Abstract: To resolve the puzzle of collapse and buried comes forth owing to scouring the wall of hole in construction of drillng long hole for sucking and exhaling mash gas. Adopt the technic of foam increasing pressure to solve the problem by advancing the pressure of foam current. The application of technic of foam increasing pressure in construction of drillng long hole for sucking and exhaling mash gas is feasible and economical.

Key words: foam drilling, increasing pressure equipment, mash gas, hole of sucking and exhaling