ABS, powszechnie znany jako styren butadienowo-akrylonitrylowy, powstaje w wyniku kopolimeryzacji akrylonitrylo-butadieno-styrenu. Ze względu na różne proporcje trzech monomerów, ABS o różnych właściwościach i temperaturze topnienia można rozszerzyć do ABS o różnych zastosowaniach i właściwościach, such as impact grade, heat resistance grade, flame retardant grade, transparent grade, reinforced grade, electroplating grade, itp., if it is blended with other plastics or additives.
The fluidity of ABS is between PS and PC. the fluidity of ABS is related to injection temperature and pressure. The influence of injection pressure is slightly greater. W związku z tym, higher injection pressure is often used to reduce melt viscosity and improve filling performance.
1. Treatment of plastics
The water absorption rate of ABS is about 0.2% – 0.8%. For general grade ABS, bake in oven at 80-85 ℃ for 2-4 hours or in drying hopper at 80 ℃ for 1-2 hours before processing. For heat-resistant ABS with PC component, the drying temperature should be adjusted to 100 ℃, and the specific drying time can be determined by extrusion. The proportion of recycled materials should not exceed 30%, and the recycled materials should not be used for electroplating ABS.
2. Selection of injection molding machine
The standard injection molding machine of Ramada can be selected (the length diameter ratio of screw is 20:1, the compression ratio is greater than 2, and the injection pressure is greater than 1500bar). If the color masterbatch is used or the appearance of the product is high, the screw with a smaller diameter can be selected. The clamping force is determined according to 4700-6200t / m2, which depends on the plastic grade and product requirements.
3. Mold and gate design
Mold temperature can be set at 60-65 ℃. The channel diameter is 6-8mm. The gate width is about 3 mm, the thickness is the same as the product, and the gate length is less than 1 mm. The exhaust hole is 4-6mm wide and 0.025-0.05mm thick.
4. Temperatura topnienia
It can be accurately determined by air injection. According to different grades, the melt temperature is also different. It is suggested to set as follows:
Impact grade: 220 ℃ – 260 ℃, 250 ℃ is better
Electroplating grade: 250 ℃ – 275 ℃, 270 ℃ is better
Heat resistant grade: 240 ℃ – 280 ℃, 265 ℃ – 270 ℃
Flame retardant grade: 200 ℃ – 240 ℃, 220 ℃ – 230 ℃ is better
Transparent grade: 230 ℃ – 260 ℃, 245 ℃ is better
Glass fiber reinforced grade: 230 ℃ – 270 ℃
For products with high surface requirements, higher melt temperature and mold temperature are used.
5. Injection rate
The fire grade should use slow speed, and the heat grade should use fast speed. If the surface requirement of the product is high, the shooting speed of high-speed and multi-stage injection should be controlled.
6. Ciśnienie zwrotne
Ogólnie, the lower the back pressure is, lepiej. The commonly used back pressure is 5bar. The dyeing material needs higher back pressure to make the color mixing uniform.
7. Residence time
Nie bój się, gdy forma się zdeformuje 265 ℃, the residence time of ABS in the melt can not exceed 5-6 minutes at most. The flame retardant time is shorter. If the machine needs to be stopped, the set temperature should be lowered to 100 ℃ first, and then the general-purpose ABS can be used to clean the glue cartridge. The cleaned mixture should be put into cold water to prevent further decomposition. If you need to change from other plastics to ABS material, you need to use PS, PMMA or PE to clean the glue cartridge. Some ABS products have no problem when they are just demoulded, and they will change color after a period of time, which may be caused by overheating or too long residence time of the plastic in the melt cartridge.
8. Post treatment of products
General ABS products do not need post-treatment, only electroplating grade products need to be baked (70-80 ℃, 2-4 godziny) to passivate the surface traces, and the products that need to be electroplated can not use mold release agent, and the products should be packed immediately after they are taken out.
9. Matters needing special attention during molding
There are several grades of ABS (especially flame retardant grade). After plasticization, the adhesive force of the melt on the screw surface is very large, and it will decompose after a long time. When the above situation occurs, it is necessary to pull the homogenizing section and compression screw out for wiping test, and regularly clean the screw with PS, itp.
O JasonMould Industrial Company Limited
Jasonmould jest Chiny producent form plastikowych form- forma wtryskowa, formy odlewnicze, formowanie z rozdmuchiwaniem z tworzywa sztucznego,, formowanie rotacyjne, medyczny formowanie wtryskowe tworzyw sztucznych, dwa strzały formowanie wtryskowe tworzyw sztucznych, wkładka do formowania, obtryskiwanie, formowanie wtryskowe metalu, mikroformowanie wtryskowe, formowanie wtryskowe proszków, ceramiczne formowanie wtryskowe, płynne formowanie wtryskowe, husky formowanie wtryskowe, pleśń domowa, odlewanie formy, narzędzie do formowania matrycy, niestandardowe formy, formy z porcelany, oprzyrządowanie do szybkiego prototypowania, oprzyrządowanie do prototypowania tworzyw sztucznych, oprzyrządowanie do dziurkowania, matryca i oprzyrządowanie do części do telefonów komórkowych / telefonów komórkowych cell, części samochodowe, odkurzacze, narzędzia ładowalne, telefony, kopiarki, komputery, głośniki multimedialne, oraz wiele innych produktów elektronicznych i AGD. A także producent wyrobów z tworzyw sztucznych, producent form Chiny- plastikowe części, plastikowy zbiornik na wodę, plastikowe kulki, plastikowe pojemniki, plastikowa klamra, plastikowa kotwica, plastikowy wieszak, plastikowa łyżka, plastikowa złączka do rur,, plastikowe upadki, plastikowe zastawy stołowe, plastikowe kubki, plastikowe butelki, Taca z tworzywa sztucznego, plastikowy pojemnik kosmetyczny, plastikowa obudowa, plastikowy pojemnik na żywność, plastikowe krzesła, plastikowe nasadki, plastikowe zamknięcie nasadki, plastikowe rurki, plastikowe rury wodne, plastikowe gałki, plastikowe rurki, plastikowe pudełka na narzędzia, plastikowe stojaki i tak dalej.
Kontakt:
Osoba: James Yuan
Firma: JasonMould Industrial Company Limited
Dodaj: Wioska LongGang,Miasto LongXi,Hrabstwo BoLuo,Miasto HuiZhou,Prowincja Guangdong, Chiny
Tel: 86-752-6682869
E-mail: [email protected]
Teren: https://www.jasonmolding.com/custom-injection-molding/
