Vacuum Insulated Tubing

Thermal Production Pipe: Vacuum insulated tubing is composed of host string, thermocase, coupling, sealing ring and liner pipe. The insulated tubing adopts double-walled enclosed welded structure; the inner tube is treated with prestressingduring welding. There are multi-layer insulation structure in the annulus space and getter in the thermocase that can reduce heat transfer, energy loss by convection and radiation, and avert hydrogen explosion and radiation, and prolong the service life with special handicraft treatment.
The vacuum insulated tubing applies to such operating condition as the temperature of heat carrier is not over 350 ℃. The insulated tubing mainly applies to steam thermal recovery well with “huff and puff” and “steam drive” as well as heavy oil well with “integration of production and injection”. Using vacuum insulated tubing correctly can not only reduce the heat loss of steam injection and guarantee steam quality but also decrease casing deformation and protect cementing casing.
Vacuum Insulated TubingVacuum Insulated Tubing
The thread of vacuum insulated tubing is API buttress thread. With PTFE sealing ring in the coupling and insulated liner in the annulus space between inner and outer tube, they can not only assure positive confinement among pipe strings and connection reliable but also insure the laminar follow state of steam injection and reduce the resistance of steam transport and heat loss in the coupling.
Vacuum insulated tubing is manufactured in accordance with the standard of SY/T5314-94 Vacuum insulated tubing. Insulated tubing with different performance grades can meet the needs of thermal recovery for heavy oil, super heavy oil with different depth and horizontal well.
The vacuum insulated tubing with high performance, which the thermal conductivity is less than 0.015 W/m•℃ (equal to vacuum insulated tubing of grade D and E in SY/T5324-94), is the fourth generation vacuum insulated tubing for heavy oil thermal recovery leading in the domestic market.
Vacuum insulated tubing of grade D and E applies to the heavy oil well and super heavy oil well, and can improve the quality of injected steam and development effect after steaming; it also applies to production well with high water, and protects oil string, too. At the seam time, the insulated tubing can’t only save fuel and shorten steaming circle obviously but have distinguished economic and social benefit.
Supercritical insulation tubes (SIT) is a new product territory in which hasn’t been set foot in the world, and also the fifth generation product of vacuum insulated tubing in our company. The product can meet such well condition that temperature of steam injection is not more than 390℃; Injection pressure is not more than 36MPa. It can meet the requirements of the steamed thermal recovery for both heavy oil well and super heavy oil well.
Specification of Sub-critical Vacuum insulated tubing

  OD × ID OD: Outer diameter ID: Inner diameter Basic Parameters Tensile strength Collapse Resistance Cementing Casing
OD × wall Thickness ID × wall Thickness OD of coupling Connecting thread   Normal temperature Steam injection  
  mm in mm mm mm kN MPa MPa in
1 73×40 2-7/8×1.61 73.02×5.51 48.26×3.6 88.9 2-7/8USS 385 30 28 4-1/2
2 88×40 3-1/2×1.61 88.9×6.45 48.26×3.68 108 3-1/2USS 402 30 28 5
3 88×40 3-1/2×1.995 88.9×6.45 60.32×4.83 108 CYG25.4 432 30 28 5
4 114×62 4-1/2×2.441 114.3×6.88 73.02×5.51 132 117 506 26 24 7
5 114×76 4-1/2×2.992 114.3×6.88 88.9×6.45 132 10.361 537 26 24 7
6 127×76 5×2.992 127.0×9.19 88.9×6.45 141.3 1100 615 23 21 9-5/8

Steel grade:N80;
Thermal conductivity (inner wall of inner pipe 350℃): 0.002-0.08 W/m•℃;
Internal pressure strength:
Normal temperature: 32MPa;
Steam injection: 20MPa;
Flatness: ≤0.2%;
Well depth:≤1500m;
Working temperature:
Regular condition: 350℃
Over heating (3-4h): 380℃
Specification of Supercritical Vacuum insulated tubing

  OD × ID OD: Outer diameter ID: Inner diameter Basic Parameters Tensile strength Collapse Resistance Cementing Casing
OD × wall Thickness ID × wall Thickness OD of coupling Connecting thread   Normal temperature Steam injection  
mm in mm mm mm kN MPa MPa in
1 88×50 3-1/2×1.996 88.9×6.45 60.32×4.83 108 3-1/2USS 432 50 37 5
2 114×62 4-1/2×2.441 114.3×6.88 73.02×5.51 127 4-1/2BC 600 50 37 7

Steel grade: P110;
Thermal conductivity (inner wall of inner pipe 350℃): 0.04 W/m•℃;
Internal pressure strength:</span>
Normal temperature: 50MPa;
Steam injection: 40MPa;
Flatness: ≤0.2%;
Well depth: ≤1400m;
Working temperature:
Regular condition: 390℃
Over heating (3-4h): 400℃