Improved Babbitt Welding Techniques for Journal Bearing Repair in a Hydrogen Compressor

Abstract

This research introduces a practical step to successfully weld Babbitt using the soldering method. This step took the work from failure in rehabilitating the bond layer from repeated failure to success in welding journal bearing lined by Babbitt. By incorporating additional practical steps into the existing process, we have significantly enhanced the performance of essential equipment, particularly in the power former no.1 (High-octane gasoline production unit). In addition, this study set the temperature necessary for distributing the bonding layer to be 250°C and cleaning by wire brushing with diluted hydraulic acid HCl of 35% concentration to develop the bonding layer (a layer where the white metal penetrates the pores of the bearing metal due to the physical capillary property, a layer thickness ten mils as a maximum). It is the successful change in the previous usual work steps. It is considered a practical additional step that allows for a good combination of the base metal (metal-bearing) and the Babbitt sliding bearing. Furthermore, our research confirmed our previous study that the ratio (1:25) of ammonium chloride powder (NH₄Cl) has significantly improved the penetration of the base white metal through the base metal of the bearing and improved repair of the damaged surface of Babbitt. The procedures employed in this study are based on practical experiments and followed by visual inspection for the evaluation of the soundness of the welding line, turning the welded part to the required allowances, die penetrant nondestructive inspection, and evaluation of the mechanical performance after a period in the annual maintenance of the power former No. 1 unit. This has resulted in notable enhancements in the compressor’s strength, fatigue strength, toughness, and mechanical properties, embed ability, compatibility, conformability, corrosion resistance, and hardness, as evidenced by our comprehensive testing and analysis. Another significant achievement of this study is the ability to repair the Babbitt that was damaged by the sliding bearing during operation, eliminating the need for complete replacement. This not only saves valuable time and cost but also ensures the required quality, a testament to the efficiency and effectiveness of the new method.