Description
API 16A Annular BOP Blowout Preventer for Drilling Wellhead Control
SGPE supplies Annular BOP Blowout Preventers for oil and gas drilling well control, drilling rig BOP stacks, workover pressure control packages, well testing operations, well intervention systems, flowback service, and high-pressure oilfield pressure control applications.
The annular BOP normally installs at the top of the BOP stack and forms a flexible seal around drill pipe, tubing, casing, kelly, tool joints, and selected irregular pipe profiles. In addition, under suitable operating conditions, it can close the open hole and support controlled stripping operations.
This type of blowout preventer gives drilling crews a fast and flexible sealing barrier during kick control, well shut-in, tripping, pressure testing, workover, well testing, flowback, and emergency well control operations. Because it can seal around different tubular sizes, it plays an important role in both land rig and offshore rig well control systems.
Oilfield buyers may also describe this equipment as an Annular Blowout Preventer, Annular BOP Preventer, API 16A Annular BOP, API 16A Annular Blowout Preventer, Hydraulic Annular BOP, BOP Stack Annular Preventer, Oilfield Annular BOP, Drilling Annular BOP, Well Control Annular BOP, Spherical Annular BOP, Taper Annular BOP, Tapered Rubber Annular BOP, 5K Annular BOP, 10K Annular BOP, 13-5/8 Annular BOP, or 18-3/4 Annular BOP.
Internal parts exposed to drilling fluid or well fluid can meet NACE MR0175 requirements for sour service and H2S oilfield environments when the project specifies sour service. In addition, temperature class can follow T-20/250 or project-specific contract requirements.
Product Summary
SGPE Annular BOP Blowout Preventer is an API 16A well control device for drilling BOP stacks, workover units, well testing packages, well intervention systems, and high-pressure oilfield pressure control service. It is available in spherical rubber and taper rubber structures, with common bore sizes from 7-1/16″ to 21-1/4″ and pressure ratings from 2,000 psi to 10,000 psi.
The equipment can seal around drill pipe, tubing, casing, kelly, tool joints, and irregular pipe profiles. Also, it can close the open hole when the operating condition, rubber element status, pressure rating, and well control procedure allow it. Therefore, buyers should match the annular BOP model with the actual well control program before confirming an order.
Quick Product Overview
| Item | Description |
|---|---|
| Product Name | Annular BOP Blowout Preventer |
| Alternative Names | Annular Blowout Preventer, Annular BOP Preventer, API 16A Annular BOP, BOP Stack Annular Preventer |
| Standard | API Spec 16A |
| Main Types | Spherical Annular BOP and Taper Annular BOP |
| Common Bore Sizes | 7-1/16″, 9″, 11″, 13-5/8″, 16-3/4″, 18-3/4″, 20-3/4″, 21-1/4″ |
| Common Pressure Ratings | 2,000 psi, 3,000 psi, 5,000 psi, 10,000 psi |
| Hydraulic Rated Working Pressure | 13.8 MPa / 2,000 psi |
| Recommended Hydraulic Pressure for Pipe Sealing | ≤10.5 MPa / ≤1,524 psi |
| Rubber Type | Spherical rubber packing element or tapered rubber packing element |
| Typical Stack Position | Top section of drilling BOP stack |
| Main Applications | Drilling well control, workover, well testing, well intervention, flowback, pressure control package |
| Sour Service | Available according to NACE MR0175 project requirements |
| Matching Equipment | Ram BOP, BOP control unit, accumulator unit, choke manifold, kill manifold, drilling spool, BOP test unit |
Product Overview
An annular blowout preventer uses hydraulic pressure to move the piston and compress the rubber packing element. During closing, the packing element moves inward and seals around the pipe string or closes the wellbore. During opening, hydraulic oil enters the opening chamber, the piston returns, and the rubber element releases the bore.
As a result, the annular BOP provides reliable sealing performance, quick response, and wide pipe-size coverage in well control operations. It can work with ram BOPs, drilling spools, adapter spools, spacer spools, choke manifolds, kill manifolds, BOP control units, accumulator units, high-pressure test units, and BOP test stumps.
