FHZ43-21 16-3/4″ 3000psi Conical Annular BOP
锥形胶芯环形防喷器 | Annular Blowout Preventer
The CAMTOP FHZ43-21 is a high-performance conical annular blowout preventer designed for 16-3/4″ bore applications at 3,000 psi working pressure. Featuring a robust A1-type conical rubber packing element, this BOP delivers reliable wellbore sealing for drilling, workover, and well control operations. The unit is NACE MR-01-75 compliant for sour service (H2S) environments.
- ✓ Bore Size: 16-3/4″ (425.4 mm)
- ✓ Working Pressure: 3,000 psi (21 MPa)
- ✓ Sealing Type: Conical Packing Element (A1)
- ✓ H2S Service: NACE MR-01-75 Compliant
- ✓ Weight: 7,098 kg
Product Overview
The CAMTOP FHZ43-21 Conical Annular BOP is an A1-type annular blowout preventer designed to seal around various tubular shapes and sizes in the wellbore annulus. Equipped with a conical packing element, this BOP utilizes hydraulic pressure to drive the piston upward, compressing the packing element radially inward to achieve a tight seal around drill pipe, drill collars, casing, wireline, or to fully close on an open hole.
Built with a robust body and top cover connected via a reliable jaw-and-screw mechanism, the FHZ43-21 is engineered for easy on-site disassembly and maintenance. The unit features double U-type seals and drum-type seals on both piston and cover diameters, ensuring long service life under demanding drilling conditions.
The FHZ43-21 is designed as a transitional well control device — it is NOT intended for extended well shut-in. For prolonged shut-in operations, a ram-type BOP should be used. When closing on an empty hole, the maximum wellbore pressure must not exceed half of the rated working pressure (10.5 MPa / 1,500 psi).
All CAMTOP annular BOPs are manufactured under strict quality control, hydrostatically tested to 31.5 MPa (4,500 psi), and delivered with complete documentation including material certifications, test reports, and spare parts lists. The metal body is rated T20 for operating temperatures from -29°C to 121°C.
Technical Specifications
| Parameter | Metric | Imperial |
|---|---|---|
| Model | FHZ43-21 (Conical Annular BOP, A1 Type) | |
| Nominal Bore Diameter | 425.4 mm | 16-3/4″ |
| Rated Working Pressure | 21 MPa | 3,000 psi |
| Hydrostatic Test Pressure | 31.5 MPa | 4,500 psi |
| Hydraulic Rated Working Pressure | 21 MPa | 3,000 psi |
| Recommended Closing Pressure (on Pipe) | 8.4 ~ 10.5 MPa | 1,200 ~ 1,500 psi |
| Max Working Pressure (closed on Open Hole) | 10.5 MPa | 1,500 psi |
| Sealing Range | 0 ~ 425.4 mm | 0 ~ 16-3/4″ |
| Max Oil Volume to Open | 84 L | 22.2 gal |
| Max Oil Volume to Close | 118 L | 31.2 gal |
| Piston Max Stroke | 287 mm | 11.3″ |
| Lifting Eye Capacity (x2) | 25,000 kg each | 55,116 lbs each |
| Hydraulic Connection | NPT 1-1/2″ | |
| Top Connection | Studded, 16-3/4″ – 3,000 psi, 6B R66 | |
| Bottom Connection | Flange, 16-3/4″ – 3,000 psi, 6B R66 | |
| Overall Weight | 7,098 kg | 15,648 lbs |
| Overall Dimensions (L x W x H) | 1,598 x 1,598 x 1,553 mm | |
| Metal Temperature Rating | T20 (-29°C to 121°C / -20°F to 250°F) | |
| Sour Service Compliance | NACE MR-01-75 (H2S Resistant) | |
Key Features & Design Advantages
⚙ Simple & Reliable Structure
The FHZ43-21 features a minimal-component design with only 22 major part types. The top cover connects to the body via a jaw-and-screw mechanism, enabling rapid on-site disassembly without special tools. Fewer parts translate to higher reliability and lower maintenance costs.
