STRESS RELAXING METHOD

• Main Authors: KUBO MASAO, MATSUMOTO KOICHI, OKADA KENJI, TERADO SHOKI
• Format: Patent
• Language: English
• Published: 22.06.1993
• Subjects: CLADDING OR PLATING BY SOLDERING OR WELDING; CUTTING BY APPLYING HEAT LOCALLY, e.g. FLAME CUTTING; MACHINE TOOLS; METAL-WORKING NOT OTHERWISE PROVIDED FOR; PERFORMING OPERATIONS; SOLDERING OR UNSOLDERING; TRANSPORTING; WELDING; WORKING BY LASER BEAM

PURPOSE:To relax tensile stress inside members, to accurately presume and grasp the quantity of relaxation and to improve stress corrosion cracking resistance by arranging a pressurizing member at the position separated from a weld zone of the members. CONSTITUTION:A clamping ring 7 is arranged at the position separated by an area F in the axial direction of pipings 1 from the center of the weld zone 2. The pipings 1 in a state being used at the high temperature are clamped uniformly on the circumference from the outside in the radial direction by the clamping ring 7. Material having a thermal expansion coefficient smaller than that of material of the pipings 1 is used as material of the clamping ring 7, by which the great clamping force can be obtained. The compressive stress is given not only to the circumferential direction stress but also to the axial direction stress by this clamping force and the tensile stress during operation is reduced.