Pre-Stressed Vacuum Insulated Tubing for Thermal Recovery Wells

Description

Goldenman Vacuum Insulated Tubing provides a high-efficiency thermal barrier for steam injection, heavy-oil recovery, geothermal production and temperature-sensitive oil and gas wells.

Each VIT joint uses a concentric double-wall structure consisting of:

• An inner fluid-carrying tube
• An outer mechanical protection tube
• A sealed high-vacuum annulus
• Multi-layer reflective insulation
• Silica, fiberglass or aerogel insulation
• Hydrogen and active-gas getter materials
• Pre-stressed inner-tube construction
• Insulated connection and coupling components
• High-temperature end seals and welded closures

The vacuum annulus minimizes convection. Multi-layer insulation reduces radiation. Low-conductivity supports and insulated connections limit solid conduction through the assembly.

Goldenman supplies Vacuum Insulated Tubing from 2-7/8 × 1.900 in to 7 × 5-1/2 in, with apparent thermal conductivity from 0.002 to 0.04 W/(m·K) and continuous operating temperatures up to 350°C / 662°F.

The product range supports:

• Cyclic Steam Stimulation
• Steam-Assisted Gravity Drainage
• Steam flooding
• Heavy-oil thermal recovery
• Geothermal injection and production
• High-pour-point crude production
• Paraffin and wax control
• Offshore high-temperature production
• Cold-region and permafrost protection
• Deepwater flow-assurance systems

Product Short Description

Goldenman Pre-Stressed Vacuum Insulated Tubing uses API 5CT steel tubulars combined with a sealed high-vacuum, multi-layer insulation system.

The pre-stressed inner tube compensates for differential thermal expansion between the hot flow tube and the cooler outer tube. The vacuum annulus, reflective layers and getter system reduce heat loss while maintaining steam quality and protecting surrounding casing, cement and formations from unnecessary thermal exposure.

Available configurations cover C, D and E insulation grades, J55, N80, L80 and P110 tubular materials, R2 and R3 lengths, API Buttress connections, USS connections and premium metal-to-metal connections.

Product Highlights

• Concentric double-wall VIT construction
• API 5CT inner and outer tubular materials
• Sizes from 2-7/8 × 1.900 to 7 × 5-1/2 in
• C, D and E thermal-insulation grades
• Apparent thermal conductivity as low as 0.002 W/(m·K)
• Continuous operating temperature up to 350°C
• Maximum temperature configuration up to 380°C
• Available operating pressure up to 35 MPa / 5,000 psi
• Running-depth configurations up to 1,500 m
• Pre-stressed inner flow tube
• High-vacuum sealed annulus
• Multi-layer reflective insulation
• Silica, fiberglass and aerogel options
• Distributed getter for long-term vacuum retention
• Insulated coupling and connection system
• Full-bore inner flow passage
• J55, N80, L80 and P110 steel grades
• API BTC, tubing and premium connections
• R2 and R3 joint lengths
• Standard and corrosion-resistant configurations
• Reusable thermal-recovery tubing
• Up to 30 CSS operating cycles
• 100% joint thermal-conductivity testing
• Weld RT, UT and magnetic-particle inspection
• Hydrostatic and drift testing
• Full material and joint traceability

General Technical Specifications

Parameter	Available Range
Product	Pre-Stressed Vacuum Insulated Tubing
Abbreviation	VIT
Basic construction	Concentric inner and outer steel tubes
Tubular material standard	API Spec 5CT
Connection dimensions	API Spec 5B or approved premium connection
Nominal configurations	2-7/8 × 1.900 in to 7 × 5-1/2 in
Insulation grades	C, D and E
Apparent thermal conductivity	0.002–0.04 W/(m·K)
Continuous operating temperature	Up to 350°C / 662°F
Maximum temperature	Up to 380°C / 716°F
Available operating pressure	Up to 35 MPa / 5,000 psi
Running depth	Up to 1,500 m / 4,921 ft
Outer-tube grades	J55, N80, L80 and P110
Inner-tube grades	J55, N80, L80 and P110
Joint lengths	API Range 2 and Range 3
Insulation materials	Silica, fiberglass, aerogel and reflective foil
Annulus condition	High vacuum with getter material
Inner-tube condition	Mechanically pre-stressed
Connection types	BTC, USS, API tubing and premium connections
Service	Steam injection, geothermal and insulated production
Testing	Thermal, hydrostatic, vacuum, weld, dimensional and drift tests
Documentation	MTR, NDE, pressure-test and thermal-test records

