Description
API 6A Tubing Head Spool for Oil, Gas, ESP & Injection Wellheads
SGPE manufactures and supplies API 6A Tubing Head Spools for oil and gas production, ESP artificial lift, water and gas injection, workover, recompletion and mature-field replacement projects.
Also known as a Tubing Spool, Production Tubing Head or Wellhead Tubing Head, this component sits in the upper section of a conventional surface wellhead. Its internal bowl receives the tubing hanger, supports tubing loads, maintains the tubing-casing annulus interface and connects the casing-support section to the upper completion or Christmas Tree equipment.
Project configurations can cover 2K, 3K, 5K, 10K and 15K working pressures, with API flanged or studded connections, API 6B or API 6BX interfaces where applicable, conventional or extended-neck tubing hangers, ESP electrical feed-throughs, SCSSV control lines, single- or dual-string completions, side outlets and sour-service requirements.
SGPE also supports High Pressure, Forged, ESP, Offshore, Injection, H2S, Custom and Replacement API 6A Tubing Head Spools.
For a new wellhead RFQ, provide the casing program, tubing program, working pressure, completion design and mating interfaces. For replacement projects, drawings, nameplates, RTJ details, tubing-hanger information, verified dimensions and field photographs help confirm compatibility.
Product Short Description
The SGPE API 6A Tubing Head Spool provides the pressure-containing housing and tubing-hanger interface between the casing-support section of a wellhead and the upper production, injection or Christmas Tree equipment.
Available project configurations can cover 2,000 to 15,000 psi, API flanged or studded connections, API 6B or API 6BX interfaces where applicable, conventional and extended-neck tubing hangers, ESP electrical penetrators, SCSSV control lines, single- and dual-string completions, annulus side outlets and sour-service requirements.
Common tubing programs can involve 2-3/8″, 2-7/8″, 3-1/2″ and 4-1/2″ production or injection tubing, subject to the approved tubing-hanger and completion design.
The Tubing Head Spool can be supplied individually or coordinated with the Casing Spool, Tubing Hanger, Tubing Head Adapter, API 6A Gate Valves and Wellhead Christmas Tree for new wellheads, ESP conversions, injection projects, workover programs and replacement applications.
API 6A Tubing Head Spool Product Overview
An API 6A Tubing Head Spool forms the transition between the casing-support section of a conventional surface wellhead and the production or injection tubing system above it.
The Casing Head and Casing Spools support casing strings. The Tubing Head Spool performs a different function. Its internal bowl receives the tubing hanger, while the hanger supports the production or injection tubing and transfers the suspended load into the wellhead structure.
The spool also forms part of the pressure-containing wellhead and provides controlled access to the tubing-casing annulus.
Its lower connection normally matches a Casing Spool or Casing Head. During completion or workover, the upper connection may interface with pressure-control equipment. During production, it normally connects toward the Tubing Head Adapter and Christmas Tree.
Because several critical interfaces meet at this component, a Wellhead Tubing Spool should not be selected only by nominal flange size or working pressure.
A reliable selection also considers the tubing-hanger profile, internal bore, RTJ interface, side-outlet arrangement, suspended tubing load, overall stack height, operating temperature, well fluid, material requirements and completion feed-throughs.
This becomes particularly important when purchasing 10K or 15K Tubing Head Spools, ESP wellhead equipment, offshore SCSSV completions, high-pressure gas wellheads, injection wellheads, dual-string completions, sour-service equipment or replacement wellhead components.
API 6A Tubing Head Spool Technical Specifications
API 6A Tubing Head Spool Core Specifications & Interfaces
The following specifications provide a practical reference for API 6A Tubing Head Spool selection, datasheet preparation and RFQ review. Final dimensions and interfaces depend on the approved manufacturing drawing, mating wellhead equipment and project requirements.
| Technical Parameter | Typical Range / Configuration | Main Selection Basis |
|---|---|---|
| Product | API 6A Tubing Head Spool | Wellhead configuration |
| Alternative Names | Tubing Spool, Production Tubing Head, Wellhead Tubing Head | Project terminology |
| Main Standard | Applicable API Spec 6A and approved project requirements | Purchase specification |
| Main Function | Tubing-hanger landing, tubing suspension and annulus containment | Completion program |
| Rated Working Pressure | 2,000 / 3,000 / 5,000 / 10,000 / 15,000 psi | Required wellhead pressure |
| Metric Pressure Reference | 13.8 / 20.7 / 34.5 / 69.0 / 103.5 MPa | Pressure class |
| Common Wellhead Interfaces | Project-specific; RFQs may involve 7-1/16″, 9″, 11″ and 13-5/8″ | Mating equipment |
| Common Tubing Programs | 2-3/8″, 2-7/8″, 3-1/2″, 4-1/2″ | Completion design |
| Upper Connection | API flanged or studded | Adapter, BOP or Christmas Tree |
| Lower Connection | API flanged or studded | Casing Head or Casing Spool |
| Connection Family | API 6B / API 6BX where applicable | Size and pressure |
| RTJ Ring Groove | Matched to approved mating connection | Flange specification |
| Internal Bore | Project-specific | Hanger and completion tools |
| Tubing-Hanger Bowl | Matched to approved hanger | Landing and sealing profile |
| Overall Height | Drawing-specific | Wellhead stack |
API 6A Tubing Head Spool Configuration, Service & Quality Options
Tubing Head Spool configuration also depends on the completion type, operating environment, material requirements and inspection scope. ESP, SCSSV, dual-string and sour-service projects may require additional interfaces or material controls.
