1. Transfer product's 3D drawing file to a 2D file. Sections should be made at undercuts or locations with mechanical features, paying attention to scale (1:1 ratio).
2. Apply shrinkage and mirror images to product drawing transferred to 2D file. Note: After completing these two steps, it is essential to check product. You can measure same location on product before and after shrinkage to verify that shrinkage was applied correctly.
3. Before arranging assembly, determine finished product reference line. This means locating easily accessible features on product, such as bosses or large flat surfaces, along X, Y, and Z axes. Feature should be located as close to center of finished product as possible. If upper and lower covers are mating, reference point should be same. Finished product reference line should be an integer relative to mold center.
4. Arrange mold core according to finished product reference line.
Steps and Key Points:
a. Delete dashed lines on finished product.
b. If side view is a cross-section, replace solid lines in side view with dashed lines, leaving only cross-sections as solid lines.
c. Identify parting surfaces of finished product, focusing on main parting surface, bevel pin, and slider parting surface. Insertion and support holes on parting surfaces should also be indicated.
d. Clearly indicate where mold core is removed from mold. In front view, indicate entry boundary with a yellow line, and also indicate countersunk head. Avoid thin metal between inserts; generally, gap should not be less than 1mm. (Parts of mold core that require removal are generally difficult to machine, deep ribs, and bosses.)
5. Arrange ejector pins, water lines, and finally, mold core screws. Ensure that three elements do not interfere with each other, with a minimum spacing of 3mm. This should also be considered when removing and inserting mold. Following are key points for arrangement of ejectors, water channels, and screws:
a. Ejectors should be placed where finished product is difficult to remove from mold, such as along edges, ribs, and deep within plastic. Ejectors should be as large as possible to increase strength. Distance between ejector and finished product should be at least 0.6-1mm to avoid thin metal.
b. Purpose of water channel is to quickly remove mold heat to achieve effective cooling. Straight water channels are most effective.
C. Four screws are generally placed in mold core, and their placement should be as symmetrical as possible.
6. When arranging mold core, consider strength. Distance between product edge and mold core edge should be at least 20mm. Distance between mold core edge and mold frame edge should be determined by size of mold: at least 50mm for large molds and 30-50mm for small molds (under 350mm on the top and bottom sides are considered small molds). Special requirements will be addressed individually.

1. Finished products should be positioned in inner mold for optimal results, taking into account position of watermark and parting surface. Position should be proportional to size and depth of finished product.
2. Distance between finished product and edge of finished frame:
A) Small finished products: Distance between 25mm and 30mm, 15mm to 20mm between finished products. If inserts are present, plastic material should be approximately 25mm. If there are runners between finished products, spacing should be at least 15mm.
B) Large finished products: Distance from edge should be 35mm to 50mm, with a minimum of 35mm for inserts. If multiple products are produced from a single steel part, spacing should be approximately 12-15mm. For finished products over 200mm in length and 150mm in width, distance from edge should be at least 35mm.
3. Principles for selecting a base for finished product positioning:
A) Prioritize areas with distinct features (such as pillars, cavities caused by collisions, and bone centers).
B) When selecting a PRO/E 3D datum, specify CSO, CSI, or DTM name.
C) For finished products with unusual shapes that make it difficult to determine datum, consult with CAM department before determining datum.
D) Datum of finished product and center of mold base must be integers, and a box should be placed around number when indicating dimension to distinguish it.
4. Principles for determining X and Y coordinates of inner mold frame during alignment: If length and width of inner mold frame differ significantly, the longer dimension should be used as X-axis when aligning mold base to align with factory machine tool processing direction and reduce risk of damage.

 

1. Use standard mold bases (LKM or Hongfeng) whenever possible.
A) When converting from an I-shaped mold to a straight mold, do not move square iron; instead, drill mold holes directly on square iron.
B) Non-standard mold bases must be approved by supervisor and indicated on alignment diagram.
2. For CH and CT mold bases, create a code mold pit with a height and width of approximately 25-35mm, with length determined by mold base height.
3. Diameter of slingshot hole should be between 1-2mm larger than slingshot diameter, and should be recessed into B plate at least 20-30mm deep.
4. When submitting mold base processing drawings, mold base supplier should process nozzle hole (flange), spring holes, recessed recesses for square auxiliary device mounting, or handle edge nail holes. Large mold bases (800x800) require support holes (including bottom screw holes), beveled clearance holes, beveled bronze inserts, beveled color inserts, slides, slide pressure plates, water transport, and water transport buckets. Fine-sprue mold bases also require sprue tie rods, slingshot glue holes, glue holes, and plug screw holes. Before submitting mold base processing drawings, please consult factory for requirements and determine required processing items based on factory's actual workload.
5. For large sprue molds with a diameter of 2730 mm or larger, thickness of plate A should be depth of fine frame plus 25-35 mm, and thickness of plate B should be depth of fine frame plus 50-70 mm. For molds with a diameter of 2525 mm or smaller, thickness of plate A should be approximately 25-30 mm for frame depth plus 25-30 mm, and plate B should be 40-50 mm.
6. For fine sprue molds, thickness of plate A should be 30-40 mm for frame depth plus 30-40 mm, and thickness of plate B should be 50-60 mm for frame depth plus 50-60 mm. (For specifications of large and fine sprue molds, please refer to LK mold materials.)

