Die acceptance standard
First, the appearance of the mold
1. The mold nameplate has complete contents, clear characters and neat arrangement.
2. The nameplate shall be fixed on the mold foot near the template and reference Angle. The nameplate is fixed and reliable and not easy to peel off.
3. The cooling water nozzle should be plastic block nozzle, if the customer has other requirements, according to the requirements.
4. The cooling water nozzle should not extend out of the surface of the formwork.
5. The cooling water nozzle shall be processed with countersunk holes, the diameter of which shall be 25mm, 30mm and 35mm, and the chamfering of the orifice shall be consistent.
6. Cooling water nozzle should be marked with inlet and outlet.
7. English characters and numbers should be greater than 5/6, and the position should be 10mm below the nozzle. The handwriting should be clear, beautiful, neat and evenly spaced.
8. The mold accessories shall not affect the lifting and storage of the mold. There are exposed oil cylinder, water nozzle and pre-reset mechanism under installation, which should be protected by supporting legs.
9. The supporting leg installation application screw through the supporting leg is fixed on the mold frame, too long supporting leg can be processed by car external thread column fastened on the mold frame.
10. The size of the ejection hole of the mold should meet the requirements of the specified injection molding machine. Except for small molds, only one center can be ejection.
11. The positioning ring should be fixed reliably, with diameters of 100mm and 250mm. The positioning ring should be 10-20mm higher than the bottom plate. Unless otherwise requested by the customer.
12. The mold size should meet the requirements of the specified injection molding machine.
13. For the mold with orientation requirements, the installation direction should be marked with an arrow on the front template or rear template, and the word "UP" should be beside the arrow. The arrow and the text are yellow and the height of the word is 50 mm.
14. There should be no pits, rust marks, excess lifting rings, water vapor in and out, oil holes and other defects affecting the appearance of the mold frame.
15. The mold shall be convenient for hoisting and transportation. During hoisting, mold parts shall not be removed, and the lifting ring shall not interfere with water nozzle, oil cylinder, pre-reset rod, etc.
Two, mold material and hardness
1. The standard die frame should be selected in accordance with the standard.
2. The molding parts and pouring system (core, movable and fixed mold insert, movable insert, shunt cone, push rod, gate sleeve) shall be made of materials with performance higher than 40Cr.
3. When molding the plastic which is easy to corrode the mold, the forming parts should be made of corrosion-resistant materials, or the forming surface should take anti-corrosion measures.
4. The hardness of moulded parts should not be less than 50HRC, or the hardness of surface hardening treatment should be higher than 600HV.
Three, top out, reset, pull core, take parts
1. The roof should be smooth, no stuck, no abnormal sound.
2. The inclined top surface should be polished, and the inclined top surface is lower than the core surface.
3. The sliding parts shall be provided with oil groove, and the surface shall be nitrided, and the surface hardness shall be above HV700 after treatment.
4. All push rods shall have a stop position and each push rod shall be numbered.
5. Limit the ejecting distance with a limit block.
6 return spring should be standard parts, the two ends of the spring shall not be polished, cut off.
7. Slider, core-pulling should have travel limit, small slider with spring limit, spring inconvenient installation can be used when the wave screw; Cylinder core pulling must have a travel switch.
8. The slide block core-pulling generally adopts the inclined guide column, and the Angle of the inclined guide column should be 2°~3° smaller than that of the locking surface of the slide block. If the stroke of the slider is too long, the oil cylinder should be used to pull out.
9. When the end face of the cylinder core-pulling forming part is covered, the cylinder should add a self-locking mechanism.
10. There should be a wear plate below the large slide block with a width of more than 150 mm. The wear plate material should be T8A, and the hardness of the wear plate is HRC50~55 after heat treatment.
11. Push rod should not move up and down.
12. Add barbs on the top rod, the direction of the barbs should be consistent, and the barbs are easy to remove from the products.
13. The matching gap between the ejector hole and the ejector hole, the length of the sealing section and the surface roughness of the ejector hole shall be in accordance with the standards of relevant enterprises.
