（1）Friction welding drill pipeIt is believed that when overhauling the electric pump in the ground well, if the electric pump is brought out from the well casing, if the wellhead is not sealed properly, some wastes will be artificially thrown into the well, which will block the normal upwelling of the water intake section at the bottom of the well and cause the water output of the electric pump to decrease when lifting water.

（2) After the sand gushing phenomenon occurs in the ground well, if the sand gushing leakage point cannot be blocked in time, part of the sediment in the formation will be transferred to the pipeline by the electric pump, and part will settle to the bottom of the well. With a large amount of sediment entering the well, the filter pipe part of the well pipe will be backfilled with sediment, causing the water in the water intake section to not surge normally, so the water output of the electric pump will decrease when lifting water.

（3) Part of the filter pipe of geothermal well casing is made of filter by wire winding method. When the well is idle and does not carry water, the wire winding on the filter reacts with some minerals in the water to calcify, and calcification will block the waterway, causing the water outside the formation of the water intake section to not flow into the well, and the water output decreases when the electric pump pumps carry water.

geothermal well

（4）Friction welding drill pipeIt is considered that if the designed height of the wellhead is lower than the ground level, there will be a large amount of water around the wellhead.(or when it rains), the accumulated water will flow into the well. When the accumulated water flows into the well, some light waste garbage or soil on the ground will also be brought into the well. As the accumulated water flows into the well, the waste and soil will settle into the bottom water filtration pipe section. After a long time, the waste and soil will block the filter of the water filtration pipe, so that the water in the water intake section cannot rush up to the position where the electric pump normally, the phenomenon of water extraction decreased.

（5) In case of abnormal phenomena such as sand gushing and water output reduction in the ground well, the ground well shall be properly inspected and overhauled in time. The failure of geothermal well will not only affect the production, but also block the water pipeline and burn the electric pump frequently. In serious cases, cavities will be formed between strata. For example, the collapse of cavities close to shallow strata will cause foundation settlement, and the settlement of foundation will cause the buildings around the well to tilt. Therefore, the serious consequences of failure to repair the geothermal well are immeasurable.

（6）Friction welding drill pipeThe essential instrument and equipment for the water well maintenance project is the underground TV. The underground TV detection work is also the step of the water well maintenance project. The underground TV can clearly display all the conditions in the well on the ground display. The cause and degree of the failure of the water well will be collected by the underground TV in real time, according to the collected images in the well.