Order Trunnion Mounted Ball Valves for Oil Pipeline Project | Full Production and Delivery Timeline

The 16-to-24-week range is most useful for early planning of a small or medium order, such as 1 to 10 valves using common carbon steel materials, standard soft seats, routine production tests, and no major design changes after order placement. It is a planning example, not an API, ISO, or ASME requirement.

The purchase order should define a clear starting date, called Day 0. Day 0 may be the date the supplier accepts the purchase order, receives the advance payment, closes the main technical questions, or receives approval to buy long-lead materials.

The contract must also define the delivery point. Factory completion, factory release, EXW availability, handover to the carrier, vessel departure, port arrival, customs release, and delivery to site are different milestones.

Confirm the Pipeline Service

Do not select a pipeline valve from nominal size and pressure class alone. The manufacturer needs the real operating conditions to choose the body, seats, seals, ball surface, gearbox, and actuator.

Provide the following information with the request for quotation:

• Fluid type, such as crude oil, diesel, gasoline, condensate, or multiproduct service
• Design pressure and normal operating pressure
• Maximum pressure difference during opening and closing
• Design temperature and minimum design metal temperature
• Minimum and maximum ambient temperature
• Water, sand, scale, wax, or other contaminants
• H₂S content, chloride level, and presence of free water
• Flow direction and operating frequency
• Required opening and closing time
• Aboveground or underground installation
• Hazardous-area classification
• Pigging and inline inspection requirements
• Expected operating life

Normal operating pressure and maximum closing pressure difference are not the same. A valve may normally operate at 60 bar but need to close against a higher pressure difference during an emergency. If the actuator is sized only for normal operation, it may not close when isolation is needed.

The fluid description should be more specific than “oil.” Crude oil, diesel, gasoline, condensate, and heavy fuel oil may have different effects on polymer seats and elastomer seals. Identify free water, dissolved gas, aromatic hydrocarbons, solids, cleaning chemicals, and pipeline additives where relevant.

For buried valves, also provide:

• Burial depth
• Soil and groundwater conditions
• Stem-extension height
• Pipeline coating type
• Cathodic-protection details
• Required position of drain, vent, and sealant lines

A valve operated weekly has different wear and torque conditions from an emergency shutdown valve that may stay in one position for several years. For long-idle valves, ask the manufacturer to consider deposits, seat aging, seal compression, temperature, and higher breakaway torque.

For more selection details, see the API 6D trunnion mounted ball valve guide.

Choose the Valve Construction

In a trunnion mounted ball valve, the ball is supported at the top and bottom. The seats move toward the ball to form the seal. This construction is commonly used for large sizes, high pressures, high pressure differences, remote operation, buried pipelines, and piggable mainlines.

The purchase specification should state:

• Two-piece or three-piece body
• Bolted or fully welded body
• Side-entry or top-entry construction
• Full or reduced bore
• Flanged or butt-weld ends
• Soft or metal seats
• Manual, electric, hydraulic, pneumatic, or gas-over-oil operation

A fully welded valve has fewer external body joints and is often used for buried mainline service. However, internal repairs are more difficult, and the manufacturer must control welding, heat input, dimensional distortion, and nondestructive examination.

A top-entry valve may allow the seats and ball to be removed from above without taking the complete valve out of the pipeline. This only helps when the site has enough lifting space, safe access, drainage, and pressure isolation.

A side-entry valve is usually easier to manufacture and repair in a workshop, but major internal work may require removal from the pipeline. Compare the options in this side-entry versus top-entry ball valve guide.

Also confirm:

• Blowout-resistant stem design
• Antistatic device
• Emergency stem and seat sealant injection
• Drain and vent connections
• Lifting lugs and support feet
• Position indicator and locking device
• Stem-extension construction
• Maximum permitted external pipe loads

Define the Bore

Do not write only “full bore.” State the required minimum finished bore and ask the manufacturer to show the complete flow path on the drawing.

Check the valve bore against:

• Actual pipe inside diameter
• Pipe wall thickness and tolerance
• Internal coating thickness
• Ball-port diameter
• Seat-opening diameter
• Butt-weld-end transition
• Pig and inline inspection-tool diameter
• Maximum permitted internal step and misalignment

A valve described as full bore may not exactly match a thick-wall or internally coated pipeline. The approved drawing should show the minimum bore through the ball, both seat openings, body, and end connections.

For piggable pipelines, the operator or inspection-tool supplier should confirm the allowed bore reduction, ovality, internal step, protrusion, and offset.

Freeze the bore before major body materials are ordered. A change made after forging production starts may add about 6 to 16 weeks if replacement material is required. This is a project-planning range and depends on size, material, and forging availability.

Define the Seat Function

Seat design controls sealing direction and the way pressure is released from the body cavity.

Common arrangements include:

• Two single-piston-effect or self-relieving seats
• Two double-piston-effect seats
• One self-relieving seat and one double-piston-effect seat

SPE and DPE describe how an individual seat reacts to pressure. DBB and DIB describe the isolation function of the complete valve. They are not interchangeable terms.

A self-relieving seat can allow excess cavity pressure to return to the pipeline when the required pressure difference is reached. A double-piston-effect seat can seal with pressure from either direction, but it may trap pressure in the body cavity. If the cavity cannot relieve automatically, an external relief system may be needed.

Do not order a valve using only “DBB” or “DIB.” State exactly what the valve must do:

• Seal against upstream pressure
• Seal against downstream pressure
• Allow each seat to be tested separately
• Allow the cavity to be vented while both sides remain pressurized
• Relieve cavity pressure toward a stated side
• Maintain isolation if pressure is lost on one side

Ask for a seat schematic showing pressure areas, seat movement, relief direction, drain and vent paths, and any required valve orientation.