🛠 Lip-Type Sealing System
Double U-type lip seals are deployed on both the piston small OD and piston large OD, as well as the cover bore. These seals are self-energizing — wellbore pressure assists in creating a tighter seal, reducing the required hydraulic closing pressure and extending seal life.
☢ H2S / Sour Service Ready
All wetted metallic materials comply with NACE MR-01-75 standards for sour gas environments. The conical packing element is formulated to resist hydrogen sulfide degradation, making the FHZ43-21 suitable for the most demanding H2S well control applications.
🔌 Wellbore Pressure-Assisted Sealing
In the closed position, wellbore pressure acting on the upper annular area of the piston chamber pushes the piston further upward, enhancing the packing element seal. This pressure-assisted design improves sealing reliability while reducing the hydraulic control pressure required.
🔧 Easy Packing Element Replacement
The conical packing element can be replaced even with drill pipe in the hole. Using the cut-and-replace method, a sharp cutting tool (lubricated with soapy water) is used to split the old element between any two support ribs. The new element is similarly cut, installed, and the cover re-secured — minimizing NPT.
🔋 Piston Stroke Monitoring
A measurement port on the top cover allows operators to monitor piston stroke using a thin rod and steel ruler. When the piston stroke reaches 287 mm (max), the packing element is nearing end of life and should be replaced. Reference value when fully open: Lopen = 390 mm.
Working Principle
Closing Sequence
When a well kick is detected and the well must be shut in, high-pressure hydraulic oil from the control system enters the lower hydraulic port on the BOP body and flows into the closing chamber beneath the piston. This hydraulic pressure drives the piston upward, which in turn forces the conical packing element to move radially inward toward the center. The steel support ribs converge, compressing the rubber between them to form a tight seal around the drill string — or to fully close on an open wellbore.
Opening Sequence
To open the BOP, hydraulic control pressure is directed to the upper hydraulic port, entering the opening chamber above the piston. This pressure drives the piston downward. The conical packing element, relying on its own elasticity, retracts back to its original position, opening the wellbore. After each opening cycle, operators should verify that the packing element has fully retracted to prevent drill string damage.
Applications
Pipe Sealing
Seals around various drill pipe sizes, drill collars, kelly, casing, and wireline
Full Bore Closure
Complete shut-off on open hole (max 10.5 MPa / 1,500 psi)
Stripping Operations
Supports snubbing/stripping with buffer accumulator, 18°/35° tool joints
Well Control
Primary well control device used in conjunction with ram BOPs for kick management
Manufacturing & Production Gallery
Behind-the-scenes views of CAMTOP’s precision manufacturing facility, where every FHZ43-21 annular BOP undergoes rigorous quality control at each production stage.
BOP Body Precision Machining
Piston & Packing Element Assembly
Final Assembly & Hydrostatic Testing (4,500 psi)
Completed FHZ43-21 at CAMTOP Workshop
Maintenance & Service Guidelines
After Each Well Service
- Perform a thorough cleaning and inspection of all components
- Replace any damaged or worn parts immediately
- Apply synthetic composite aluminum-based grease to non-painted surfaces
- Apply molybdenum disulfide thread compound to all threaded connections
- Check all seal surfaces for scoring or damage; repair if necessary
Rubber Component Storage
- Store in a dark, dry indoor environment at 15°C ~ 25°C
- Keep humidity below 80%; avoid direct sunlight and heating equipment
- Keep away from high-voltage electrical equipment (ozone generation)
- Store in a relaxed state — no bending, twisting, compression, or hanging
- Maximum storage life under normal conditions: 2 years
Troubleshooting Quick Guide
- BOP leaks under well pressure: Cycle BOP open/close several times. If leak persists or support ribs have converged, replace packing element.
- BOP won’t open after closing: Packing element may be deformed/aged. Clean or replace element.
- Sluggish operation: Check for hydraulic oil leaks, dirt blockages. Purge control lines with compressed air before connection.
