70.7 Rezumat, Referințe

În general, sculele soft (directe sau indirecte) sunt utilizate pe scară largă pentru produse turnate unice și în loturi mici. Pentru scopuri de turnare unică în turnarea cu modele fuzibile, pot fi fabricate piese cu proprietăți mecanice și fizice identice cu piesele produse prin turnarea convențională. Prin urmare, piesele produse prin RT pot fi utilizate și aplicate în aplicația dorită reală. Pentru producția de loturi mici, sculele soft sunt utilizate în principal pentru fabricarea de prototipuri cu proprietăți funcționale necesare pentru testare înainte de finalizarea modelului.
Generally, soft tooling (direct or indirect) is widely used for single cast and small batch product. For single cast purposes in investment casting, parts with mechanical and physical properties identical to parts produced by conventional investment casting can be manufactured. Hence, parts produced by RT can be used and applied in actual intended application. For small batch production, soft tools are mostly used to manufacture prototypes with functional properties required for testing before the finalization of the design.

Sculele de turnare în sculele hard sunt de obicei produse direct (deși pot fi produse indirect) datorită capacităților ridicate de proces ale tehnicilor AM ca urmare a progreselor tehnologice (Cheah et al. 2005). Ele posedă proprietăți mecanice ridicate și durabilitate necesare ca sculă hard cu durată lungă de viață. În plus, ele prezintă proprietăți funcționale, deoarece pot fi construite cu canale de răcire conforme interne. Sculele hard în RT sunt, în general, destinate producției de volum mare în fabricarea de piese sau componente reale care pot fi utilizate sau testate în aplicația prevăzută.
Molding tools in hard tooling are usually produced directly (although they may be produced indirectly) due to high process capabilities of AM techniques as a result of technological advances (Cheah et al. 2005). They possess high mechanical properties and durability required as a hard tool with long tool life. In addition, they exhibit functional properties as they can be built with internal conformal cooling channels. Hard tooling in RT is generally meant for large volume production in the manufacturing of actual parts or components that can be used or tested for in the intended application.

Există mai multe beneficii aduse de RT, cele mai evidente fiind economiile de costuri și timp. Pentru inginerul de producție, RT minimizează proiectarea, fabricarea și verificarea sculelor. Costurile fixe sunt mult reduse cu cheltuieli minime de asamblare, achiziție și inventar. În consecință, costurile cu forța de muncă și inspecția sunt reduse corespunzător. Costurile sunt reduse și mai mult, împreună cu flexibilitatea în producție în RT, deoarece mai puține stocuri sunt casate la modificările de proiectare, împreună cu investițiile mai mici necesare pentru producția de scule. Acest lucru este valabil mai ales în dinamica unei piețe competitive în care noi produse pot fi lansate rapid pentru a satisface cerințele în schimbare (Chua și colab. 1999b).
There are several benefits brought by RT with the most evident being cost and time savings. To the manufacturing engineer, RT minimizes design, manufacturing, and verification of tooling. Fixed costs are greatly reduced with minimal assembly, purchase, and inventory expenses. Consequently, labor and inspection costs are reduced accordingly. Costs are further reduced along with flexibility in manufacturing in RT because fewer inventories are scrapped upon design changes along with lower investment necessary for tool production. This is especially true in the dynamics of a competitive market where new products can be launched quickly to meet changing demands (Chua et al. 1999b).

Avantajele suplimentare ale RT în fabricarea matrițelor și industria de prelucrare a materialelor plastice includ acuratețea dimensională crescută, prin care defectele pot fi evitate și piesele sunt îmbunătățite din punct de vedere estetic. Timpul ciclului de producție poate fi, de asemenea, redus cu până la 50% în turnarea prin injecție datorită răcirii mai rapide. Inserțiile pentru miez și cavitate pot fi ușor modificate sau reparate, ceea ce contribuie la o rentabilitate scurtă a investiției. În industria turnării sub presiune, inserțiile de scule cu canale de răcire conforme ajută la minimizarea sau eliminarea defectelor de suprafață ale matriței și a celor termice. Punctele fierbinți pot fi eliminate sau reduse, crescând calitatea turnării atât în ​​ceea ce privește caracteristicile dimensionale, cât și geometrice, împreună cu integritatea ridicată a structurii materialului. În mod similar, timpul de ciclu este redus și durata de viață a sculei este crescută.
Additional advantages of RT in mold making and plastic processing industry include increased dimensional accuracy whereby defects can be avoided and parts are improved in aesthetic wise. Production cycle time can also be reduced by up to 50 % in injection molding due to faster cooling. Core and cavity inserts can be easily modified or repaired which contributes to short return on investment. In the die casting industry, tool inserts with conformal cooling channels help to minimize or eliminate thermal-related mold and mold surface defects. Hot spots can be eliminated or reduced, increasing casting quality in terms of both dimensional and geometrical features coupled with high material structure integrity. Similarly, cycle time is reduced and tool life is increased.

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