1. The craftsman compiles the craft card

When compiling the process card, the craftsman should indicate in detail the reserved amount for processing, the orientation of the reserved amount, roughness requirements and precautions in the process card.

The principle of processing process card writing: on the premise of ensuring accuracy and quality, give priority to the use of equipment with high processing efficiency. The processing efficiency of milling machine, CNC, and grinding machine is faster than that of wire cutting and electric pulse, especially the processing efficiency of electric pulse is the slowest. The size on the drawing cannot be changed at will (only the technician can change it).

2. The principle of reserved amount for processing

For workpieces that require heat treatment, add 0.25mm to the grinding machine allowance on one side of the shape preparation size before heat treatment, and reserve 0.2mm on one side for the parts that require CNC rough machining for mold cores and inserts. Leave a margin of 0.3-0.5mm. For workpieces that need to be processed by a grinding machine after wire cutting, 0.05mm is reserved for one side of the forming part, and a grinding margin of 0.1mm is reserved for one side of the rough shape; CNC finishing, mirror surface after electric pulse Polishing, leaving a polishing allowance of 0.03mm on one side.

3. Machining accuracy requirements

The manufacturing accuracy of the mold size should be in the range of 0.005-0.02mm; the verticality should be in the range of 0.01-0.02mm; the coaxiality should be in the range of 0.01-0.03mm; the upper and lower planes of the moving and fixed mold parting surfaces The parallelism required in the range of 0.01 ~ 0.03mm.

After the mold is closed, the gap between the parting surfaces is smaller than the overflow value of the molded plastic. The parallelism of the matching surfaces of the rest of the formwork is required to be within the range of 0.01-0.02mm; the matching accuracy of the fixed part is generally selected within the range of 0.01-0.02mm; if the small core has no requirements for insertion or has little effect on the size, it is preferable to use 0.01-0.02mm on both sides The gap fit; the fit accuracy of the sliding part generally chooses three types: H7/e6, H7/f7, and H7/g6.

Note: If there is an insert on the mirror surface that is attached to a step, the fit should not be too tight. Otherwise, when the insert is knocked back from the front, the tool used for knocking will easily damage the mirror surface. If it does not affect the product size, it is preferable to use 0.01~ on both sides. 0.02mm clearance fit.

4. The principle of CNC electrode removal

The core of the mold cavity should first remove the appearance main electrode, then remove the other main electrodes, and finally remove the partial electrodes; the appearance electrode of the fixed mold should consider the overall processing, and use wire cutting to clear the corners for the place where the CNC can't clear the corners, so that the mold can be fixed The appearance surface is complete without joint marks; the ribs, ribs, and columns with the same depth of the movable mold can be processed together as much as possible on one electrode; the deeper ribs are used as inserts, and the electrode side punching is required separately. In order to prevent carbon deposition during electric pulses, try not to wire-cut the corners after CNC milling the movable mold electrode, if necessary, disassemble the electrode or use wire cutting directly, the ribs and ribs of the movable mold or the pillars If the interval exceeds 35mm, it should be done separately to save copper material.

The rough machining spark position of large electrode is 0.3mm on one side, the finishing spark position is 0.15mm on one side; the general electrode rough machining spark position is 0.2mm on one side, and the finishing spark position is 0.1mm on one side; the small electrode rough machining spark position 0.15mm on one side, and 0.07mm on one side for finishing sparks.

5. CNC machining principles

The part of the mold core and insert that needs to be roughed by CNC, with a margin of 0.2mm on one side, and the workpiece that needs to be finished by CNC after heat treatment, if the appearance of the product allows, the core of the mold cavity that can be finished by CNC, CNC is preferred For processing, if the electrode cannot be processed in place, use electric pulse processing.

6. Dynamic and static mold core processing technology

1) Prepare materials.

2) Milling machine processing: drilling water hole (the distance between the deepest water hole plug and the horizontal water hole is 3-4mm), threading hole, drilling and tapping screw hole, drilling and reaming pinhole, mold number, reference angle , hanging table to give way.

3) CNC machining: rough machining.

4) Heat treatment processing: specify the hardness requirements.

