#Framebyframe software crackLarge flaws or high stresses can lead to crack growth and ultimately to unstable propagation and structural failure. Consequently, engineering design often requires evaluation of the maximum flaw size and operating stress level for safe operation. An engineering structures, especially aluminum structures of train vehicles, usually contain flaws or micro cracks. Predictive fracture mechanics within numerical codes has become a necessity for the virtual design of an automotive and train vehicles but at the same time it is still very difficult to achieve. There are several possibilities of reducing the heat input such as changing the welding method or automatization of used welding method to higher welding speed, adjusting the technological process, and reducing or completely cancelling welds in some FEM defined places 5. It also minimizes or eliminates the necessity of a subsequent straightening and heat treatment of the weldment. During welding, the heat input must be kept at a low range, to ensure less internal stress and deformation being created. In order to precisely and reliably predict the welding deformation during assembly process, all these factors must be taken into account in addition to the local shrinkage 4. Contributing factors to gap and misalignment are initial geometrical error, welding sequence, positioning, restraint and tack weld. The second is root gap and misalignment produced in the joint before or during welding. They are strongly influenced by heat input, shape of penetration, plate thickness and joint type. These three kinds of local deformations can be taken as inherent deformations 3. Basically, local shrinkage can be divided into three categories: longitudinal shrinkage, transverse shrinkage and angular distortion. The first is local shrinkage due to rapid heating and cooling in the weld zone. Generally, there are two major causes of geometrical error in the welded structure 2. Or for aluminum structures is possible change welding to brazing or bonding. Therefore, it is very important if it is possible reduce welding. Welding induced distortion not only degrades the performance but also increases the cost of a fabricated structure. Typically, these blocks are all-welded, thin-plate structures for example train door frame system. For instance, the assembly process in train building essentially involves the joining of large blocks. Welding technology is one of the main joining methods and widely used in industries to assemble various products such as ships, vehicles, trains. Rolling stock manufacturers, systems suppliers and train operators are facing the technical challenge to meet the continuously rising requirements for safety, passenger comfort and barrier-free use for persons with reduced mobility 1. Increasing passenger volumes and a progressing use of public transport require highly reliable entrance systems. The input materials include metallurgical intermediary products that must meet requirements of the design (strength, toughness), technology (formability, weld ability), as well as economy. Due to its excessive segmentation and specific customer needs, it is impossible or causing complex problems and increased costs to produce aluminium frame doors without welding. During manufacturing of door systems for trains or vehicles is suitable selecting proper and suitable primer construction.
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