1. Commonly used plastic engineering materials and shrinkage rate?

ABS: 0.5% (super non-breaking glue) pc: 0.5% (bullet-proof glass glue) PMMa: 0.5%: (plexiglass) pe: 2% polyethylene PS: 0.5% (polystyrene) pp: 2% (100 Folding soft rubber) PA: 2% (nylon) PVC: 2% (polyvinyl chloride) POM: 2% (plug steel) ABS+PC: 0.4% PC+ABS: 0.5%

　　Engineering materials: ABS, PC, PE, POM, PMMA, PP, PPO, PS, PET

　　2. How many systems are the molds divided into?

　　 pouring → ejection → cooling → molding → exhaust

　　 3. What problems should be paid attention to in the process of mold design?

　?、賂he wall thickness should be as uniform as possible, and the draft angle should be large enough.

　　②The transition part should be gradual, smooth transition, and avoid sharp corners.

　?、跥ating. The runner should be as wide as possible, thick and short, and the gate position should be set according to the shrinkage condensation process, and a cold well should be added if necessary.

　?、躎he surface of the mold should be smooth, with low roughness (preferably lower than 0.8)

　?、軹he vent hole and groove must be sufficient to discharge the air and gas in the melt in time.

　?、?Except for PET, the wall thickness should not be too thin, generally not less than 1mm.

　　 4. What are the common defects of plastic parts?

　　 lack of glue→cloak→bubble→shrinkage→weld line→black dots→stripe→lifting→delamination→peeling

　　 5. What is the commonly used plastic mold steel?

　　45#S50c718738718H

　　738HP2023168407H13

　　NAK80NAK55S136S136HSKD61

　　 6. Which type of material is used for high mirror polishing?

　　 Commonly used high-hardness heat-treated steel, such as: SKD61, 8407, S136

　　7. What are the structures of the mold base?

　　Panel→A plate→B plate→square iron→guide post→thimble plate→thimble fixing plate→bottom plate

　　 8. What are the basic forms of parting surface?

　　Straight→Slanted→Curved→Vertical→Curved

　　 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→Grinding machine→Drilling machine

　　 11. What is 2D and what is 3D?

　　D in English is: the prefix of Dimension (line degree, dimension), 2D refers to a two-dimensional plane, 3D refers to a three-dimensional space, in the mold part, 2D usually refers to a plan view that is a CAD drawing, and 3D usually refers to a three-dimensional view.

　　12. What is the default precision of pro/e? What is the default precision of UG?

　　The default precision of pro/e is 0.0012MM, and the default precision of UG is 0.0254MM.

　　 13. The top four global mold base manufacturers?

　　Germany: HASCO Japan: FUTABA (Futaba) America: DME China: LKM (Long Kee)

　　14. What is the default character height of CAD?

　　CAD default character height is: 2.5MM.

　　 15. What is bumping and penetrating?

　　The male and female mold fitting surface parallel to the PL surface is called the piercing surface, and the male and female mold fitting surface that is not parallel to the PL surface is called the insertion surface.

　　 16, the relationship between strips and silk

　　 bar and silk are units of length, bar is in Taiwanese, 1 bar = 0.01MM, silk is in Hong Kong language, 1 wire = 0.01MM, so 1 bar = 1 wire.

　　 17. What is the pillow position?

　　 Shell plastic parts are often opened with notches on the edges, which are used to install various accessories. The pillow-shaped part formed here is called the pillow position.

　　 18. What is a crater?

　　 The shape of the reduced rubber part at the bottom of the BOOS column reflected on the mold after the eruption is called the mold crater.

　　 19. What is huh?

　　He refers to Mo Ren, a idiom in Hong Kong.

　　 20, what is a tiger's mouth?

　　 Laohukou is also called: tube position, that is, the part used to limit the position.

　　 21. 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 bone position?

　　 The tendons on the product are called: bone position

　　 24. What is column position?

　　 The BOSS column on the product is called: column position.

　　 25. What is virtual position?

　　 The gap on the mold is called: virtual position.

　　 26. What is a deduction?

　　The hook used to connect the product is called: buckle.

　　 27. What is a fire pattern?

The pattern left after 　　 EDM is called the fire pattern.

　　 28, what PL noodles?

　　PL surface, also known as: parting surface, slap ramen, refers to the part where the front mold and the back mold contact when the mold is closed.

　　29. What is a computer gong?

　　 CNC milling machine and machining center

　　 30. What is copper work?

　　 EDM usually uses easy-to-process copper materials as discharge electrodes, which are called copper workers, or electrodes. Copper workers are generally divided into rough workers, rough workers, young workers, and young workers, also called fine workers.

　　31. What is the usual spark level?

　　 During the discharge process, the discharge gap between the copper and steel is called the spark level. The rough spark level is generally 10 to 50, and the young spark level is generally 5 to 15.