Standard Size Range

VIT Configuration	Outer Assembly OD	Inner Flow Bore ID	Minimum Drift	Unit Weight	Reference Tensile Load
2-7/8 × 1.900 in	73.0 mm	40.9 mm	38.52 mm	15 kg/m	370 kN
3-1/2 × 2-3/8 in	88.9 mm	50.6 mm	48.28 mm	21 kg/m	500 kN
4-1/2 × 2-7/8 in	114.3 mm	62.0 mm	59.62 mm	28 kg/m	600 kN
4-1/2 × 3-1/2 in	114.3 mm	76.0 mm	72.82 mm	32 kg/m	680 kN
5-1/2 × 4-1/2 in	139.7 mm	101.6 mm	98.42 mm	43 kg/m	780 kN
7 × 5-1/2 in	177.8 mm	124.0 mm	121.08 mm	62 kg/m	780 kN

Additional configurations include:

• 5 × 3-1/2 in
• Custom outer and inner tube combinations
• Increased-wall inner flow tubes
• Increased-collapse outer tubes
• Premium-connection VIT
• High-temperature geothermal VIT
• Project-specific high-pressure VIT

Standard Connection Range

VIT Configuration	Standard Connection Options
2-7/8 × 1.900 in	2-7/8 TBG, USS or premium connection
3-1/2 × 2-3/8 in	2-7/8 USS, integral or premium connection
4-1/2 × 2-7/8 in	3-1/2 USS, BTC or premium connection
4-1/2 × 3-1/2 in	4-1/2 BTC, integral or premium connection
5 × 3-1/2 in	5 BTC or premium connection
5-1/2 × 4-1/2 in	5-1/2 BTC or premium connection
7 × 5-1/2 in	7 BTC or premium connection

Connection arrangements include:

• External insulated coupling
• Internal insulated connection
• Flush-OD integral connection
• API Buttress Thread connection
• API tubing connection
• USS thermal-service connection
• Semi-premium connection
• Gas-tight premium metal-to-metal connection

Thermal Insulation Grades

Grade C Vacuum Insulated Tubing

Grade C has an apparent thermal-conductivity range of:

0.02 ≤ λ < 0.04 W/(m·K)

Grade C is used for:

• Moderate-temperature fluid transport
• High-pour-point crude production
• Wax-control applications
• Medium-depth geothermal wells
• Projects balancing thermal performance and acquisition cost
• Production strings requiring controlled heat retention

Grade D Vacuum Insulated Tubing

Grade D has an apparent thermal-conductivity range of:

0.006 ≤ λ < 0.02 W/(m·K)

Grade D is used for:

• Conventional CSS steam injection
• Steam flooding
• Heavy-oil thermal recovery
• Geothermal wells
• High-temperature production
• Repeated thermal cycling
• Medium- and deep-injection strings

Grade E Vacuum Insulated Tubing

Grade E has an apparent thermal-conductivity range of:

0.002 ≤ λ < 0.006 W/(m·K)

Grade E provides the highest insulation performance in the standard VIT range.

It is used for:

• SAGD steam-injection wells
• Deep CSS wells
• High steam-quality requirements
• High-temperature geothermal production
• Long thermal flow paths
• High fuel-cost projects
• Wells requiring maximum protection of casing and cement
• Environmentally sensitive thermal-recovery operations

Insulation Grade Comparison

Insulation Grade	Apparent Thermal Conductivity	Thermal Performance	Main Application
C	0.02–0.04 W/(m·K)	Standard	Heated production and moderate thermal retention
D	0.006–0.02 W/(m·K)	High	CSS, steam flooding and geothermal wells
E	0.002–0.006 W/(m·K)	Ultra-high	SAGD, deep steam injection and severe thermal service

A lower thermal-conductivity value represents lower heat transfer through the VIT assembly.