14. The product should be convenient for the operator to remove.
15. When the product is pushed out, it is easy to follow the inclined push, and grooves or etching should be added on the push rod.
16. The top block fixed on the top rod should be firm and reliable. The non-formed part around should be processed with a slope of 3°~5°, and the lower periphery should be chamfered.
17. There should be no iron debris in the oil hole of the mold frame.
18. The end face of the return rod is smooth without spot welding. No gasket at bottom of embryo head, spot welding.
The guide slide of the gate plate is smooth, and the gate plate is easy to open.
20. Three-plate die limit rod should be arranged on both sides of the direction of mold installation, or on the plate outside the die frame, to prevent interference between limit rod and operator.
21. The oil airway should be smooth and the hydraulic ejecting reset should be in place.
22. An exhaust port shall be opened at the bottom of the guide sleeve.
23. Do not install positioning pins without gaps.
Cooling and heating systems
1. The cooling or heating system should be fully unblocked.
2. The seal shall be reliable, and the system shall not leak under the pressure of 0.5mpa, which is easy to repair.
3. The size and shape of the sealing groove opened on the die rack should meet the relevant standards.
4. The sealing ring should be smeared with butter when it is placed and raised above the surface of the mold frame.
5. Water and oil runner spacers should be made of materials that are not susceptible to corrosion.
6. Centralized water supply shall be adopted in front and rear molds.
Five, gating system
1. The gate setting should not affect the appearance of the product and meet the requirements of product assembly. 2. The section and length of the flow channel should be designed reasonably, and the process should be shortened as far as possible under the premise of ensuring the forming quality, and the cross-sectional area should be reduced to shorten the filling and cooling time. At the same time, the plastic loss of the pouring system should be the least.
3. The section of the sprue on the back of the front formwork shall be trapezoidal or semicircle.
4. The three plate mould has a break handle on the gate plate, the gate entrance diameter should be less than 3 mm, and the ball head is provided with a step 3 mm deep into the gate plate.
5. The ball head pulling rod should be fixed reliably, which can be pressed under the positioning ring, fixed with headless screws, or pressed with a pressure plate.
6. The gate and runner shall be processed by machine according to the size requirements of the drawing, and manual polishing machine is not allowed.
7. The sprue should be in accordance with the standard requirements.
8. There should be an extension part at the front end of the shunting channel as a cold material hole.
9. Pull rod Z inverted buckle should be smooth transition.
10. The diverting channel on the parting surface should be round, and the front and rear modules should not be misplaced.
11. The latent gate on the top bar shall have no surface shrinkage.
12. The diameter and depth of cold cavity for transparent products should meet the design standards.
13. The handle is easy to remove, the appearance of the product has no sprue marks, and the assembly of the product has no residual handle.
14. Bend hook latent gate, two parts of insert should be nitriding treatment, surface hardness up to HV700.
Hot runner system
1. The wiring layout of hot runner should be reasonable and convenient for maintenance, and the wiring numbers should correspond to each other.
2. Hot runner should be tested for safety, and the insulation resistance to ground should be greater than 2MW.
3. Temperature control cabinet and hot nozzle, hot runner should be standard parts.
4. The main orifice is connected with the hot runner by thread, and the bottom surface is sealed by contact.
5. The hot runner is in good contact with the heating plate or heating rod, and the heating plate is fixed with screws or studs with good surface bonding.
6. J thermocouple should be used, and match with the temperature control meter.
7. Each group of heating elements should be controlled by thermocouple, and the thermocouple position should be reasonably arranged.
8. Nozzle should meet the design requirements.
9. Hot runner should be reliably positioned, with at least two positioning pins, or fixed with screws.
10. There should be heat insulation pad between hot runner and template.
11. The error between the set temperature of the temperature controller and the actual display temperature should be less than ±5°C, and the temperature control is sensitive.
