It is about the ring screw thread smoke channel of the boiler shell type gas tube in the boiler field.
锅壳式烟管锅炉烟管内置水管的环形螺纹烟道，它涉及锅炉领域。
2
Clay content of gas reservoir is high, the clay takes on the scaly, silk-thread form, bridging the pore and clogging or plugging the pore structure and throat.