Electric resistance welding

About: Electric resistance welding is a research topic. Over the lifetime, 16761 publications have been published within this topic receiving 154851 citations.

Process for the production of a composite metal part and products thus obtained

Abstract: The present invention relates to the production of metal parts whose core and surface must have different characteristics. Its subject comprises firstly a process for the production of a composite metal part by coating or hard-surfacing a metal core of low-alloy structural steel with a harder metal layer composed of a high-speed chromium-tungsten or chromium-molybdenum steel or a high-speed steel containing chromium associated at the same time with a plurality of elements such as tungsten, molybdenum, vanadium, and cobalt, this process being at the same time characterized in that this high-speed steel has a hardness higher than 57 Rockwell C, in that the low-alloy steel which constitutes the metal core is selected to be compatible with the said high-speed steel, in that the said high-speed steel is applied exclusively in the form of a prealloyed powder, and in that the coating or hard-surfacing of the core with this powder is effected with the aid of one of the welding processes of the follow-group: welding by means of a transferred or semi-transferred arc plasma torch, or welding by means of a laser torch, the operation of coating or hard-surfacing by welding being followed by heat treatment. Another subject of the invention comprises the products obtained by the abovedescribed process. It is particularly applicable to the production of rolls for cold rolling mills, rolling or forming rollers, shear blades, wear plates, and armor plates.

Welding electrode stickout monitoring and control

Abstract: Stickout of a welding electrode wire from a welding torch is determined during welding, and based upon a welding parameter, such as welding current Different relationships are used for the determination depending upon whether the welding wire is in a short-circuit condition or an arc condition The stickout may be converted to a standardized unit of measure to make it readily understandable to an operator The stickout may be logged and associated with other parameters and information, such as workpiece, operator, welding system, date and time The stickout may be used as the basis for an alarm or a disabling operation Moreover, the stickout may be provided on a readout for the operator It may also be used as a basis for controlling a wire feeding apparatus that retracts the welding wire to a desired stickout following a weld

Apparatus for vacuum welding of plastics envelopes

Abstract: The specification discloses vacuum packaging apparatus including welding bars, and clamping bars for holding the edges of the packaging envelope before, during, and after the welding operation Preferably the clamping bars may have grooves therein to facilitate escape of air from within the envelope during the evacuation phase A jet of air is blown across the welded edge to cool the weld and facilitate separation of the welded edges from the welding bars

Reducing bubbles in friction lap welded joint of magnesium alloy and polyamide

Abstract: The direct joining between AZ31B Mg alloy and MC Nylon 6 using friction lap welding (FLW) was performed over a wide range of welding parameters to clarify the effect of welding parameters on bubble formation for the purpose of obtaining high strength hybrid joints without bubbles. The volume of bubbles in the FLW joints was influenced by the amount of gases generated due to the pyrolysis of Nylon 6 and the amount of gases squeezed out of the joints during welding. An appropriate increase in welding speed, tool rotation rate and plunge depth can reduce the volume of bubbles. Strong FLW joint with area fraction of bubbles <8% was obtained after welding process optimisation.