Economic Model for Welding Natural Gas Pipelines in Mountainous Areas

Welding of long-distance pipelines is a crucial step to ensure the safe operation of pipelines. In mountainous regions, the actual welding efficiency is often significantly lower than the theoretical efficiency, and the lack of standardized guidelines for on-site selection leads to a general preference for more mature semiautomatic welding combinations. This tendency hinders the broader adoption of automated welding technology for pipelines. To address this issue, we established cost functions for individual welds and total welding costs, clarifying the proportion of labor, equipment, and material costs in different welding methods. We developed a total welding cost function for various welding methods, forming an economic welding matrix to recommend welding techniques suitable for different terrains and construction segment lengths, providing a reference for selecting on-site welding methods. Additionally, an economic model for welding natural gas pipelines in mountainous areas was established from the perspective of engineering economics. This model not only considers the direct costs of the welding process but also reflects the impact of terrain and project scale on economic efficiency, offering guidance for selecting welding methods in complex environments. Finally, the accuracy of the economic model was validated using a specific construction segment.