| Technical Parameter | Typical Range / Configuration | Main Selection Basis |
|---|---|---|
| Tubing Hanger Options | Mandrel, slip-type, extended-neck, ESP, control-line, single- or dual-string | Completion type |
| Body Construction | Forged alloy steel or approved project construction | Pressure and service |
| Material Class | According to applicable API 6A and project requirements | Well fluid and corrosion |
| Temperature Requirement | API 6A temperature class or project-defined range | Operating conditions |
| SGPE Temperature Reference | Approx. -46°C to +121°C where approved configuration supports it | Final project confirmation |
| PSL | According to applicable API 6A pressure/material combination | Quality scope |
| Sour-Service Option | Project-specific material and hardness control | H2S / CO2 service |
| Primary Sealing | Metal and/or elastomeric system | Pressure, temperature and fluid |
| Hanger Retention | Lockdown screws or design-specific retention | Hanger configuration |
| Side Outlets | Flanged, studded or threaded project-specific arrangement | Annulus access |
| ESP Interface | Tubing hanger with electrical feed-through | ESP completion |
| SCSSV Interface | Hydraulic control-line tubing hanger | Safety-valve completion |
| Chemical / Monitoring Feed-Through | Project-specific | Completion design |
| Dual-String Option | Matched dual-bore hanger and tree | Dual-zone completion |
| Inspection / NDE | According to approved quality scope | ITP / specification |
| Pressure Testing | According to applicable approved requirements | Test procedure |
| Documentation | Material, NDE and test records as specified | Contract scope |
| Supply Scope | Individual spool or matched wellhead package | RFQ |
Selection Note: Not every size, pressure rating, material class, PSL, tubing hanger and connection combination forms a standard product. The complete wellhead interfaces determine the final configuration.
API 6A Tubing Head Spool Pressure Ratings
Working pressure influences the body design, connections, sealing arrangement, material requirements and mating equipment.
| Pressure Class | Rated Working Pressure | Metric Reference | Typical Project Focus |
|---|---|---|---|
| 2K Tubing Head Spool | 2,000 psi | 13.8 MPa | Lower-pressure production or injection |
| 3K Tubing Head Spool | 3,000 psi | 20.7 MPa | Conventional production and replacement |
| 5K Tubing Head Spool | 5,000 psi | 34.5 MPa | Oil production, ESP, injection and workover |
| 10K Tubing Head Spool | 10,000 psi | 69.0 MPa | High-pressure oil and natural gas wells |
| 15K Tubing Head Spool | 15,000 psi | 103.5 MPa | High-pressure gas and demanding completion service |
A pressure rating alone does not define a complete High Pressure API 6A Tubing Head Spool.
For example, a 10K Tubing Head Spool quotation still requires the upper and lower connections, internal bore, RTJ interfaces, tubing-hanger profile, material requirements, operating temperature, PSL, side outlets and Christmas Tree interface.
The same principle applies to a 15K Tubing Head Spool. Every relevant pressure-containing component in the wellhead stack must remain compatible.
API 6A Tubing Head Spool Sizes, Flanges, RTJ and Connections
Buyers commonly search for an API 6A Tubing Head Spool size chart, Tubing Spool flange size, Tubing Head dimensions, 11 Inch Tubing Head Spool, 13-5/8 Tubing Head, RTJ Tubing Head or Tubing Head drawing before preparing an RFQ.
Nominal size provides a useful starting point, but it does not define the complete product.
| RFQ Reference | Common Project Use | Additional Data Required |
|---|---|---|
| 7-1/16″ Wellhead Interface | Selected production and completion systems | Pressure, connections, bore and hanger |
| 9″ Wellhead Interface | Conventional wellhead systems | Pressure and mating equipment |
| 11″ Wellhead Interface | Conventional and compact wellheads | Pressure, bowl and flange arrangement |
| 13-5/8″ Wellhead Interface | Larger conventional wellhead systems | Mating spool, bore and pressure |
| 2-3/8″ Tubing | Production / artificial lift | Hanger and tubing connection |
| 2-7/8″ Tubing | Common production tubing | Hanger profile and suspended load |
| 3-1/2″ Tubing | Production, injection and artificial lift | Completion interface |
| 4-1/2″ Tubing | Larger production or injection tubing | Bore and hanger clearance |
These values serve as common RFQ references rather than a universal SGPE size matrix.
An 11 Inch 10K API 6A Tubing Head Spool quotation, for example, still requires the complete upper and lower connection designations, RTJ information, internal bore, tubing-hanger profile, side outlets and service conditions.
API 6A Tubing Head Spool Dimensions and Drawing Data
There is no universal set of API 6A Tubing Head Spool dimensions for every wellhead.
