Three years ago, ZKM Forging had no aerospace business. Nevertheless, the unit was acquired by Ladish to capitalize on emerging aerospace opportunities triggered by rising international demand for high-quality structural parts and for more fuel-efficient and environmentally friendly aircraft engine components.

At the time of its acquisition, ZKM had a 22-year reputation as one of Poland’s largest and best general industrial-forge shops. Ladish wanted to build on this reputation and add aerospace categories to the dozen other major industry segments ZKM already served. To participate in European-based aerospace supply chains, ZKM’s new parent launched a program focused on the installation of an array of high-tech business systems and capabilities designed to satisfy the exacting standards of aerospace production. Within the past two years, this plan has been largely executed, and aerospace orders have begun flowing in. What follows is a glimpse of what ZKM Forging did to leap into the Central European aerospace forging market.

Figure 1. The company’s IT system ensures that customer requirements are integrated into its process.

FORGING AND DIE DESIGN

To offer aerospace customers competitive levels of capability and service, ZKM committed itself to the acquisition of support technologies, systems and training necessary to design and manufacture forgings based on customer finish-machine prints. The company acquired industry-specific CAD/CAM software (such as CATIA), trained its design department in its use and began working with an array of international aerospace OEMs and first-tier suppliers based in Poland, Europe and North America to successfully bid on and receive aerospace orders.

Investments started in the engineering department. To ensure a seamless and paperless flow of information from ZKM’s die- and forging-design engineers through the entire factory, the company installed a plant-wide IT capability. The system, which is the same as the IT system in use throughout Ladish’s U.S. business units, ensures data accuracy and traceability throughout all of ZKM’s operations.

The ERP features of this IT system help ZKM make sure customer requirements are fully and precisely integrated into its process. As a result, the entire plant can be managed for optimal performance. At every phase, original customer-data files support the forging process as well as post-forging machining, finishing and inspection operations. Using this system, ZKM is able to function as a supply-chain link with other Ladish operations or with other suppliers and OEMs in global supply networks.

Figure 2. The die-making department installed new CNC machine tools to improve die lead time.

DIE MANUFACTURING

Customers have intensified demands for integrated support and the fastest possible new-product development and manufacturing turn times. In response to the need for speed, ZKM reorganized its existing in-house die-manufacturing area to optimize the operation of this 8,000-square-meter department. The department installed new CNC machine tools to improve die-manufacturing lead time and eliminate the possibilities of human error. The die-making area has also added new optical equipment for precision.

Improvements extended beyond die making. For example, to enable fast die changeover and rapid manufacturing, ZKM has dedicated 1,000 square meters of plant space to its fully automated die storage and retrieval area – the largest in Central Europe. Here, more than 2,000 individual dies are stored for service. Their setups and teardowns, retrievals and replacements are tightly synchronized with the manufacturing schedule to maximize the orderly flow of dies and minimize queue-and-wait time in the forge shop.

ZKM produces all the dies and tooling used to manufacture forgings for all the markets it serves in its plant in Stalowa Wola, Poland. Moreover, the rate of die production is growing. The company produced 25% more dies in 2007 than it produced in 2006, and the operation expects to produce 33% more dies in 2008 than in 2007. To support this growth, two new, fully automated CNC machines arrived in October and November of 2007 and are scheduled to be in operation by the end of 2007 or early first quarter of 2008.

MATERIAL PREPARATION

The raw-material-stores department was another target for upgrades. Enhancements in this area were also designed to facilitate synchronizing production and minimizing queue-and-wait time. Historically, this area had the capability to prepare any material to meet any customer’s input specifications. All materials that required preparation of any type were processed in this department. Management’s intent was to expand this capability to aerospace materials as well.

To prepare the company to handle new aerospace work while concurrently improving flow for existing general industrial forgings, the raw-material-stores department added new cutting equipment. The new band saws now prepare all forging material used in the plant. They provide faster, more accurate cutting than the older equipment. These capabilities help ZKM maximize raw-material usage while assisting throughput-improvement initiatives and reducing disruptions to plant-wide production. ZKM has the resources to cut materials in stock sizes up to 400mm. The shop also has a range of other resources – such as shot-blast and grit-blast machines as well as other tools – to meet the specifications of aerospace customers.

Figure 3. ZKM has 10 single-acting hammers and a counter-blow hammer.

FORGING HAMMERS

ZKM has 10 single-acting hammers rated from 1-10 metric tons as well as a Beche counter-blow hammer rated at 50,000mkg. Two of the larger hammers have recently been rebuilt with new rams. ZKM’s hammers can accommodate weights up 300kg (660 lbs.), lengths up to 1,200mm (48 inches) and diameters up to 450mm (18 inches).

These hammers are currently supported by rotary- and box-type forge-shop furnaces. Although many of these furnaces can meet aerospace heating requirements, management’s intent is to upgrade the combustion systems for a number of them during 2008 in order to reduce energy requirements and ensure the availability of sufficient capacity. In addition, the company is adding new furnaces designed to more efficiently serve the smaller quantities common with aerospace orders. To support the operation’s cellular-manufacturing strategy, an additional furnace will be co-located with the Beche counter-blow hammer.

