TPT May 2009

T echnology U pdate

Advanced generation of induction bending machines for heavy pipes

AWS GmbH, Germany, is the manufacturer of machines and equipment for the mechanical forming of pipe for power stations, shipbuilding, and oil and gas production industry. The company’s new series of SRMBI induction bending machines are designed for pipe bending of high-performance and high- strength materials. Induction bending involves the heating of a pipe made from austenitic or ferritic steel by the means of a medium frequency inductor, to a temperature at which the yield strength of the material to be formed is greatly reduced, allowing the pre-determined geometry of the pipe to be formed. The objective of the bending process is to produce pipe bend sections which maintain absolute minimal wall thinning on the exterior of the bend, as well as producing a cross sectional form with acceptable ovality tolerances, and producing the desired geometrical form with respect to radii and angular requirements. Require- ments for bent pipes, in particular in the energy producing industry, are becoming increasingly stringent. When producing steam lines, super-heaters and manifolds, the majority of power plant manufacturers have already initiated the replacement of conventional materials such as P22 with high performance materials like P92 or Alloy 600. Due to their chemical composition (high quality chrome/nickel/ molybdenum alloys), pipes made from high-performance materials have a higher long-time rupture strength, pressure resis- tance and corrosion resistance, and can be used under operational conditions of up to 750°C, with minimal loss of their mechanical properties. In pipe production, the high mechanical properties and strength of the new materials have a high material saving potential. As a result, the wall thickness of a P92 pipe can be reduced by 60 per cent compared to pipe made from conventional materials. The manipulation and forming of pipe made from high-performance material with high material strength, at the same time having reduced wall thickness, is a new challenge for experienced plant and machine manufacturers. AWS Schäfer’s new SRMBI models offer a solution with powerful hydraulic drives, and produce bends with high precision and quality, whether pipe Schäfer Technologie

from high-performance materials or low allowed steels are being employed. The machines can perform three- dimensional bends, as well as bends with tight radii of 1.4 x D, with wall thinning of maximum 12.5 per cent the original material thickness at the exterior of the bend. Bends forms of up to 182° at tight bending R/D ratios and ovality tolerances, which do not require re-work with additional equipment, offer a time and cost saving in comparison with conventional machines. Depending on the pipe diameter, radii to be bent, and material and thickness, various trapezoidal forces occur throughout the bending process that are capable of causing changes to take place in machine position. The can result in deviations from the desired bending geometry. The new machines are equipped as standard with a newly designed braking technique, developed in-house by AWS Schäfer. In combination with the robust structure with hydraulic feeding force, which can be set with variable speed, position and force, the SRMBI series ensures perfect positioning precision, with the correct feeding force at the required speed, even when working on the heaviest of pipe work pieces. The machine design enables precise bending of the most popular pipe dimensions (diameters from 50 to 1,660mm, and wall thicknesses from 3 to 120mm), making the machines suitable for use in many different industrial fields. The bending process is controlled by special software that allows the operator to pre- high-strength,

select a geometry and to easily and quickly program bending parameters using a touch screen. A video screen at the control desk allows the entire bending process to be easily monitored at all times. This provides additional security for the operator through the complete bending process. An integrated printer allows the printing of all-important bending parameters at any time. The use of laser optical pyrometers, which scan a given section of the pipe during bending, registering continual, accurate temperature measurement of the heat zone, ensures precise optimal bending temperatures. AWS Schäfer Technologie GmbH – Germany Fax : +49 2739 8700 310 Email : info@aws-schaefer.de Website : www.aws-schaefer.de Automatic bundling lines with high productivity Cartacci Srl, Italy, the supplier of complete cold drawing and straightening machine lines, has produced two new automatic bundling and finishing lines for tubes. One of the two new automatic bundling lines was designed for tubes with diameter of 125mm for a customer in Germany, and the other for tubes with diameter of 272mm for a Russian customer located in Voljskiy. Cartacci offers equipment that provides high productivity through reduced operator intervention and an entirely computer- based working system. The new bundling lines were designed to have reduced maintenance costs, and were customised to the specific requirements of each manufacturer. Cartacci Srl – Italy Fax : +39 035 290514  Induction bending involves heating the pipe by a medium frequency inductor

 AWS Schäfer’s SRMBI can accurately bend even the heaviest of pipes

Email : info@cartacci.com Website : www.cartacci.com

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M ay 2009

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