Action and function
Character
Fast action speed
Principle of shutdown is that piston and valve is connected by lever. When molten metal collides on piston, piston and valve will be backward at the same time. Both NVV and SVV series share the same shutdown principle.
Easy to do maintenance
It is unnecessary to dismantle mold while do maintenance of valve. The main part of maintenance includes exchange the consumption parts like piston, valve, piston bush and valve bush.
Vacuum suction・Molten metal shutdown structure
Vacuum suction starts before injection of molten metal and finishes before molten metal comes into cavity of mold.
Explanation of vacuum valve structure and action summary
| 1 | After mold is closed, the lock of valve and piston is relieved and gets ready to do vacuum suction. |  |
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| 2 | Gas of cavity discharges from the gate which connects valve and mold liner. When molten metal collides on piston, valve is backward at the same time. Attention Vacuum valve closes smoothly at high speed intensified pressure die casting mode. During try shot or low speed ・high speed die casting mode, valve cannot close normally. |
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| 3 | When mold is open, power of springs push lever forwardly and piston and valve move forwardly at the same time. |  |
Valve protection function（Valve protection air）
During try shot or low speed・high speed die casting, valve cannot close normally.
Please supply air to inside of valve to keep valve closing all the time.
Signal output from die casting machine ensures this function works automatically.
Action summary
Please connect valve protection air tube to vacuum valve like picture shows below.
Air supply collides on cylinder to close valve.
Please make sure air pressure is about 0.45 MPa
Stable air（Corresponding model only）
In order to get stable action of vacuum valve, lubricant spray and air blow to cool valve and piston is necessary.
Like picture below shows air goes out from two places.
