API 16A Double Ram Blowout Preventer for Drilling Well Control

Description

Goldenman API 16A Double Ram Blowout Preventers combine two independently operated ram cavities within one pressure-containing body.

Each cavity can be configured with fixed pipe rams, variable-bore rams, blind rams, shear rams or blind-shear ram assemblies according to the well program and required emergency functions.

Available configurations cover nominal bore sizes from approximately 4-1/16 to 26-3/4 inches and rated working pressures from 2,000 to 20,000 psi.

Standard 5,000 psi 2FZ-series models are available for conventional drilling and workover operations. High-pressure and ultra-high-pressure configurations can be engineered for deep wells, ultra-deep wells, HPHT wells, and unconventional oil and gas projects.

Each Goldenman Double Ram BOP is configured according to the BOP stack bore, pressure rating, tubular program, ram arrangement, control-system capacity, material class, temperature, and H₂S conditions.

Product Short Description

Goldenman Double Ram BOPs provide two independent well-control barriers within one compact BOP body.

The upper and lower ram cavities can perform different sealing or emergency functions, allowing one BOP to seal around tubulars, close an open wellbore or shear specified pipe when equipped with the appropriate qualified ram assemblies.

Flanged or studded connections, manual or hydraulic locking systems, and project-specific side outlets are available.

Product Highlights

• Manufactured to applicable API Spec 16A requirements
• API-certified Ram BOP equipment
• Two independently operated ram cavities
• Nominal bore ranges from 4-1/16 to 26-3/4 in
• Working pressure ranges from 2,000 to 20,000 psi
• Standard and ultra-high-pressure configurations
• Fixed pipe, variable-bore, blind, and shear ram options
• Manual or hydraulic ram locking
• Flanged or studded top and bottom connections
• Side outlets are available according to the stack design
• Rotary or linear side-door configurations
• Replaceable front packers and top seals
• Sour-service and low-temperature material options
• Factory pressure and functional testing
• Project-specific API and inspection documentation
• Ram blocks, sealing parts, and overhaul kits available

What Is a Double Ram BOP?

A Double Ram Blowout Preventer contains two vertically arranged ram cavities within one BOP body.

Each cavity contains two opposed ram assemblies. Hydraulic pressure moves the rams toward the center of the bore to perform the required sealing or shearing function.

The two cavities can be equipped with different ram types, allowing the BOP to perform two independent well-control functions.

Common configurations include:

Upper Ram Cavity	Lower Ram Cavity	Typical Function
Fixed pipe ram	Fixed pipe ram	Seals two different tubular sizes
Variable-bore ram	Blind ram	Seals a tubular range and closes an open bore
Fixed pipe ram	Shear ram	Routine pipe sealing plus emergency shearing
Variable-bore ram	Blind-shear ram	Flexible tubular sealing plus emergency isolation
Pipe ram	Pipe ram of the same size	Two independent sealing barriers

The final arrangement must follow the approved BOP stack design and well-control procedure.

Main Applications

Goldenman Double Ram BOPs can be configured for:

• Land drilling rigs
• Offshore drilling systems
• Workover rigs
• Well servicing operations
• Deep and ultra-deep wells
• HPHT drilling
• Unconventional oil and gas wells
• Pressure control around drill pipe
• Pressure control around tubing or casing
• Open-bore well shut-in
• Emergency tubular shearing
• BOP stack replacement
• New well-control equipment packages

The Double Ram BOP should be integrated with the appropriate Annular BOP, drilling spool, control system, choke and kill manifold and high-pressure control lines.

