The classification of molds depends on the different materials formed.
Hardware mold, plastic mold and its special mold.
Hardware dies are divided into: punching dies (such as punching dies, bending dies, stretching dies, hole-turning dies, shrinking dies, wavy dies, bulging dies, shaping dies, etc.). ), forging die (such as forging die, upsetting die, etc. ), extrusion die, extrusion die, die casting die, forging die, etc.
Non-metallic molds are divided into plastic molds and inorganic non-metallic molds. According to the different materials of the mold itself, the mold can be divided into sand mold, metal mold, vacuum mold, paraffin mold and so on. Among them, with the rapid development of polymer plastics, plastic molds are closely related to people's lives. Generally, plastic molds can be divided into injection molds, extrusion molds and gas-assisted molding molds.
Basic knowledge of mold design 88 1, common plastic engineering materials and shrinkage?
ABS:0.5% (unbreakable rubber)
Pc:0.5% (bulletproof glass glue)
PMMa:0.5% (plexiglass)
Polyethylene: 2% polyethylene
Polystyrene: 0.5% (polystyrene)
Polypropylene: 2% (100% soft rubber)
Nylon: 2% (nylon)
PVC: 2% (PVC)
Polyformaldehyde: 2% (plug steel)
ABS+PC:0.4%
PC+ABS :0.5%
Engineering material: ABS PC PE POM PMMA PP PPO PS PET
2. How many systems is the mold divided into?
Pouring ejection? Cooling? Molding? unleash
3. What problems should be paid attention to in the process of mold design?
(1) The wall thickness should be as uniform as possible, and the demoulding slope should be large enough.
(2) The transition part should be smooth and smooth to prevent sharp corners.
(3) the gate. The runner should be as wide and short as possible, and the gate position should be set according to the shrinkage and condensation process, and the cooling well should be added if necessary.
(4) The surface of the mold should be smooth with low roughness (preferably 0.8).
(5) Exhaust holes and grooves must be enough to exhaust air and gas in the melt in time.
(6) Except for PET, the wall thickness should not be too thin, generally not less than 65438 0 mm. 。
4. What are the common defects of plastic parts?
Lack of glue? Cloak? Bubbles? Shrinkage? Welding marks? Black spots? Stripes? Tilt up? Hierarchy? shed a skin
5, commonly used plastic mold steel?
45# S50c 7 18 738 7 18H
738H P20 23 16 8407 H 13
nak 80 nak 55s 136s 136h SKD 6 1
6. What steel is used for high mirror polishing?
Commonly used high hardness heat-treated steels, such as SKD6 1, 8407, S 136.
7. What is the structure of the template?
Panel? A board? B board? Square iron? Guide? Thimble disk? Thimble fixing plate? sole
8. What are the basic forms of parting surface?
Straight man? Tilt? Surface？ Vertical? cambered surface
9. How to hide each other in UG?
CtrL+B or ctrL+shift+B
10, what are the mold processing machinery and equipment?
Computer gong? Lathe? Milling machine? Grinder? Drilling machine
1 1. What are 2D and 3D?
D is the prefix of dimension, 2D refers to two-dimensional plane, and 3D refers to three-dimensional space. In the mold part, 2D usually refers to the plan, that is, the CAD drawing, and 3D usually refers to the stereoscopic drawing.
What is the default precision of 12 and pro/e? What is the default precision of UG?
The default precision of pro/e is 0.00 12MM, and that of UG is 0.0254MM.
13, the top four enterprises in the world in terms of mold base output?
Germany: HASCO Japan: Shuang Ye (Shuang Ye) USA: DME China: LKM (Ji Long)
14. What is the default word height of CAD?
The default word height of CAD is: 2.5 mm
15, what is touching and what is inserting?
The mating surface of the male die and female die parallel to the PL plane is called the contact surface, and the mating surface of the male die and female die not parallel to the PL plane is called the insertion surface.
16, the relationship between sliver and silk
Stripe and silk are both units of length. Stripe 1 =0.0 1MM in Taiwan Province Province and silk 1 =0.0 1MM in Hong Kong, so 1 = 1.
17, where is the pillow?
There is often a gap on the edge of the plastic part of the shell for installing various accessories. The pillow-shaped parting part formed here is called pillow position.
18, what is a crater?
The shape of the root of BOOS column reflected in mold is called mold crater after volcanic eruption.
19, what do you mean?
Oh, it refers to the core, a Hong Kong idiom.
20. What is a tiger's mouth?
The tiger's mouth is also called: pipe position, that is, the part used for limiting.
2 1, what is ranking?
The product layout on the mold is called ranking.
22. What is the glue position?
The cavity of the product on the mold is called the glue position.
23. What is the bone position?
The tendon on the product is called bone position.
24. What is the column position?
The column of BOSS on the product is called column position.
25. What is a virtual location?
The gap in the mold is called a virtual position.
26. What is the buckle position?
The hook used for connection on the product is called the buckle position.
27. What is the fire mode?
The pattern left after EDM is called fire pattern.
28. What PL surface?
PL surface, also known as parting surface and Lamian Noodles, refers to the part where the front die and the back die contact when clamping.
29. What is a computer gong?
CNC milling machine and machining center
30. What is a copper worker?
EDM usually uses easy-to-process copper material as discharge electrode, which is called copper worker, also known as electrode. Copper workers are generally divided into rough workers, rough young workers, young workers and young workers, also known as Seiko.
3 1. What is the spark position?
In the process of discharge, the discharge gap between copper workers and steel materials is called spark potential, and the spark potential of rough workers is generally 10 to 50, and that of young workers is generally 5 to 15.
32. What is the material level?
Avoid the thickness of plastic products, also known as thick meat.
33. What is the original body?
The retain force of that original body is relative to the cutting insert. Original body retention means that the whole piece of steel is a processing blank and is processed together during processing.
34. What are the welding marks?
The line formed when two strands of plastic meet is called weld mark.
35. What is a jet plane?
After the plastic enters the cavity from the glue inlet, it forms a serpentine flow mark, which is called jet.
36. what does LKM mean
LKM refers to Ji Long moldy embryos, and commonly used moldy embryos are: LKM, Fordba, Li Ming, Huansheng, Changhui and Desheng.
37. What does DME mean and what does HASCO mean?
DME and LKM are standard parts, DME is made in America, and HASCO is made in Europe.
38. What is reverse buckle?
Parts of products that cannot be directly demoulded by the front and rear molds become inverted.