PSI - Issue 27

Eko Surojo et al. / Procedia Structural Integrity 27 (2020) 14–21 Surojo et al. / Structural Integrity Procedia 00 (2019) 000 – 000

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simple because it does not require a lot of special preparation and unlimited space for the welding operator. Therefore, the cost required is relatively cheaper than dry welding (Orr, 2006). However, direct contact of wet welding with water can cause some negative impacts such as the arc flame being unstable, decreasing the mechanical properties of the material, and can increase the cooling rate of the welding material (Swierczynska et al., 2017). a. b.

Fig. 1. The condition of underwater welding: (a) dry welding (Majumdar, 2006), and (b) wet welding (Nixon, 2000).

Underwater welding technique is an appropriate technique for emergency repairs in the event of structural damage in the middle of the sea that does not allow dismantling to be carried inland. So that welding is considered to save time, energy from workers, and costs (Orr, 2006). Wang et al. (2017) argue that underwater welding can serve to repair and maintain underwater structures that are generally used in ship construction, oil, and gas piping offshore and nuclear power plants. However, underwater welding can have a negative impact in the form of defects in welding material. It caused by trapped hydrogen gas in the weld metal, which can have a detrimental effect in the form of cracks, which can reduce the reliability of welding structures and cause steel to become brittle and broken (Chen et al., 2020). Chen et al. (2018) argue that the effect of water depth on arc behavior, air bubble characteristics, and welding performance on the UWW FCAW process. The results show that the depth of the water decreases the size of the droplet, stability of arc weld, and produces a lot of pores on the weld metal. So, it is necessary to consider in the selection of appropriate techniques for repairing underwater structures.

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Fig. 2. Underwater welding research.

Fig. 2 shows many articles about underwater welding from 2001 to 2020 that experienced fluctuations. The topic of discussion of underwater welding in this period was very diverse, including the development of welding technology, weld metal microstructure, mechanical properties, any elseSo that the focus of the discussion is comprehensive, the