The final geometry depends on the mating equipment above, below and inside the spool.
| Interface Item | Information to Confirm | Why It Matters |
|---|---|---|
| Top Connection | Complete size, pressure and connection type | Matches adapter, BOP or tree |
| Bottom Connection | Complete size, pressure and connection type | Matches Casing Spool |
| Top / Bottom RTJ | Approved ring-groove interface | Pressure sealing |
| Internal Bore | Required minimum bore / drift | Completion-tool access |
| Tubing-Hanger Bowl | Hanger profile and dimensions | Correct hanger landing |
| Landing Shoulder | Geometry and design load | Tubing suspension |
| Hanger Seal Diameter | Approved sealing interface | Annulus integrity |
| Overall Height | Required or existing dimension | Stack and flowline alignment |
| Side-Outlet Size | Connection and pressure requirement | Valve compatibility |
| Outlet Orientation | Required angular position | Field piping |
| Lockdown Arrangement | Approved configuration | Hanger retention |
| Extended-Neck Interface | Hanger neck dimensions | Adapter sealing |
| ESP Feed-Through | Penetrator interface | ESP completion |
| SCSSV Lines | Quantity, size and pressure | Hydraulic control |
For a new wellhead project, SGPE can prepare a proposed API 6A Tubing Head Spool dimensional drawing after technical review.
For replacement work, the existing drawing provides the strongest reference. If it is unavailable, nameplate data, verified field measurements and clear photographs can help establish the required interfaces.
How an API 6A Tubing Head Spool Works
Tubing Hanger Landing and Suspension
The internal bowl provides the landing area for the tubing hanger. The hanger supports the production or injection tubing and transfers its suspended load into the wellhead structure.
Different tubing hangers use different landing shoulders, sealing profiles and internal geometry. The Tubing Head Spool and Tubing Hanger therefore need to operate as a matched interface.
Tubing-Casing Annulus Control
The tubing hanger, spool sealing areas and associated seals separate the tubing flow path from the tubing-casing annulus.
This function supports conventional production and becomes particularly important in high-pressure gas wells, ESP completions, injection projects and wells requiring long-term annulus monitoring.
Annulus Access Through Side Outlets
Side outlets provide controlled access to the tubing-casing annulus.
Wellhead valves, gauges, instruments or piping can connect to these outlets for pressure monitoring, testing, controlled bleed-off, circulation and other approved well operations.
Connection to the Christmas Tree and Upper Wellhead
The lower side of the Tubing Head Spool connects toward the casing-support section of the wellhead. The upper side connects toward the Tubing Head Adapter, temporary completion equipment or production Christmas Tree.
Correct flange, RTJ, bore and stack-height matching therefore affects both installation and system compatibility.
Forged API 6A Tubing Head Spool
A Forged API 6A Tubing Head Spool can suit projects where pressure integrity, material traceability and dimensional control are important.
Forged alloy-steel body configurations can be selected according to the required pressure class, well conditions and approved project specification.
Material selection should reflect the complete operating environment rather than only nominal working pressure. High-pressure natural gas, offshore applications and H2S-containing wells can require closer control of material properties, heat treatment, hardness, sealing interfaces, NDE and documentation.
API 6A PSL Reference by Pressure and Material Class
Product Specification Level does not function as an independent purchasing option. Pressure rating and material class influence the applicable PSL.
| Material Class | 2K | 3K | 5K | 10K | 15K |
|---|---|---|---|---|---|
| AA / BB / CC | PSL 1, 2, 3 or 4 | PSL 1, 2, 3 or 4 | PSL 1, 2, 3 or 4 | PSL 2, 3 or 4 | PSL 2, 3 or 4 |
| DD / EE / FF | PSL 1, 2, 3 or 4 | PSL 1, 2, 3 or 4 | PSL 1, 2, 3 or 4 | PSL 2, 3 or 4 | PSL 3 or 4 |
| HH / ZZ | PSL 3 or 4 | PSL 3 or 4 | PSL 3 or 4 | PSL 3 or 4 | PSL 3 or 4 |
Where applicable product and testing requirements allow it, a project may also include gas-testing requirements associated with PSL 3G.
This table provides a general API 6A selection reference. It does not mean that every SGPE Tubing Head Spool automatically covers every listed Material Class and PSL combination.
API 6A Tubing Head Spool Configurations
Conventional Production Tubing Head Spool
A Production Tubing Head Spool normally supports a single production tubing string through a compatible tubing hanger.
This configuration suits many conventional oil and natural gas wellheads. Selection typically centers on tubing size, working pressure, hanger profile, tubing load, Christmas Tree connection and annulus outlets.
10K and 15K High Pressure Tubing Head Spool
A 10K Tubing Head Spool or 15K Tubing Head Spool serves demanding high-pressure oil, gas and injection projects.
The body, API connections, RTJ grooves, tubing hanger, sealing system, materials and upper tree all need to operate together. Reviewing the complete wellhead stack therefore provides a stronger basis for quotation than pressure class alone.
