TVCd Double Chamber Pressure Over Vacuum Casting Machine Topcast s.r.l. Loc. San Zeno, strada C, 6/D 52100 Arezzo (AR) ITALIA phone: +39 0575 441341 – fax: +39 0575 441222 phone: e-mail: firstname.lastname@example.orgRev.21.07.06
Fully Automatic Operation100 Programs to cast different alloys and designes11 parameters per program, describing: Gas purging and oxygen removal Melting and Homogenising phase Flask vacuuming Metal injection control Compression control during solidification phase Cooling phaseMaximum repeatibilityEasy to useSynoptic display with Touch Screen for cycle supervisionAutotest function for a deep check of the machine
Incorrect Melting of the AlloyTypical situation in which insufficient stirring leadsto an imperfect melting and homogenisationThis problem is reflected directly on the surfacequalityNo matter how much you will try to finish yourrings, the problem will stay there, in depthDifference in gold title are found after fire assaytest
Correct Melting of the AlloyArgon or Helium gas washing beforemeltingAdvanced Self Tuning thermoregulation(AST™) with exact temperature control ofthe melted alloysTwo Set-Points available: Homogenizationand Casting TemperatureMedium frequency induction heating stirsthe melted alloy and leads to a perfecthomogeneityPulse Stirring Management (PSM™) for anextremely low frequency stirringHighest power density in the marketfeatures strongest stirring and low goldlosses
Gas Washing ProcedureCrucible loading operation introducesoxygenThe Gas Wash procedure first removethe oxygen (1) and then refill back thechambers with Argon or Helium gas (2)Compared with the traditional crucibleprotection with flow-meter regulation theconsumption of gas is dramatically OXYGEN CONTENT DURING HEATINGreduced and the alloys oxidation is 100 90minimized (see picture) 80 70 60 %Moreover the crucible life is increased: 50 40 30TVC series crucible last up to 250 – 400 20 10casting according to the graphite quality 0 time Gas Wash Competitor Temperature
Flask vacuuming before castingTVC is the only casting machine todayavailable with static gas sealing (SGS™)between melting and flask chamberThis unique feature leads to a perfectvacuum in the flask before castingMetal entering the mould can fill whateverspace without suffering any counter-pressure due to the residual gas trappedinside the mouldNo gas leakage will affect the accuracy ofyour casting from filigree to large surfacepartsMoreover, you can use simple steel pipes.No needs of perforated or flanged flasksBeside being cheaper these flask are alsomuch safer because they avoid metalspilling out of the flask in case theinvestment breaks down.
Injection and CompressionWhen the stopper lifts up, it is very important tocontrol the injection rate to avoid turbulencesTVC has the unique feature to have the injectionrate controllable and programmable (IRC™)The metal enters smoothly inside the mould.Then, after filling and during the solidificationphase, a strong compression takes place on thetreeNo turbulences in filling and high compressionrate lead to a large reduction of shrinkageporosity phenomenaThe faster injection available in the doublechamber system will give you also the ability tocast at a lower temperature, improving thesurface quality
Protecting the tree after castingAfter the solidification phase and thanks to thechambers independence, the flask will cooldown in a protective atmosphere while you canload your alloy in the melting chamber for thenext castingThis way you will prevent your tree fromoxidation also during the cooling phaseobtaining lower finishing work with great savingin gold lossesWhile the previous flask is cooling in the lowerchamber, you can load new alloys in thecrucible for the following flask, overlapping thecasting cycle and hence saving timeNo other machine can work in OverlappingMode without oxidise the metalMoreover, overlapping mode shortens thecasting time. Flask to flask in just 3 minutes!!!
A new Standard: 400 mm flaskThanks to the described features, today anew standard with flask up to 400 mm iscoming in many jewellery factoriesThis brings many benefits in terms of highermetal yield and lower running costYou can have the same final production byusing much less precious metal in yourfactory reducing so also the refining losses.A daily production of 20 flasks of 400 mminstead of 40 flasks of 200 mm in height willgive you a saving of more than 2000 g goldconsidering just the conical pour cupdifferences.And you will cast the half times, savingcrucibles consumption, argon, investmentpowder, electricity and operator time.Moreover, one taller burnout oven will makethe job of two, saving space and energy.
Double Chamber The future available todayCorrect melting and alloyhomogenizationReal vacuum directly inside the flask formaximum details reproductionResults and quality consistency becausethe system is free from flask to flaskpermeability differencesFaster injection for lower temperaturecasting and better surface finishingIncreased metal yieldReduced consumables costReduced operation time