5) Grinding machine processing: grind the hexagonal square, and the shape is ground according to the size of the matching frame (if the mold core is one piece, the shape size is minus 0.03mm-0.05mm than the drawing size, if the mold core is two pieces, the two mold cores are combined The sum of the external dimensions in the rising direction is minus 0.03mm-0.05mm) ⊥ 0.01, ∥ 0.01 than the drawing size, and the part that can be formed by the grinder must be ground and formed.

6) If you need CNC finishing mold core, arrange CNC finishing, if the cavity has fonts and mold numbers, lettering processing is required.

7) Wire cutting processing: middle wire processing insert hole, inclined top hole, ejector pin hole, nozzle hole, etc.

8) Electrical discharge machining: process according to drawings and pulse instructions.

9) Polishing process: Write the roughness and requirements of polishing on the process flow card, and mark the polished area on the workpiece with a marker pen. If there is a mirror surface requirement, if the cycle is too late, rough polishing can be performed first and then fine polishing.

10) Assembly.

11) Trial mold.

7. Main body insert processing technology

1) Prepare materials: the craftsman defines whether it is a single piece of processing or multiple pieces of processing according to the size and shape of the workpiece. If multiple pieces are processed together, the craftsman needs to map out the processing arrangement of the workpiece.

2) Milling machine processing: the fitter performs processing according to the workpiece drawing or the arrangement drawing combined with the craftsman, drilling the water delivery hole (the deepest water delivery hole plug is 3-4mm away from the horizontal water delivery hole), threading hole, drilling, Tapping screw holes, drilling and reaming pinholes, roughing the forming part, numbering the mold, and giving way to the hanging table.

3) CNC processing: If CNC rough machining is required, arrange CNC rough machining.

4) Heat treatment processing: specify the hardness requirements.

5) Grinding machine processing: Grinding the hexagonal square, the part that can be formed by the grinding machine must be ground and formed.

6) If the workpiece needs CNC finishing, arrange CNC finishing. If the insert has fonts and model numbers, it needs to be engraved.

7) Wire cutting processing: middle wire processing insert hole, inclined top hole, thimble hole, etc.

8) Electrical discharge machining: process according to drawings and pulse instructions.

9) Polishing process: Write the roughness and requirements of polishing on the process flow card, mark the polished area on the workpiece with a marker pen, if there is a mirror surface requirement, if the cycle is too late, rough polishing can be performed first and then fine polishing.

10) Assembly.

11) Trial mold.

8. Special-shaped insert processing technology

Process 1:

1) Wire cutting processing: cut the shape and size of the middle wire cutting (A/B view), pull the sheet, leave a margin for the thickness of the grinder, and roughen the forming part.

2) Grinding machine processing: grinding thickness, slope, forming.

3) Electrical discharge machining.

4) Polishing.

Process 2:

1) Wire cutting processing: cut the shape of the middle wire, the hole of the insert, the hole of the thimble, the size is cut accurately (C view), the hanging table and the forming part are roughened.

2) Grinding machine processing: grinding height, hanging table, slope, forming.

3) Electrical discharge machining.

4) Polishing.

9. Simple insert processing technology

1) Wire cutting processing: fast wire cutting shape margin grinder (A/B view), pull sheet, thickness margin grinder.

2) Grinding the external dimensions, grinding the hanger, slope, forming.

3) Electrical discharge machining.

4) Polishing.

10. Round insert processing technology

1) Centerless grinding: the external dimension is ground.

2) Grinding machine processing: clear corners at the hanging table.

3) Wire cutting processing: fast wire cutting length (leave 0.1mm grinder margin on one side), cutting pinholes and vent holes.

4) Grinding machine processing: grinding length and forming.

11. Inclined top processing technology

1) Wire cutting processing: medium wire cutting shape, the head is grinded with a margin for the inserting surface, the rest of the dimensions are ground, the thickness of the pull piece is margined, and the I-shaped groove is roughed and the margin is grinded.

2) Grinding machine processing: grinding thickness, I-shaped groove.

3) Assembly.

4) Pulse.

5) Polishing.

6) Milling machine oil groove.

12. Processing technology of inclined top seat

1) Fitter’s spare material: reserve 1.5 mm on both sides of the height dimension, 0.5 mm on both sides of the width direction, and 5 mm on both sides of the length direction to facilitate wire cutting processing and clamping.

2) Milling machine processing: drilling and tapping screw holes.

3) Heat treatment processing.

4) Grinding machine processing: Grinding the hexagonal square, and grinding the width dimension accurately.

