Changes can occur in the metallurgical structure of the base Cardboard Packaging Machine to the weld (heat affected zone or HAZ). The changes can cause embrittlement or degrade the material properties. In addition, upon cooling, the weld metal shrinks to a greater extent that the base metal in contact with the weld (HAZ) exerts a drawing action. Therefore, post weld heat treatment (PWHT) is necessary to restore the ductility of the material and thus prevent stresses, shrinkage, and cracking. Finally, because welding usually affects the pressure-retaining parts of the boiler, the boiler shall be subjected to a hydrostatic test of 1陆 times the MAWP for at least 15 minutes.

You may not be aware of the fact that a welder is actually a very highly trained professional. They can also have a formal education through a vocational training school. Here are some of the on the job activities and special requirements you can expect to find when you get into the field looking for welding jobs.

It sounds simple to say that a welder melds metals together for the purpose of construction, but there is much more to the job than that. A welder can be found in factories, or manufacturing plants, and is also needed where there are production lines such as automobile plants or in the steel working industry.

There is quite often a need for welders who will be working outdoors in all kinds of weather, on different types of Clamshell Packaging Machine or even oil rigs. There are welders needed for oil pipe line construction and repairs, such as the Alaskan Pipeline project. Government projects for bridges and office buildings need welders who know what they are doing to finish these projects on time and within budget.