The Ladish Co. Inc.

Citation

(1999), "The Ladish Co. Inc.", Aircraft Engineering and Aerospace Technology, Vol. 71 No. 5. https://doi.org/10.1108/aeat.1999.12771eaf.003

The Ladish Co. Inc.

The Ladish Co. Inc.

Keywords: Ladish, Aerospace, Forging

The Ladish Co. Inc. is a manufacturer of technically advanced forging. Headquartered in Cudahy, Wisconsin, USA, the company has operations in Wisconsin and Connecticut. Sales of more than US$220 million in 1998 reportedly made Ladish the second largest forging company in North America. Approximately 50 per cent of the firm's sales volume is to customers outside the USA, and close to 90 per cent of its production is sold to aerospace manufacturers. The 94-year-old company began public trading of its stock in 1998.

Ladish supplies the global aerospace industry with a wide range of rotating quality and structural forging. For example, it claims to be the world's largest provider of turbine discs for the hot sections of jet engines, as well as the sole source for many of the industry's largest, most technically advanced forging, particularly large, thin-walled seamless rings, domes, and cylinders.

At the heart of Ladish's capability is a collection of one-of-a-kind production resources that enables the company to supply customers from one location. These resources include: a 15,000-ton press that is able to forge the largest aerospace components currently being designed; a 1,200-ton ring roll mill, believed to be the world's largest; a 10,000-ton sizing press, also considered the world's largest; and the world's largest shear-forming facility. These resources have helped the company secure a reputation for producing large, complex, highly engineered components made from difficult-to-forge materials.

15,000-ton press

The configuration of Ladish's 15,000-ton press allows aerospace designers to forge the largest components in production. This press features a 90-inch stroke, 207 inches of daylight and 188 inches of usable space between the columns (see Plate 1). The press is used to convert ingot or billet material of all alloy types into the desired shape needed for subsequent processing. This is accomplished via forming, piercing, pancaking or extruding operations, which in many cases can be accomplished without the need for sophisticated special tooling. Parts as large as 95 inches tall, or 188 inches in diameter can be produced. In addition, two 4,000-ton side rams allow for three-way forming operations.

Plate 1 15,000 ton press

In May 1998, Ladish completed an upgrade to this 15,000-ton hydraulic press. The upgrade included the installation of a new ram with quick-tool-change capabilities, a complete rebuild of the computerised hydraulic cylinders and hydraulic power systems, and the incorporation of computerised controls. The control system was designed to provide multiple benefits, such as improving the speed and accuracy of press operations, while conserving energy and controlling costs during the forging cycle.

The 15,000-ton press is currently being used to preform and extrude large ingots or billets that are further processed by Ladish to manufacture titanium and aluminium jet engine fan cases, VAR steel solid rocket motor components for such programs as the space shuttle RSRM and Ariane 5, as well as large aluminium rings for fuel tank and structural applications for launch vehicles, including the EELV, Kl, H2A, and X33. Ladish has expertise working with the full range of aerospace metals such as high-alloy steels, aluminium, aluminium lithium and titanium. Once a desired shape has been press forged, it is further processed on one or more of the following resources.

1,200-ton ring roll mill

Ladish believes that it maintains the largest ring roll mill in the world. This resource has the capability of producing seamless ring and cylinder shapes weighing up to 350,000lb, with a maximum diameter of 336 inches and a maximum face height of 120 inches. This production unit also has the capability to forge components with integrally rolled contours, adding strength and reducing the input weight and costs. These circumferential contours can be maintained over the course of all subsequent operations (see Plate 2).

Plate 2 Ring roll mill

This piece of equipment is key to many space vehicle programs. Without it, many components simply could not be produced in their existing configurations because there are no alternative production resources of equal capability. In fact, a number of launch vehicle components were designed around Ladish's resources and capabilities, many of which are the largest of their type. The company is currently producing large cylinders for the Space Shuttle and Ariane 5 launchers (see Plate 3). The highest volume of Ladish's launch vehicle production today is made up of seamless aluminium rings for the commercial launch vehicle industry, as well as seamless thin-walled titanium cylinders for jet engine fan cases and copper circuit foil production equipment.

Plate 3 Thin-walled cylinder

The company has a long history of serving aerospace, providing components for solid- and liquid-fueled motors and satellite-fuel-tank applications since the industry's inception. A case in point is Ladish's patented D6AC alloy, which was chosen in 1958 for use on MinuteMan forward and aft domes and cylinders. Ladish engineers also developed a process for forging the pure tungsten nozzle throats and pure molybdenum nozzle housings, for which the company continues to be the sole source.

