A 5,000-lb machine returns to valuable service
In 1977, Modern Drop Forge decided to expand its operations, selecting a site near Johnson City, TN, because of its available labor force, low energy costs thanks to the Tennessee Valley Authority, and its proximity to both an excellent road system, and its customers.
The following spring, Modern Forge Tennessee began operations. The plant would supply quality forgings to the railroad, mining, motorcycle, aerospace, recreational vehicle, aftermarket automotive, and agricultural market segments.
At the beginning, MFT was supplied with Chambersburg Equipment Co.’s CECO-Drop hammers, which grew to a total of 11 units, ranging from 2,000 to 4,000 lb.
In 1989, responding to customer needs for larger forgings, Modern Forge Tennessee decided to purchase a newly designed Power Forger from Chambersburg Engineering Co. since it was determined to be the most modern design available and provided much increased forging capacity.
The hammer performed as advertised, but was not sufficiently reliable in production. So, in 1992, the hammer was replaced with a 5,000-lb double-acting hammer transferred from another plant. The Power Forger was returned to the original manufacturer, and remained there until 2002.
After considerable deliberation, Modern Forge Tennessee general manager Mark Schwartz bought the remains of the hammer that year in an auction, with the intent of placing it in service after design and control improvements.
Meanwhile, Chambersburg Equipment Co. was purchased by Ajax Manufacturing of Cleveland, after it ceased operations and liquidated its plant and equipment. Former employees of the original Chambersburg group joined the Ajax group to form a new company, known as CECO.
The new manifestation of CECO manufactures programmable die forgers and power forgers as complete new machines, or as conversions of existing manual machines. The company also converts automated impacter systems and provides repair parts and technical service for the full line of Chambersburg’s hammers and presses.
Back at Modern Forge, while the 5,000-lb hammer machine remained in storage, specifications and design improvements were decided, and CECO began modifications in the third quarter of 2004. An analysis of the original design revealed that a number of areas required improvement, including the anvil ratio, energy capacity, control valve location, valve design, blow-rate control, control configuration, and foundation system. It was also decided that the combination of the valve opening and timing should be such that the machine could not overstrike, even if some control malfunction should occur.
The anvil chosen was a used and modified anvil from an 8,000-lb double-acting hammer. Control valves were placed atop the crown (cylinder). Lifting air volume was increased and lifting air pre-fill bypass was added to speed up preparations for forging.
Controls were designed around an Allen Bradley PLC with 10-in. HMI, with specialized programming that enabled operators and supervisors to set-up operating programs and have troubleshooting and diagnostics readily available.
A separate operator control console contained all of the necessary inputs, outputs, and necessary adjustments for lifting air pressure and to allow the operator to quickly and easily observe the hammer’s operation and air pressures, and to be able to shut it down quickly if necessary. A Vibro-Dynamics elastomeric foundation system was used.
The revamped Power Forger was installed and began production in January 2005, thus beginning its second life as a part of the production team at Modern Forge Tennessee, finally putting the 5,000-lb double-acting hammer into retirement.
Rising above the other hammers on the line, the No. 40 Power Forger takes it place as a critical element of the production process at Modern Forge Tennessee. It brought programmability, better guiding, versatility, consistency, and ease of use to Modern Forge as the company worked to improve productivity and deliver better quality to its customers.
In the months that followed, the hammer has been operated on three shifts and has "made everything put between its dies," says Schwartz. It has operated without any problems.
"We are very pleased with the results," he added. "The Power Forger has allowed us to make larger parts and make them at a higher level of quality than we were able to achieve before."