Pressure Over Vacuum Casting Machine

Pressure over Vacuum Casting Machine, Double Chamber

TVCd is the pressure over vacuum casting machine designed to meet the more severe needs in lost wax casting production.
This machine works with a new, revolutionary double chamber concept. This innovative system gives several advantages compared with the traditional single chamber suction system currently available in the market.
In TVCd melting chamber and flask chamber are completely indipendent and at the moment of casting the machine can control the metal injection into the mold by applying a differential pressure during pouring.
This yields to a faster injection compared to the simply gravity pouring with the benefit to cast items at lower temperature. This will result in better surface finishing of the cast parts.
The casting cycle takes only few minutes and, while the previous flask is cooling down in protective gas for no oxidation, the next charge can be loaded into the crucible and melted, thus overlapping two cycles for no time waste. 
The machine is fully automatic having also a PC based monitoring system for process parameters acquisition and production data management with easy editing of casting programs suitable for many kind of alloy (optional).
This revolutionary machine is the synthesis of the most advanced engineering and years of experience in casting that only TOPCAST will bring in your factory.

 

Gas Wash Procedure

• Crucible loading operation introduces oxygen
• The Gas Wash Purge procedure removes the oxygen (1) in a very fast and efficient way and then refills back the chambers with Argon or Helium gas (2)
• Compared with the traditional crucible protection with flow-meter regulation the consumption of gas is dramatically reduced and the alloys oxidation is minimized
• Moreover the crucible life is increased: TVC series crucible last up to 250 – 400 casting cycles according to the graphite quality

Melting

• Advanced Self Tuning thermoregulation (AST™) with exact temperature control of the melted alloys
• Two Set-Points available: Homogenization and Casting Temperature
• Medium frequency induction heating stirs the melted alloy and leads to a perfect homogeneity
• Pulse Stirring Management (PSM™) for an extremely low frequency stirring
• Highest power density in the market features strongest stirring and low gold losses

 Injection and Compression

• When the stopper lifts up. it is very important to control the injection rate to avoid turbulences
• TVC has the unique feature to have the injection rate controllable and programmable (IRC™)
• The metal enters smoothly inside the mould (4). Then, after filling and during the solidification phase, a strong compression takes place on the tree (5)
• No turbulences in filling and high compression rate lead to a large reduction of shrinkage porosity phenomena

Tree protection after casting

• Thanks to the double chamber concept, after the solidification phase, the flask cools down in a protective atmosphere while at the same time you can load your alloy in the melting chamber for the next melting.
• This operation will allows an overlapping of the casting cycles which will give you the ability to protect longer the tree before removing it without loosing time and productivity