　　 32. What is the material level?

　　 The avoidance of plastic products is also called thick.

　　 33. What is the original stay?

　　 The original body stay is relative to the cutting insert. The original body stay refers to a whole piece of steel as a processing blank, which is processed together during processing.

　　 34. What is the weld mark?

　　 The line formed when two strands of plastic meet is called a weld line.

　　35, what is jet stream?

　　 After the plastic enters the cavity from the plastic inlet, it forms a curved and folded snake-like flow mark called a jet.

　　 36. What is LKM?

　　 LKM refers to the Longji mold. Commonly used molds are: LKM, Fudeba, Mingli, Huansheng, Changhui, Desheng.

　　37. What does DME mean and what does HASCO mean?

　　 DME and LKM are the standards of standard parts, DME is made in the United States, and HASCO is made in Europe.

　　 38. What is an inverted button?

　　The parts of the product that cannot be directly demolded from the front and rear molds become undercuts.

　　 39. What is foolproof?

Fool-proof is a idiom, which is to prevent a very simple mistake and prevent you from being in a daze! For example, if an insert is made of the same size hanging platform on the heaven and earth side, it is very likely that the heaven and earth side will be installed upside down during on-site assembly. , But he made a hanging platform on the side of the insert. At this time, if the heaven and earth side is reversed, it will not fit in. It is impossible to install it wrong. This kind of action to prevent the occurrence of a daze and cause errors becomes a daze.

　　40. What is a beer machine?

　　 beer machine is a local idiom, which is what we often call injection molding machine, molding machine.

　　 41. What is the stop mouth?

　　Zhukou is the art line of clamping mouth, also known as the ugly line.

　　42. What is a flying model?

　　 Flying mold means matching mold or standard mold.

　　 43. What is a light knife?

　　 The action of CNC finishing is called light knife, that is, it is processed in place on the basis of roughing.

　　 44, what is frame opening?

　　The action of processing the position of the mold core on the mold base is called frame opening.

　　 45. What is sun-charging?

　　Banzi is a processed font that is placed on the film and then added to the font.

　　 46, what is anti-huh?

　　 The method of inverting the front and rear mold material positions under normal conditions to open the mold is called reverse.

　　47, what is floating?

　　The part where there is an undercut is the ejection method of using small inserts to eject it is called floating.

　　48. What is a pre-eating model?

　　 When the mold is opened, the product stays in the front mold is called the front mold.

　　49, what is Dingbai?

　　 The mold force required for ejection is relatively large, and the ejector pin is not strong enough, causing the product to be partially ejected. From the front of the product, there is an obvious white as the top white, which is also called the top nozzle.

　　50, what is baking?

　　The mark left by the entry point on the exterior surface of the point during diving is called the bake mark.

　　51, what is a yard?

The 　　 yard is a clamping tool, a kind of cushion block with a triangular inclined surface opening slot.

　　52, what is overcutting?

　　 Overcutting refers to excessive cutting, that is, the parts that do not need to be processed are also processed when processing the workpiece. Overcutting is not good.

　　53. What is the school cup?

　　The front mold pops out of the mold opening position.

　　54. What is Yata?

　　Tapping. Tapping thread is called Yata, a Cantonese idiom.

　　55. When do I need to make a two-color mold?

　　 When a product contains two different materials or the same material with different colors, design a two-color mold for molding.

　　56. What is the mold design process of the factory?

Customers provide product drawings→analyze products→confirm plastic varieties→confirm mold material→transfer engineering drawings→multiply and shrink to make a mirror image→improve assembly drawing→order mold base→order mold core material→draft→3D parting→determine runner /Gating method→Refer to the ranking drawing for structural design→dismantle inserts→correct 3D→project drawing "including: mold core/insert/mold blank/parts"→make BOM table→proof and review

　　 57. How many ways are there for demoulding?

　　 smooth and forced

　　58. What are the ways to feed glue?

　　Direct glue feeding → overlapping glue feeding → side glue → ring feeding glue → sheet feeding → latent type → dispensing glue → horn feeding → fan feeding.

　　59. What are the forms of the runner?

　　There are circular runners→semi-circular runners→T-shaped runners→hexagonal runners.

　　60. Standing manuals and books for mold designers

　　 Steel books, plastic books, mold standard parts books.

　　61. What is the function of the spring?

　　 Resilience occurs when external use appears

　　 62. Why is the mold drafted?

　　 Prevent the product from being strained when it is demolded.

　　63. The role of the screw and the determination of the mating length

　　 is mainly used for tightening and fixing, and the mating length is generally 1.5 to 2 times the diameter of the screw.

　　 64. What is the general slope of the slider, and what is the general slope of the oblique guide column?