SGPE offers two common annular BOP structure types:
Model A: Tapered Rubber Annular BOP
Model B: Spherical Rubber Annular BOP
Both types seal the annular space around the pipe or close the wellbore. However, each structure has different rubber geometry, support design, sealing behavior, maintenance requirements, and suitable oilfield applications. Therefore, buyers should confirm bore size, working pressure, stack design, hydraulic control capacity, drilling program, spare rubber requirement, and sour service condition before ordering.
Main Annular BOP Types
Spherical Annular BOP
A Spherical Annular BOP uses a spherical rubber packing element. This structure gives the rubber core smooth compression movement and helps the element close evenly around drill pipe, tubing, casing, and other oilfield tubulars. For this reason, many drilling contractors choose this type for standard drilling well control, land rig BOP stacks, offshore rig BOP stacks, workover units, and well testing pressure control packages.
The main structure of a spherical annular BOP usually includes an upper housing, body, piston, spherical rubber packing element, and anti-dust ring. These components work together to guide rubber movement, support hydraulic closing force, protect the internal sealing area, and maintain stable operation during well control service.
The spherical rubber element provides flexible sealing around different pipe sizes. In addition, it supports well shut-in and controlled stripping operations when the drilling procedure allows pipe movement under pressure. In many BOP stack layouts, the spherical annular BOP works above ram BOPs and provides the first flexible sealing barrier for the drilling crew.
Common spherical models cover bore sizes such as 7-1/16″, 9″, 11″, 13-5/8″, 18-3/4″, 20-3/4″, and 21-1/4″. Meanwhile, common pressure ratings include 2,000 psi, 3,000 psi, and 5,000 psi, depending on model and bore size.
Taper Annular BOP
A Taper Annular BOP uses a tapered rubber packing element. This structure gives the rubber stronger support during closing and helps the BOP handle higher well control pressure in demanding drilling conditions. Therefore, buyers often choose tapered rubber annular BOPs for 10,000 psi drilling projects, high-pressure wells, deep well drilling programs, heavy-duty land rigs, offshore drilling packages, and high-spec BOP stacks.
The main structure of a taper annular BOP usually includes an upper housing, wear plate, body, piston, tapered rubber packing element, anti-dust ring, and supporting cylinder. During operation, these parts help guide piston movement, support rubber deformation, reduce wear in key contact areas, and improve sealing stability under high-pressure well control conditions.
The wear plate and supporting cylinder improve structural support during closing. As a result, the taper annular BOP can maintain stable sealing performance in high-pressure oilfield well control conditions. Common model options cover bore sizes such as 7-1/16″, 11″, 13-5/8″, 16-3/4″, 18-3/4″, and 21-1/4″. In addition, pressure ratings include 2,000 psi, 3,000 psi, 5,000 psi, and 10,000 psi.
Structure Options and Connection Forms
The upper housing and body can use a bolted connection or a claw chuck connection. The bolted design gives oilfield BOP equipment stable mechanical strength and convenient maintenance access. By contrast, the claw chuck design supports faster assembly and disassembly in certain BOP configurations.
The final structure should match the BOP model, rig maintenance preference, pressure rating, stack design, and project technical requirements. In addition, the annular BOP can connect with other well control equipment through flanged connections, studded connections, or project-specified interface designs.
| Structure / Connection Item | Common Option | Buyer Check Point |
| Body and Upper Housing Connection | Bolted connection / claw chuck connection | Match rig maintenance preference and BOP model |
| Top and Bottom Connection | Flanged, studded, or project-specific interface | Confirm flange size, pressure rating, ring groove, and stack layout |
| Rubber Structure | Spherical rubber / tapered rubber | Match well pressure, pipe range, and spare part plan |
| Hydraulic Operation | Closing chamber and opening chamber | Check BOP control unit capacity and accumulator volume |
| Sour Service Option | NACE MR0175 as required | Confirm H2S, CO2, temperature, and material requirements |
Key Features
| Feature | Practical Value |
| Wide sealing range | Seals around drill pipe, tubing, casing, kelly, tool joints, and selected irregular pipe profiles |
| Open-hole closing capability | Can close the open hole under suitable operating conditions and approved well control procedures |
| Fast hydraulic operation | Works with the BOP control unit and accumulator unit for quick closing and opening |
| Spherical and tapered rubber options | Helps buyers match the BOP design with well pressure, pipe range, and maintenance plan |
| Common oilfield bore sizes | Covers many land rig, offshore rig, workover, and well testing BOP stack requirements |
| API 16A manufacturing support | Supports API 16A project requirements, inspection records, and technical documentation |
| Sour service availability | Internal well-fluid-contact parts can meet NACE MR0175 requirements when specified |
Spherical Annular BOP Model Range
The following spherical annular BOP models help drilling contractors and rig package buyers compare bore size, working pressure, hydraulic control pressure, and approximate lifting weight before technical confirmation. However, final data should follow the signed technical agreement.
