Foundry facings

Anthracite Anthracite is harder to reduce than bituminous coal. It is pulverized for foundry-facing mixtures in baU mills or hammer mihs fohowed by air classifiers. Only to a lesser extent is it used for fuel in powdered form. 

M. LaPedus. Foundries face obstacle course in 45 nm race. EE Times Asia, May, 2007, http //www.eetasia.com/ART 8800464631 480100 NT d25bb9ea.HTM. 

Colloidal silica was used in general foundry applications such as gunning mixes, ceramic mold facings for core boxes and the like, mold washes, and semi-permanent molds with renewable facings. It was also used in the production of wallboard (Figure 4). 

Cereal binders Starch and dextrin are used mainly in steel foundries to avoid defects caused by silica expansion and to control moisture excess in the sand mix. Effective additions of cereal binders to new green sand facing mixes are between 0.5 and 0.75 %. In unit type green sands, part of the cereal is destroyed during the casting process. The recommended addition on each recycle is 0.1 to 0.25 %, depending on the amount of cereal burn-out and on the dilution by cores and new sand. 

Suprasec 1042 Suprasec 1249 Suprasec DND Suprasec DNR Hexacal F Hexacal SN Hexacal LN 2-7 Low viscosity polymeric MDI. Low density rigid foams. Semi-rigid foams. Isocyanurate foams. Particle binders. Insulating foams. Energy absorbing foams. Isocyanurate foam building panels. Mine-face consolidation. Chipboard and foundry sand binders. 

Graphite Foundry molds facing (70%), crucibles, and lubricant. 

In this case, it was determined that the corrosion reactions were those normally expected in a ferrous foundry, i.e., chemical solution of the bond phase of the brick with penetration behind the hot face. Large veins of solidified metal were found within the used brick, indicating mechanical failure in service followed by metal penetration. 

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