General Technical Specifications

Parameter	Available Specification
Product name	Double Ram Blowout Preventer
Applicable standard	API Spec 16A, applicable current edition
API product category	Ram BOP
Number of ram cavities	Two
Nominal bore range	Approximately 4-1/16–26-3/4 in
Working pressure	2,000–20,000 psi
Operation	Hydraulic
Locking method	Manual or hydraulic
Ram types	Pipe, variable-bore, blind, shear or blind-shear
Side-door design	Rotary or linear-opening configuration
Top connection	Flanged or studded
Bottom connection	Flanged or studded
Side outlets	Available according to approved design
Material class	According to the API and project specification
Temperature class	According to the API and operating conditions
Sour service	Available according to specified H₂S conditions
Performance requirement	Project-specific PR level
Certification	Applicable API certificate
Inspection	Factory and third-party inspection as specified

Final dimensions, weight, operating volumes, and connection details are governed by the approved manufacturing datasheet and general arrangement drawing.

Standard 5,000 psi 2FZ-Series Models

Model	Nominal Bore	Working Pressure	Locking Method	Reference Dimensions
2FZ18-35	180 mm / 7-1/16 in	35 MPa / 5,000 psi	Hydraulic	1450 × 380 × 620 mm
2FZ23-35	230 mm / 9 in	35 MPa / 5,000 psi	Hydraulic	2030 × 870 × 830 mm
2FZ28-35	280 mm / 11 in	35 MPa / 5,000 psi	Hydraulic	2110 × 870 × 830 mm
2FZ35-35	350 mm / approximately 13-5/8 in	35 MPa / 5,000 psi	Hydraulic	2400 × 920 × 1360 mm

These dimensions are preliminary reference values. Final connection style, ram arrangement, hydraulic-port position, and equipment weight must be confirmed through the current product drawing.

Extended Bore and Pressure Availability

Nominal Bore	Representative Pressure Ratings
4-1/16 in	Up to 20,000 psi
7-1/16 in	5,000 and up to 20,000 psi
9 in	5,000 psi and project-specific configurations
11 in	3,000, 5,000, 10,000, 15,000 and 20,000 psi
13-5/8 in	3,000, 5,000, 10,000 and 15,000 psi
16-3/4 in	3,000, 5,000 and 10,000 psi
18-3/4 in	5,000, 10,000 and up to 20,000 psi
20-3/4 in	3,000 psi and project-specific configurations
21-1/4 in	2,000, 5,000 and 10,000 psi
26-3/4 in	2,000 and 3,000 psi

Not every pressure, bore, connection and ram combination is available as one standard product.

The required configuration must be confirmed through a technical review and an approved drawing.

Available Ram Types

Fixed Pipe Rams

Fixed pipe rams are designed to seal around one specified tubular outside diameter.

They are appropriate when:

• The tubular size is known
• Maximum sealing contact is required
• The BOP stack uses a defined drill pipe or tubing program
• Dedicated RAM inventory is available on-site

The ram size must match the actual tubular OD at the sealing position.

Variable-Bore Rams

Variable-bore rams can seal around a qualified range of tubular diameters.

They may be selected when:

• Multiple drill pipe sizes are used
• A tapered drillstring is planned
• Ram-change frequency must be reduced
• Greater operating flexibility is required

The qualified sealing range must be confirmed for the exact ram assembly and BOP model.

Blind Rams

Blind rams are designed to close and seal an open wellbore when no tubular is positioned across the ram cavity.

Blind rams are not intended to close over drill pipe, tubing, wireline, or other equipment.

Shear Rams

Shear rams are designed to cut specified tubulars under qualified conditions.

Selection requires complete tubular information, including:

• Outside diameter
• Wall thickness
• Steel grade
• Material strength
• Connection type
• Tool-joint position
• Tubular condition
• Required shearing pressure

A shear ram should never be selected using only the nominal drill pipe size.

Blind-Shear Rams

A blind-shear ram combines tubular shearing and subsequent open-bore sealing functions.

Both capabilities must be verified using the actual tubular and BOP operating conditions.

Ram Packers and Top Seals

Each ram sealing assembly normally includes:

• Metallic ram block
• Front packer
• Top seal
• Side or secondary sealing components
• Retaining hardware

The front packer forms the primary seal around the tubular or across the open bore.

The top seal closes the pressure path between the ram assembly and the upper ram cavity.

