- Prevention of wellbore thawing in permafrost zones

- Prevention of formation of gas hydrates, asphalt, resin, and paraffin depositions

Type of thermal insulation

Design features

Performance specifications

Since 2010

Vacuum Insulated Tubing

Vacuum shield thermal pipe insulation

In accordance with the design, a shield of foil and basalt fiber fabric (together with gas absorbers) is installed in the annular space.

Vacuum is created in the annular space. A fluoroplastic coupling insert is placed inside the coupling.

"Pre-stressing" of the internal pipe is performed in the VIT designed for operation at high temperatures. 

Operating temperature: up to +350^°С

Operating pressure: up to 16MPa

Thermal conductivity (K-factor) along the pipe body, W/(m*K): up to 0.012 (+220°С), up to 0.02 (+350°С)

Thermal conductivity (K-factor) of the fluoroplastic coupling insert, W/(m*K): up to 0.25

The pipes are used for the following:

- Prevention of wellbore thawing in permafrost zones

- Prevention of formation of gas hydrates, asphalt, resin, and paraffin depositions

Injection of superheated fluids into the reservoir in order to heat up high-viscosity oils during development by cyclic steam heating methods (including such as CSS and SAGD)

Since 2015

Non-Vacuum Insulated Tubing

Insulation with inorganic thermal insulation materials

In accordance with the design, a shield of foil and basalt fiber fabric is installed in the annular space. A fluoroplastic coupling insert is placed inside the coupling.

The design was developed with account of additional requirements of our customers – oil companies.

Operating temperature: up to +180^°С

Operating pressure: up to 16MPa

Thermal conductivity (K-factor) along the pipe body, W/(m*K): up to 0.03 (+50^°С), up to 0.06 (+180^°С)

Thermal conductivity (K-factor) of the fluoroplastic coupling insert, W/(m*K): up to 0.25

The pipes are used for the following:

- Prevention of wellbore thawing in permafrost zones

- Injection of superheated fluids into the reservoir in order to heat up high-viscosity oils during development by cyclic steam heating methods (including such as CSS and SAGD)

- Prevention of formation of gas hydrates, asphalt, resin, and paraffin depositions

Performance parameters

Limit value

Operating temperature, °С

up to +350

String length, max

determined by calculation and depends on the type of threaded connection

Thermal conductivity coefficient (k-factor) along the pipe body, max

see table below

Thermal conductivity coefficient (k-factor) of coupling insert, max, W/(m*K)

0.25

Technical parameters

Limit value

Residual air pressure in the annular space, max, mm Hg

8*10^-2 (6*10^-4)

Pipe length, m

10-11.7*

Weld seam requirements

The seams should be heat treated

Hydrotesting

VIT with made up couplings is subjected to hydrotesting at R = 0.8 σ_т

Grades

Carbon (55-95 ksi); 13Cr (80 ksi)

Charpy test

Not less than 50 J/cm² at -60°C

1 – External pipe

2 – Coupling

3 – Internal pipe

4 – Shield insulation

5 – Getter (gas absorber)

6 – Vacuum valve

7 – Coupling insert (fluoroplastic)

8 – Bowl protector

9 – Vacuum created in the annular space

10 – Connection element

11 – Stabilizing ring