Dual-layer pipe wall composite-type gas pipeline and leakage monitoring method

Abstract

The invention relates to a dual-layer pipe wall composite-type gas pipeline and a leakage monitoring method for the pipeline, in order to mainly solve the problems that the gas pipeline operation safety in the high-hazard region is insufficient and the leakage point is difficult to confirm. The dual-layer pipe wall composite-type gas pipeline is characterized in that a clearance cavity is arranged between an inner pipe and an outer pipe; nitrogen displacement is carried out in the clearance cavity; the top of the outer wall of the outer pipe is provided with a plurality of vertical branch pipes communicated with the clearance cavity; the top ends of the vertical branch pipes are provided with concrete plates for sealing; the side wall of the outer pipe is communicated with a branch pipe which is bent downward; the tail end of the branch pipe is provided with a pressure blasting plate; the bottom surfaces of the concrete plates are provided with combustible gas probes which extend into the vertical branch pipes and are respectively connected to a combustible gas alarm and an industrial control computer in a remote monitoring room through a simulation signal wire and an RS485 data bus cable; and the industrial contro computer is used for calculating the position of pipeline leakage. The method can be used for determining the leakage point safely and rapidly.

Description

technical field [0001] The invention relates to the improvement of the structure of the urban gas buried pipeline, in particular to a double-wall composite gas pipeline, and also provides a leakage detection method when the pipeline is used to transport the urban gas, which belongs to the pipeline technology field. Background technique [0002] Urban gas pipelines are mostly buried underground in high-risk areas such as densely populated and trafficked areas. Since the pipelines are eroded by soil solution for a long time and there are many users of urban gas pipelines, it is impossible to add cathodic protection, and the walls of the pipelines will gradually become thinner and perforated. , causing gas leakage. Most of the current urban gas supply pipelines have a pressure range of 0.2-0.4MPa, which belong to medium-pressure pipelines. Most of the pipeline leakage is underground corrosion and perforation leakage. Due to the complexity of the surrounding environmental fact...

AI Technical Summary

Problems solved by technology

[0002] Urban gas pipelines are mostly buried underground in high-risk areas such as densely populated and trafficked areas. Since the pipelines are eroded by soil solution for a long time and there are many users of urban gas pipelines, it is impossible to add cathodic protection, and the walls of the pipelines will gradually become thinner and perforated. , causing a gas leak

Most of the current urban gas supply pipelines have a pressure range of 0.2-0.4MPa, which belong to medium-pressure pipelines. Most of the pipeline leakage is underground corrosion and perforation leakage. Due to the complexity of the surrounding environmental factors, the leaked gas often has a serious phenomenon of cross-gas, which accumulates in the nearby cable trenches and optical cable sleeves, or spreads to the surrounding rain drainage, sewage, horse gourd and other appendages, and the diffusion range is large. , it is found that there is hysteresis, and the leak point is difficult to identify

At the same time, due to many uncontrollable factors such as the start of surface transportation vehicles, artificial smoking, and ignition of electrical facilities, fires and explosions are prone to occur after gas leakage, causing heavy casualties, economic losses, and social impacts.

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