| Model | Bore Size | Rated Working Pressure | Hydraulic Rated Working Pressure | Approx. Weight |
| FH18-21 | 179.4 mm / 7-1/16″ | 20.7 MPa / 3,000 psi | 13.8 MPa / 2,000 psi | 1,433 kg |
| FH18-35 | 179.4 mm / 7-1/16″ | 34.5 MPa / 5,000 psi | 13.8 MPa / 2,000 psi | 1,520 kg |
| FH23-21 | 228.6 mm / 9″ | 20.7 MPa / 3,000 psi | 13.8 MPa / 2,000 psi | 2,440 kg |
| FH23-35 | 228.6 mm / 9″ | 34.5 MPa / 5,000 psi | 13.8 MPa / 2,000 psi | 3,050 kg |
| FH28-14 | 279.4 mm / 11″ | 13.8 MPa / 2,000 psi | 13.8 MPa / 2,000 psi | 3,512 kg |
| FH28-21 | 279.4 mm / 11″ | 20.7 MPa / 3,000 psi | 13.8 MPa / 2,000 psi | 3,400 kg |
| FH28-35 | 279.4 mm / 11″ | 34.5 MPa / 5,000 psi | 13.8 MPa / 2,000 psi | 4,716 kg |
| FH35-21 | 346.1 mm / 13-5/8″ | 20.7 MPa / 3,000 psi | 13.8 MPa / 2,000 psi | 5,700 kg |
| FH35-35 | 346.1 mm / 13-5/8″ | 34.5 MPa / 5,000 psi | 13.8 MPa / 2,000 psi | 6,415 kg |
| FH48-35 | 476.3 mm / 18-3/4″ | 34.5 MPa / 5,000 psi | 13.8 MPa / 2,000 psi | 16,320 kg |
| FH53-21 | 527 mm / 20-3/4″ | 20.7 MPa / 3,000 psi | 13.8 MPa / 2,000 psi | 6,994 kg |
| FH54-35 | 539.7 mm / 21-1/4″ | 34.5 MPa / 5,000 psi | 13.8 MPa / 2,000 psi | 20,220 kg |
Taper Annular BOP Model Range
The following taper annular BOP models suit high-pressure and heavy-duty drilling well control applications. Therefore, buyers often select them for deep wells, high-pressure formations, high-spec rig packages, and 10,000 psi BOP stack requirements.
| Model | Bore Size | Rated Working Pressure | Hydraulic Rated Working Pressure | Close Volume | Open Volume | Approx. Weight |
| FHZ18-70 | 179.4 mm / 7-1/16″ | 69 MPa / 10,000 psi | 13.8 MPa / 2,000 psi | 36 L | 27 L | 6,239 kg |
| FHZ28-70 | 279.4 mm / 11″ | 69 MPa / 10,000 psi | 13.8 MPa / 2,000 psi | 67 L | 66 L | 12,290 kg |
| FHZ28-105 | 279.4 mm / 11″ | 69 MPa / 10,000 psi | 13.8 MPa / 2,000 psi | 121 L | 120 L | 17,640 kg |
| FHZ35-35 | 346.1 mm / 13-5/8″ | 34.5 MPa / 5,000 psi | 13.8 MPa / 2,000 psi | 68 L | 54 L | 6,917 kg |
| FHZ35-70 | 346.1 mm / 13-5/8″ | 69 MPa / 10,000 psi | 13.8 MPa / 2,000 psi | 116 L | 117 L | 15,190 kg |
| FHZ43-21 | 425.5 mm / 16-3/4″ | 20.7 MPa / 3,000 psi | 13.8 MPa / 2,000 psi | 118 L | 84 L | 7,098 kg |
| FHZ43-35 | 425.5 mm / 16-3/4″ | 34.5 MPa / 5,000 psi | 13.8 MPa / 2,000 psi | 112 L | 78 L | 10,030 kg |
| FHZ48-70 | 476.3 mm / 18-3/4″ | 69 MPa / 10,000 psi | 13.8 MPa / 2,000 psi | 220 L | 220 L | 27,016 kg |
| FHZ54-14 | 539.7 mm / 21-1/4″ | 13.8 MPa / 2,000 psi | 13.8 MPa / 2,000 psi | 136.5 L | 84.9 L | 7,660 kg |
Main Technical Parameters
| Item | Specification Range |
| Product Name | Annular BOP Blowout Preventer |
| Product Type | Spherical Annular BOP / Taper Annular BOP |
| Standard | API Spec 16A |
| Common Bore Sizes | 7-1/16″, 9″, 11″, 13-5/8″, 16-3/4″, 18-3/4″, 20-3/4″, 21-1/4″ |
| Working Pressure | 2,000 psi, 3,000 psi, 5,000 psi, 10,000 psi |
| Hydraulic Rated Working Pressure | 13.8 MPa / 2,000 psi |
| Recommended Hydraulic Pressure for Pipe Sealing | ≤10.5 MPa / ≤1,524 psi |
| Rubber Type | Spherical rubber or tapered rubber |
| Connection Form | Bolted connection or claw chuck connection |
