Horizontal well workover technology present situation and development trend

In the downhole operation of horizontal Wells, the pipe string is subjected to the combined action of many kinds of loads. The pipe string may bend sinusoidal or spiral under the action of axial compressive stress, which will also increase the friction between the pipe string and the wellbore wall. Because of the existence of friction, to the milling, salvage, unstuck, sand and other construction to bring adverse effects. This paper describes the characteristics of horizontal well in fishing, sand washing, unlocking and casing milling. The paper introduces the development of horizontal well application, such as drilling technology matching for complex structure wells, high-level completion of lateral Wells, radial lateral wells in low permeability reservoirs and supporting technology for completion and production of horizontal wells.