METHOD FOR SECONDARY OPENING OF PRODUCTIVE BED Russian patent published in 2000 - IPC

FIELD: oil and gas production industry. SUBSTANCE: method can be used in performing perforation operations in wells which opened productive beds due to drilling. According to method, perforation passages in walls of well are made by drilling with using drilling bit. After each penetration of drilling bit over length of its rod, drilling bit is automatically lengthened by another rod which is automatically delivered from holder to drilling bit feed mechanism. After perforation passage reaches its design depth, drilling bit feed mechanism is disconnected from sectional rod of drilling bit and is brought to initial position. After that, drilling bit is turned by its mechanism through preset angle by rotation of mechanism and drilling bit is brought to another holder for receiving another drilling bit. Then, by performing similar procedure, other passages are drilled up. By continuing aforesaid operations, created is system of perforation passages in one plane in rod of bed. Application of aforesaid method allows for drilling perforation passages in rock of bed to maximal depth of penetration of fouling fluids. EFFECT: higher efficiency. 9 dwg