1, the characteristics of stamping process?
Answer: advantages: good interchangeability; get thin wall, light weight, good rigidity, high surface quality, the complex shape parts; energy saving; high efficiency.
Disadvantages: noise and vibration; mold high requirements, manufacturing complex, long period, high manufacturing cost; the high precision of parts, stamping production is difficult to meet the requirements of.
2, separation steps: blanking punching cutting trimming die cutting
The forming process: bending drawing flanging necking bulging extruded coil flared shape correction
3, stamping process is divided into the two classes? What is the difference between them?
Answer: stamping process is divided into separation process and the forming process.
The difference: separation process: the stamping and sheet separated from each other on the certain contour line process in stamping process.
The forming process: blank plastic deformation without destroying the conditions to form the demand, the shape and dimension precision of parts.
4, the characteristics of cold stamping processing?
Answer: cold stamping is less, stamping parts without one chip processing method of cutting the general no longer processing.
Cold stamping is a kind of efficient method for processing.
Stamping parts quality and stability of cold stamping income, good interchangeability of.
Cold stamping processing of thin wall, light weight, good rigidity, the complex shape parts of.
5 basic requirements, the pressing process of the sheet includes the aspects?
Answer: 1 mechanical performance requirements: Generally speaking, high elongation rate, ratio of yield strength, elastic modulus, hardening index, coefficient of normal anisotropy in.
for all kinds of stamping forming process         2 chemical composition requirements: 2 the microstructure of surface quality requirements of 3 4 material thickness tolerance requirements.
6, strain rate effect on plastic deformation?
Answer: 1. The deformation velocity increased, the deformation resistance increases, the intergranular brittle fracture occurred 2 due to thermal effects caused by temperature, metal, plastic and improved metal.
7, what is the yield point “ ” ” &ldquo? Yield point; impact?
Answer: “ yield; yield platform “ the lowest point out the corresponding stress condition.
Effect: the material yield point is small, easy material yield, small springback after forming, and setting a good film.
Effect on the surface quality of the parts: tension curves yield platform, yield large elongation, sheet in yield elongation, surface slip line clear traces, causing parts of the surface roughness.
8, the lug coefficients Δ r had any effect on the drawing process?

        plane direction 2 plate is large, in the drawing, flanging, uneven can cause deformation bulging, the stamping process, the results can not only because of the local deformation is too large, but the overall ultimate deformation is reduced, but also may cause wall thickness and lower quality stamping parts, in the production should reduce the lug coefficient.
9, the blanking section which of these parts? How blanking gap size influenced the part?
Answer: the gap is too small, resulting in fillet becomes small, bright band broadening, fracture zone becomes small, little burr: the gap is too large, resulting in fillet becomes large, bright with narrow, section angle becomes larger, burr; J gap size small, rounded, bright belt about material thickness 1/3~2/3, fault Zone small, little burrs; gap size is moderate, but uneven, the gap is too small at the crowded hair, the gap is too large elongated burr.
10, analysis of the impact of state blanking section quality of the punch and die cutting edge?
Answer: when the die cutting edge blunt, in the blanking edge will have a lot of burr, when the convex die cutting edge blunt,
It will produce the burr in the punch edge; when the die cutting edge blunt, it will produce the burr in the blank; when the punch and die cutting edge is blunt, it will have the edge burr blanking.
11, analysis of the blanking clearance blanking dimension
The accuracy of the impact?
Answer; the blanking workpiece stress and elastic deformation produced by the end of the workpiece, blanking, elastic recovery phenomenon, causing the blanking piece and the punch and die cutting edge size does not match; when the gap is too large, blank size, punching parts size increases; when the gap is too small, blank size decreases; when the gap is reasonable, the size and die cutting edge size exactly the same.
What are the factors that influence 12, punching parts size precision and surface quality? How to improve the dimensional accuracy and surface quality?
Answer: the factors affecting the size precision punching blanking: blanking clearance, manufacturing accuracy of the die, the thickness and material properties, shape and size of punching cutting.
  improve the dimensional precision of measures:
1 die precision stamping precision IT3~4 stage
2 choose soft stamping materials
3 reasonable choice of blanking clearance 4 punching parts try to design simple, symmetrical. Factors affecting the quality of the section: the material properties; blanking clearance; punch and die cutting edge state.
  improve the profile quality measures:
1 choose good plasticity material
2. Choice of blanking clearance
reasonable 3 punch to keep sharp edge.
13, the blanking clearance of unloading force, push force, influence the top pieces?
Answer: the gap increases, the material the tensile stress increases, material is easy to fracture separation, the blanking bright