Replacement components must match:

• BOP manufacturer
• BOP model
• Ram cavity
• Ram block design
• Tubular size or range
• Working pressure
• Temperature
• Drilling-fluid chemistry
• H₂S conditions

Ram packers and top seals should not be ordered using only the BOP bore.

Manual and Hydraulic Locking Systems

Manual Locking

Manual locking uses mechanical screws or lock shafts to hold the rams in the closed position.

It may be selected where:

• A simple mechanical lock is preferred
• Local access is available
• The operating procedure permits manual engagement
• A hydraulic locking circuit is not required

Manual locking is separate from the hydraulic force used to move the ram.

Hydraulic Locking

Hydraulic locking allows the lock mechanism to be operated remotely through the BOP control system.

It may be preferred where:

• Remote operation is required
• Access to the BOP stack is restricted
• Faster locking and unlocking are required
• The equipment is integrated with a larger control system

The control unit must include the correct hydraulic functions and fluid capacity for the locking circuits.

Side-Door Configurations

Rotary Side Door

A rotary or hinged side door swings outward to provide access to the ram cavity.

The installation must provide sufficient side clearance for:

• Full door opening
• Ram block removal
• Seal replacement
• Inspection
• Maintenance tools

Linear-Opening Side Door

A linear side-door design moves outward along a controlled path.

It may be selected where the approved BOP design requires a different maintenance arrangement or where lateral clearance must be managed.

The side-door design affects:

• Overall BOP width
• Maintenance clearance
• Ram-change procedure
• Hydraulic connections
• Replacement compatibility

Optional Side Outlets

Side outlets can be incorporated where required by the BOP stack design.

They may provide connections for:

• Choke line
• Kill line
• Pressure monitoring
• Well circulation
• Controlled bleed-off

The buyer should specify:

• Outlet quantity
• Outlet size
• Pressure rating
• Flanged, studded or hub connection
• Outlet orientation
• Ring-gasket specification
• Required valves

A side outlet must not be treated as a complete choke or kill function unless the connected valves and flowline are correctly rated.

How to Select the Correct Double Ram BOP

1. Confirm Bore Size

The BOP bore must match the wellhead and adjacent stack equipment.

Also, confirm the largest equipment passing through the bore:

• Tool joints
• Drill collars
• Casing couplings
• Completion assemblies
• Bottom-hole tools
• Workover equipment

2. Confirm Working Pressure

Selection should consider:

• Maximum anticipated surface pressure
• Shut-in pressure
• Well-control design pressure
• BOP stack rating
• Pressure-test requirement
• Regulatory requirements
• Project design margin

The complete BOP stack must have compatible pressure ratings.

3. Define Both Ram Functions

Specify the exact function required in the upper and lower cavities.

Do not order only “one Double Ram BOP” without defining:

• Pipe size
• Variable-bore range
• Blind ram requirement
• Shear ram requirement
• Preferred upper and lower positions

4. Confirm Connections

Provide:

• Top connection
• Bottom connection
• Flanged or studded design
• Nominal bore
• Pressure rating
• Ring-gasket numbers
• Stud specifications
• Stack height limitations

5. Verify the Control-System Capacity

The BOP control unit must provide sufficient pressure and usable hydraulic volume for:

• Upper ram opening and closing
• Lower ram opening and closing
• Hydraulic locks
• Side-outlet valves
• Shear operation
• Required emergency sequence

Opening and closing volumes must be taken from the final model datasheet.

Shear Ram Engineering Review

A statement such as “the BOP must shear 5-inch drill pipe” is not enough to approve the configuration.

Goldenman requires:

• Pipe OD
• Nominal weight
• Wall thickness
• Steel grade
• Actual material strength
• Tool-joint OD
• Tool-joint location
• Pipe condition
• Required shear position
• Maximum available hydraulic pressure
• BOP control-line pressure loss

The review determines whether the proposed ram, BOP operator and control unit can generate sufficient shearing force.

Physical shear testing can be performed when required by the contract and approved test procedure.