ESP Tubing Head Spool
An ESP Tubing Head Spool works with a compatible ESP tubing hanger and electrical penetrator or cable feed-through.
The project should identify the tubing size, hanger design, penetrator, cable arrangement, working pressure, temperature, orientation and upper adapter.
These details become particularly important in ESP wellhead retrofit, ESP conversion and mature-field artificial-lift projects.
SCSSV Control-Line Tubing Head Spool
Selected offshore and high-integrity production wells use a Surface-Controlled Subsurface Safety Valve.
The tubing hanger then needs hydraulic control-line passages, while the Tubing Head Spool requires suitable internal clearance and orientation.
Some completion systems can also include chemical-injection or downhole-monitoring feed-throughs.
Extended-Neck and Dual-String Tubing Head Spools
An extended-neck tubing hanger reaches upward toward the Tubing Head Adapter. Its neck diameter, seal position and adapter interface need to match the spool geometry.
A Dual-String Tubing Head Spool works with a dual-bore tubing hanger and compatible dual-completion Christmas Tree. Bore spacing, orientation and sealing geometry therefore require coordinated design.
Flanged and Studded Tubing Head Spools
A Flanged Tubing Head Spool uses API flange interfaces according to the approved size and pressure class. Selected configurations can also use a studded upper or lower connection.
Because the top and bottom interfaces do not always share the same nominal size or pressure designation, both complete connections should be included in an API 6A Tubing Spool RFQ.
Sour Service and H2S Tubing Head Spools
A Sour Service API 6A Tubing Head Spool can require additional control of body material, hardness, sealing elements and inspection.
Actual H2S, CO2, temperature and well-fluid information provides a stronger basis for material selection than a generic request for an H2S-service Tubing Head.
API 6A Tubing Head Spool Applications
| Oilfield Application | Typical Configuration | Main Selection Focus |
|---|---|---|
| Onshore Oil Production | Production Tubing Head Spool | Tubing, pressure and tree |
| Offshore Oil & Gas Production | Offshore Tubing Head with feed-throughs | SCSSV, corrosion and documentation |
| Natural Gas Production | Production Tubing Spool | Gas pressure and sealing |
| High-Pressure Gas Well | 10K / 15K Tubing Head Spool | Pressure, material and sour service |
| ESP Artificial Lift | ESP Tubing Head Spool | Hanger and cable penetrator |
| Water Injection | Injection Tubing Head | Injection pressure and water chemistry |
| Gas Injection | High-Pressure Injection Tubing Spool | Gas pressure and material |
| Dual-Zone Completion | Dual-String Tubing Head | Bore spacing and orientation |
| SCSSV Completion | Control-Line Tubing Head | Hydraulic feed-through |
| Workover / Recompletion | Existing lower wellhead with revised completion | Interface compatibility |
| Mature-Field MRO | Replacement Tubing Head Spool | Existing dimensions |
| Christmas Tree Upgrade | Retained lower wellhead | Upper interface and stack height |
| Sour Gas Production | H2S Service Tubing Head | Material and hardness |
The application affects far more than the product name.
A conventional 5K oil well may use a straightforward single-string hanger, while a 5K ESP well adds an electrical penetrator. Offshore completions can introduce SCSSV hydraulic lines, monitoring feed-throughs and additional documentation requirements.
High-pressure gas wells may use 10K or 15K Tubing Head Spools, where pressure, temperature, gas composition, sealing and material requirements require coordinated review. Water- and gas-injection wells introduce different fluid, corrosion and injection-tree considerations.
For this reason, well application should accompany size and pressure information in every serious API 6A Tubing Head Spool RFQ.
Tubing Head Spool and Tubing Hanger Compatibility
The Tubing Head Spool and Tubing Hanger form one critical mechanical and sealing interface.
| Tubing Hanger Type | Typical Use | Main Tubing Head Interface |
|---|---|---|
| Mandrel Tubing Hanger | Conventional production / injection | Bowl, shoulder and seal diameter |
| Slip-Type Tubing Hanger | Selected completion / workover | Slip and landing profile |
| Extended-Neck Tubing Hanger | Production wellhead | Neck OD and adapter seals |
| ESP Tubing Hanger | ESP artificial lift | Electrical penetrator |
| SCSSV Control-Line Hanger | Safety-valve completion | Hydraulic passages |
| Single-String Hanger | Conventional production | Single tubing bore |
| Dual-String Hanger | Dual-zone completion | Dual-bore spacing |
| Replacement Tubing Hanger | Mature-field wellhead | Existing bowl and seal geometry |
Tubing OD alone does not define the required Tubing Head interface.
The hanger landing profile, sealing diameter, suspended tubing load, completion feed-throughs and upper equipment also influence compatibility.
Tubing Head Spool Side Outlets and Annulus Control
A Tubing Head Spool with side outlets provides controlled access to the tubing-casing annulus.
| Annulus Function | Typical Use | Information to Confirm |
|---|---|---|
| Annulus Pressure Monitoring | Production monitoring | Gauge and outlet connection |
| Pressure Testing | Wellhead / annulus integrity verification | Test pressure |
| Controlled Bleed-Off | Annulus pressure management | Valve arrangement |
| Completion Circulation | Completion or workover | Flow requirement |
| Chemical Service | Selected treatment operations | Fluid compatibility |
| Instrumentation | Local or remote monitoring | Instrument connection |
| Replacement Matching | Retain existing piping position | Outlet orientation |
For new wellhead equipment, side-outlet orientation should be confirmed before final drawing approval.
