Method of excavation of oil and gas-producting wells

Abstract

A method of opening oil- and gas productive layers has the steps of cutting of two slots in one plane so as to form a partition of rock between them and so that stresses from surfaces of slots are redistributed onto the partition and create in it additional pressure, and selecting widths of the slots and the partition such that the partition becomes so stressed that it self-destructs, and as a result a single slot is formed with a length which is equal to lengths of both initial slots and the partition.

1 . A method of opening oil-and gas productive layers, comprising the steps of cutting of two slots in one plane so as to form a partition of rock between them and so that stresses from surfaces of slots are redistributed onto the partition and create in it additional pressure; and selecting widths of the slots and the partition such that the partition becomes so stressed that it self-destructs, and as a result a single slot is formed with a length which is equal to lengths of both initial slots and the partition. 
     
     
         2 . A method as defined in  claim 1 , wherein the slot is cut over a height 1 not less than a diameter of a well, a cutting device is moved along the well over a distance determined as follows:
     H >(σ· d )/2/β 3 {1+|1+4(σ 3 /σ| 1/2 }   
       Where d is a diameter of the well, in m,
 σ—is a horizontal stress at a depth of the layer, Mpa, 
 σ 3 —is a cubic strength of rocks of productive layer, Mpa, 
 h—is a distance, m; 
 
       then cutting a next slot over the same height; destroying the formed partition; and repeating the steps of cutting and destroying over a whole thickness of an interval of work.