Ultra-High-Pressure Double Ram BOP

Ultra-high-pressure configurations are intended for demanding well-control environments such as:

• Deep and ultra-deep drilling
• HPHT wells
• Unconventional reservoirs
• High-pressure gas wells
• Sour-gas projects
• Extended-reach drilling

The design review may include:

• High-strength and high-toughness body materials
• Controlled heat treatment
• Pressure-containing bolting
• H₂S-resistant material selection
• Internal corrosion protection
• High-pressure sealing systems
• Qualified ram packers
• Increased structural and fatigue evaluation
• Project-specific testing and documentation

The final 15,000 or 20,000 psi configuration must be engineered for the selected bore and connection arrangement.

H₂S and Sour-Service Selection

For sour-service projects, provide:

• H₂S concentration or partial pressure
• CO₂ concentration
• Operating pressure
• Operating temperature
• Chloride content
• Drilling-fluid chemistry
• Applicable NACE MR0175/ISO 15156 requirements
• Required material class

The technical review should cover:

• BOP body
• Bonnet or side doors
• Rams
• Bolting
• Hydraulic cylinders
• Internal components
• Front packers
• Top seals
• Other elastomeric seals

A general request for “H₂S-resistant BOP” does not provide enough information for final material selection.

Replacement and Interchangeability

A replacement Double Ram BOP should not be ordered using only bore and working pressure.

Provide:

• Existing manufacturer
• Model and serial number
• Manufacturing year
• Top connection
• Bottom connection
• Ring-gasket numbers
• Overall dimensions
• Stack height
• Ram cavity arrangement
• Side-outlet locations
• Hydraulic port locations
• Opening and closing volumes
• Locking method
• Ram block part numbers
• Existing BOP control unit
• General arrangement drawing

Two 13-5/8 in, 10,000 psi Double Ram BOPs may not be directly interchangeable because their height, connections, side doors, hydraulic interfaces and ram assemblies can differ.

Manufacturing and Quality Control

Goldenman quality-control procedures may include:

• Material certificate verification
• Heat-number traceability
• Chemical and mechanical property review
• Heat-treatment record verification
• Dimensional inspection
• Bore and ram cavity inspection
• Connection and ring-groove inspection
• Hardness testing
• Ultrasonic examination
• Magnetic-particle or liquid-penetrant examination
• Pressure-containing bolting verification
• Ram block and seal inspection
• Hydraulic opening and closing test
• Locking-system function test
• Body hydrostatic test
• Ram sealing and pressure-holding test
• External leakage inspection
• Product marking verification
• Coating and preservation inspection
• Final documentation review

The final inspection plan follows the approved API quality plan, product configuration and purchase order.

Factory Acceptance Test

The agreed FAT may include:

• Approved drawing review
• Bill of materials verification
• Material traceability review
• Dimensional inspection
• Connection inspection
• Ram installation verification
• Hydraulic opening and closing
• Manual or hydraulic lock testing
• Body hydrostatic test
• Pipe ram sealing test
• Blind ram sealing test
• Variable-bore ram test
• Shear-function test when contractually required
• Pressure-holding test
• External leakage inspection
• Functional cycling
• Product marking inspection
• Coating inspection
• Documentation review

The test pressure, holding time, test tubular and witness points must be agreed before production.

Available Documentation

The documentation package can include:

• API certificate
• Certificate of Conformity
• Approved product datasheet
• General arrangement drawing
• BOP stack interface drawing
• Material certificates
• Heat-treatment records
• NDE reports
• Hardness report
• Bolting documentation
• Dimensional inspection report
• Connection inspection report
• Hydrostatic test report
• Ram sealing test report
• Hydraulic functional test report
• Shear test report when required
• Ram and seal identification list
• Operation and maintenance manual
• Recommended spare-parts list
• Packing list
• Third-party inspection report

Frequently Asked Questions

What is the advantage of a Double Ram BOP over a Single Ram BOP?

A Double Ram BOP provides two independent ram cavities in one body.

This allows two different functions—such as pipe sealing and blind or shear isolation—without installing two separate Single Ram BOP bodies. The final benefit depends on stack height, weight, maintenance access and required redundancy.