1. Cutting Principles:
A) For inserts requiring fine grinding in new plastic housings, cut size = actual size + 3-5mm (this size should be as consistent as possible with steel supplier's specifications);
B) Cutting size for fine grinding = actual size + allowance (e.g., +0.3/-0);
C) Cutting size for Y-CUT inserts = actual size + 5mm (one side) + 5mm (adjacent sides) + 20mm (opposite side) + 20mm (adjacent sides of opposite sides);
D) Cutting size for inserts requiring hardening = actual size + 10mm (fine grinding not included).
2. Mold steel should be ordered according to molecular weight plastic properties of finished product (including beer plastic). For example:
A) For beer PVC products, GS083H, S136, S136H, or beryllium copper can be used as inner mold material depending on pattern structure.
B) Inner mold materials for transparent beer, POM, nylon, ABS, and K-linen are GS083HS136, S136H, and other steels. (Note: Molds made of S136H, GS083H, and S136 steels should not be welded except under special circumstances. If welded, materials must be annealed and tempered.)
C) Except for beer-resistant or transparent rubber materials, inner mold materials for other finished products are P5, P20, 738, and 718 steels.

 

D) Yellow-label steel is commonly used for inner mold gate iron.
E) Runners, bolsters, and runner pressure plates are generally 738 steel (except for runners without inserts).
F) All alloy molds are made of 8407 steel (including inner mold material) for easier hardening.
G) When hardware is required for runner base or bolsters, 738 steel should be used.
3. Other Pre-production and Processing Requirements:
① Clearance between plates A and B is 0.1mm (i.e., the total height of inner mold material plastic mold is 0.1mm greater than combined depth of the A and B plates). For medium and large molds, clearance between plates A and B is 0.5mm. Backstitch height should be 0.05-0.2mm less than clearance between plates A and B (i.e., height of the stool + height of plate B + clearance height - clearance of 0.05-0.2mm - height of bottom pin plate and waste pin = backstitch length).
② Top surface of mold base (draw hole, i.e., mold hanging hole) should be marked with factory and customer numbering table. Marking should be at least 12mm thick and marking should be neat.
③ All mold openings should be pierced on four corners of plate B, forming equilateral triangles with a depth of 4-5mm and rounded or chamfered edges.
④ All water inlets and outlets on mold base must be marked with "1 IN - 1 OUT"—"2 IN - 2 OUT," etc.
⑤ Spacing and thread specifications of code mold holes are determined according to injection molding specifications.
⑥ Requirements for upper and lower mold materials and mold base are as follows:
A) Mold base and four sides of mold frame should have a 45% chamfer of approximately 1mm x 1mm.
B) Mold surfaces of A and B plates should have a 5mm rounded area on the edge of frame, 1/2" in diameter, and 0.5mm deep, according to number of inner mold materials. These areas will be marked with inner mold numbers to facilitate assembly. Plate A should be marked with numbers 1, 2, and 3, plate B should be marked with numbers 01, 02, and 03. Upper and lower mold materials should be marked with factory number (XXXX) on A and B plates. Upper mold should be numbered XXXX-1, 2, and 3, lower mold should be numbered XXXX-01, 02, and 03. Numbers must be symmetrical (i.e., upper mold is 1 and lower mold is 01 for a box). Markings on upper and lower molds are 30mm long, 8mm wide, and 0.5mm deep. New plastic shell is stamped with a 5.0mm supply mark. Inner mold numbers should be engraved or stamped as specified by customer.
C). Tolerance for upper and lower mold frames is ±0.02mm. Tolerance for upper and lower mold material is ±0.02mm. Tolerance for upper and lower mold material dimensions is ±0.02mm.
⑦ When moving mold, exterior should be clean and interior mold should be sprayed with anti-rust oil.