| Sour Service | Available according to NACE MR0175 project requirements |
| Temperature Class | T-20/250 or as required by contract |
| Oilfield Applications | Drilling well control, BOP stack, land rig, offshore rig, workover, well testing, well intervention, pressure control package |
How an Annular BOP Blowout Preventer Works
The Annular BOP Blowout Preventer uses hydraulic force and rubber deformation to seal the wellbore. During closing, the BOP control system sends hydraulic oil into the closing chamber. Then the piston moves upward and squeezes the rubber packing element. As a result, the rubber moves inward and forms a seal around drill pipe, tubing, casing, or other oilfield tubulars.
During opening, the control system sends hydraulic oil into the opening chamber. After that, the piston moves back, the packing element releases the bore, and the wellbore opens again.
Each part must perform accurately in real drilling conditions. For example, the piston surface, body chamber, rubber element, wear plate, upper housing, anti-dust ring, seal area, and hydraulic ports all affect closing performance. Therefore, machining accuracy, assembly control, pressure testing, and inspection records matter for every annular blowout preventer.
Oilfield Applications
SGPE Annular BOP Blowout Preventers suit oilfield drilling, workover, well testing, well intervention, flowback, sour service, and high-pressure pressure control operations.
Main Oilfield Applications
| Application | How the Annular BOP Helps |
| Drilling BOP Stack | Provides the first flexible sealing barrier above ram BOPs |
| Land Drilling Rig | Supports well control during drilling, tripping, pressure testing, and kick control |
| Offshore Drilling Rig | Helps manage well control risk where space, access, and safety requirements are strict |
| Workover Unit | Seals around tubing, work strings, and service tools |
| Well Testing Package | Helps shut in the well and control pressure during test operations |
| Flowback Operation | Supports temporary pressure control during flowback and cleanup |
| Sour Service Well | Works with suitable material and NACE MR0175 requirements when H2S exists |
| High-Pressure Well | Uses proper pressure rating, rubber type, and hydraulic control capacity |
Application Selection Notes
For drilling BOP stacks, the annular BOP usually sits above single ram BOPs, double ram BOPs, drilling spools, adapter spools, choke manifolds, kill manifolds, and BOP control units. Therefore, it can provide the first flexible sealing barrier during drilling, tripping, and well shut-in operations.
Land drilling rigs, offshore drilling rigs, workover units, and well testing packages may all require annular BOPs. However, the selection logic is not always the same. Land rigs usually focus on rig size, casing program, bore size, and working pressure.
Offshore projects often require stronger documentation control, inspection records, packing element planning, and clear interface confirmation. Meanwhile, workover and well testing packages may require compact pressure control layouts and flexible sealing around tubing, work strings, or service tools.