Figure 4. The company has 10 forging presses to complement its hammers.

FORGING PRESSES

Complementing the installed base of hammers is an equal number of presses. The facility boasts a dozen presses ranging in capabilities from 1,000-4,000 tons. These offer capabilities that are reportedly unavailable elsewhere in Central Europe. In fact, ZKM’s ability to produce forging preforms surpasses that of its sister operation in the U.S. At ZKM, preforms are manufactured using the plant’s upset and roll-forming capability, which offers a more economical means to produce certain types of aerospace parts.

Additionally, the operation’s Lasco press has a unique “hard-blow” capability that allows it to produce parts with greater definition than can be achieved on conventional hydraulic presses. Upgraded with new hydraulics in 2007, the Lasco press can accommodate weights in the range of 5-55kg (120 lbs.), lengths up to 1,000mm (40 inches) and diameters up to 280mm (11 inches).

To enhance the ability of the hammers and presses to provide responsive manufacturing based on customer delivery schedules, the shop invested in auxiliary equipment – such as new manipulators – that keeps parts moving quickly through the process. This combination of a lean-manufacturing approach, targeted upgrades and investments in auxiliary equipment, training and quality systems allows customers to take full advantage of the mix and breadth of ZKM’s press and hammer resources to meet build schedules.

Figure 5. The company does much of its own thermal treatment on finished parts.

HEAT TREATING

Regarding its thermal-processing capabilities, the company upgraded numerous furnace and process controls to assist the operation in meeting its aerospace certification requirements. The shop now has four electric heat-treat lines that can supply continuous processing through all the high- and low- temperature heat-treat cycles typical of aerospace alloys. The capabilities of the heat-treat area have been enhanced with a recent upgrade to the aerospace AMS2750 certification level.

Augmenting the capabilities of its continuous furnaces, the shop also maintains a box-furnace cell, which is also being upgraded to satisfy aerospace requirements. When these upgrades are completed, this cell will have four electric-box furnaces with both oil- and water-quench capabilities available. All these furnaces have been upgraded to meet the specific heating- and quench-rate technical requirements for steel, titanium and other aerospace alloys.

Figure 6. A finished part undergoes dimensional inspection with the help of a new coordinate measuring machine (CMM).

NONDESTRUCTIVE TESTING (NDT)

Superior NDT capabilities are a prerequisite for becoming an aerospace supplier. To meet expectations for nondestructive testing, the company installed a Magnetic Particle Inspection (MPI) unit to perform post-forging evaluations. To provide this range of services, the forge’s MPI capability had to be supported with Level III Certification. During June 2007, the company’s first inspector completed this training, becoming qualified under the top aerospace standards – EN4179 and NAS 410.

According to Jack Franczak, Ladish’s director of quality and technology for European operations, “A key part of ZKM’s new business strategy is to make sure that a population of highly trained professionals grows to keep pace with the installation of new inspection equipment and other quality-control-related capabilities. For this reason, a substantial percentage of investments in machinery, computer hardware, software systems and quality systems are accompanied by investments for the training of personnel in their use. For example, in addition to the company’s Level III certification, personnel are also pursuing NADCAP approvals in the area of inspection and heat treating, which are expected to be awarded when the shop completes its final audit early in 2008.”

Expanding inspections further, a new CMM station to provide dimensional inspections was installed. This investment was made not only to meet customer requirements for this type of inspection but also to support expanding internal quality-control demands.

THE LAB

The facility maintains a metallurgical laboratory capable of performing chemical, microstructural, room-temperature mechanical, and other types of destructive and nondestructive testing. The lab meets a wide range of standards for general industrial forgings, but it subcontracts aerospace testing at present. The lab has upgraded its capabilities with a new tensile-test machine that meets aerospace standards and plans additional investments in the future.

QUALITY CERTIFICATIONS

ZKM has long had a culture of quality. The shop’s established quality system is based on QS 9000. In addition, the company maintains a suite of quality certifications, including ISO 9001:2000, ISO/TS 16494:2002 and AS9100:2004. Because of the strength of the company’s quality system, the installation of enhancements that would facilitate the transition into forging aerospace components has proceeded relatively quickly.

FINISH MACHINING

Last August, the company announced a physical expansion to respond to customer requests for finish-machining services. Recognizing that these capabilities are essential for supporting future work from first-tier suppliers and OEMs, the company plans to place new equipment and personnel in an existing facility adjacent to the forging plant in Stalowa Wola. In the interim, the machining of components with immediate requirements is subcontracted to nearby suppliers.

ZKM is attempting to establish itself as a one-stop shop of integrated capabilities to meet aerospace production requirements for all aerospace alloys. According to Ray Knutilla, Ladish’s managing director of European operations, “Ladish has planned its investments to ensure that ZKM will be able to participate in multiple segments of the aerospace market no matter what specific demand may emerge for different types of components, materials and applications. We have strategized an approach to investment and production that will allow us to move quickly in whatever direction our customers need us to.”