Onsite Technical and Economic Performance Evaluation of PWT (Pipeline Welding Technology): A Comparative Analysis with CRC-Evans Welding Technology

Abstract

During cross-country underground pipeline construction welding is one of the major construction activity. At various parts of the world, many pipeline welding machines are in use to produce defect-free economic pipeline joints. Every weld machine manufacturer claims its own advantages and other’s drawbacks. Two famous welding machine manufacturing companies for pipelines are PWT (Italy) and CRC-Evans (USA). Thus, the current work at the cross-country gas pipeline construction site from Vijaypur (MP, India) to Dadri (UP, India) (VDPL) is taken up to determine which of the above two mentioned machines are technically better and relatively cheaper while determining weld joint cost and overall pipeline construction cost. Data of two construction sites of VDPL namely Guna and Mathura are collected for weld joint construction and repair. The sites were constructed by ESSAR and EIL for GAIL. The carbon steel pipeline being laid was of 48” nominal size. A detailed cost analysis of the machines is estimated by considering all the related man, machine and material cost, both for mainline weld and weld joint repair. Technical performance of the weld machines is evaluated by comparing various weld parameters for pipeline weld joints. Performance of both of the machines is found to be comparable and almost equal in terms of total cost involved but the repair cost of PWT is less than CRC. Both PWT and CRC are found to produce weld defects with defect of incomplete fusion (IF) more frequently. Suitable remedies are suggested for improvement.