Looping is a pipeline section laid parallel to the main gas pipeline. It is connected to the linepipe constructively and technologically. It is tied-in for increasing flow efficiency of the linepipe or for reducing (decreasing) the pipeline pressure loss, as well as for spacing extension – the distance between the neighboring compressor stations and their reduction in number. The gas pipeline section with a looping has a lower flow rate of the product being conveyed via the main gas pipeline, which leads to the reduction of the total gas pressure loss for flow resistance overcoming. That is why, with original gas pressure remaining constant, an increase in the flow efficiency of a gas pipeline in general is directly related to the looping length. As a rule, the length of a looping being laid is a multiple of the pipeline valves spacing (distance): 25 to 30 kilometers. With the looping development, its length increases and finally equals the total length of the main pipeline, therefore becoming its second string.