TPT November 2007

Technology Update

Delivery of complete directube ® plant

The upper and lower tolerance limits permit detection of excessive pull force or a loss of pull force on the mandrel rod during each bend cycle, indicating process variation that can lead to mandrel failure or production quality issues. These can result from loss of lubrication, weld seam imperfections, galling of the mandrel, wiper die wear, the mandrel position being out of adjustment, excessive tool wear or loss of mandrel integrity. The system can also detect excessive compression force during mandrel advance to prevent bending the mandrel rod if there is an insertion jam. The new PVM2000-MB release B offers a simplified Learn cycle through simple integration of the monitor with the bender’s operating system. Following a single process cycle, the mandrel bend monitor automatically goes to Run mode and alerts the operator to process variance that can lead to a problem, helping to protect tooling, reducing downtime, and assisting with set- up verification. The system enhances error proofing of the bend process by isolating product if a mandrel link breaks.

Copper tube producer, KobeWieland Copper Products (KWCP), USA, has placed an order with SMS Meer, Germany, for the supply of a complete plant for the production of mother tubes. The new directube ® line is to be installed at the company’s plant in Pine Hall, North Carolina, and is scheduled for commissioning at the end of 2008. In addition to the complete equipment for the plant with cathode charging facilities, melting and casting plant through to the planetary rolling mill (PSW), SMS Meer will supply the electrical open-loop and closed-loop control technology and ancillary facilities. The scope of supplies and services also includes commissioning of the plant and training of the company’s personnel. The order for the directube ® line forms part of a major investment programme with which KWCP (a joint venture between Kobe Steel, Japan, and Wieland-Werke, Germany) aims to further increase its competitiveness and expand its existing production capacity. With a tube weight of 1,100kg, the directube ® line in Pine Hall will be modern and efficient, and an important reference plant for SMS Meer. Themother tubes produced on the directube ® line will be made of DHP copper. On the planetary rolling mill, they will be reduced to Currently, HF weld quality is achieved through careful and repeatable welding practices. Operator knowhow and experimental knowledge have become a foundation upon which tube and pipe companies find their success. Unfortunately, any minor changes in speed, setup, or material can be a variable which has an affect on the weld. Companies are quick to ramp up welder power or fall back on mill setups that are known to provide an acceptable product. High frequency welding is surprisingly forgiving and while these adjustments are often satisfactory they are rarely ideal. Improving control of the HF weld itself can

› Comparison between a conventional seamless tube process and directube ®

a diameter of approximately 60mm, with a wall thickness of approximately 3mm. They will be further processed by KWCP. The finished tubes, in a diameter range between 12.7mm and 7mm and with a wall thickness of approximately 0.3mm, will be employed predominantly in heat exchangers. Features of the plant include the use of a pressure controlled casting furnace that ensures a constant high quality and high yield of the cast mother tubes and the operation of a continuous planetary rolling mill of the latest generation with a significantly enhanced production capacity.

SMS Meer GmbH – Germany Fax : +49 2161 350 667 Email : info@sms-meer.com Website : www.sms-meer.de

Advances in HF welding – heat affected zone

› The PVM2000-MB mandrel bend monitor from OES, Inc

lead to more consistent weld strength and a higher quality end product. The first true variable frequency HF welders went into operation in 2003. New technology at the time, it proved to many tube producers that 1) frequency is a key process parameter that should be selected for a particular product set-ups, and 2) each welding process has a ‘best weld’ point, where power and frequency are optimally balanced, with other mill variables. A mathematical model has been developed to provide insight into making the ‘best weld.’ Increasing the operator’s control over the welded seam will help maintain the best weld for demanding applications.

The PVM2000-MB provides two levels of alert to process variations, and offers both audible and visual alarm options to indicate failure conditions to the machine operator. Integrating the Fail output to machine control can stop the bend cycle before further damage occurs. The system features a user-friendly touch screen interface display for monitoring, configuration and threshold adjustment. With updated BendView™ companion software, the entire bend process can be captured in real-time, and each bend in a production run can be logged to a computer file for analysis and traceability.

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OES, Inc – Canada Fax : +1 519 652 3795

Email : oes@oes-inc.com Website : www.oes-inc.com

€ Maintaining control over the weld seam

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N ovember /D ecember 2007