Mill-Pac Gray

Mill-Pac Gray at IGS Industries

Mill-Pac Gray is an organically bound, non-toxic paste sealant that was originally developed for use in sealing foundry molds to floors or stools, or for sealing stress cracks or bad joints in molds. It has also found use in sealing boiler and oven doors, as well as sealing burners. Mill-Pac Gray will not handle any pressure, but its high temperature rating and low cost makes it a sealant of choice.

Mill-Pac Gray will stay soft until heat is applied. Once cured, it takes on a leathery-like consistency. Sealant is not an adhesive and must be held in place by the joint which is being sealed.

Typical Applications

  • Sealing argon gas in molds

  • Sealing open-bottom molds to reduce steel loss

  • Sealing cope and drag foundry molds

  • Sealing hot tops and stress cracks in molds

  • Sealing boiler and oven doors

  • Burner sealant


  • Non-toxic formulation

  • Inexpensive
  • Easy application and clean up
  • Expands with heat to provide a good seal
  • Resists molten metals

  • Mill-Pac Gray is not classified as a hazardous material and is able to be shipped worldwide by any means
  • Mill-Pac Gray is available through our Just-In-Time shipping program


mill-pac gray

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