Choke and Kill (C&K) Lines : External conduits arranged parallel to the riser pipe used for circulation of fluids into and out of the formation to control well pressure. (RP 2%)
The Mudblogger (Oilfield, Energy and Related Photographs), Oil Field Glossary, TX, USA 2014. http://mudblogger.com/oilfield-glossary/, (Oil - Amer) {777}