 

1. Knockout hole is generally placed in the center of mold. If there are multiple knockout holes, spacing between them is generally 100mm.
2. Support columns should be placed as close to center of mold as possible, close to knockout hole, and as large as possible. Care should be taken to avoid interference with ejector pins, bevel pins, and other mechanisms. Support columns are more necessary on the top and bottom sides than on the left and right sides.
3. When ejector pin is smaller than 2mm, mold requires EGP. However, there are special requirements. Position it on the top and bottom sides of mold.
4. Mold hanging hole should be placed where it will not interfere with other mechanisms. If there is interference between mold plates, they should be shifted and dimensions noted.
5. When mold's top and bottom sides exceed 350mm in length, additional ejector plate screws and STs are required, two M10 screws on each side should be tightened between lower retaining plate and mold foot.
6. If mold plates of a mold frame are both thicker than middle number listed for standard mold frame, GP should be increased by one step. If mold frame is non-standard, top and bottom sides, or the left and right sides, are elongated, GP should be increased by one step. GP calculation for a three-plate mold is: length of GP below parting surface between male and female mold plates is equal to the total length of finished material plus 30-40mm.
7. Small tie rods should be placed on the left and right sides of mold. Small tie rod stroke is calculated as the total length of slab plus 15-20mm.
8. Resin shutters in three-plate molds should be placed on the left and right sides of mold as much as possible.
9. Mold generally requires an RP spring. Calculation for spring hole is ejection distance multiplied by 2 plus 10mm. Spring length is spring hole length plus 10mm.
10. If product has an undercut, inclined pins, sliders, and other mechanisms may be required. Side view of finished product's feed point should be partially enlarged. Inclined pins and sliders should be shown as much as possible in side view.
11. Layout and annotation key points of assembly drawing: Assembly drawing should show mold in the front view. Core, core screws, ejector pins, water channels, bevel pins, sliders, runners, inlet points, injection nozzles, locating rings, knockout holes, support columns, EGPs, small tie rods, resin shutters, return pin springs, and positioning blocks. Similarly, side views should also be marked.
Assembly drawing focuses on the areas of mold frame to be processed, including mold frame's overall dimensions and dimensions of each platen, locations of hanging mold holes, GPs, RPs, EGPs, knockout holes, support columns, core dimensions, ejector plate screws, STs, small tie rods, resin shutters, injection nozzles, locating rings, and finished product's reference line.

1. Pay attention to following points during dimensioning:
a. Ensure correct scale when transferring drawings.
b. Before marking, overlay the assembly drawing to check for consistency between 2D and 3D drawings.
c. Detail magnifications should be magnified at ratios of 2, 4, 5, or 10. Generally, mark 1:1 drawing first, then mark detail magnification. Dimension lines should be exploded when marking detail magnification. Magnified area should have dimensions corresponding to magnified image for easy verification.
d. After marking a part, check that marking origin is correct.
2. Key dimensions to mark:
a. Mold core rough dimensions
b. Dimensions for mold core ejector pins, cooling channels, and screw locations. If mold core is complex, indicate this on a separate drawing.
c. Main dimensions of product on mold core and discharge depth.
d. Dimensions of male and female mold cores where gaps meet, with gap indicated after dimensions.
e. Dimensions of areas requiring EDM. Draft angle dimensions.
f. Dimensions of inclined wire-cut holes in mold core, such as bevel pins and bevel inserts.
g. Dimensions that need to be marked on mold plate include: mold frame dimensions, ejector pins, water channels, screws, nozzle holes, three-plate mold inlet runners, corresponding locations for bevel pins and sliders, positioning blocks, etc.
3. Other
a. Drawing frame should maintain a 1:1 ratio. If enlargement is required, indicate enlargement ratio.
b. Corresponding parts should be placed in same frame whenever possible. For example, core should be placed with core insert, and slider should be placed with corresponding slider parts. Mold plate should not be placed in same frame with core, insert, etc.
c. Parts should be arranged in numbered order within frame.
d. Frames should be numbered sequentially from assembly drawing to mold plate drawing to core drawing.
e. After completing a drawing, note designer, completion date, and other relevant information.
f. Create a 3D drawing based on customer's 2D product drawing. Convert completed 3D drawing to 2D and re-annotate it according to customer's 2D drawing to check for consistency. Dimensions within tolerance ranges should be indicated in different colors. Annotated drawing should be archived.

1. Check assembly drawing for mechanical interference.
2. Check mold core, template, and other parts for missing dimensions.
3. Check mating dimensions of mating parts.