Injection molding of plastic injection molds Please follow the following standards

- Jun 27, 2017-

Molding product appearance, size, with

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    1. product surface does not allow defects: lack of material, charred, top white, white line, Phi peak, blistering, pull white (or crack, pull off), baking, wrinkles. The

 

    2. Fusing marks: the general round perforation weld length of not more than 5mm, shaped perforation weld length less than 15mm, weld line strength and through functional safety testing. The

 

    3. Shrink: the appearance of the surface is not allowed to shrink, not obvious to allow a slight shrink (feel no dent).

 

    4. General small product flatness is less than 0.3mm, there are assembly requirements to ensure that the assembly requirements.

 

    5. Appearance can not have a clear pattern, expected flowers, the product generally can not have bubbles. The

 

    6. The geometry of the product, the size of the size of the accuracy should be consistent with the formal open model drawings (or 3D files) requirements, product tolerances according to the principle of tolerance, shaft size tolerance for the negative tolerance, hole size tolerance is positive tolerance, Required as required. The

 

    7. Product wall thickness: product wall thickness generally requires the average wall thickness, non-average wall thickness should meet the requirements of the drawings, the tolerance according to the mold characteristics should be -0.1mm. The

 

    8. Product with: shell shell with: the surface is less than 0.1mm dislocation, can not scratch the phenomenon, with the requirements of the hole, shaft, surface to ensure that with the interval and use requirements.

 

Injection mold

 

Injection mold

 

    two

 

    Mold appearance

 

    1. Mold nameplate complete, clear characters, neatly arranged.

 

    2. The nameplate shall be secured to the mold foot near the template and the reference angle. The nameplate is fixed and reliable.

 

    3. Cooling nozzle should be used plastic block inserted mouth, the customer otherwise required by the request.

 

    4. The cooling nozzle should not extend out of the mold surface

 

    5. Cooling nozzle to be processed counterbore, counterbore diameter of 25mm, 30mm, 35mm three specifications, hole chamfer, chamfer should be consistent. The

 

    6. Cooling nozzle should be out of the mark.

 

    7. Mark the English characters and numbers should be greater than 5/6, the position in the faucet below 10mm, writing should be clear, beautiful, neat, evenly spaced.

 

    8. Mold parts should not affect the mold hoisting and storage. Installed below the exposed cylinder, faucet, pre-resetting mechanism, etc., should support the leg protection.

 

    9. Installation of the support legs The application screws are fixed to the mold frame through the support legs. The long support legs can be fastened to the mold frame by machining the external thread.

 

    10. Die hole size should meet the specified requirements of the injection molding machine, in addition to small mold, can not only use a center out.

 

    11. positioning ring should be fixed and reliable, circle diameter of 100mm, 250mm two, positioning ring higher than the bottom 10 ~ 20mm. Except as otherwise required by the customer.

 

    12. Mold size should meet the requirements of the specified injection molding machine.

 

    13. Install the direction of the required mold should be in the front or rear template with arrows indicate the installation direction, arrows should be next to the "UP" words, arrows and text are yellow, the word height of 50mm.

 

    14. Mold surface should not have pits, rust, excess rings, access to water vapor, oil holes, etc. and the appearance of the defects.

 

    15. Mold should be easy to lift, transport, lifting can not be removed when the mold parts, rings and faucets, cylinders, pre-resetting rods and other interference.

 

    three

 

    Mold material and hardness

 

    1. Mold mold frame should be used to meet the standard standard mold.

 

    2. Mold forming parts and pouring system (core, moving die insert, movable insert, shunt cone, putter, sprue sets) material with a performance higher than 40Cr above the material.

 

    3. Molded on the mold easy to corrode the plastic, the molding parts should be made of corrosion-resistant materials, or its molding surface should take anti-corrosion measures.

 

    4. Mold forming parts hardness should not be less than 50HRC, or surface hardening hardness should be higher than 600HV.

 

    four

 

    Ejection, reset, pull the ferrule, pick up

 

    1. Top should be smooth, no stuck, no abnormal sound.

 

    2. The sloping surface should be polished and the oblique top surface is lower than the core surface.

 

    3. Sliding parts should be opened sump, the surface required nitriding treatment, after treatment, the surface hardness of HV700 or more.

 

    4. All mandrels should have a stop position, and each mandrel should be numbered.

 

    5. Extend distance application limit block for limit.

 

    6. The return spring should be used standard parts, spring ends must not be polished, cut off.

 

    7. The slider, the core should have the stroke limit, the small slider with the spring limit, the spring inconvenient to install the wave screw; cylinder core must have a trip switch.