Spherical Rubber vs Tapered Rubber
Both spherical and tapered annular BOPs can provide reliable sealing performance in oilfield well control systems. However, buyers should select the structure according to drilling conditions, pressure rating, spare parts plan, and existing BOP stack design.
| Type | Best Fit | Main Advantage | Common Search Terms |
| Spherical Annular BOP | Standard drilling, workover, well testing, land rig and offshore rig BOP stacks | Smooth rubber compression and wide model availability | Spherical Annular BOP, Spherical Rubber Annular BOP |
| Taper Annular BOP | High-pressure wells, deep wells, 10K BOP stacks, heavy-duty drilling service | Strong rubber support and stable sealing under demanding conditions | Taper Annular BOP, Tapered Rubber Annular BOP, 10K Annular BOP |
For replacement projects, buyers should check the current BOP model, bore size, pressure rating, connection dimensions, rubber spare part code, hydraulic volume, and BOP stack layout before ordering. This step helps avoid installation mismatch, spare part confusion, and rig site delay.
Selection Guide for Annular BOP Blowout Preventer
Choosing the correct Annular BOP Blowout Preventer requires more than matching the bore size. A proper selection reduces field installation problems, hydraulic control mismatch, spare part errors, pressure test issues, and rig downtime. Therefore, buyers should review both the BOP model and the operating condition before confirming an order.
| Selection Item | What to Confirm | Why It Matters |
| Bore Size | 7-1/16″, 9″, 11″, 13-5/8″, 16-3/4″, 18-3/4″, 20-3/4″, 21-1/4″ | Must match the drilling BOP stack and well program |
| Working Pressure | 2,000 psi, 3,000 psi, 5,000 psi, 10,000 psi | Must match stack rating and well control requirement |
| Rubber Structure | Spherical rubber or tapered rubber | Affects sealing behavior, maintenance, and spare part selection |
| Connection Type | Flanged, studded, bolted body, claw chuck structure | Prevents interface mismatch during installation |
| Hydraulic Volume | Close volume and open volume | Helps check BOP control unit and accumulator capacity |
| Service Condition | Standard, high-pressure, sour service, H2S, CO2 | Affects material, rubber, NACE, and temperature requirements |
| Documentation | MTC, hydrostatic test report, COC, NACE declaration | Supports project acceptance and third-party inspection |
After confirming the basic model, buyers should review the existing BOP stack drawing, top and bottom connection dimensions, ring gasket type, stud size, face-to-face dimension, hydraulic control volume, and required spare parts. For sour service projects, buyers should also confirm H2S, CO2, temperature, drilling fluid, and NACE MR0175 requirements.
If the annular BOP is used as a replacement unit, the rubber packing element type and spare part code should match the original design. Otherwise, field installation problems, spare part mismatch, or delayed commissioning may occur.
Quality Control and Testing
SGPE controls annular BOP quality through material inspection, machining control, assembly inspection, pressure testing, and final dimensional checking. Before shipment, the required documents can be prepared according to the purchase order and oilfield project requirements.
| Document / Inspection Item | Typical Purpose |
| Material Test Certificate | Confirms material grade and heat traceability |
| Hydrostatic Test Report | Confirms pressure test result before shipment |
| Dimensional Inspection Report | Confirms key interface and installation dimensions |
| Visual Inspection Report | Confirms appearance and visible surface condition |
| Assembly Inspection Record | Confirms assembly check and main component status |
| Certificate of Conformity | Confirms supply scope and order compliance |
| NACE MR0175 Declaration | Supports sour service and H2S project requirements |
| Operation and Maintenance Manual | Guides field operation, maintenance, and spare part planning |
| Spare Parts List | Helps buyers prepare packing elements, seals, and repair kits |
| Packing List and Shipping Mark | Supports logistics, customs, and site receiving work |
For third-party inspection, SGPE can coordinate with inspection companies according to the contract. For example, buyers may request inspection by SGS, BV, ABS, DNV, TUV, or other approved third-party agencies when the oilfield project needs external verification.