Frequently Asked Questions
Q: What is the maximum wellbore pressure when closing the FHZ43-21 on an open hole?
When closing on an empty hole (no drill pipe present), the maximum wellbore pressure must not exceed 10.5 MPa (1,500 psi), which is half the rated working pressure of 21 MPa (3,000 psi). For full-rated pressure containment, a ram-type BOP should be used for extended shut-in periods.
Q: Can the packing element be replaced while drill pipe is in the hole?
Yes. The FHZ43-21 conical packing element can be replaced with drill pipe in the hole using the cut-and-replace method. Use a sharp cutting blade (lubricated with soapy water — never use a saw or dull tool) to cut the new element between any two support ribs with a clean, flat cut surface. Similarly cut and remove the old element, then install the new cut element. However, you must first confirm that the drill string is reliably sealed by a ram BOP and there is no wellbore pressure or pressure buildup tendency.
Q: Is the FHZ43-21 suitable for H2S (sour gas) service?
Yes. All wetted metallic materials in the CAMTOP FHZ43-21 annular BOP comply with NACE MR-01-75 standards for sour service environments. The rubber packing element is also formulated for resistance to hydrogen sulfide (H2S) degradation, making this BOP suitable for drilling operations in sour gas fields.
Q: How do I know when to replace the packing element?
Monitor the piston stroke through the measurement port on the top cover. Use a thin rod and steel ruler. The reference measurement when fully open is Lopen = 390 mm. After closing, measure Lclosed. The difference (Lopen – Lclosed) is the piston stroke. When this value reaches the maximum of 287 mm, the packing element is approaching the end of its service life and should be replaced promptly.
Q: What hydraulic control pressure is recommended for closing the FHZ43-21?
The recommended hydraulic control pressure for closing on pipe is 8.4 ~ 10.5 MPa (1,200 ~ 1,500 psi). For closing on an open hole, the recommended hydraulic control pressure is ≤ 10.5 MPa (≤ 1,500 psi). During pressure testing and normal closing operations, use the lowest possible control pressure to extend packing element service life. For stripping/snubbing operations, gradually reduce closing pressure until a slight leak appears — this lubricates the contact surface and prevents overheating.
Q: What are the bolt tightening torque specifications for flange connections?
Flange bolts should be tightened evenly in a diagonal pattern. Refer to the bolt torque table for specific values. For example: M30×3 bolts: 930 N·m; M36×3: 1,737 N·m; M42×3: 2,910 N·m; M48×3: 4,516 N·m. For imperial: 1-1/4″-8UN: 953 ft·lb; 1-1/2″-8UN: 1,676 ft·lb. After pressure testing, re-tighten all connecting bolts to eliminate uneven tension.
Ordering Information
When ordering the CAMTOP FHZ43-21 Annular BOP or any spare parts, please specify the following:
- Model & Size: FHZ43-21 — 16-3/4″ bore, 3,000 psi working pressure
- Packing Element Type: Conical (Type A1)
- Connection Specifications: Bottom flange size, working pressure, ring gasket groove (default: 16-3/4″ – 3,000 psi, 6B R66)
- Top Connection: Studded, 16-3/4″ – 3,000 psi, 6B R66
- Temperature Rating: Metal class (T20) and rubber seal class
- Ring Groove Overlay: Specify if stainless steel weld overlay is required on ring grooves
- Sour Service: Confirm NACE MR-01-75 requirement
- Spare Parts: Quantity and part numbers for additional spare parts beyond standard kit
- Special Requirements: Any additional operational or installation requirements
Get a Quote for FHZ43-21 Annular BOP
Contact our sales team for pricing, lead time, and technical consultation. We provide comprehensive after-sales support including on-site commissioning, spare parts supply, and maintenance training.
Phone / WhatsApp
+86-18621723891
SALES@CPOSL.COM
Website
www.camtop-oilfieldtools.com
CAMTOP Oilfield Tools | Professional BOP Manufacturer | API Certified Quality Management