Which ram arrangement should be selected?

The arrangement must follow the tubular program and emergency well-control philosophy.

A common configuration uses pipe or variable-bore rams in one cavity and blind-shear rams in the other. Projects using several tubular sizes may require variable-bore rams or two different fixed pipe ram sizes.

Can a variable-bore ram replace all fixed pipe rams?

No.

A variable-bore ram seals only within its qualified OD range. Fixed pipe rams may provide a more dedicated sealing geometry for one tubular size.

The decision should consider the complete drillstring and operating procedure.

Can a shear ram cut any drill pipe?

No.

Shear capability depends on tubular OD, wall thickness, grade, material strength, connection location, BOP operator force and available hydraulic pressure.

Tool joints normally require a separate and more demanding evaluation.

Can a 3,000 psi BOP control unit operate a 15,000 or 20,000 psi Double Ram BOP?

Possibly.

The 15,000 or 20,000 psi rating refers to wellbore pressure containment. The BOP hydraulic operating pressure is a separate specification.

The control unit must be checked against the required operator pressure, closing volume, wellbore pressure and shear requirements.

Can a Goldenman Double Ram BOP replace a Shaffer- or Cameron-style unit?

A dimensional replacement may be engineered after the exact model, connections, stack height, hydraulic interfaces, side outlets and ram arrangement have been verified.

Brand names should only be used to identify compatibility requirements. Goldenman replacement products are not represented as original products from another manufacturer.

Why are BOP opening and closing volumes important?

These values determine the usable hydraulic fluid required from the BOP control unit.

They affect accumulator sizing, emergency operating capacity and response time. Final volumes must be taken from the selected BOP datasheet.

What should be checked for an H₂S-service Double Ram BOP?

The review should include the body, bonnets, rams, bolting, pressure-containing components, packers, top seals and hydraulic seals.

Actual H₂S partial pressure, temperature and fluid chemistry are required for material selection.

What spare parts should be purchased with a Double Ram BOP?

A project package may include:

• Complete spare ram assemblies
• Front packers
• Top seals
• Bonnet or door seals
• Hydraulic cylinder seal kits
• Locking-system components
• Ring gaskets
• Studs and nuts
• Hydraulic fittings

Spare quantities should reflect the well program and local replacement-part availability.

What documents should be supplied with an API 16A Double Ram BOP?

The agreed package may include the API certificate, material certificates, NDE reports, dimensional inspection, hydrostatic testing, ram sealing tests, functional tests and Certificate of Conformity.

Documentation requirements should be confirmed before manufacturing.

Information Required for Quotation

Please provide:

• Required nominal bore
• Rated working pressure
• Upper connection
• Lower connection
• Ring-gasket specifications
• Upper ram type
• Lower ram type
• Tubular sizes to be sealed
• Variable-bore sealing range
• Blind-sealing requirement
• Shearing requirement
• Tubular OD
• Tubular wall thickness
• Tubular grade
• Tool-joint information
• Side-outlet requirements
• Manual or hydraulic locking
• Side-door preference
• BOP stack configuration
• Available control pressure
• Required opening and closing sequence
• Operating temperature
• Drilling-fluid type
• H₂S and CO₂ conditions
• Applicable NACE requirements
• Required spare ram and seal package
• API certificate requirements
• FAT requirements
• Third-party inspection requirements
• Destination country
• Required delivery schedule

For replacement equipment, also provide the existing nameplate, general arrangement drawing, hydraulic interfaces and site photographs.

Request a Technical Quotation

Goldenman supplies API 16A Double Ram Blowout Preventers for drilling, workover, HPHT and ultra-high-pressure well-control systems.

Available configurations cover bore sizes from approximately 4-1/16 to 26-3/4 inches and pressure ratings from 2,000 to 20,000 psi.

Send your bore, pressure, stack connections, upper and lower ram functions, tubular data and service conditions to:

Email: info@goldenman.com

Goldenman will review the BOP stack requirements and prepare the recommended model, ram configuration, general arrangement drawing and commercial quotation.