Nobake Solves a Size Challenge
Victaulic’s long-term plan to produce large iron castings culminated in its first nobake molding line at a new site in Mexico.
A MODERN CASTING Staff Report
(Click here to see the story as it appears in July's Modern Casting.)
When the first large castings ran off the line at Easton, Pa.-based Victaulic’s new foundry in Chihuahua, Mexico, it was the culmination of a lengthy process of planning and development. With casting plants already established in China, Poland and the U.S., the metalcaster sought to expand on its principles of local production, global reach and thorough quality control.
Constructed from scratch on a greenfield site, the new plant supplements Victaulic’s global capabilities and enables a wider range of casting and finishing services than the company has been able to offer before. Its distinguishing feature is the large-casting, nobake mold operation, which is unique within the company. With capability to pour ductile iron grades 65-45-12 and 80-55-06 at a maximum casting yield of 3,000 lbs. (1,360 kg) and up to 72 in. diameter (1,825 mm), a limited number of metalcasters compete with it on size.
Completed by 2012 and now in full operation, their facility serves a growing market. The Chihuahua site, built in a brand new industrial park, benefits from favorable economic conditions and a pool of skilled local manufacturing labor.
“The site offers a major extension of our capabilities,” said Didier Vassal, vice president, Victaulic. “It is in no way a replacement for our existing U.S. offerings, or anywhere else in the world, but is part of a new, bigger global plan.”
Looking ahead at likely demand, principally in the North and South American markets, large valve parts, vehicle parts, pump and compressor housings, and a wide range of specialized castings are projected to be the most commonly manufactured products at Chihuahua.
“Offering ductile and gray iron in these very large castings, with up to 10 molds per hour, is a somewhat unique proposition,” said Vassal. “Customers want the same standards they have come to expect from all our global operations, and our new capabilities and capacity mean that we can now offer this with large castings. Clients have previously found these sizes problematic to source.”
Location, Location, Location
The need to find the best-positioned site led Victaulic to Chihuahua, which is less than 240 miles (400 km) from the U.S. border near El Paso, Texas. The site necessitated a fairly unique set of precautions. Storms, high winds and hurricanes present a threat, and while the site is in a desert at 4,900 ft. (1,500m) where rain is not the norm, storm drainage is vital. Also, due to the dry local climate, the soil required modification to compact adequately before construction could begin.
“We are talking about more than two years of high-level planning,” said Wayne Holmberg, manager of facilities engineering, Victaulic. “We reviewed a great number of design iterations before selecting the best one. We wanted to exceed customer requirements and reduce the time it took to build, while also conforming to codes, facility maintenance approvals and demanding international standards.”
Holmberg was among a group of technical experts, engineers and foundry consultants who were heavily involved in the planning, construction and start-up, working to ensure every step of the design process went smoothly and according to plan.
Choosing to construct the high-tech facility on a brand new site allowed Victaulic to tailor the casting facility toward optimal operations and provide for future expansion.
“We have 90-plus years of history at Victaulic and the company certainly understands the foundry industry inside out,” said Holmberg. “But we made sure we brought in the right experts to assist us in the setup of all areas, and that made a big difference.”
Victaulic chose to add its own electric substation to supply power, as it has done before with other facilities, even those situated in industrial parks.
The new plant’s molding process was adopted for advantages such as surface finish. This line features fast loop, roll-over, flow coat, semi-automated molding with a 79 x 84 x 71-in. maximum fast-loop mold capacity. The core room also uses a nobake process and a flow coat system.
Nobake molding is the perfect molding process for large and heavy castings, according to Vassal. It provides high dimensional stability and can reach up to 0.01 in. (0.254mm) ofprecision before machining in non-core/parting line areas.
On the melt deck, two induction midfrequency furnaces of three metric tons each have treatment and pouring ladles of 1.5 metric tons.
The most common parts manufactured on a daily basis are large pipe fittings and accessories, pump and compressor housings and large valve parts.
The new facility in Mexico is one of the company’s most energy efficient and clean plants. Sand is thermally reclaimed, and 90% of product is made from recycled metal. It also employs advanced painting techniques to lessen the effects of volatile organic compounds. Dust cleaners improve working conditions and reduce environmental impact.
“We are addressing our global sustainability commitments, and customers are increasingly aware of our efforts,” said Vassal. “We have taken a number of very positive steps. For example, we now have an environmental manager solely concentrating on better dust extraction at our facilities worldwide.”
Quality Is Essential
With a dedicated department responsible for ensuring high standards are consistently enforced worldwide, quality control is central to Victaulic. The company employs a director of global quality and process technology who organizes regular audits and arranges seminars. Best practices are disseminated throughout its operations and knowledge is exchanged, making sure the right people are in place to oversee production standards at any given time.
“Quality is key for our customers, and it is key for us,” said Vassal. “We aim for consistently outstanding levels of customer service.”
The new plant uses vertical turret lathes, which “attack” a rotating part with fixed cutting tools to meet tough upper-end specifications and maintain high quality levels. Horizontal boring mills with rotating cutting tools tackle stationary parts.
“The foundry moved very smoothly into production, and the design team moved on to the next challenge,” said Vassal. “For Victaulic, this is another exciting and major step forward in the company’s history.”