Patent ID: 8499854

Claim:
A cool fluid circulation system (CFCS) for circulating cool drilling fluid across a rotating control device (RCD) and RCD insert operatively connected to a well head having a hot drilling fluid return outlet, the CFCS comprising: a body for operative connection between and for separating the RCD and the hot drilling fluid return outlet at the well head, the body including a CFCS inlet for injecting cool drilling fluid adjacent the RCD insert and a CFCS outlet for removing partially warmed drilling fluid; a void space within the body adjacent the CFCS inlet and CFCS outlet for containing and circulating a volume of cool drilling fluid adjacent the RCD insert, and creating a buffer zone between the hot drilling fluid return outlet and the RCD insert, wherein the cool drilling fluid is in direct contact with the RCD insert; and wherein during cool drilling fluid circulation, the cool drilling fluid is in direct contact with the hot drilling fluid between the buffer zone and the hot drilling fluid return outlet, preventing the hot drilling fluid from directly contacting the RCD insert.