Somo 1Kupungua na tabia ya kupaka: kupungua kwa volumetric na molded, kinetics za kupaka, udhibiti wa exotherm, na mazingatio ya baada ya kupakaSehemu hii inaelezea kupungua kwa thermoset na tabia ya kupaka, ikishughulikia kupungua kwa volumetric na molded, kinetics za kupaka, udhibiti wa exotherm, na mikakati ya baada ya kupaka, na inaonyesha jinsi sababu hizi zinavyoathiri ubuni wa zana, uvumilivu, na uthabiti wa sehemu.
Volumetric versus molded shrinkageCure kinetics and degree of conversionExotherm management in thick sectionsMold design for shrinkage compensationPost‑cure cycles and property developmentSomo 2Kutafsiri karatasi za data za kiufundi (TDS) kwa misombo ya molding ya thermoset: Tg, ratiba ya kupaka, joto la mold lililopendekezwa, viscosity na data ya mtiririkoSehemu hii inafundisha jinsi ya kusoma karatasi za data za kiufundi za thermoset, ikilenga Tg, ratiba za kupaka, joto la mold lililopendekezwa, data ya viscosity na mtiririko, na jinsi ya kutafsiri vigezo hivi kuwa madirisha thabiti ya molding na maamuzi ya zana.
Locating key data sheet parametersInterpreting Tg and heat deflection dataCure schedule and mold temperature windowsViscosity, spiral flow, and gel time dataLinking TDS values to process settingsSomo 3Sifa kuu za nyenzo zinazohusiana na makao ya swichi: uthabiti wa joto, nguvu ya dielectric, nguvu ya kimakanika, joto la mpito wa glasi, kipengele cha upanuzi wa joto, na kunyonya unyevuSehemu hii inaelezea mali za nyenzo muhimu kwa makao ya swichi, ikijumuisha uthabiti wa joto, nguvu ya dielectric, nguvu ya kimakanika, joto la mpito wa glasi, kipengele cha upanuzi wa joto, na kunyonya unyevu, na jinsi vigezo hivi vinavyoathiri mipaka ya ubuni na majaribio.
Thermal stability and long‑term heat resistanceDielectric strength and tracking resistanceMechanical strength and impact performanceGlass transition temperature and service windowCTE, moisture uptake, and dimensional changeSomo 4Maelekezo ya ubuni kwa ribs nyembamba, bosses, na mpito wa ukatu ili kuepuka kujaza kutokamilika na warpageSehemu hii inaelezea maelekezo ya ubuni kwa ribs nyembamba, bosses, na mpito wa ukuta ili kuepuka kujaza kutokamilika na warpage.
Recommended wall and rib thickness ratiosBoss design for inserts and screw retentionFillets, radii, and smooth wall transitionsGate location impact on filling thin featuresDraft angles and demolding of brittle partsSomo 5Utunzaji na uhifadhi wa nyenzo: unyevu, mahitaji ya preheating/kukausha, pot life au shelf life ya misombo ya molding na prepregsSehemu hii inashughulikia uhifadhi na utunzaji wa misombo ya molding ya thermoset na prepregs, ikijumuisha unyeti wa unyevu, preheating au kukausha, pot life, shelf life, na mazoea ya traceability yanayohifadhi mtiririko thabiti na tabia ya kupaka katika uzalishaji.
Storage temperature and humidity controlsPackaging, sealing, and labeling practicesPreheating and drying of molding compoundsPot life management during shift operationsShelf life, requalification, and traceabilitySomo 6Viongezi na vujari vya kawaida: reinforcements (glasi fibers, vujari vya madini), flame retardants, colorants — athari kwenye mtiririko, kupaka, na mali za mwishoSehemu hii inaangalia viongezi na vujari vya kawaida katika misombo ya thermoset kwa makao ya swichi, kama vile glasi fibers, vujari vya madini, flame retardants, na colorants, na inaelezea athari zao kwenye viscosity, kupaka, nguvu ya kimakanika, na tabia ya umeme.
Glass fiber reinforcement and orientationMineral fillers and dimensional stabilityFlame retardant systems and UL ratingsColorants, pigments, and surface appearanceAdditive effects on flow and cure kineticsSomo 7Muhtasari wa familia za thermoset za kawaida: phenolic (PF), melamine (MF), unsaturated polyester (UP), na epoxy — kemia na mifumo ya crosslinkingSehemu hii inatanguliza familia kuu za thermoset zinazotumiwa katika makao ya swichi, ikijumuisha phenolic, melamine, unsaturated polyester, na mifumo ya epoxy, ikielezea kemia yao ya msingi, athari za kupaka, unene wa crosslink, na envelopes za utendaji wa kawaida.
Phenolic resins: novolac and resol systemsMelamine and related amino thermosetsUnsaturated polyester molding compoundsEpoxy molding compounds for switchgearCrosslink density and network structureSomo 8Mazingatio ya mazingira, afya, na udhibiti wa nyenzo: pumzi, uzalishaji wakati wa kupaka, na vitu vya karatasi ya data ya usalama wa nyenzo (MSDS) vinavyohitajikaSehemu hii inashughulikia pumzi na uzalishaji wakati wa kupaka kwa thermoset, vitu muhimu vya MSDS na SDS, mipaka ya mfiduo wa mahali pa kazi, uingizaji hewa, PPE, na miundo ya udhibiti inayodhibiti utunzaji salama wa misombo ya molding katika uzalishaji wa vifaa vya umeme.
Typical emissions during thermoset curingKey MSDS and SDS sections for operatorsVentilation and local exhaust requirementsPersonal protective equipment for moldingRegulatory exposure limits and complianceSomo 9Kulinganisha: kwa nini thermosets zinachaguliwa zaidi ya thermoplastics kwa switchgear ya voltage ya chini — uthabiti wa vipimo, upinzani wa joto, flame retardancy, na kuzeekaSehemu hii inalinganisha thermosets na thermoplastics kwa switchgear ya voltage ya chini, ikiangazia faida katika uthabiti wa vipimo, upinzani wa joto, flame retardancy, na tabia ya kuzeeka, na inaelezea trade-offs katika uchakataji, recyclability, na gharama.
Dimensional stability under load and heatHeat resistance and thermal index ratingsFlame retardancy and glow‑wire performanceCreepage, tracking, and insulation ageingProcessing, recyclability, and cost trade‑offsSomo 10Hali za kushindwa maalum kwa thermosets: kupasuka kwa ndani, embrittlement, kasoro za uso, na uharibifu wa mazingiraSehemu hii inachunguza hali za kushindwa maalum kwa thermosets: kupasuka kwa ndani, embrittlement, kasoro za uso, na uharibifu wa mazingira.
Internal cracking and residual stressesEmbrittlement from ageing and over‑cureSurface defects, sinks, and flow marksEnvironmental stress and chemical attackInspection, testing, and failure analysis