VIT Structure

Inner Flow Tube

The inner tube carries:

• High-temperature steam
• Hot water
• Geothermal brine
• Produced heavy oil
• Heated hydrocarbons
• Injection fluids

The inner tube provides the primary internal pressure boundary and flow passage.

Available inner-tube materials include:

• J55
• N80 Type 1
• N80Q
• L80 Type 1
• P110
• Corrosion-resistant alloy configurations

The inner tube is selected for pressure, axial load, temperature, fluid chemistry and connection performance.

Outer Protection Tube

The outer tube:

• Protects the vacuum annulus
• Carries external handling loads
• Supports the insulated connection
• Resists casing contact
• Protects internal insulation layers
• Provides external collapse resistance
• Transfers string tension through the connection

Available outer-tube grades include J55, N80, L80 and P110.

The outer-tube OD controls casing clearance and coupling-envelope requirements.

Vacuum Annulus

The annular space between the inner and outer tubes is evacuated to create a high-vacuum environment.

The vacuum reduces gaseous conduction and convection between the hot inner tube and the outer protective tube.

The annulus contains:

• Reflective foil
• Silica insulation
• Fiberglass insulation
• Aerogel
• Low-conductivity spacers
• Getter material
• Vacuum-monitoring and sealing components

Multi-Layer Insulation

Multi-layer insulation reduces radiative heat transfer.

The insulation package uses alternating layers of:

• Aluminum reflective foil
• Fiberglass
• Silica-based insulation
• Aerogel
• High-temperature separator material

The layers remain evenly distributed along the joint body and isolated from the inner flow bore.

Getter System

Getter materials absorb active gases released by metallic surfaces, insulation materials and weld areas during long-term high-temperature operation.

The getter system controls:

• Hydrogen
• Oxygen
• Nitrogen
• Water vapor
• Residual process gases
• Long-term material outgassing

Distributed getter placement maintains vacuum performance throughout the joint.

Insulated Connection

The connection area represents the shortest thermal path between the inner and outer tubes.

Goldenman insulated connections use:

• Thermal-barrier sleeves
• Low-conductivity inserts
• Extended heat-flow paths
• Metal-to-metal sealing
• Insulated coupling cavities
• High-temperature seal materials
• Controlled contact areas

The connection design reduces heat loss at each tubing joint while maintaining axial, pressure and torsional capacity.

Pre-Stressed Inner Tube

The inner and outer tubes experience different temperature increases during steam injection.

Without compensation, the hotter inner tube expands more than the outer tube. This creates compressive stress, connection loading, weld stress and possible inner-tube instability.

Goldenman VIT uses a mechanically pre-stressed inner tube.

During manufacturing:

1. The inner tube is placed under controlled axial tension.
2. The outer tube remains at its controlled assembly length.
3. The inner and outer tubes are joined and sealed.
4. The initial tensile preload remains in the inner tube at ambient temperature.
5. High operating temperature causes the inner tube to expand.
6. Thermal expansion progressively releases the initial tensile preload.
7. Compressive thermal stress remains controlled during operation.

The pre-stressed structure provides:

• Reduced thermal buckling
• Reduced end-weld loading
• Controlled differential expansion
• Improved connection stability
• Improved performance during repeated steam cycles
• Stable inner-bore alignment
• Extended insulation-system life

Thermal Performance

VIT reduces heat transfer by controlling all three primary heat-transfer mechanisms.

Conduction Control

Low-conductivity insulation, minimized metallic bridges and insulated connections reduce solid conduction between the inner and outer tubes.

Convection Control

The evacuated annular space contains very little gas, preventing normal convective circulation between the two tubular walls.

Radiation Control

Reflective foil and multi-layer barriers reflect thermal radiation back toward the inner flow tube.

The combined system maintains:

• Higher steam temperature
• Higher steam quality
• Lower condensation rate
• Greater effective injection depth
• More uniform heat delivery
• Reduced surface fuel consumption
• Reduced heat exposure to casing and cement

Steam Quality Retention

Steam loses quality as heat escapes through conventional tubing.

