During the recent years the drilling industry has undergone considerable changes .The outdated system of drilling has been replaced with modern machinery and technology which is called Mechanical Drilling Technology.
The Mechanical Drilling Technology which  is  being used for the drilling of Tunnels, Oil and Gas wells, Dams and other  major civil projects have contributed positively in the quality of work, safety factor, speed and durability and strength  of the projects.

Komeyl Kashan Chemical co. with its expertise and products which bear high international standard has been present in this field to assist this industry by producing and supplying sophisticated products ever since this new technology was adopted .Our drilling chemicals are very popular and command a high demand in this industry. We are the leading producers of these products in Iran. Internationally our products compete with other international well-known brands.
In the chapter we would like to introduce our Drilling chemicals used in the drilling of tunnels.  For chemicals used in the oil, gas and petrochemicals fields please refer to our following chapters.
During the last decade in view of the expanding urban population and traffic problems, construction of underground tunnels for public transportation (subways) has gained considerable importance. Various methods have been in operation for the construction of such tunnels. With the advent of new technology old system of drilling have been replaced first by semi mechanical method and then by fully mechanical drilling technology using TBM or Tunnel Boring Machines.
Under the old system many problems and risks existed, problems associated  with controlling the excavation of mud and the pressure of the earth, protecting the tunnel from collapsing, the nuisance arising due to flow of underground sewage and underground water into the tunnel, and above all, protecting the safety of the individuals working underground. These difficulties gave way to the adoption of the modern methods and technology for the construction of such sites under versatile geophysical conditions and thereby help make the tunnels deeper and lengthier.