magmuskler, allmänt känd som akrylnitrilbutadienstyren, tillverkas genom sampolymerisation av akrylnitrilbutadienstyren. På grund av de olika proportionerna av de tre monomererna, ABS med olika egenskaper och smälttemperatur kan utökas till ABS med olika användningsområden och egenskaper, such as impact grade, heat resistance grade, flame retardant grade, transparent grade, reinforced grade, electroplating grade, etc., 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. Därför, 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 kärnhårdheten 46-50HRC, the thickness is the same as the product, and the gate length is less than 1 kärnhårdheten 46-50HRC. The exhaust hole is 4-6mm wide and 0.025-0.05mm thick.
4. högprecisionsformsprutning av plast
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. Back pressure
vår, the lower the back pressure is, desto bättre. The commonly used back pressure is 5bar. The dyeing material needs higher back pressure to make the color mixing uniform.
7. Residence time
Dessa innehåll är huvudorsakerna som påverkar bearbetningsnoggrannheten hos formar 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 timmar) 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, etc.
Om JasonMould Industrial Company Limited
Jasonmould är en Kina mögel tillverkare av plastformar- formsprutning, gjutformar, formblåsning av plast, rotationsgjutning, medicinsk formsprutning av plast, två skott formsprutning av plast, insatsgjutning, övergjutning, formsprutning av metall, formsprutning av mikro, formsprutning av pulver, keramisk formsprutning, formsprutning av vätskor, husky formsprutning, hushållsform, gjutform, formverktyg, anpassade formar, porslinformar, snabb prototypverktyg, verktyg för plastprototyp, stanspressverktyg, munstycke och verktyg för mobildelar/ mobiltelefondelar, bildelar, Dammsugare, uppladdningsbara verktyg, telefoner, kopiatorer, datorer, multimediehögtalare, och många andra elektroniska produkter och hushållsapparater. Och även en tillverkare av plastprodukter, mögeltillverkare Kina- plastdelar, vattentank i plast, plastbollar, plastlådor, plastspänne, plastankare, plasthängare, plastsked, rörmontering av plast, tumla av plast, porslin av plast, plastmuggar, plastflaska, plastbricka, kosmetisk behållare av plast, plastfodral, matbehållare av plast, stolar i plast, plastlock, stängning av plastlock, plaströr, vattenledningar av plast, knoppar i plast, plaströr, verktygslådor i plast, plastställ och så vidare.
Kontakt:
Person: James Yuan
Företag: JasonMould Industrial Company Limited
Lägg till: LongGang Village,LongXi Town,BoLuo County,HuiZhou City,GuangDong-provinsen, Kina
Tel: 86-752-6682869
E-post: [email protected]
Webbplats: https://www.jasonmolding.com/custom-injection-molding/
