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Hydrogen is our friend or foe. Depending on the type of casting you produce, hydrogen absorption by molten aluminum can be helpful or harmful.

With the Vac-U-Check you are assured a quick, simple, economical, and accurate method of monitoring the hydrogen level in your melt.

A vacuum solidified sample exaggerates the hole size, making the analysis of gas in the sample easy to determine by visual methods or by using the specific gravity formula.

The use of a Vac-U-Check unit is simple. Dip a 1/4 pound molten aluminum sample from your furnace. Place the sample in the vacuum chamber for solidification. After the sample is cool, saw it in half for a visual inspection or weigh the sample in air and water to determine the true specific gravity.

Should your castings be at the premium level, a minimum amount of gas is required. If you are producing a commercial casting, a small amount of gas can be helpful in reducing shrinkage, thus simplifying gating, risering, chill usage, and improving yield. See the samples above and note shrinkage difference in the sample solidified in air.

Contact us for more information.








Hall booth #346

Defect Prevention in
Permanent Mold Casting
Through Process Control.


By John Hall

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