For a Replacement Tubing Head Spool, outlet position becomes especially important because existing annulus valves, gauges and field piping may remain in service.
Materials, Temperature and Sour-Service Selection
The Tubing Head Spool forms part of the pressure-containing wellhead system, so material selection should reflect actual operating conditions.
| Service Condition | Main Design Focus | Useful RFQ Information |
|---|---|---|
| Oil Production | Pressure, tubing load and annulus monitoring | Pressure, tubing and tree |
| Natural Gas | Pressure integrity and sealing | Gas pressure and composition |
| H2S / Sour Gas | Material and hardness control | H2S and material requirement |
| CO2 Service | Corrosion review | CO2 and fluid composition |
| Produced Water | Corrosion and seal compatibility | Water chemistry |
| Water Injection | Injection pressure and corrosion | Pressure and water composition |
| Gas Injection | High-pressure containment | Gas pressure and composition |
| Offshore Wellhead | Corrosion, documentation and completion interfaces | Environment and specification |
| ESP Production | Electrical feed-through | Hanger, cable and penetrator |
| SCSSV Completion | Hydraulic feed-through | Control-line data |
Selected SGPE wellhead configurations can cover approximately -46°C to +121°C where the approved design supports that range.
Final operating limits depend on the actual body material, sealing system and approved project datasheet.
Tubing Head Spool vs Casing Spool vs Tubing Head Adapter
These API 6A wellhead components work together but perform different functions.
| Equipment | Primary Function | Main Interface | Typical Position |
|---|---|---|---|
| Casing Head | Starts the surface wellhead and supports casing | Surface casing | Lower wellhead |
| Casing Spool | Adds casing suspension and casing-annulus stage | Casing Hanger | Middle wellhead |
| Tubing Head Spool | Supports Tubing Hanger and controls tubing-casing annulus | Production / injection tubing | Upper wellhead |
| Tubing Hanger | Suspends and seals tubing | Inside Tubing Head | Inside spool |
| Tubing Head Adapter | Connects tubing-head area to tree | Tubing Head / Hanger to tree | Above Tubing Head |
| Christmas Tree | Controls production or injection flow | Valves and flowline | Top of wellhead |
A Casing Spool cannot replace a Tubing Head Spool simply because the external flange dimensions appear similar.
Likewise, a Tubing Head Adapter does not perform the same function as the Tubing Head Spool. This distinction becomes especially important when sourcing replacement components for an existing wellhead.
Replacement API 6A Tubing Head Spool
A Replacement API 6A Tubing Head Spool often requires more interface control than equipment for a new wellhead.
A mature field may retain its Casing Head, Casing Spool, tubing hanger, annulus valves, field piping or Christmas Tree. The replacement spool therefore needs to match both the required pressure rating and the installed geometry.
SGPE supports Replacement Tubing Head Spools, Custom Tubing Spools, obsolete Wellhead Tubing Heads, retrofit Tubing Heads and oilfield MRO replacement equipment.
| Existing Equipment Information | Why It Matters |
|---|---|
| Nameplate | Identifies equipment and pressure rating |
| Original Drawing | Provides dimensions and interfaces |
| Top Connection | Matches adapter / tree |
| Bottom Connection | Matches Casing Spool |
| RTJ Information | Confirms pressure-sealing interface |
| Internal Bore | Checks drift and hanger compatibility |
| Tubing-Hanger Drawing | Confirms bowl and sealing profile |
| Existing Hanger Dimensions | Supports replacement matching |
| Overall Height | Maintains stack elevation |
| Side-Outlet Size | Matches annulus valves |
| Outlet Orientation | Matches installed piping |
| Lockdown Arrangement | Confirms hanger retention |
| Adapter / Tree Drawing | Confirms upper interface |
| Existing Part Number | Supports cross-reference |
| Well Pressure | Confirms required pressure class |
| Well Fluid | Supports material review |
| Field Photographs | Shows the installed arrangement |
Matching the external flange alone does not guarantee a successful replacement.
A new spool may connect to the existing wellhead yet fail to accept the original tubing hanger. The internal bowl, landing shoulder, sealing diameter, minimum bore, overall height and side-outlet arrangement also need to match.
Existing drawings and verified field dimensions therefore become especially valuable when sourcing a replacement wellhead Tubing Spool, obsolete Tubing Head replacement or mature-field MRO component.
Custom API 6A Tubing Head Spool
A Custom API 6A Tubing Head Spool can solve interface problems when a catalogue configuration does not match an existing wellhead or special completion.
Customization can involve different upper and lower connections, flanged or studded interfaces, project-specific tubing-hanger profiles, internal bore, overall height, side-outlet arrangement, ESP feed-throughs, SCSSV control lines or replacement dimensions.
