Stud welding stud welder just experienced the emergence and development process for decades, with full cross-section welded stud welding, standardized operation, high efficiency and quality and reliable. With the constant development of the technology industry has been widely used [3] [4].
According to the different stud welding works, generally divided into the energy storage stud welder pull-arc stud Welding Electrode and stud welding two categories.
[Edit this section] energy storage stud welder
Energy storage stud welder is welding power supply, rectifier, storage capacitor, controller, gun, to pliers, welding cables and other components. Obtained by controlling the capacitor charging welding voltage, welding discharge thyristor discharge completion time 1-3 ms [1] [2]. It features a short time, thermal deformation is small, it is suitable for sheet metal stud welding in shipbuilding, automotive, cabinet, cabinets and other industrial applications is very broad.
Energy storage stud welder has experienced three stages:
1-loop control: the welding operation is fully analog controls, voltage regulators for the knob stepless adjustment, no digital display menus and working voltage. Currently most of the stud welder has made use of such control devices. The advantage for the product cost and low technology content, products are easily imitated, the disadvantage is due to the use of knob stepless voltage regulation, when the ambient temperature or temperature changes, voltage change, consistency is not easy to control the welding effect.
2-loop control with voltage detection: the stud welder in the first stage, based on the charging section to be included in the charging voltage detection module. Voltage regulator for the stepless adjustment knob, LED displays the current charge voltage, non-working menu. Part of the use of such imported stud welding control. The advantage is you can visually understand the current voltage value, production costs and relatively low-tech, the drawback is also at ambient temperatures or temperature changes, the charging voltage change, to be adjust to meet the requirements through the knob to adjust the voltage.
3 MCU intelligent control: such control with the first two stages are quite different from the digital circuit control capacitor charging and discharging, power-down features such as automatic compensation, the use of touch-button, digital display working menu, and Rated charging current volume, some use of such imported stud welding control, some domestic manufacturers are also being developed. The cost of the stud welding stage and technical content are high, the advantage of man-machine communication interface is friendly, easy to operate, precise charge, when the power of natural wastage will be automatically compensated, independent of temperature.
Discharge stud welding without gas protection, the operation is relatively simple and very suitable for automated production line requirements, this technology has been widely used in automotive welding welding production line. Stud welding productivity depends on the capacitor charging speed, manual welding up to 8 / min, automatic welding of 60 / min.
Have improved energy storage stud welding and stud welding-type pressure-type stud welding two.
Enhance the style pull-arc stud welding is similar to short-cycle stud welding arc, it is suitable for aluminum and brass stud stud welding, the welding time of about 1 millisecond. Welding, screw gun to bring a first height (the height of lift can be different according to the diameter of the screw adjustable, adjust the accuracy of 0.2mm), then in the spring down under the pressure of instant impact, strong impact and the current through the weld nails head and make it melt, so that welding between the nail and the face is ionized by welding the gap between the nail and face the ionization arc, the result is the shortest period of time (about 1 ms) to stud flange immersion bath, the formation of the oxide film to complete the welding process.
Pressure stud welding of the welding time of about 3 ms for low-carbon steel for stainless steel studs and stud welding copper.
[Edit this section] pull-arc stud welding
Arc stud welding is a welding power supply, controller, gun, to pliers, welding cables and other components. However, most welding equipment welding power supply and controller into one, called the host.
And energy storage stud welder welding works differently, no pull-arc stud welder capacitor charging process, Copper Welding Electrode power through the discharge, the discharge thyristor control to complete the whole welding process, the discharge time of 5-500 ms .
More advanced control method is to use intelligent control chip for a more accurate and timely control of welding process, welding current, welding time and other parameters.
Welding power source is generally thyristor controlled rectifier or inverter-type arc welding. Pull inverter arc welding rectifiers, small size, light weight, good dynamic characteristics, is undoubtedly the first choice for welding, but limited by the high-power devices, the current capacity of the welder, or thyristor controlled rectifier for arc welding main. But no matter what the structure of welding power, its security requirements should be consistent with GB15579.1 requirements. For arc stud welding machine welding power source should have the upper load voltage 70-100V), high output voltage (≥ 44V), and renewed the forefront of welding current, low internal impedance and so on.
Arc stud welding is mainly used for cylinder head stud (no head) shaped nails nails and welding welding, welding diameter generally Φ8-25mm. Short cycle welding is mainly used in the automotive industry. Stud (stud) is generally used when welding or gas to protect the ceramic ring, you can not short cycle welding gas.