Field implementation and technical evaluation of hot tapping on active gas pipelines

Hot tapping has become an essential technique for pipeline modification in situations where shutdown is impractical or economically undesirable. This study presents a comprehensive field evaluation of a hot tapping operation performed on an active API 5L Grade B natural gas pipeline within a regional distribution network. The objective was to document the technical execution, assess weld quality through non-destructive testing (NDT), evaluate pneumatic leak testing, and analyze the performance of the drilling process, including coupon retrieval. A split tee and trunnion-mounted ball valve assembly were installed following controlled welding procedures, and weld integrity was verified using PT, MPI, and UT examinations, all of which indicated defect-free joints. Pneumatic testing using staged nitrogen pressurization confirmed full sealing performance without pressure loss or leakage indications. The hot tapping machine operated smoothly, producing a cleanly cut coupon successfully retrieved by the safety wire. The operation also incorporated risk mitigation controls such as gas monitoring, tool verification, and procedural discipline, resulting in zero incidents. The findings align with established literature regarding the effectiveness and safety of modern hot tapping methods. Overall, this case study provides practical insights into field implementation, supporting the broader adoption of hot tapping for maintaining service continuity in active gas pipeline networks.