The proposed configuration should be developed around the mating equipment and actual project requirements rather than around a generic nominal size.
This capability is useful for buyers searching for a custom Tubing Head Spool manufacturer, replacement wellhead supplier, oilfield MRO supplier or API 6A wellhead equipment supplier for non-standard projects.
API 6A Tubing Head Spool Inspection, Testing and Documentation
Oil companies, EPC contractors, drilling contractors and wellhead distributors often require more than the finished component.
Depending on the agreed supply scope, project documentation can include the following items.
| Inspection / Document | Typical Purpose |
|---|---|
| Approved Manufacturing Drawing | Confirms final dimensions and interfaces |
| Material Traceability | Tracks pressure-containing material |
| Material Certificate | Records material information |
| Dimensional Inspection | Confirms bore, flange and outlet dimensions |
| API Connection Inspection | Confirms connection geometry |
| RTJ Groove Inspection | Confirms sealing interface |
| NDE | Supports quality control |
| Hardness Verification | Supports specified service requirements |
| Hydrostatic Pressure Test | Confirms pressure integrity under approved procedure |
| Assembly / Interface Check | Confirms matched components where applicable |
| Coating Inspection | Confirms specified surface protection |
| Final Inspection | Confirms release condition |
| Pressure-Test Report | Records test results |
| NDE Reports | Records inspection results |
| Packing Documentation | Supports project or export delivery |
| Third-Party Inspection | Supports customer witness or hold points |
Special ITP requirements, third-party inspection requirements and witness points should be identified during the RFQ stage whenever possible.
EPC, MRO and Wellhead Replacement Procurement
Different buyers begin an API 6A Tubing Head Spool purchase with different levels of technical information.
An EPC contractor may already have a complete datasheet, project specification and ITP. A drilling or completion contractor may have only a wellhead stack drawing. A mature-field operator may begin with a nameplate, field photographs and several verified dimensions.
The available information can be used to identify what still needs clarification before quotation.
This approach is particularly useful for EPC procurement, oilfield MRO, wellhead retrofit and replacement projects, where a buyer may not have a complete original engineering package.
For new projects, the Tubing Head Spool can also be coordinated with the Casing Spool, Tubing Hanger, Tubing Head Adapter and Christmas Tree to reduce interface risk.
API 6A Tubing Head Spool Installation and Maintenance
Before installation, the field team should compare the Tubing Head Spool with the approved drawing and actual mating equipment.
The check should cover the upper and lower connections, RTJ grooves, internal bore, tubing-hanger profile, side outlets and overall height. Ring grooves, sealing surfaces and hanger landing areas should remain clean and protected before assembly.
Replacement equipment also requires verification of side-outlet orientation and clearance around annulus valves, gauges and existing piping. ESP and SCSSV completions add checks for electrical penetrators or hydraulic control lines.
During service, operators should monitor external corrosion, flange areas, side-outlet connections, annulus valves, visible leakage and mechanical damage.
Workover or recompletion provides an opportunity to inspect accessible RTJ grooves, hanger landing surfaces and sealing areas.
The original Tubing Head Spool drawing, connection data, tubing-hanger information and seal records should be retained because these documents simplify future maintenance, troubleshooting, MRO and replacement.
API 6A Tubing Head Spool Price and Quotation Factors
Buyers frequently search for API 6A Tubing Head Spool price, Tubing Spool price, Wellhead Tubing Head price, 10K Tubing Head price, 15K Tubing Head quotation or API 6A wellhead equipment price.
One fixed price cannot represent every configuration.
A conventional 3K Production Tubing Head requires different material, forging, machining and inspection from a 15K sour-service Tubing Spool for a high-pressure gas well.
| Price Factor | Effect on Quotation |
|---|---|
| Working Pressure | Affects body, connections and testing |
| Nominal Connection Size | Influences forging size |
| Top / Bottom Connection | Influences machining |
| API 6B / 6BX Interface | Affects connection geometry |
| Internal Bore | Changes body geometry |
| Tubing-Hanger Profile | Requires matched internal machining |
| Overall Height | Influences material and machining |
| Body Material | Influences raw-material cost |
| Material Class | Influences manufacturing scope |
| Sour Service | Can add material and hardness controls |
| Side Outlets | Add machining and connection requirements |
| ESP Completion | Adds penetrator-interface requirements |
| SCSSV Lines | Add completion-interface requirements |
| Dual Completion | Adds bore and orientation complexity |
| Custom Design | Adds engineering |
| Replacement Matching | Can require dimensional reconstruction |
| PSL / Inspection Scope | Influences manufacturing controls |
| Third-Party Inspection | Adds inspection coordination |
| Documentation | Changes final dossier scope |
| Quantity | Influences production planning |
For an accurate API 6A Tubing Head Spool price and quotation, buyers should provide the actual wellhead interfaces rather than requesting only a generic price based on nominal size.
Complete API 6A Wellhead Equipment Supply from SGPE
The Tubing Head Spool normally forms one part of a complete API 6A surface wellhead.
