St. Marys Foundry Inc. is installing a new 174-foot x 182-foot oven in an effort to increase its in-house heat-treating capacity. The metal-casting company in St. Marys, Ohio, expects to heat treat 60-70% of its castings in the oven, which it hopes to have operational by mid-December. St. Marys Foundry, which produces approximately 1.2 million pounds of castings per month, has a goal of eventually performing all heat-treating services in-house.