Chemicals Used in Foundry Work

Metal foundries use many chemicals in the processing of metal. These chemicals are used at different stages of the formation of metal. Most of the chemicals found in a foundry exist in the mold process. Many chemicals used in the foundry are hazardous to operators' health and require special handling for safety.

Mold Process

• During the mold and core making process, the foundry uses chemical resins to harden the molds and silica dust to make the extraction of the metal from the mold. The resins use urethane (isocanate-based) resin, urea formaldehyde, phenolic resin and furan resin. All the resins irritate the skin and respiratory tract when exposed to heat.

No Bake Cores

• No bake cores, meaning molds and cores that are not heated but use the atmospheric conditions to harden, employ the following chemicals and acids: toluene-2, 4-diisocyanates (TDI) and methylene bisphenyl diisocyanates MDI), benzene, and sulfonic or phosphoric acids.

Melting and Pouring

• During the pouring of molten metal, chemicals and gases form during the process. The pouring produces dangerous levels of carbon monoxide gas. Foundries use the formaldehyde in the molds and hydrochloric acid as a catalyst, when these come in contact with molten metal, they form another chemical, bis-chlormethyl or ether.