SGPE can coordinate it with related equipment, including API 6A Casing Heads, Casing Spools, Casing Hangers, Tubing Hangers, Tubing Head Adapters, Spacer Spools, API 6A Gate Valves and Wellhead Christmas Trees.
For new projects, matched components can simplify flange compatibility, bore alignment, pressure-class coordination and technical documentation.
For replacement projects, buyers can also source only the required Tubing Head Spool while keeping the remaining wellhead equipment in service.
This flexibility supports oil companies, EPC contractors, drilling contractors, oilfield service companies, wellhead distributors and MRO buyers that need either one replacement component or a coordinated wellhead package.
Why Choose SGPE as an API 6A Tubing Head Spool Manufacturer & Supplier?
Buyers comparing an API 6A Tubing Head Spool manufacturer, Tubing Spool supplier, Production Tubing Head manufacturer, replacement wellhead supplier or custom API 6A wellhead equipment supplier need more than a generic forged body.
A useful technical proposal must consider the pressure, mechanical and installation interfaces around the complete wellhead.
SGPE evaluates the Tubing Head Spool together with the casing wellhead, tubing hanger, completion system and upper Christmas Tree. This approach supports conventional production wellheads, 2K to 15K pressure classes, high-pressure gas wells, ESP artificial-lift completions, offshore SCSSV applications, water and gas injection, dual-string completions, sour-service wells, workover programs, Christmas Tree upgrades and mature-field replacement.
Project-specific requirements can include different upper and lower connections, tubing-hanger profiles, side-outlet orientations, ESP or SCSSV interfaces and replacement dimensions.
Depending on the agreed scope, the supply can include manufacturing drawings, material records, inspection reports, NDE documentation and pressure-test records.
For buyers comparing API 6A Tubing Head Spool suppliers and quotations, a proposal based on the actual wellhead interfaces provides more useful information than a generic quotation based only on nominal size.
API 6A Tubing Head Spool RFQ Data Sheet
The following information helps SGPE prepare an accurate Tubing Head Spool price, technical proposal and commercial quotation.
| RFQ Item | Information to Provide |
|---|---|
| Product | API 6A Tubing Head Spool / Tubing Spool |
| Quantity | Required quantity |
| Application | Oil, gas, ESP, offshore, injection, workover or replacement |
| Working Pressure | 2K / 3K / 5K / 10K / 15K |
| Top Connection | Complete designation |
| Bottom Connection | Complete designation |
| RTJ Information | Top and bottom details |
| Production Casing | Size and lower wellhead information |
| Production / Injection Tubing | Tubing OD and completion details |
| Tubing Hanger | Type, drawing or dimensions |
| Internal Bore | Required bore / drift |
| Suspended Tubing Load | Design value where available |
| Side Outlets | Quantity, size, connection and pressure |
| Outlet Orientation | Required angle |
| Tubing Head Adapter | Drawing / connection |
| Christmas Tree | Lower tree interface |
| ESP Completion | Cable and penetrator information |
| SCSSV | Control-line quantity, size and pressure |
| Other Feed-Throughs | Chemical injection / monitoring |
| Well Fluid | Oil, gas, produced water or injection fluid |
| H2S / CO2 | Sour-service information |
| Temperature | Minimum and maximum |
| Material Class | Project requirement |
| PSL | Project requirement |
| Surface Protection | Project requirement |
| Inspection | Customer / TPI requirement |
| Documentation | Required reports and certificates |
| Existing Drawing | Replacement projects |
| Nameplate | Clear photograph |
| Field Photographs | Spool and mating equipment |
| Overall Height | Replacement dimension |
| Existing Part Number | If available |
| Destination | Country / project location |
If complete technical information is not yet available, buyers can begin with an existing wellhead drawing, nameplate and clear field photographs.
These references usually provide enough information to identify the remaining items needed for technical clarification.
Frequently Asked Questions About API 6A Tubing Head Spools
1. What is an API 6A Tubing Head Spool?
An API 6A Tubing Head Spool forms part of a surface oil and gas wellhead. It provides the landing and sealing interface for the tubing hanger and connects the casing-support section to the upper completion or Christmas Tree equipment.
Its side outlets also provide access to the tubing-casing annulus for pressure monitoring, testing, controlled bleed-off, circulation and other approved operations.
The equipment may also be called a Tubing Spool, Production Tubing Head, Wellhead Tubing Head, Production Tubing Head Spool or Oilfield Tubing Head.
2. What is the difference between a Tubing Head Spool and a Casing Spool?
A Casing Spool supports a Casing Hanger and forms part of the casing-support section of the wellhead. A Tubing Head Spool normally sits higher in the wellhead and supports the production or injection tubing hanger.
Although both components can use similar forged bodies, API connections and side outlets, their internal hanger profiles, sealing interfaces and operating functions differ.
A Casing Spool should therefore not replace a Tubing Head Spool simply because the flange size and working pressure appear similar.
3. What is the difference between a Tubing Head Spool and a Tubing Head Adapter?
The Tubing Head Spool provides the tubing-hanger landing profile and tubing-casing annulus access.
The Tubing Head Adapter normally sits above the tubing-head area and connects toward the Christmas Tree.
