Improving the quality of production of power tranformer tank using six sigma approach in tank fabrication

The transformer is an essential part of the reliability of the electric power system. The failure of the transformer causes the loss of the electrical network system. There is a poor quality of the transformer tank, namely the emergence of rust so that which can cause tank leakage. Problems that often occur must be analyzed more deeply. Researchers use the Six Sigma approach, a systematic improvement method to parse issues and solve them according to a priority scale. Sigma Tank Fabrication (TF) level is 2.76. The most dominant problem comes from the welding and painting process, namely 77.1%, where painting thickness defects are the most dominant under specification, followed by welding defects in the form of incomplete fusion, porosity, and spatter. Potential problems that arise are analyzed using the FMEA method to determine the priority of problem-solving. Delivery targets, welding parameters, checking procedures, working methods, unsuitable materials, conformity standards, work machines, inadequate human resources, and working environment are priorities for potential problems that must be solved. Propose improvements to procedures, standards of conformity, and consistency to reduce production defects complained of by customers.