steel , 42CrMo,and Cr12MoV.
Cr12MoV is also a good material. The using performance can be satisfied, the process performance is also good. But the price will be high.
42CrMo is a high strength alloy quenched and tempered steel with high strength and strong toughness. It can work under the temperature of -500 degree.
It mainly requires high strength, high toughness, and good wear resistance.
See also:
Press brakes toolings materials selection and performance features.
How to choose press brake toolings
See:
How to choose press brake die
Top 10 considerations when using press brake toolings
Press brake toolings pictures
Press brake toolings drawings
Press brake punch point radius(R) and punch angles
Commonly used punch radius including:
Punch angles:
Generally, for plate below 3mm with R0.6 standard punch, the point angles have:
The dihedral angle of punch should less than fabrication angle. For example, if we bending work piece with 90 degree, the punch with 88 degree point angle should be chosen.
Press brake dies shape
Generally, press brake dies have single-V shape and double-V shape, among these shapes, it also has separation die and full-length die. Different dies are suitable for different fabrication purpose.
In short, the single-v die has much wider application than double-V die, while separation die has wider application than full-length die.
Die V width and V dihedral angle
V width:
The relationship between V width and plate thickness(T):
The factors that affect the resilience and the measures to reduce the spring back:
Mechanical properties of the material
The spring back angle is proportional to the yield point of the material and is inversely proportional to the elastic modulus E. in order to reduce the spring back for those sheet metal which requires high precision, the low carbon steel should be the first consideration, do not choose high carbon steel and stainless steel.
The larger the relative bending radius r/t, the smaller the degree of deformation, the greater the rebound angle.
This is one very important concept, in the case of material properties permitting, the small bend radius should be chosen to improve accuracy. In particular, attention should be made to avoid designing large arcs as much as possible,as shown in the following figure. Such large arcs have a greater impact on production and quality control:
Press brake dies cabinet