Spare Parts and Maintenance
| Maintenance Item | Check Purpose |
| Rubber Packing Element | Check wear, cuts, aging, swelling, and sealing condition |
| Hydraulic Chamber Seals | Prevent hydraulic leakage during opening and closing |
| Piston Surface | Ensure smooth movement and stable hydraulic response |
| Upper Housing and Body | Check connection areas and pressure-containing surfaces |
| Wear Plate and Supporting Parts | Maintain support for rubber movement and closing stability |
| Flange Ring Groove | Protect sealing interface with matching ring gasket |
| Studs and Nuts | Maintain safe stack connection and installation strength |
| Hydraulic Ports | Keep control line connection clean and functional |
Worn rubber elements and seals should be replaced according to actual oilfield working conditions. In particular, harsh drilling fluid, high temperature, sour service, frequent stripping, and repeated pressure cycles can shorten rubber service life. Therefore, a proper spare parts plan helps reduce rig downtime and improves well control readiness.
Compatible Equipment and Related Products
An annular BOP normally works as part of a complete drilling well control system. In many projects, buyers may also require related equipment for BOP stack assembly, rig package supply, pressure testing, or spare parts planning.
| Related Product | Typical Purpose |
| Ram BOP | Provides pipe ram, blind ram, or shear ram sealing in the BOP stack |
| Drilling Spool | Connects BOP equipment and provides outlets for choke and kill lines |
| Adapter Spool | Matches different flange sizes, pressure ratings, or stack interfaces |
| Spacer Spool | Adjusts stack height and interface spacing |
| BOP Control Unit | Supplies hydraulic pressure to operate annular BOPs and ram BOPs |
| Accumulator Unit | Stores hydraulic energy for emergency BOP operation |
| Choke Manifold | Controls well flow and pressure during well control operations |
| Kill Manifold | Supports kill fluid circulation during well control procedures |
| BOP Test Unit | Tests BOP stack pressure before or during drilling operations |
| BOP Test Stump | Supports pressure testing and stack preparation before installation |
| Packing Element and Seal Kit | Supports annular BOP maintenance and field replacement |
In addition, adding related products to the technical discussion helps buyers confirm interface dimensions, stack height, pressure rating, control volume, and field maintenance requirements before shipment.
Common RFQ Terms and Buyer Requirements
Different buyers may describe the same annular BOP in different ways. Therefore, the following tables help match common search terms, RFQ wording, and procurement intent.
General Annular BOP Search Terms
| Buyer Search Term | What Buyers Usually Need |
| Annular BOP Blowout Preventer | Flexible sealing BOP for oilfield drilling well control |
| API 16A Annular BOP Blowout Preventer | API standard annular BOP for drilling well control systems |
| Annular Blowout Preventer | BOP used to seal around pipe or close open hole during drilling operations |
| Annular BOP Preventer | Annular preventer for drilling rig well control systems |
| Annular Preventer | Short search term for annular blowout preventer |
| API 16A Annular BOP | Annular blowout preventer manufactured according to API Spec 16A |
| API 16A Annular Preventer | API 16A well control annular preventer for drilling BOP stacks |
| Well Control Annular BOP | Annular BOP used for well control and pressure control operations |
| Hydraulic Annular BOP | Hydraulically operated annular blowout preventer |
| Oilfield Annular BOP | Annular preventer for oil and gas drilling operations |
| Drilling Annular BOP | Annular BOP used for drilling rig well control systems |
| BOP Stack Annular Preventer | Annular BOP installed on top of an oilfield drilling BOP stack |
Annular BOP Type, Pressure, Size and Spare Parts Terms
| Buyer Search Term | What Buyers Usually Need |
| Spherical Annular BOP | Annular BOP with spherical rubber packing element |
| Spherical Rubber Annular BOP | Spherical rubber type annular BOP for flexible sealing |
| Taper Annular BOP | Annular BOP with tapered rubber packing element |
| Tapered Rubber Annular BOP | High-pressure annular BOP for heavy-duty drilling conditions |
| High Pressure Annular BOP | Annular BOP for high-pressure drilling and well control service |
| 10K Annular BOP | 10,000 psi annular blowout preventer for high-pressure drilling wells |
| 5K Annular BOP | 5,000 psi annular BOP for standard drilling BOP stack requirements |
| 13-5/8 Annular BOP | Common annular BOP size for drilling BOP stacks |
| 18-3/4 Annular BOP | Large bore annular BOP for offshore or high-spec rig applications |
| Annular BOP Packing Element | Replacement rubber packing element for annular BOP maintenance |
| Annular BOP Seal Kit | Seal kit for annular BOP repair and maintenance |
