US 12,421,811 B2
Insulated drilling systems and associated methods
Tony Pink, Houston, TX (US); Andrei Muradov, Houston, TX (US); Russell Gilleylen, Spring, TX (US); and Nooreldin Moussa, Spring, TX (US)
Assigned to National Oilwell Varco, L.P., Houston, TX (US)
Filed by National Oilwell Varco, L.P., Houston, TX (US)
Filed on Jan. 18, 2024, as Appl. No. 18/416,671.
Claims priority of provisional application 63/439,758, filed on Jan. 18, 2023.
Prior Publication US 2024/0240530 A1, Jul. 18, 2024
Int. Cl. E21B 17/10 (2006.01); E21B 36/00 (2006.01)
CPC E21B 17/1078 (2013.01) [E21B 36/003 (2013.01)] 37 Claims
OG exemplary drawing
 
1. An insulated drill pipe joint for a drill string of a well system, the insulated drill pipe joint comprising:
an outer sub comprising an inner surface defining a central passage extending between a first end of the outer sub and a longitudinally opposed second end of the outer sub, wherein the outer sub comprises a first connector located at the first end and a second connector located at the second end;
an inner mandrel slidably received in the central passage of the outer sub and defining a central passage extending between a first end of the inner mandrel and a longitudinally opposed second end of the inner mandrel, wherein both the first end and the second end of the inner mandrel are both radially and longitudinally spaced from the inner surface of the outer sub, and wherein an annular insulation compartment is formed that at least partially surrounds the inner mandrel and which is sealed from the central passage of the inner mandrel; and
an insulation medium located in the insulation compartment and has a greater thermal resistance than the outer sub.