Condensed water increases while the dry-steam fraction falls, reducing the amount of usable thermal energy delivered to the formation.

Goldenman VIT reduces wellbore heat loss and supports:

• Higher bottomhole steam quality
• Greater steam-injection depth
• Faster reservoir heating
• Improved heat distribution
• Reduced water condensation
• Reduced steam-generation demand
• Improved thermal-recovery efficiency

CSS Applications

Cyclic Steam Stimulation consists of:

1. Steam injection
2. Soaking
3. Heavy-oil production
4. Repetition of the operating cycle

The VIT string experiences repeated heating and cooling during each cycle.

Goldenman pre-stressed construction accommodates thermal movement and maintains insulation performance through repeated CSS operation.

The insulation system is designed for up to 30 huff-and-puff cycles under the specified operating program.

SAGD Applications

Steam-Assisted Gravity Drainage uses a horizontal steam-injection well positioned above a production well.

VIT is installed in the injection string to:

• Maintain steam temperature
• Deliver high-quality steam to the horizontal section
• Reduce heat loss in the vertical and build sections
• Limit casing and cement exposure
• Improve steam distribution
• Reduce surface energy consumption
• Support stable chamber development

Grade E VIT provides maximum thermal retention for long SAGD injection strings.

Steam-Flooding Applications

Steam flooding continuously injects steam through selected wells to drive heated oil toward production wells.

VIT supports:

• Continuous high-temperature operation
• Reduced heat loss through the injection string
• Stable steam quality
• Increased effective injection depth
• Controlled casing temperature
• Long-term thermal-recovery programs

Heavy-Oil Production

VIT is also used as an insulated production string.

It maintains fluid temperature and reduces:

• Crude-oil viscosity increase
• Paraffin deposition
• Wax accumulation
• Flow restriction
• Restart pressure after shutdown
• Chemical and mechanical cleaning frequency

Insulated production tubing is used for high-pour-point crude, wax-prone oil and temperature-sensitive heavy-oil production.

Geothermal Applications

In geothermal wells, produced-fluid temperature directly affects power-generation and heating efficiency.

VIT reduces temperature loss in:

• Geothermal production wells
• Geothermal injection wells
• Hot-water wells
• Steam-production wells
• District-heating systems
• High-temperature brine systems

The inner tube is supplied with corrosion-resistant materials and premium connections for hot brine, chlorides and dissolved gases.

Offshore and Deepwater Applications

VIT supports offshore temperature control by reducing heat loss from produced fluids.

Applications include:

• High-temperature offshore wells
• Wax-sensitive production
• Hydrate-control systems
• Extended shut-in periods
• Deepwater production riser interfaces
• Environmentally sensitive offshore fields

The thermal barrier helps maintain flow temperature and reduces the cooling rate during production interruption.

Cold-Region Applications

In Arctic and permafrost areas, VIT reduces heat transfer from hot production or injection fluids into the surrounding formation.

This protects:

• Permafrost stability
• Wellhead foundations
• Cement systems
• Surface casing
• Near-surface formations
• Environmental conditions around the well

Steel Grade Selection

J55

J55 is used for:

• Moderate-depth thermal wells
• Lower axial loads
• Standard non-sour service
• Economical outer-tube construction

N80

N80 and N80Q provide increased strength for:

• Medium-depth injection wells
• Higher string tension
• Repeated thermal cycling
• Medium-pressure steam service
• Heavy-oil production

L80

L80 provides controlled strength and hardness for:

• Thermal-recovery wells
• Corrosion-controlled service
• Geothermal applications
• H₂S-containing environments
• High-temperature production

P110

P110 provides high tensile capacity for:

• Deep VIT strings
• High suspended loads
• Increased injection pressure
• Large-diameter VIT
• High-strength outer and inner tubes

The inner and outer tubes can use different grades to balance pressure capacity, axial load, corrosion resistance and total cost.

