Gas laser welding reduces vehicle manufacturing costs (helium, argon) - Helium shielding gas results in the smallest average vapor particle size. This shows that pure helium is the best choice for controlling particle size for CO2 or YAG laser welding. We must admit that helium does have a higher ionization rate and a lower plasma formation voltage than argon, but its molecular weight is smaller. Therefore, helium shielding gas requires a large flow rate to ensure that the metal vapor in the path of the laser beam is effectively expelled. Since the unit cost of helium is higher than argon, this increases the average cost per foot during the welding process.

In order to optimize the shielding gas to achieve the suppression of plasma, the expulsion of steam particles and the reduction of unit costs, we consider the use of up to 40-50% argon gas mixture. The higher the specific gravity, the smaller the flow rate required to expel the vapor particles from the gas mixture. The gas mixture also provides a longer inert atmosphere during the welding pool curing process, resulting in greater welding speeds. It also reduces the amount of trapped gas, which reduces the scrap rate due to porosity. Secondly, the reduction of curing rate promotes the growth of grain and the reduction of internal stress, which increases the fatigue strength. Weld cracks due to the higher aspect ratio (weld depth/width) and subsequent stress are almost eliminated because the addition of GMAW filler metal increases the width of the weld surface.

In the gas mixture, the appropriate addition of a small amount of carbon dioxide and/or oxygen, or as a secondary protective gas for the GMAW process, can further improve the performance of the bead. The helium-argon mixture is easy to produce higher arc voltage, and the resulting bead shape is wider and arc stability is higher.

Therefore, 3-10% carbon dioxide can be added to stabilize the transfer and shrink the arc. In some cases, 1-5% oxygen can be added to achieve excellent arc stability while achieving a better connection (wetting) at the welded edge. Compared with carbon dioxide gas mixture, oxygen is easy to provide a wide and shallow penetration distribution due to its lower ionization rate and higher thermal conductivity.

Once the gas mixture has been finalized to the required quality and productivity standards, it is also necessary to consider how to economically transport them to the site of use. Users can take advantage of a low-cost liquid argon supply by mixing these protective gases at the production site. Why not pay the price of premixed high-pressure helium tanks for argon, carbon dioxide or oxygen?

Argon can be transported economically in liquid argon tanks to meet monthly consumption of up to 35,000 cubic feet, which corresponds to a monthly gas mix of 87,500 cubic feet. Larger monthly consumption of Argon can be used to optimize the cost level using batch supply. The analysis also takes into account filling losses, monthly equipment costs, contractual constraints on bulk supply, and shipping costs.

Helium, on the other hand, is usually supplied through high-pressure TubeTrailer or cylinder sets. Mixing in the field requires a mixing system that is able to accurately regulate the tiny ingredients from 0-100%. The total mass system can be monitored by placing an analyzer at the outlet of the mixer, which will alert if the mixing ratio exceeds the error range. Software and alarm systems exist that can transmit this information to a desktop computer, or send it further afield by fax or email.

The reasonably designed hybrid laser gas transfer system enables users to achieve higher welding speed and correspondingly obtain higher productivity. Paying attention to the parameters of the protective gas, such as type, flow rate, and impact Angle, will improve the welding quality and reduce the beam absorption and scattering effect.

About Us

Founded in 2013, Zibo Dijia Special Gas Co., Ltd ,based on more than thirty years of research and production of hydrogen chloride gas, Dijia as the window to actively explore new markets and integration of special gas resources for domestic and foreign customers. Zibo Dijia has full range of gases, including Industrial gases,specialty gases,electronic gases, high purity gases, mixed gases, electric lighting gases, ultra-pure gases, laser gases, medical gases, calibration gases, a total of ten series of more than 100 varieties, with strong market competitiveness.