Høj konsistens gummi (HCR) or Heat Cured Rubber (HCR) is an injection molding technique used to create equipment with high consistency polymeric silicone that is resilient and elastic.
The Strong Consistency Rubber (HCR) is a flow plate with a high resistance to flow and little elasticization. Høj konsistens gummi (HCR) is suitable for tough environmental circumstances because it has excellent shock absorption, heat and cold resistance, and electrical conductivity.
What is High Consistency Rubber（HCR）？
Fast silikonegummi (Nogle gange omtalt som højkonsistens silikone gummi, eller HCR), som hærdes ved høje temperaturer ved hjælp af enten organiske peroxider eller en platinekatalysator. HCR har en fast konsistens, fordi den omfatter lange polymerkæder med en høj molekylvægt. HCR er ansat i en række statiske og dynamiske applikationer på grund af dets ekstraordinære mekaniske egenskaber, inklusive:
- Automotive
- Rumfart
- Elektrisk transmission og distribution
- Ledning og kabel
- Fødevareforarbejdning
- Støbte gummiprodukter
Fremragende aldring og temperaturmodstand tilvejebringes af HCR. Konventionelle teknikker inklusive ekstrudering, Kalending, komprimering, og injektionsstøbning kan bruges til at behandle den.
The HCR Injection Molding Process​
Solid silicone rubber is produced in bulk by rubber producers, who combine the ingredients in an uniform mixture at high temperatures. The curing process is facilitated by the inclusion of peroxide catalyst. Fabricators start the cross-linking of the molecules, but roll out the sheets of rubber materials before the vulcanization process is finished for storage or transportation.
The actual silicone rubber manufacturing process entails six steps:
- Katalysation og blødgøring af møller
Denne oprindelige proces vender enhver "Crepe -hærdning" Det forekommer som et resultat af det materiale, der opbevares hos leverandøren eller fabrikatoren og er nødvendig for både ekstruderings- og støbningsapplikationer. Derudover, some procedures employ milling to combine the two components of an extra cure elastomer before processing or to add peroxide catalysts as needed to a free radical elastomer. A two-roll mill is required for this time-consuming procedure since the elastomer must go through the mill more than once to combine the complex material into a homogenous final result. The sheet might need to be processed further once it has been taken out of the mold.
- Konstruere en præform
The preparation of a performance comes next, which entails a lot of work, especially in high-volume production settings that run continuously. Et stik, der passer i overførselsreservoiret på overførselspressen, skal klippes fra præformen med en die-cutter som en del af overførselsstøbningsproceduren. Due to the requirement that the preform be cut into the same shape as the finished component, the compression molding application involves a more involved procedure. The elastomer sheet is cut into strips and fed into the extruder to prepare the preform for the extrusion and injection molding applications.
- Ekstrudering
En enkelt-skrue ekstruder bruges i ekstruderingspressen til HCR. Et rullefoderhjul bruges af operatøren til at fodre præfabrikerede strimler i en ekstruder. The elastomer material is extruded through a die and mandrel assembly, which equips the extruder with a crosshead assembly to form the required profile. Det "support extrude" processing option uses a crosshead assembly that is mounted on the extruder to pass the supporting geometry through it and extrude a layer of silicone rubber over it.
- Støbning
Forskellige støbningsværktøjer er nødvendige til forskellige silikone-applikationer med høj konsistens. Personnel are needed to load the elastomer into the machinery and to de-mold the completed components during both transfer and injection molding manufacture. In order to complete the compression molding process, employees must insert preforms into each mold's cavity. Due to the long cure cycles of high consistency rubber, the molds may have several holes.
- Vulkanisering
Extruded goods are vulcanized by fabricators using hot-air vulcanizing ovens (HAVs). By creating molecular cross-links, this process makes the material stronger and more resilient. Den ekstruderede profil trækkes op gennem ovnen i den lodrette ovn, som fås i både lodrette og vandrette varianter. Radiant heat or a steam autoclave oven are used in some vulcanization procedures.
- Finishing
The application determines how much finishing is done. The finishing procedure for extrusion profiles involves a visual examination and cutting the tubes into predetermined lengths. The profile has to go through a post-cured procedure to get rid of the peroxide byproducts for extrusion components that are peroxide cured. Trimming or de-flashing of molded components is another step in the injection molding process. The employee cuts the components off the huge, molded sheet using a die-cutting tool. The component can need post-curing in specific circumstances.
Material is wasted during the production of high-consistency rubber, and labor is expensive. Derudover, physical labor and other tools and equipment are needed. Imidlertid, the equipment is less costly than the molds needed to make items made of LSR (flydende silikonegummi).
Hvornår er høj konsistens gummi (HCR) Det bedste valg?
Høj konsistens gummi (HCR) Injektionsstøbning er ofte den foretrukne metode, når man producerer udstyr og materialer til bilindustrien, Elektrisk, biomedicinsk, og farmaceutiske industrier. Høj konsistens gummi (HCR) udviser høj modstand mod temperatur, er en fremragende støddæmper, og er en god elektricitetsleder.
Høj konsistens gummi (HCR) er den fineste mulighed for fremstilling af kabler, Tændrørstøvler, Elektriske isolatorer, rør, Luftfartsudstyr, og andet forseglet udstyr, fordi det til dets stærke varmemodstand, brandmodstand, og lav røgudladning.
Because the procedure isn't adaptable enough for automated replication needed for mass production runs, Den høje konsistensgummi (HCR) Støbningsmetode er den bedste mulighed i tilfælde af stor fremstilling.