Connection Selection

Buttress Thread Connection

BTC connections provide:

• High axial-load transfer
• Strong casing-style connection
• Reliable large-diameter VIT assembly
• Compatibility with 4-1/2–7 in outer tubes
• Efficient field makeup

USS Thermal-Service Connection

USS connections provide:

• Compact OD
• Insulated connection geometry
• High axial capacity
• Controlled thermal transfer
• Full-bore inner flow path
• Repeated thermal-cycle resistance

API Tubing Connection

API tubing connections are used in smaller VIT sizes and production applications.

Available types include:

• EUE
• NUE
• Project-specific tubing connections

Premium Metal-to-Metal Connection

Premium connections provide:

• Gas-tight metal-to-metal sealing
• High-temperature sealability
• Increased tension and compression capacity
• Improved repeated makeup performance
• Reduced connection heat loss
• High-pressure geothermal and steam service

Length Options

Goldenman supplies:

• API Range 2 joints
• API Range 3 joints
• 8 m joints
• 9.5 m joints
• 10 m joints
• 12 m joints
• Custom project lengths

Longer joints reduce the number of connections and lower total connection heat loss within the string.

VIT Selection Guide

The VIT configuration is selected from:

• Well depth
• Injection depth
• Steam temperature
• Steam pressure
• Required bottomhole steam quality
• Injection rate
• Production-fluid temperature
• Inner flow-area requirement
• Casing ID
• Maximum connection OD
• Suspended tubing load
• Thermal-cycle count
• H₂S concentration
• CO₂ concentration
• Chloride concentration
• Connection type
• Insulation grade
• Maximum allowable heat loss

Manufacturing Process

Goldenman VIT manufacturing includes:

1. API 5CT inner- and outer-tube verification
2. Heat-number and joint-number assignment
3. Chemical and mechanical-property inspection
4. Full-body pipe NDE
5. Dimensional and straightness inspection
6. Inner-tube surface preparation
7. Multi-layer insulation installation
8. Getter placement
9. Concentric inner- and outer-tube assembly
10. Controlled inner-tube pre-stressing
11. End-component installation
12. Automatic pressure-boundary welding
13. Weld radiographic or ultrasonic inspection
14. Vacuum bakeout
15. Multi-stage annulus evacuation
16. Getter activation
17. Vacuum sealing
18. Connection machining
19. Thread gauging
20. Drift testing
21. Hydrostatic testing
22. Thermal-conductivity testing
23. External coating
24. Permanent marking
25. Thread-protector installation
26. Final documentation review
27. Export packaging

Vacuum and Weld Control

Long-term insulation performance depends on the integrity of the vacuum annulus.

Quality control includes:

• Vacuum-port inspection
• End-weld inspection
• Helium leak testing
• Pressure-rise testing
• Residual-gas control
• Getter activation
• Bakeout-temperature control
• Vacuum-hold verification
• Weld RT or UT
• Weld-surface MPI
• Final thermal-performance testing

Every joint receives an individual serial number linking its vacuum, weld and thermal test records.

Thermal-Conductivity Testing

Each VIT joint undergoes thermal-performance testing.

The test determines:

• Apparent thermal conductivity
• Insulation grade
• Temperature distribution
• Connection heat loss
• Vacuum-system stability
• Consistency along the pipe body

The final test report identifies:

• Joint serial number
• Test temperature
• Test duration
• Measured conductivity
• Assigned insulation grade
• Acceptance result

Mechanical and Pressure Testing

Testing includes:

• Inner-tube hydrostatic test
• Pressure-boundary test
• Outer-tube dimensional inspection
• Axial tensile verification
• Connection makeup test
• Drift test
• Straightness inspection
• Wall-thickness inspection
• Weld NDE
• Vacuum integrity test
• Final visual inspection

Installation

Installation procedure:

1. Verify VIT size, grade and insulation class.
2. Confirm the running order and tally.
3. Inspect the outer tube for transport damage.
4. Inspect both connections and sealing areas.
5. Remove the thread protectors.
6. Clean and dry the connections.
7. Apply the approved high-temperature thread compound.
8. Align the joints vertically.
9. Start the connection by hand.
10. Apply controlled makeup torque or position.
11. Avoid gripping or crushing the insulated body.
12. Use elevators and slips matched to the outer-tube OD.
13. Record the joint serial number and installed depth.
14. Install centralizers and protectors at specified locations.
15. Complete the tubing-string pressure test.
16. Begin controlled heating according to the steam-injection program.