| Annular BOP Spare Parts | Spare rubber, seals, wear plates and related parts for annular BOPs |
Information Required for Quotation
To help SGPE select the correct Annular BOP Blowout Preventer and provide an accurate quotation, please send the following information:
| RFQ Information | Example |
| Required Model | FH35-35, FHZ35-70, or existing BOP model |
| Bore Size | 7-1/16″, 11″, 13-5/8″, 18-3/4″, 21-1/4″ |
| Rated Working Pressure | 2,000 psi, 3,000 psi, 5,000 psi, 10,000 psi |
| Rubber Structure | Spherical rubber or tapered rubber |
| Connection Type | Flanged, studded, bolted body, claw chuck structure |
| BOP Stack Drawing | Top and bottom interface, stack height, related equipment |
| Service Condition | Standard, high-pressure, sour service, H2S, CO2 |
| Required Documents | MTC, test report, COC, NACE declaration, O&M manual |
| Spare Parts | Packing element, seal kit, anti-dust ring, wear plate |
| Delivery Requirement | Quantity, destination port, delivery term, inspection requirement |
Why Choose SGPE
SGPE focuses on oilfield well control equipment, drilling pressure control products, API 16A BOP equipment, choke and kill manifold systems, wellhead equipment, and high-pressure oilfield components. In addition, SGPE supports buyers with model selection, technical communication, production control, document preparation, and after-sales coordination.
Buyers need more than a product name. They need correct model selection, clear interface confirmation, practical documents, reliable production control, and responsive support. Therefore, SGPE works with drilling contractors, oilfield service companies, rig manufacturers, well control equipment suppliers, and oilfield EPC projects to support annular BOP supply and technical coordination.
FAQ About API 16A Annular BOP Blowout Preventers
1. What is an Annular BOP Blowout Preventer?
An Annular BOP Blowout Preventer is a well control device used in oilfield drilling systems. It uses a rubber packing element to seal around drill pipe, tubing, casing, kelly, tool joints, and other oilfield tubulars. In suitable operating conditions, it can also close the open hole.
Drilling contractors usually install the annular BOP at the top of the BOP stack. As a result, its flexible sealing range makes it useful for kick control, well shut-in, stripping operations, pressure testing, workover, and well intervention service.
2. Where does an annular BOP install in a drilling BOP stack?
It normally installs at the top of the drilling BOP stack. In this position, it works together with ram BOPs, drilling spools, adapter spools, choke manifolds, kill manifolds, BOP control units, accumulator units, and choke and kill lines.
Therefore, the annular blowout preventer can provide the first flexible sealing barrier during drilling operations. The rig crew can seal around pipe quickly before using pipe ram, blind ram, shear ram, or other well control equipment according to the site procedure.
3. What is the difference between a spherical annular BOP and a taper annular BOP?
A spherical annular BOP uses a spherical rubber packing element. This design gives smooth rubber movement and helps the element close evenly around drill pipe, tubing, casing, and common oilfield tubulars. Therefore, it is often selected for standard land rig, offshore rig, workover, and well testing applications.
A taper annular BOP uses a tapered rubber packing element, wear plate, and supporting cylinder. As a result, this design gives stronger support during closing, so it is often selected for high-pressure wells, deep wells, heavy-duty drilling programs, and 10K annular BOP stack requirements.
4. Can an Annular BOP Blowout Preventer close on open hole?
Yes. It can close the open hole under suitable operating conditions. However, the rig crew should always follow the well control procedure, product manual, pressure rating, rubber element condition, and site safety rules.
Open-hole closing places high stress on the packing element. Therefore, operators should inspect the rubber element and related sealing areas after critical operations. For high temperature, sour service, frequent stripping, or repeated pressure cycles, a proper spare packing element plan becomes more important.
5. What pipe sizes can an annular blowout preventer seal around?
An annular blowout preventer can seal around different pipe sizes within its working range. It commonly seals around drill pipe, tubing, casing, kelly, tool joints, and selected irregular pipe profiles. Therefore, this wide sealing range makes it different from ram BOPs, which usually require specific ram blocks for specific pipe sizes.
The actual sealing range depends on the BOP model, bore size, packing element design, hydraulic closing pressure, pipe OD, rubber condition, and operating procedure. For replacement projects, buyers should confirm the existing model and packing element code before ordering spare parts.