12. The cavity and nozzle mounting holes should be perforated.
13. Hot runner wiring should be tied up and covered with pressure plates.
14. Two sockets of the same size shall be clearly marked.
15. The control line should be sheathed without damage.
16. The structure of temperature control cabinet is reliable and the screws are not loose.
17. The socket should be installed on the electric board and should not exceed the maximum size of the template.
18. No wires should be exposed to the mold.
19. All areas of hot runner or formwork in contact with the wire shall have rounded corner transitions.
20. Before template assembly, all lines have no circuit breaker or short circuit phenomenon.
21. All wiring should be correctly connected with good insulation performance.
22. After the template is clamped, all lines should be checked again with a multimeter.
Seven, forming part, parting surface, exhaust groove
1. The front and rear die surface should not be uneven, pits, rust and other defects that affect the appearance.
2. Insert with frame, round corners should be less than 1 mm clearance.
3. The parting surface should be kept clean and tidy, without hand-held grinding wheel to avoid air, and the sealing part should not be dented.
4. The depth of the exhaust groove should be less than the overflow value of the plastic.
5. Insert should be in place, placed smoothly and positioned reliably.
6. Insert, insert core, etc. should be reliably positioned and fixed, circular parts have rotation stop, and there is no copper and iron sheet under the insert.
7. End face of ejector rod is consistent with core.
8. The front and back molding parts have no inverted, chamfering and other defects.
9. The ejecting of the tendon position should be smooth.
10. Multi-cavity mold products, left and right parts symmetrical, should indicate L or R, customers have requirements for location and size, should meet customer requirements, generally does not affect the appearance and assembly of the place, the size is 1/8.
11. The clamping surface of the formwork should be in place and more than 75% of the surface should be touched.
12. The ejector rod should be arranged near the side wall and beside the rib and boss, and a larger ejector rod should be used.
13. Serial numbers 1, 2, 3, etc. should be indicated for the same parts.
14. The collision and penetration surfaces, insertion surfaces and parting surfaces should be fitted in place.
15. The sealing part of parting surface should meet the design standard. Medium mold below 10~20mm, large mold 30~ 50mm, the rest of the machining to avoid space.
16. Skin grain and sand blasting should be uniform to meet customer requirements.
17. If the appearance of the products is required, the screws on the products should be shrinkproof measures.
18. Pipe jacking shall be used for screw columns with a depth exceeding 20 mm.
19. The wall thickness of the product should be uniform, and the deviation should be controlled below ± 0.15mm.
The width of the rib should be less than 60% of the thickness of the outer wall.
22. When the front die is inserted into the rear die or the rear die is inserted into the front die, the bevel should be locked around and processed by parallel machine to avoid air.
Eight, injection molding production process
1. Within the scope of normal injection process conditions, the mold should have the stability of injection production and repeatability of process parameters adjustment.
2. The injection pressure during injection production should generally be less than 85% of the maximum rated injection pressure of the injection molding machine.
3. The injection speed of the mold during injection production shall not be less than 10% or more than 90% of the rated maximum injection speed for three quarters of the stroke.
4. The holding pressure of the mold during injection production should generally be less than 85% of the actual maximum injection pressure.
5. The clamping force of the mold during injection production should be less than 90% of the rated clamping force of the applicable model.
6. In the process of injection molding, the product and nozzle material should be taken out easily and safely (the time is generally not more than 2 seconds each). 7. For molds with insert products, insert installation is convenient and insert fixation is reliable during production.
Ix. Packaging and transportation
1. The mold cavity should be cleaned and sprayed with anti-rust oil.
2. Sliding parts should be lubricated.
3. The feed inlet of the gate sleeve shall be blocked with grease.
4. The mold should be installed with locking plates, and the specifications meet the design requirements.
5. Spare parts and wearing parts should be complete, and attached with a list and supplier name.
6. Sealing measures should be taken to seal the inlet and outlet of water, liquid, gas and electricity of molds to prevent foreign matter from entering.
7. Spray paint on the outer surface of the mold, as required by customers.
8. The molds shall be packed with moisture-proof, waterproof and anti-knock, and shall be subject to customer requirements.
9. Mold product drawings, structural drawings, cooling and heating system drawings, hot runner drawings, spare parts and mold material supplier details, operation instructions, mold test report, factory inspection certificate, electronic documents should be complete.