Inventor
CARLSON DOUGLAS W
US10 patents
⚠️ This page may combine multiple inventors who share the name “CARLSON DOUGLAS W”. Patents are grouped by organization below to help distinguish them — per-person disambiguation is on the roadmap.
HYDRIL CO
9 patentsUS5430087AJul 4, 1995
Carbon black pair with different particle size and improved rubber stock
HYDRIL CO91 citations94
US5294253AMar 15, 1994
Carbon black system and improved rubber stock
HYDRIL CO52 citations94
US5713581AFeb 3, 1998
Fibrous seal for blowout preventer
HYDRIL CO44 citations91
US5542454AAug 6, 1996
Free flow low energy pipe protector
HYDRIL CO29 citations91
US5465759ANov 14, 1995
Variable diameter pipe protector
HYDRIL CO38 citations91
US5100950AMar 31, 1992
Rubber and fluorocarbon micropowder composition
HYDRIL CO18 citations81
US5339864AAug 23, 1994
Safety sub for retaining drilling fluids
HYDRIL CO11 citations73
US5364064ANov 15, 1994
Safety sub with asymmetrical wall elastomeric closure for retaining drilling fluids
HYDRIL CO7 citations72
US5180137AJan 19, 1993
Ram type blowout preventer having improved ram front packings
HYDRIL CO11 citations72