6. What bore sizes and pressure ratings are available?
SGPE supplies common oilfield annular BOP bore sizes such as 7-1/16″, 9″, 11″, 13-5/8″, 16-3/4″, 18-3/4″, 20-3/4″, and 21-1/4″. These sizes cover many land drilling rigs, offshore drilling rigs, workover units, well testing packages, and drilling BOP stack configurations.
Common working pressure options include 2,000 psi, 3,000 psi, 5,000 psi, and 10,000 psi. However, the final model depends on bore size, well pressure, stack rating, rubber structure, hydraulic control volume, and project technical requirements.
7. How does the hydraulic control system close and open the annular BOP?
The BOP control unit sends hydraulic oil into the closing chamber when the rig crew closes the annular BOP. Then the piston moves upward and compresses the rubber packing element. As a result, the rubber moves inward and forms a seal around the pipe or wellbore.
During opening, the control system sends hydraulic oil into the opening chamber. After that, the piston moves back, the packing element releases the bore, and the wellbore opens again. For stable operation, buyers should check accumulator capacity, hydraulic working pressure, close volume, open volume, control line arrangement, and BOP control unit compatibility.
8. What is the recommended hydraulic pressure for sealing around pipe?
For many listed models, the recommended hydraulic pressure for sealing around pipe is ≤10.5 MPa / ≤1,524 psi. This value helps protect the rubber packing element while maintaining proper sealing performance during pipe sealing operations.
However, the final hydraulic pressure should follow the operation manual, site well control procedure, product model, pipe size, well pressure, and technical agreement. Excessive closing pressure may shorten rubber life, while insufficient pressure may affect sealing performance.
9. How should buyers select the correct Annular BOP Blowout Preventer?
Buyers should start with bore size and working pressure. Then they should confirm BOP stack rating, drilling program, well depth, formation pressure, pipe size range, sour service condition, temperature class, and connection type.
After that, buyers should choose between a Spherical Annular BOP and a Taper Annular BOP. A spherical model suits many standard drilling well control applications. By contrast, a tapered model suits high-pressure wells, 10,000 psi BOP stacks, deep wells, and heavy-duty oilfield service. For safer selection, buyers should provide a BOP stack drawing or existing BOP model.
10. What should buyers check when replacing an existing annular BOP?
For replacement projects, buyers should check the existing annular BOP model, bore size, pressure rating, top and bottom connection dimensions, ring gasket type, stud size, face-to-face dimension, and stack height. These details help avoid installation mismatch at the rig site.
In addition, buyers should confirm the rubber packing element type, spare part code, hydraulic close volume, open volume, control system capacity, and service environment. If the current unit works in H2S service or sour gas conditions, the replacement annular BOP should also meet the required sour service standard.
11. Does SGPE supply annular BOP spare parts and packing elements?
Yes. SGPE supplies spare parts for annular BOP maintenance and replacement. Common spare parts include spherical rubber packing elements, tapered rubber packing elements, seals, anti-dust rings, wear plates, supporting cylinders, and related seal kits.
A proper spare parts plan helps reduce rig downtime. In addition, harsh drilling fluid, high temperature, sour service, frequent stripping, pressure testing, and repeated closing cycles can wear the packing element faster. Therefore, buyers should prepare suitable rubber packing elements and seal kits according to the drilling schedule and site maintenance plan.
12. What documents and information should buyers provide before requesting a quotation?
To receive an accurate quotation, buyers should provide the required model, bore size, rated working pressure, rubber type, top and bottom connection type, BOP stack drawing, temperature class, material class, sour service requirement, quantity, spare parts list, destination, and delivery term.
In addition, SGPE can support common project documents such as material test certificates, hydrostatic test reports, dimensional inspection reports, certificate of conformity, NACE MR0175 declaration when required, operation manual, maintenance manual, packing list, and third-party inspection coordination. For inspection projects, buyers may request SGS, BV, ABS, DNV, TUV, or other approved inspection agencies according to the contract.
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SGPE supplies Annular BOP Blowout Preventers for oilfield drilling well control, BOP stack packages, workover pressure control systems, well testing operations, well intervention service, and high-pressure oilfield applications.
E-Mail:
info@sgpe.com