The VIT body is not used as the tong gripping area unless the marked handling zone is designed for that purpose.

Handling and Storage

VIT requires controlled handling to protect its vacuum system and concentric structure.

Handling requirements include:

• Use of padded lifting equipment
• Multiple lifting support points
• No uncontrolled dropping
• No impact on end welds
• No chain contact with the pipe body
• No gripping outside marked handling areas
• Installed thread protectors
• Level storage racks
• Separation by size and grade
• Protection from standing water
• Clear joint-number identification

Common Failure Modes

Vacuum Degradation

Vacuum loss results from:

• End-weld leakage
• Vacuum-port leakage
• Hydrogen permeation
• Getter saturation
• Mechanical impact
• Thermal fatigue
• Long-term material outgassing

Vacuum degradation increases apparent thermal conductivity and external tube temperature.

Connection Heat Loss

Excessive connection heat loss results from:

• Incorrect insulated coupling
• Missing thermal sleeve
• Damaged insulation insert
• Incorrect connection makeup
• Metal bridging
• Repeated connection damage

Inner-Tube Thermal Buckling

Thermal buckling results from:

• Insufficient pre-stress
• Excessive operating temperature
• Incorrect string restraint
• Rapid uncontrolled heating
• Damaged end connections
• Incorrect well design

Annulus Moisture Entry

Moisture entering the vacuum annulus damages insulation performance and promotes internal corrosion.

External Mechanical Damage

Dents, bending and end impact can damage:

• The outer tube
• Internal supports
• Vacuum seals
• Insulation layers
• End welds
• Connection alignment

Connection Leakage

Connection leakage results from:

• Incorrect thread compound
• Insufficient makeup
• Excessive makeup
• Thread galling
• Seal damage
• Mismatched connections
• Thermal cycling outside the design envelope

Inspection During Workover

Recovered VIT is inspected for:

• External dents
• Bending
• Connection damage
• Thread wear
• End-weld cracks
• Corrosion
• Outer-tube wear
• Abnormal surface discoloration
• Increased external temperature
• Loss of vacuum performance
• Reduced thermal grade

Reusable joints undergo:

• Visual inspection
• Dimensional inspection
• Thread inspection
• NDE
• Hydrostatic testing
• Vacuum-integrity testing
• Thermal-conductivity retesting

Product Marking

Each VIT joint is marked with:

• Goldenman identification
• VIT configuration
• Outer- and inner-tube grades
• Insulation grade
• Connection type
• Joint length
• Heat numbers
• Joint serial number
• Manufacturing date
• Thermal-test result
• Maximum operating temperature

Product Documentation

The documentation package includes:

• Certificate of Conformity
• Product datasheet
• VIT cross-section drawing
• Connection drawing
• API 5CT material certificates
• EN 10204 3.1 certificates
• Chemical-composition reports
• Mechanical-property reports
• Heat-treatment records
• Inner- and outer-tube NDE reports
• Weld RT or UT reports
• Weld MPI reports
• Hydrostatic-test reports
• Vacuum-integrity report
• Helium leak-test report
• Thermal-conductivity report for each joint
• Thread-gauge inspection report
• Drift inspection report
• Dimensional inspection report
• Joint traceability list
• Running and handling manual
• Packing list
• Third-party inspection report

Frequently Asked Questions

What is Vacuum Insulated Tubing?

Vacuum Insulated Tubing is a concentric double-wall tubular product with a high-vacuum and multi-layer insulation system between the inner and outer tubes.

It reduces heat transfer between the flowing fluid and the surrounding wellbore.

What sizes are available?

