City gas pipeline should be set the place of pneumatic valve

a, the starting point of the gas delivery tube.
2, reserve standing import and export.
3, compression machine import and export of the chamber.
4, across the railway, both sides of the main rivers.
5, the starting point of medium voltage branch pipe. The end of the
6, intermediate pressure main.
7, voltage regulator of the outdoor inlet pipe, but as the starting point of the city from the medium voltage branch pipe pneumatic valve spacing is less than m is not set.