Typically, manufacturers turn to Ladish for big complex shaped parts such as the aft dome of the Titan IV launch vehicle shown in Plate 4. Launch vehicle developers seeking the largest, seamless aluminium rings for components such as liquid fuel tanks have no other source for such components. In addition to simple ring and cylinder shapes, the company routinely produces tapered and cone-shaped components using a variety of high-alloy steels, aluminium and titanium.

Plate 4 Aft dome

10,000-ton sizing press

The world's largest ring roll mill is complemented by a 10,000-ton sizing press, also considered by Ladish to be the world's largest. This press is capable of hot or cold expansion to diameters up to 300 inches and face heights up to 200 inches. This equipment provides critical diameter control for large rings. This press is unmatched in its size capabilities for the cold expansion process for aluminium rings, enabling these components to meet the aerospace industry's most stringent heat treatment requirements.

Shear forming

The company has the capability to perform a process called shear forming, which is a forming operation that transforms a seamless rough machined cylinder into a net, thin-walled component by simultaneously thinning and stretching the membrane wall while at room temperature. Net walls of 0.375 inch are typical. Cylinders processed by Ladish achieve net-wall tolerances of plus or minus 0.010 inch, with no subsequent machining required. This thin-wall capability enables aerospace designers to utilise fewer components in their designs, minimising or eliminating the need for costly welds. In addition, because the cylinders are delivered in near-net shape, there are significantly fewer machining requirements prior to final assembly.

The Ladish shear forming process is responsive to manufacturers' needs for reduced production costs and lead times, because it substantially reduces the initial raw material input weight requirements, and minimises the amount of rough and final machining, welding, and associated inspections. The company's shear forming capability can produce seamless components up to 174 inches in diameter and 200 inches in face height, with wall thickness capabilities approaching 0.250 þ 0.010 inches.

Ladish's shear forming equipment is unique (see Plate 5). It permits aerospace manufacturers to specify the highest level of control in the industry for producing the largest, seamless, thin-walled cylinders available anywhere.

Plate 5 Shear forming

Fully integrated heat treat facility

Once the domes, cylinders and rings have completed all of their forming operations, Ladish employs additional resources to finish the workpiece. The company maintains furnaces capable of handling components up to 336 inches in diameter and 168 inches in height. In addition, the company has a 120,000-gallon water quench tank with agitation capabilities. This tank can handle work pieces up to 372 inches in diameter and 200 inches in face height. Ladish's oil quench tank is 312 inches square and 200 inches deep. Like the water tank, the oil quench tank also has agitation capability. With this equipment, Ladish maintains the capability to perform final heat treatment on carbon steel, VAR structural alloys, nickel-base and stainless, and aluminium, as well as stress relief or annealing operations for components made of titanium.

Rough machining and NDT

To enable Ladish to supply fully qualified and tested components, their facility includes manual and CNC turning equipment capable of machining diameters up to 336 inches and face heights up to 240 inches. In addition, these resources are equipped with manual and CNC boring bars for complex milling operations. Most components are supplied in a heat-treated and rough-machined condition, and NDT inspected via ultrasonic and/or surface penetrant when required. This allows the customer to procure components fully processed and ready for final machining and assembly. This one-stop shopping simplifies the customer's procurement responsibilities, and allows for higher quality, in part because this approach eliminates the multiple liability issues that result from a part-acquisition process that involves multiple subcontractors.

In summary, Ladish maintains a fully integrated shop, capable of producing some of the largest, most highly engineered, fully qualified products available to the aerospace industry. From jet engine rotating components and fan cases, to solid rocket motor segments and liquid fuel structural rings, Ladish utilises unique equipment capabilities, supported by a large staff of in-house metallurgical and engineering personnel, to develop manufacturing solutions to the aviation and aerospace industry's largest, most highly technical programs.

Beginning with the Minuteman program in 1958 and proceeding though the Titan III/IV, Space Shuttle systems and the largest commercial launchers being designed today, Ladish one-of-a-kind capabilities and expertise have provided key contributions to the development and success of key aviation and aerospace programs. The company attributes its growth (international sales have increased 300 per cent over the last three years) in the current strong economy to its maintenance of a ''one-stop shopping'' forging capability and high-quality standards (the company is ISO 9002-certified). This business strategy has enabled Ladish to provide cost-effective, high-quality solutions to the industry's most demanding problems.

Further details are available from Ladish Co. Inc. Tel: + 1 414 747 2611; Website: www.ladishco.com or www.forging.com