Issue Jul Aug 14
Discovering and implementing the best ways to engineer iron castings has been a continually evolving process for Elyria Foundry. The Elyria, Ohio-based company has honed its craft more than 100 years.
“We’re probably one of a handful of companies that can produce the type of complex castings we are able to create,” explains COO Henry Lee. “There is a great deal of engineering that goes into these parts.”
Founded in 1905, the company began producing castings for the machine tool and gas engine industry. Since then, Elyria Foundry has ventured into other industries, including mining and minerals processing, gas and air compression, construction, agricultural, passenger rail and general industrial applications.
In 2008, Elyria Foundry merged with Hodge Foundry in Greenville, Pa., to become “the dominant supplier of complex gray and ductile iron to the world casting market,” Lee explains. This merger enabled the firm to offer parts weighing as little as 20 pounds up to those as much as 200,000 pounds.
Hodge Foundry began in 1876 as a brass foundry. During its history, that foundry changed its production capabilities to gray iron/ductile iron and also began offering machining services. Currently, both foundries offer machining services using its network of third-party machine shops.
“Normally, Elyria Foundry casts smaller parts,” Lee explains. “Hodge Foundry handles the larger components.” For example, he notes that the company can produce thousands of pieces of a single part number annually, but also smaller quantities of job-shop production orders.
Components from the Elyria plant can range from 20 pounds to 10,000 pounds, while Hodge can accommodate castings from 3,000 pounds to 200,000 pounds.
Both facilities also practice kanban, stocking and consignment programs to ensure materials are available as clients need parts.
The Elyria site features a total of eight induction furnaces and has a total daily melt capacity of nearly 350 net tons of any grade of gray and ductile iron. The Hodge Foundry facility features 10 various sized molding pits, five continuous sand mixers and three 30-ton vertical channel induction furnaces. In addition, Hodge houses an assortment of overhead cranes that range in capacity from 10 tons up to 100 tons.
“The largest component we have manufactured was a 198,000-pound limestone grinding table for a cement manufacturing facility in Africa,” Lee notes.
One important factor that sets Elyria Foundry apart from competitors is its ability to work with very complex geometries, Lee says. “Normally, clients provide a drawing or design for a specific part, whether it’s a compressor housing or a valve,” he explains. “We engineer our own process to create the casting. Quality is very important to our clients. The parts we make must meet specific mechanical and metallurgic properties, as well as conform to the geometries the client needs.”
The manufacturing process begins with creating a design. “A customer may bring a drawing of a part it needs, or it may have part with a high failure rate or one that hasn’t been performing as needed,” Lee says. Elyria Foundry’s staff includes both mechanical and metallurgic engineers to help determine the design and proper metal chemistry to create the ideal component for a particular application.
“We’ll help with solutions on how to design the part to make it stronger, lighter or add residual strength,” he adds. “We take our people to visit customers’ plants to see our castings in actual use.”
Components are designed using CAD and other computer modeling programs. Next, a robot produces a pattern from foam, wood or polyurethane that conforms to the component’s specific geometries. “The pattern robot allows for very rapid prototyping,” Lee says.
The company also utilizes solidification software to model how the iron cools. “The cooling process can create voids that could potentially fracture and fail during the component’s use,” Lee says. “We have to account for how the iron will solidify in the mold before the casting is made.” In addition to helping engineers verify the component’s final properties, solidification simulation software helps designers determine the component design’s manufacturability as well as its estimated costs. In addition, this program helps identify and eliminate potential defects during the design stage to minimize waste and save costs.
Using quality raw materials such as pig iron, steel and alloys from reputable suppliers also is key to creating its castings. “All of our iron suppliers are certified suppliers, which means they deliver high-quality, consistent material,” Lee says. “Our lots are pre-analyzed to make sure the material meets our specifications.”
Once the metal is molten, Elyria Foundry personnel analyze the product with a spectrometer to ensure the metal is at the proper chemistry for that specific application. “We add certain alloys to the iron that will modify the component’s mechanical properties,” Lee says.
To ensure product quality, temperature and binder percentages are computer-controlled during the production process. In addition, the entire casting process is documented, including pouring times and temperatures, to ensure product consistency for each production run. The production process is frequently videotaped and samples are taken to verify the metal quality.
The final component is then tested in-house to make sure it meets the client’s demands. “We perform tensile, yield, elongation impact and hardness testing,” Lee declares. “We also carry out non-destructive testing using ultrasonic, magnetic particle and outsource radiographic testing. Dimensional testing is done with either a computerized measuring machine or 3-D laser scanner.”
Elyria Foundry’s expertise was put to the test one Monday afternoon when it received an urgent call from one of its customers. A ship’s steering gear had failed while it was at sea, crippling the vessel in the Gulf of Mexico. “The customer sent us a drawing of the part Tuesday morning,” Lee says. “By then, we were already performing preliminary pattern work.” That Thursday, the 2,525-pound finished casting arrived on the ship by helicopter. “In all, it took about three days to deliver the completed part,” Lee says.
Training is a vital part of the company’s quality initiatives.
“Both of our facilities have apprenticeship programs for our skilled trades, which include pattern making, core making or molding,” Lee says. “It takes from four to five years to achieve journeyman status and another 10 years to obtain master status.”
Apprentices also must attend classes on topics such as metallurgy, casting, and sand and binder systems.
“We also have an online web system called Iron University,” Lee notes.
Moreover, each team member must gain an understanding of the company’s entire manufacturing process, not just his or her role.
“We want our employees to understand why all of the manufacturing processes must be performed a certain way,” Lee says. “This helps them understand the theory in practice and helps them adhere to their tasks.”