6498 results about "Arc welding" patented technology

The invention belongs to the welding industry, and particularly relates to an anti-sulfur well mouth valve body welding repair method, and in particular to a welding repair method of 4130 medium-carbon alloy steel in an anti-sulfur valve body with the hardness being 197 HBW -237 HBW. The anti-sulfur well mouth valve body welding repair method is characterized by comprising the following steps that a product to be repaired is cleaned to determine a damage position; a pit badly eroded needs to be polished; a workpiece is totally preheated to 130 DEG C before welding; filling of the pit is firstly achieved by adopting the argon tungsten-arc welding; then, the machined surface is subject to repair welding; the local or total heat treatment insulation is performed for 3 hours at 640 DEG C; in the welding repair method, preheating is performed to reach 130 DEG C before welding; the local or total heat treatment insulation is performed for 3 hours at 640 DEG C after welding; and the Ar+CO2 mixed gas arc welding is adopted in the method, and the method greatly increases the product utilization rate and improves the comprehensive efficiency.

A power source for an electric arc welding process, wherein the power source comprises an input stage having an AC input and a first DC output signal; a second stage in the form of an unregulated DC to DC converter having an input connected to the first DC output signal and an output in the form of a second DC output signal electrically isolated from the first DC output signal and with a magnitude of a given ratio to the first DC output signal; and, a third stage to convert the second DC output signal to a welding output for the welding process.

A short circuit arc welding system is disposed. The control scheme uses a current command signal to drive the output current. The command signal is comprised of a long-term current command that sets the long-term current command level and a real-time or short-by-short current command. Arc voltage feedback is used to determine if the desired arc length is present and to adjust the long-term command. The short-by-short current command is derived from real-time arc current feedback and is used to control the burn-off rate by an instantaneous, or short-by-short, adjustment of the current command. A function of the time derivative of arc power, less the time derivative of arc current, is used to detect, in real time, when the short is about to clear. A stop algorithm is employed that monitors the arc on a short-by-short basis. When the process is ending a very low current level is provided to avoid forming a ball. However, if a short is created, (indicated by a drop in arc voltage) after the low current level, a burst of energy is provided to clear of burn off the short. After the short is cleared, very low current is again provided to avoid forming a large ball. This is repeated until the wire stops and the process ends.