1. Introduction of horizontal directional drilling The horizontal directional drilling is without excavation surface conditions, laying a variety of underground utilities (Трубы, Кабели, Др.) of a kind of construction machinery, it is widely used in water supply, Электричество, электросвязь, газ, газ, oil and other pipeline construction, подходит для песка, Глины, pebbles and other DeKuang, most of the hard rock …