A pneumatic drilling chip removal system for removing drilling chips from a well bore, comprising sub-surface drilling equipment having a plurality of components and a drilling bit, a central passageway extending through the components and to the air jets in the drilling bit, wherein at least one component...http://www.google.com.au/patents/US5584352?utm_source=gb-gplus-sharePatent US5584352 - Pneumatic drilling chip removal system and method