5) Wire-cut fast wire processing I-shaped slots, pull tabs, thickness allowance grinding machine, the height dimension is 1.2 mm.

6) Grinding machine processing: The overall size of the grinding machine is matched with the thimble plate, and the height is 1mm.

13. Processing technology of inclined top guide block

1) Wire cutting processing: fast wire cutting shape, reserved for grinding machine.

2) Grinding machine processing: grinding the hexagonal square, and grinding the external dimensions accurately.

3) Milling machine processing: threading holes, screw holes.

4) Wire cutting processing: fast wire cutting inclined top guide hole.

14. Processing technology of slider seat

1) Prepare materials.

2) Grinding machine processing: grinding the hexagonal square, and grinding the external dimensions accurately.

3) Milling machine processing: drilling thread holes, drilling and tapping screw holes.

4) Wire cutting processing: fast wire processing of inclined guide post holes.

5) CNC finishing: the size of the forming part is milled accurately.

15. Briquetting process

1) Prepare materials.

2) Milling machine processing: drill screw holes, roughen the forming part (0.3-0.5 reserved for one side, grinder).

3) Grinding machine processing: Grinding the hexagonal square, grinding the shape and size, and forming.

16. Processing technology of locking block

1) Prepare materials.

2) Grinding machine processing: grinding the hexagonal square, and grinding the external dimensions accurately.

3) Wire cutting processing; fast wire forming.

4) Milling machine processing: drilling and tapping screw holes.

17. Machining principle of ejector pin hole

Milling machine drilling and reaming are used for drilling and reaming of ejector holes above Φ3 (including Φ3, Φ4, Φ5, and Φ6), wire cutting is used for holes below Φ3 or non-standard ejector holes, and the bottom is avoided.

18. Principles of threading hole processing

When various holes need to be processed by wire cutting, when the inner wall circumference is larger than Φ3 (including Φ3), the wire holes must be drilled.

19. Processing of trademarks and molds that require mirror polishing

1) There is a margin at the trademark after CNC precision milling of the mold core.

2) Wire cutting medium wire processing: trademark insert hole.

3) Electrical discharge machining: the depth of the hanging table is accurate.

4) Equipped with trademark core and installation fixture.

5) The residual pulse at the trademark is connected to level.

6) Polishing.

20. Formwork processing technology

1) Milling machine processing: inner frame chamfering, drilling screw holes, ejector pin holes, waterway holes, sprue cup via holes, inclined top hole via holes.

2) CNC processing: Milling gate cup sink hole, inclined top seat hole, guide block hole, row slot, hot runner mold A plate needs CNC processing, mold foot lettering processing.

21. Post-molding process of the mounting frame with grid-like ribs

The processing of the ribs of the mold behind this type of mounting frame is based on different mold types, and different processing techniques are selected.

1) For a type of mold, we directly use the integral electrode to ensure the uniformity of the product.

2) When selecting the processing technology of non-class molds, it can be allocated according to the actual processing volume. The electrode can be split or integral. If the rib is a through groove, the wire can be cut first, and then the grinder can be fine-tuned.

22. Workpieces that require wire cutting fixtures or electrodes, and batch pulses

For some workpieces (such as: multi-functional two-plug jack cores) wire cutting fixtures or electrodes are required, and the processing flow of workpieces with batch pulses is as follows:

1) CNC output layout.

2) The wire cutting drawing is processed according to the size of the fixture or electrode.

3) After the wire cutting process is completed, if the electrode needs CNC processing, hand over the electrode to the CNC, and hand over the fixture to the fitter.

4) CNC machining electrodes, and a discharge diagram.

5) Pulse processing.

6) Polishing.

23. Calculation of supporting column height

The height of the support column of the formwork below 3030 is 0.08-0.1mm higher than the mold foot, 0.1mm higher than 3030, 0.1-0.12mm higher than 3535, and 0.12-0.15mm higher than 3535.

24. Thimble processing technology

Φ2 and above thimble cutting machine cuts the length and leaves allowance for the grinding machine, the grinding machine processing length size is ground (the fitter processes it himself); Φ2 and below the thimble wire cutting processing size is accurate. The flat thimble and the cylinder are cut by wire cutting and the length is left to the margin grinding machine; the grinding machine is processed, and the length and size are ground accurately.