In an extended-neck hanger system, the tubing hanger may also seal into the adapter. The spool, hanger and adapter therefore need compatible dimensions and sealing interfaces.
4. What pressure ratings are available for API 6A Tubing Head Spools?
Project configurations can cover 2,000 psi, 3,000 psi, 5,000 psi, 10,000 psi and 15,000 psi, subject to final technical confirmation.
A 2K, 3K or 5K Tubing Head can suit many conventional production, injection and replacement projects.
A 10K or 15K High Pressure Tubing Head Spool requires closer review of the pressure-containing body, connections, RTJ interfaces, tubing hanger, materials, sealing system and mating equipment.
5. What API 6A Tubing Head Spool sizes and connections are available?
The required Tubing Head size depends on the casing wellhead, tubing hanger, upper equipment and pressure rating.
Common RFQs may involve 7-1/16″, 9″, 11″ and 13-5/8″ wellhead interfaces, subject to the actual system design. API 6B or API 6BX connections may apply where appropriate.
An RFQ for an 11 Inch 10K Tubing Head Spool should also include the upper and lower connection details, RTJ information, internal bore, hanger profile and side outlets.
6. What tubing sizes and tubing hangers can a Tubing Head Spool support?
Common completion programs can involve 2-3/8″, 2-7/8″, 3-1/2″ and 4-1/2″ production or injection tubing, subject to technical confirmation.
Tubing-hanger configurations can include mandrel, slip-type, extended-neck, ESP, control-line, single-string and dual-string designs.
Tubing OD alone does not define the spool. Hanger profile, sealing geometry, suspended load and completion feed-throughs also influence the final configuration.
7. Can SGPE supply 10K and 15K High Pressure Tubing Head Spools?
Yes. SGPE can review 10,000 psi and 15,000 psi API 6A Tubing Head Spool requirements within the approved project scope.
A high-pressure RFQ should include the upper and lower connections, minimum bore, tubing-hanger configuration, operating temperature, material requirements, side outlets, PSL and mating wellhead equipment.
These details become particularly important for high-pressure gas, injection and sour-service applications.
8. Can an API 6A Tubing Head Spool support an ESP completion?
Yes. An ESP Tubing Head Spool can work with a matched ESP tubing hanger and electrical penetrator or cable feed-through.
The technical review should cover tubing size, hanger design, penetrator, cable arrangement, working pressure, operating temperature and upper adapter.
During an ESP retrofit, the existing casing wellhead may remain in service while the Tubing Head Spool, hanger or upper adapter changes.
9. Can a Tubing Head Spool accommodate SCSSV control lines?
Yes. Selected tubing hangers can incorporate hydraulic passages for a Surface-Controlled Subsurface Safety Valve.
The RFQ should identify the number of control lines, line size, hydraulic pressure and required orientation.
Some completion systems may also include chemical-injection or monitoring feed-throughs, so these interfaces should be considered together during wellhead selection.
10. Can SGPE supply an H2S or Sour Service Tubing Head Spool?
SGPE can review Sour Service API 6A Tubing Head Spool requirements for wells containing H2S, CO2, produced water or other specified corrosive constituents.
Buyers should provide the actual service conditions, operating temperature and material requirements because these factors influence material selection, hardness, sealing arrangements, inspection and documentation.
Pressure rating alone does not determine sour-service suitability.
11. Can SGPE manufacture a Replacement API 6A Tubing Head Spool?
Yes. SGPE supports Replacement Tubing Head Spools, Custom Tubing Spools and obsolete wellhead replacement projects for mature oil and gas fields.
Useful references include the existing drawing, nameplate, upper and lower connections, RTJ details, internal bore, tubing-hanger drawing, overall height, side-outlet arrangement and field photographs.
The external flange is only one part of replacement compatibility. Internal bowl geometry, seal diameter, hanger landing position and stack height also need to match.
12. What information should I send for an API 6A Tubing Head Spool price and quotation?
For an accurate API 6A Tubing Head Spool quotation, send the working pressure, upper and lower connections, casing information, tubing size, tubing-hanger design, internal bore, side outlets, operating temperature, well fluid and material requirements.
For an ESP completion, include cable and penetrator information. For SCSSV service, provide hydraulic control-line data. For sour service, include H2S / CO2 and applicable material requirements.
For a replacement project, send the existing drawing, nameplate, RTJ information, field photographs and available dimensions.
The final Tubing Head Spool price depends on pressure class, connection combination, forging size, internal hanger profile, material, sour-service requirements, side outlets, completion interfaces, inspection scope and documentation.
Request an SGPE API 6A Tubing Head Spool Quotation
Applications include onshore and offshore oil and gas production, 10K and 15K high-pressure wells, ESP artificial lift, SCSSV completions, water and gas injection, dual-string completions, workover, recompletion and Christmas Tree upgrades.
For a new API 6A Tubing Head Spool RFQ, please provide the working pressure, casing and tubing program, tubing-hanger requirement, upper and lower connections and project specification.
For replacement projects, send the existing drawing or nameplate, flange and RTJ details, tubing-hanger information, overall height, side-outlet arrangement and clear photographs.
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