TPT September 2014

Article

Caparo

The resulting current crowding is termed as the proximity effect. This crowding gives an increase in the effective resistance of the circuit, which increases with frequency. If the edges are not parallel to each other, and if there is a mismatch defect present in the tubes, the proximity effect and the skin effect will not work as desired. This will effectively change the resistance of the tube, along with the distribution graph, leading to highly potential chances of “cold weld” or “paste weld” as the defect is known in the common parlance of tube industries. 4 Acknowledgment We thankfully acknowledge the staff and associates of Caparo Engineering India Limited, Tube division, Dewas, India, for their support and cooperation. We also thank Mr Siddharth Mittal, GM, marketing, CEIL, Dewas, without the support of whom this work could not have seen its dawn. 5 References a. Roll Forming Handbook (edited by George T. Halmos), 2006 b. Common HF welding defects, Robert K Nichols, PE, Thermatool Corp c. http://en.wikipedia.org/wiki/Chuck_(engineering)#Self-centering d. Optimizing Efficiency in HF Tube Welding Processes, John Wright, Electronic Heating Equipment, Inc

Caparo – Information Caparo is a diversified global association of businesses with over €1.5bn turnover. With interests predominantly in the design, manufacture and marketing of value added steel and niche engineering products, Caparo’s wider activities also encompass new product development, materials testing services, hotels, media, furniture and interior design, financial services, energy, medical products and private equity investment. The group was founded in 1968 by Indian-born British industrialist, the Rt Hon Lord Paul of Marylebone, who remains chairman. Today, Caparo and its associates employ more than 10,000 people in their worldwide operations across Europe, North America and Asia (including the Middle and Far East).

Caparo – India Number 46, Near Chennai Trade Centre, Mount Poonamallee Road, Chennai, TN 600089, India Website: www.caparo.com

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September 2014