Cold shut occurence

Hi: I have encountered a cold shut occurence (identified) by third party material lab for a manifold casting as the cause of leakage.Also, the report says that they found shrinkage in the material at the inlet of the fluid.
I want to know the basic definition of cold shut?also, what are the likely chances of it occuring in a design part ( which can be manufactured by forging or by casting) Kindly, advise.
Thanks, neil

Neil, If I understand your question, the "cold shut" you are speaking of it is where the metal has solidified before it completely filled the mold. "Shrink porosity" is also a common defect, it often occurs but not always at the gate entering the mold. In casting it is necessary to control the direction of solidification when cooling. So your manifold pattern may need the addition of "chills" to start the solidification in certain places and the gating system may need to be changed to continue to feed molten metal into the areas that are shrinking more than others. Alan
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Cold shuts are often due to poor filling of the casting. You should be sure that there's not too much turbulance when pouring the mold. But also you have to use a clean metal or use filters. There's many sources of defects that can interact with your problem.
I suggest you to read some books about castings defects.
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