Butt welding

About: Butt welding is a research topic. Over the lifetime, 7153 publications have been published within this topic receiving 44467 citations.

Weld zone image processing method, welding management system, feedback system for welding machine, and butt line detection system

Abstract: PROBLEM TO BE SOLVED: To provide a measurement method and an inspection method for reducing the cost and improving the operation to enhance the reliability of a welded product when steel plates are butt-welded by laser beams. SOLUTION: In a lap weld zone of thin steel plates to be welded, two-dimensional coordinates of the weld line and parts in a vicinity of the weld line and information on brightness of each pixel are totaled by using an image sensor, weld defects and deviation between the butt line and the weld line are immediately detected, the welding condition of a welding machine is optimized on the real time basis, and the optimized condition is immediately fed back to the welding machine. The efficiency of the entire welding system is enhanced thereby, and the welding quality is uniformized to positively prevent weld defects. COPYRIGHT: (C)2005,JPO&NCIPI

Method and apparatus for welding current regulation for a resistance welding machine

Abstract: A method and arrangement are described for regulating the welding operation in a resistance welding machine by sensing the welding current and controlling the welding time. A first integrator (20) determines the desired total energy to be supplied to a welding spot from a desired welding current preset by means of a function generator (18) and a preset welding time. An integrating device (25) connected to the welding-current sensor (14) determines the actual energy supplied. A comparator (24) compares the desired total energy with the actual energy in order to switch off the welding current by means of a start/stop module (30) in the event of equality between desired value and actual value. In this manner, fluctuations in the supply voltage are compensated by lengthening or shortening the time during which energy is supplied to the welding spot in order to ensure the quality of the welding from one welding spot to another.

Friction stir welding of magnesium alloy ZM21

Abstract: Friction stir butt welding of Mg-Zn-Mn alloy ZM21 hot rolled plates (in three thicknesses — 5 mm, 10 mm and 25 mm) was investigated. Defect-free, full-penetration welds were produced after careful process parameter optimization. Microstructural studies, hardness tests, tensile tests, and bend tests were carried out. Welds produced in 5 mm thick (5-mm-welds) and 10 mm thick plates (10-mm-welds) showed relatively finer grains in the weld nugget and in the heat-affected zone compared to the welds produced in 25 mm thick plates (25-mm-welds). When compared to the base material, 25-mm-welds showed coarser grains both in the weld nugget and in the heat-affected zone. No significant hardness differences were observed between the welds and the base material. Tensile tests on 5-mm and 10-mm-welds yielded a joint efficiency of more than 75%. Bend performance of the welds was found to be satisfactory, falling only slightly behind the base material. Overall, the results show that friction stir welding can be successfully utilized for joining magnesium alloy ZM21 in various thicknesses.

Benchmark Investigation of Welding-Induced Buckling and Its Critical Condition During Thin Plate Butt Welding

Abstract: Welding-induced buckling is a special type of welding distortion occurring during thin plate butt welding and was investigated using both experimental and computational approaches for this benchmark investigation. In addition, the characteristic parameter and its magnitude for the occurrence of welding-induced buckling were also presented. Fundamental theories of the inherent deformation, finite strains, and eigenvalues of the structure stiffness matrix were considered to investigate welding-induced buckling. A series of experiments on thin plate butt welding with different heat inputs were conducted, and buckling behavior was observed from the deformed shape and the distribution of out-of-plane welding distortion. Transient nonlinear thermal elastic–plastic finite element (TEP FE) and elastic finite element (FE) analyses were conducted to predict welding-induced buckling, and the results were in good agreement with the measurement data. Criteria for the occurrence of welding-induced buckling were proposed and discussed. Inherent deformation was considered as a characteristic parameter of buckling behavior during welding, and its critical magnitude was calculated using a loading incremental method and eigenvalue analysis with good agreement.

Butt welding method for clad tubes

Abstract: PURPOSE:To obviate tempering treatment after welding when the clad tubes whose outer layers and inner layers are formed of carbon steel or low alloy steel and stainless steel or high alloy steel, respectively are subjected to butt welding at a setting field. CONSTITUTION:Before butt welding at the laying field, cladding by welding is performed on at least the end faces of the outer layers 1 to form cladding parts 3 by using a stainless steel or high alloy steel electrode and tempering treatment is carried out on base metal outer layer parts which are heat-affected and hardened by welding. At the setting field, the cladding parts 3 of the stainless steel or the high alloy steel are abutted on each other to perform welding.