 

    8. Slider core generally use inclined guide column, oblique guide column angle should be smaller than the slider locking surface angle 2 ° ~ 3 °. Slider stroke should be too long should be used cylinder pumping.

 

    9. Cylinder cylinder core forming part of the end is covered, the cylinder should be added self-locking mechanism.

 

    10. Slider width of more than 150mm under the large slider should wear plate, wear plate material should be used T8A, after heat treatment hardness HRC50 ~ 55, wear plate than the large surface higher than 0.05 ~ 0.1mm, and open Oil tank.

 

    11. The mandrel should not be moved up and down.

 

    12. bar on the barb, the direction of the barbs should be consistent, barbs easy to remove from the product.

 

    13. The contact clearance between the plunger hole and the mandrel, the length of the sealant and the surface roughness of the mandrel hole shall be in accordance with the relevant enterprise standard.

 

    14. Products should be conducive to the operator removed.

 

    15. Products are easy to follow when the top of the ramp to go, the top of the bar should be added or eutraged.

 

    16. Fixed in the top of the rod on the top block should be solid and reliable, around the non-forming part of the processing should be 3 ° ~ 5 ° slope, the lower part should be chamfered.

 

    17. There should be no iron debris in the oil passage hole in the mold frame.

 

    18. Return rod end smooth, no spot welding. There is no gasket at the bottom of the embryo.

 

    19. Three plate mold gate plate sliding guide smooth, easy to open the gate plate.

 

    20. Three-plate limit rod should be arranged in the direction of the installation of the mold on both sides, or in the mold outside the pull plate, to prevent the limit rod and operator interference.

 

    21. Oil circuit should be smooth, hydraulic pressure reset should be in place.

 

    22. At the bottom of the guide sleeve, open the exhaust port.

 

    23. Positioning pin installation can not have a gap.

 

    Fives

 

    Cooling, heating system

 

    1. The cooling or heating system should be fully open.

 

    2. Seal should be reliable, the system can not leak at 0.5MPa pressure, easy to repair.

 

    3. The size and shape of the sealing groove provided on the mold frame shall comply with the relevant standard requirements.

 

    4. Seal ring should be coated with butter, placed after the mold surface.

 

    5. Water, oil flow channel septum should be used is not susceptible to corrosion of the material.

 

    6. Before and after the mold should be used to focus on water, the way.

 

    six

 

    Gating system

 

    1. The gate setting should not affect the appearance of the product to meet the product assembly.

 

    2. Flow section, length should be designed to ensure the quality of the formation under the premise of minimizing the process to reduce the cross-sectional area to shorten the filling and cooling time, while the loss of plastic system should be the least.

 

    3. The three-plate mold runner shall have a trapezoidal or semicircular cross section at the back of the front template.

 

    4. Three plate mold in the gate plate with broken material, the inlet diameter of the runner should be less than 3mm, the ball at the concave gate of a 3mm deep step.

 

    5. Ball head pull rod should be reliable and can be pressed under the positioning ring, headless screw can be fixed, you can press the pressure plate.

 

    6. Gate, runner should be the size of the drawings with the machine should be processed, not allowed to manually throw grinding machine processing.

 

    7. Point gate gate should be required according to specifications.

 

    8. The front end of the shunt should have an extended part as a cold material.

 

    9. Pull rod Z-shaped buckle should be a smooth transition.

 

    10. The shunt on the parting surface should be round and the front and rear molds can not be dislocated.

 

    11. The latent gates on the top rod should have no surface shrinkage.

 

    12. Transparent products cold material hole diameter, depth should meet the design standards.

 

    13. easy to remove the material, the appearance of products without gate traces, the product assembly without residue material.

 

    14. hook hook potential gate, two parts of the insert should be nitriding, the surface hardness to HV700.

 

    Seven

 

    Hot runner system

 

    1. Hot runner wiring layout should be reasonable, easy maintenance, wiring number should be one by one correspondence.

 

    2. The hot runner should be tested for safety, with an insulation resistance greater than 2 MW.

 

    3. Temperature control cabinet and hot nozzle, hot runner should be used standard parts.

 

    4. The main mouth of the thread with the hot runner connection, the bottom plane contact seal.

 

    5. The hot runner is in good contact with the heating plate or heating rod. The heating plate is fixed with screws or studs.

 

    6. J-type thermocouple should be used and matched with the temperature control table.

 

    7. Each group of heating elements should be thermocouple control, thermocouple location is reasonable.

 

    8. The nozzle should meet the design requirements.

 

    9. The hot runner should be reliably positioned with at least two locating pins or screwed.

 

    10. There should be a thermal pad between the hot runner and the template.

 

    11. Temperature control table set temperature and actual display temperature error should be less than ± 5 ° C, and temperature control sensitive.