The standard range includes:

• 2-7/8 × 1.900 in
• 3-1/2 × 2-3/8 in
• 4-1/2 × 2-7/8 in
• 4-1/2 × 3-1/2 in
• 5-1/2 × 4-1/2 in
• 7 × 5-1/2 in

A 5 × 3-1/2-inch configuration and custom sizes are also available.

What do the two sizes mean?

The first value identifies the outer assembly size.

The second value identifies the inner flow-tube size or corresponding internal flow configuration.

The final bore and drift diameter are defined in the technical table.

What insulation grades are available?

Goldenman supplies Grade C, Grade D and Grade E VIT.

Grade E has the lowest apparent thermal conductivity and the highest standard insulation performance.

What is the lowest thermal-conductivity value?

Grade E VIT reaches an apparent thermal conductivity as low as 0.002 W/(m·K).

What is the maximum operating temperature?

Continuous operating configurations are available up to 350°C, with maximum-temperature configurations up to 380°C.

Which steel grades are available?

Available API 5CT grades include:

• J55
• N80
• L80
• P110

The inner and outer tubes can use different grades.

Why is the inner tube pre-stressed?

Pre-stressing compensates for the greater thermal expansion of the hot inner tube and reduces compressive stress during steam injection.

What is the purpose of the getter?

The getter absorbs hydrogen, water vapor and other active gases released inside the vacuum annulus, maintaining long-term vacuum performance.

Is API 5CT the thermal-insulation standard?

API 5CT defines the technical delivery requirements for the steel tubulars, grades, dimensions and applicable OCTG connections.

The vacuum annulus, insulation system, pre-stress and thermal-conductivity grade form the engineered VIT assembly specification.

Is VIT used only for steam injection?

No.

VIT is also used for geothermal wells, high-pour-point crude production, wax control, offshore high-temperature production and cold-region thermal protection.

Can VIT be reused?

Yes.

Recovered joints that pass dimensional, connection, pressure, vacuum and thermal-conductivity inspection can be returned to service.

What is the difference between Grade D and Grade E?

Grade D has apparent thermal conductivity from 0.006 to below 0.02 W/(m·K).

Grade E has apparent thermal conductivity from 0.002 to below 0.006 W/(m·K).

Are premium connections available?

Yes.

Goldenman supplies integral, semi-premium and premium metal-to-metal connections for high-temperature and high-pressure service.

How is every joint tested?

Each joint undergoes material inspection, weld NDE, vacuum-integrity testing, hydrostatic testing, thread inspection, drift testing and thermal-conductivity testing.

Information Required for Quotation

Please provide:

• VIT configuration
• Outer-tube OD and wall thickness
• Inner-tube OD and wall thickness
• Required inner bore
• Outer-tube steel grade
• Inner-tube steel grade
• Required insulation grade
• Maximum apparent thermal conductivity
• Joint length
• Range 2 or Range 3
• Connection type
• Premium-connection drawing
• Maximum operating pressure
• Steam-injection pressure
• Continuous operating temperature
• Maximum temperature
• Running depth
• Suspended string load
• CSS, SAGD or geothermal application
• Injection-fluid composition
• H₂S concentration
• CO₂ concentration
• Chloride concentration
• Expected thermal-cycle quantity
• Casing ID and drift
• Maximum connection OD
• Internal coating
• External coating
• NDE requirements
• Thermal-test requirements
• Third-party inspection
• Documentation requirements
• Required quantity
• Destination country
• Delivery schedule

Request a Technical Quotation

Goldenman supplies Pre-Stressed Vacuum Insulated Tubing for CSS, SAGD, steam flooding, geothermal production, heavy-oil recovery and temperature-sensitive production wells.

The complete range covers:

• 2-7/8 × 1.900 to 7 × 5-1/2-inch configurations
• C, D and E insulation grades
• Apparent thermal conductivity down to 0.002 W/(m·K)
• J55, N80, L80 and P110 steel grades
• API BTC, USS and premium connections
• R2, R3 and custom joint lengths
• Operating temperatures up to 350°C
• High-temperature configurations up to 380°C

Each joint is supplied with material traceability, weld NDE, hydrostatic testing, vacuum-integrity verification and an individual thermal-conductivity test report.

Email: info@goldenman.com