TPE-bobler og hulrum refererer for det meste til hulrummene genereret inde i den tykke væg af den støbte del. Det ydre hus af den støbte del kondenseres og størkner ved sprøjtestøbning, og mængden af smelten er utilstrækkelig i forhold til hele delen, derved genereres vakuumhuller, som generelt forekommer. På steder, hvor produktet er tykt og ved indløbet. Det kaldes en boble eller et tomrum. Generelt sagt, if a bubble is found at the moment of opening, it is a gas interference problem.
The formation of vacuum bubbles is due to insufficient filling or low pressure. Under the rapid cooling of the mold, the molten material in contact with the cavity is involved, resulting in a volume loss.
In this sense, the term “boble” is not appropriate, at least in the moment after the formation, there is no air in the hole. Bubbles generated by this reason cannot be said to be defects of molded parts, but most of them are not problematic as opaque or colored parts. Imidlertid, it is necessary to eliminate the bubbles in the roots of the main runner of the transparent part and the sprue.
1. Når man laver en masse knapper og andre små plastikdele: (similar to the sink marks)
2. Skimmelsvamp: thick-walled parts.
3. Processen: this is the same as the reason for the lack of compression to produce sink marks. Derfor, it is necessary to increase the diameter of the main runner, sprue and gate, reduce the temperature of the melt, raise the temperature of the mold, and use a plastic with poor fluidity to ensure sufficient injection and holding time and reduce the injection speed. Imidlertid, for thick-walled parts and crystalline plastics, most of them cannot eliminate the voids even if necessary measures are taken. Non-transparent parts produce several shrinkage holes without any hindrance. For parts that do not allow bubbles, the shrinkage holes are not considered, so that no bubbles are generated inside, the mold can be demolded before the wall thickness portion is fully hardened, and then immersed in slow cooling in warm water, this method is sometimes effective in preventing bubbles.
Af denne grund, the bubble is exactly the same as the reason why the uneven cooling produces a shrinkage cavity. Derfor, the method of preventing defects is also the same, and eliminating bubbles is theoretically difficult. Derfor, it is important to avoid designing the desired part into a shape that is prone to bubble formation. Slow cooling in warm water is also effective.
4. Plast: When TPE plastics contain moisture or volatile components, and plastics or added components are decomposed into gas in the cylinder, bubbles are injected into the cavity as the melt is injected. When bubbles are generated due to volatile components or moisture, the bubbles can be eliminated by improving the back pressure and sufficiently cooling the lower portion of the hopper to improve the exhaust in the cylinder while sufficiently drying the raw material. Bubbles can be eliminated by overheating decomposition, lowering the melt temperature, and shortening the residence time of the melt in the barrel.
5. Some TPE plastic parts quickly swell or swell on the back of the metal insert or in a particularly thick part after the mold is demolded.
This is because the plastic that is not completely cooled and hardened is caused by the release of gas under the action of internal pressure.
Løsning:
1. Effektiv køling. Reduce the mold temperature, extend the mold opening time, and reduce the drying and processing temperature of the material.
2. Reducer påfyldningshastigheden, reducere formningscyklussen og reducere strømningsmodstanden.
3. Increase holding pressure and time.
4. Improve the condition that the wall of the part is too thick or the thickness changes greatly.
Om JasonMould Industrial Company Limited
Jasonmould er en Kina mold maker af plastforme- sprøjtestøbeform, formstøbning forme, plastblæsestøbning, rotationsstøbning, medicinsk plast sprøjtestøbning, to skud plast sprøjtestøbning, indsatsstøbning, overformning, metal sprøjtestøbning, mikro sprøjtestøbning, pulverformsprøjtning, keramisk sprøjtestøbning, flydende sprøjtestøbning, husky sprøjtestøbning, husholdningsskimmel, støbeform, formværktøj, brugerdefinerede forme, porcelæn forme, værktøj til hurtig prototyping, værktøj til prototyper i plastik, slagpresseværktøj, dør og værktøj til mobiltelefon/ mobiltelefondele, bildele, støvsugere, genopladelige værktøjer, telefoner, kopimaskiner, computere, multimediehøjttalere, og mange andre elektroniske produkter og husholdningsapparater. Og også en plastproduktproducent, skimmel producent Kina- plastikdele, vandtank i plast, plastik bolde, plastbeholdere, plastspænde, plastanker, plast bøjle, plastske, rørledning i plast, tumlet plast, bordservice i plast, plastik kopper, plastik flasker, plastbakke, kosmetisk beholder af plast, plastkasse, madbeholder i plast, plaststole, plastikkapper, lukning af plasthætte, plastrør, vandrør i plast, plastik knapper, plastrør, brugskasser i plast, plaststativer og så videre.
Kontakt:
Person: James Yuan
Selskab: JasonMould Industrial Company Limited
Tilføje: LongGang Village,LongXi Town,BoLuo County,HuiZhou City,GuangDong-provinsen, Kina
Tlf: 86-752-6682869
E-mail: [email protected]
Websted: https://www.jasonmolding.com/low-volume-manufacturing/