 

    12. Cavity and nozzle mounting holes should pass through.

 

    13. Hot runner connections should be tied and covered with platens.

 

    14. There are two identical specifications of the socket, should be clearly marked.

 

    15. Control lines should be sheathed, without damage.

 

    16. Temperature control cabinet structure is reliable, the screw is not loose.

 

    17. The socket is mounted on a board and can not exceed the maximum size of the template.

 

    18. The wires are not allowed to be exposed to the outside of the mold.

 

    19. Hot runner or template All contacts with the wire should be rounded transition.

 

    20. Before the template assembly, all lines are not short-circuit phenomenon.

 

    21. All wiring should be properly connected, insulation performance is good.

 

    22. After the template is clamped, all lines are checked again using a multimeter.

 

    Eight

 

    Forming part, parting surface, exhaust slot

 

    1. Before and after the mold surface should not be uneven, pits, rust and other effects of the appearance of other defects.

 

    2. Inlaid with the mold frame, around the fillet should be less than 1mm gap.

 

    3. Partial surface to keep clean, clean, no hand wheel grinding to avoid empty, sealing part of no depression.

 

    4. Exhaust groove depth should be less than the overflow value of plastic.

 

    5. Embedded research and development should be in place, placed smoothly, reliable positioning.

 

    6. Inlay, inlay, etc. should be reliable positioning fixed, round pieces have stop, inserts below the copper plate, iron.

 

    7. The end of the mandrel is the same as the core.

 

    8. Before and after the mold part of the no upside down, chamfering and other defects.

 

    9. Bend out should be smooth.

 

    10. Multi-cavity mold products, symmetrical left and right, should indicate L or R, the customer position and size requirements, should meet customer requirements, generally do not affect the appearance and assembly of the place, the font size of 1/8 The

 

    11. Mold-type locking surface research and development should be in place, more than 75% of the area encountered.

 

    12. The mandrel should be placed closer to the side wall and to the side of the rib and boss, and a larger mandrel should be used.

 

    13. For the same pieces, please specify numbers 1, 2, 3 and so on.

 

    14. The contact surface, insert the surface, sub-surface should be developed in place.

 

    15. Partial sealant parts should meet the design standards. Medium mold 10 ~ 20mm, large mold 30 ~ 50mm, the rest of the machine processing to avoid air.

 

    16. Dermatoglyphics and sandblasting should meet customer requirements evenly.

 

    17. The appearance of the required products, products on the screws should be anti-shrink measures.

 

    18. The depth of more than 20mm screw column should use pipe jacking.

 

    19. Product wall thickness should be uniform, deviation control in ± 0.15mm below.

 

    20. The width of the ribs shall be less than sixty percent of the wall thickness of the appearance

 

    21. The sloping roof, the slider on the core should have a reliable fixed way.

 

    22. The former mold insert after the mold or after the mold into the front mold, around the slope should be locked and machining to avoid shelter.

 

    nine

 

    Injection molding production process

 

    1. Mold in the normal injection molding process conditions, should have the stability of injection molding and process parameters to adjust the repeatability.

 

    2. Injection molding injection molding pressure, the general should be less than the maximum injection pressure of 85% of the maximum injection pressure.

 

    3. The injection speed at the time of injection molding of the mold is not less than 10% of the rated maximum injection speed or 90% of the rated maximum injection speed.

 

    4. Mold injection molding pressure when the pressure should generally be less than the actual maximum injection pressure of 85%.

 

    5. Mold injection molding production clamping force, should be less than 90% of the rated model clamping force.

 

    6. Injection molding process, the product and the outlet material to be easy to remove, the time is generally not more than 2 seconds).

 

    7. Die with inserts products, easy to install in the production of inserts, inserts fixed to be reliable.

 

    ten

 

    Packing and shipping

 

    1. Mold cavity should be cleaned clean spray rust oil.

 

    2. Slip parts should be lubricated.

 

    3. Grease sealing is applied to the inlet of the sprue.

 

    4. Mold should be installed lock mold, specifications meet the design requirements.

 

    5. Spare parts spare parts should be complete, with a list and supplier name

 

    6. Mold water, liquid, gas, electricity import and export should be taken to seal the closure of foreign matter to enter;

 

    7. The outer surface of the mold is sprayed and the customer has the required requirements.

 

    8. Mold should be used moisture, water, to prevent bump packaging, the customer has the required press


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