Soft seats normally provide tighter shutoff and lower torque. Metal seats may be needed for high temperatures, abrasive particles, erosion, or frequent cycling. A metal-seated valve does not automatically provide zero leakage; the purchase order must state the allowed leakage rate and test method.

Select the Materials

The bill of materials should identify the body, closure, ball, stem, trunnion, seat rings, seat inserts, seals, bearings, springs, bolting, drains, vents, fittings, and stem extension.

For each part, require:

• Material grade and product form
• Heat-treatment condition
• Hardness limit
• Impact-test requirement
• Coating or weld overlay
• Required inspection and certificate

Material substitutions should need written approval. A substitute material must be checked for pressure capacity, temperature, corrosion, hardness, welding, seal compatibility, and actuator torque.

Body: State whether castings, forgings, or fabricated construction are acceptable. Large forgings may give good control of material properties but can add several weeks to the schedule. Where low temperatures apply, define the impact-test temperature and required absorbed energy.

Ball: The ball may use polished stainless steel, electroless nickel plating, stainless overlay, tungsten carbide, chromium carbide, or another qualified surface. Hardness alone is not enough. Check thickness, porosity, bond quality, roughness, roundness, and permitted repair.

Seats: PTFE, reinforced PTFE, nylon, PEEK, and other polymers have different pressure, temperature, chemical, and torque limits. Require the exact grade or compound. A seat-material change can alter leakage and torque, so actuator sizing must be checked again.

Seals: Names such as NBR, HNBR, FKM, or FFKM do not fully define performance. Require the exact compound, hardness, service-temperature range, fluid compatibility, rapid-gas-decompression qualification where needed, shelf life, and batch traceability.

For high-pressure forged configurations, review the available API 6D forged ball valve range. For abrasive or high-temperature service, see the forged metal-seated ball valve range.

Handle Sour Service

“NACE compliant” is not a complete material requirement. The buyer must provide the actual H₂S environment and specify which material standard applies.

ISO 15156 covers material selection for defined H₂S-containing environments in oil and gas production and natural-gas sweetening. It should not automatically be applied to every refinery or downstream pipeline without checking the project scope.^[1]

Provide:

• H₂S partial pressure
• Total pressure and temperature
• Presence of free water
• Chloride concentration and pH, where known
• Maximum material and weld hardness
• Bolting restrictions
• PMI and NDE requirements

The sour-service material list should cover the body, stem, ball, bolting, springs, weld overlay, drains, vents, and pressure-containing fittings. Hardness testing may also be required on weld metal and heat-affected zones, not only on the base material.

Set the Applicable Standards

List the exact standard editions in the purchase order.

API Specification 6D, 25th edition, was issued in November 2021. Addendum 3 was issued on March 5, 2025.^[2]

ISO 14313:2025 covers axial, ball, check, gate, and plug valves for petroleum, natural gas, and related pipeline applications and supplements API 6D, 25th edition.^[3]

ASME B31.4-2025 covers liquid and slurry pipeline systems, including design, construction, inspection, testing, operation, and maintenance.^[4]

Other project standards may include:

• ASME B16.34 for valve pressure-temperature requirements
• ASME B16.5 or B16.47 for flanges
• ASME B16.10 for face-to-face dimensions
• ASME B16.25 for butt-weld ends
• API 6FA, API 607, or ISO 10497 for fire testing
• ISO 15848 for fugitive emissions
• ISO 15156 or another approved sour-service material standard
• Project coating and local pipeline requirements

Do not add standards that do not apply. Extra references can create conflicting requirements and unnecessary tests. The purchase order should also state which document has priority when requirements differ.

Check Fire-Test Qualification

A fire-test certificate qualifies a valve design. It does not mean every production valve is burned during factory testing.

API 6FA covers fire testing of the pressure-containing and pressure-controlling performance of API 6A and API 6D valves.^[5] API 607 covers fire testing of quarter-turn valves and valves fitted with nonmetallic seats.^[6] ISO 10497:2022 provides fire type-testing requirements for isolation valves.^[7]

Check that the qualification evidence covers the ordered:

• Valve type and ball support
• Body construction
• Seat and stem-seal design
• Size and pressure class
• Material group
• Permitted qualification extensions

Do not accept a report for a small floating valve as automatic proof for a large trunnion valve with a different body and seat design. Ask for the full report or a qualification matrix, not only the first page of a certificate.

For further comparison, see the guide to API 607 and API 6FA fire-safe testing.

Size the Actuator

The actuator must provide enough torque at every point in the valve travel under the lowest available power condition.

The valve manufacturer should provide:

• Break-to-open torque
• Running torque
• End-to-open torque
• Break-to-close torque
• End-to-close torque
• Maximum allowable stem torque
• Gearbox output limit
• Torque at minimum and maximum temperatures
• Torque at maximum pressure difference

The actuator calculation should use the selected seat and seal materials, temperature range, fluid condition, operating frequency, gearbox efficiency, stem-extension losses, and project safety factor.

For pneumatic or hydraulic actuators, check the minimum, normal, and maximum supply pressure. For electric actuators, check voltage, motor duty, starting current, enclosure, hazardous-area certificate, control signals, limit switches, and torque switches.

For gas-over-oil systems, define the pipeline-gas pressure range, filtration, hydraulic circuit, storage capacity, emergency operation, and number of operations available after loss of normal power.

A larger actuator is not always safer. Excess torque can damage the stem, gearbox, keys, or stops. The maximum actuator output must remain below the allowable torque of the valve drive train.

Closing time also matters. Closing a large liquid-pipeline valve too quickly can cause pressure surge. Use the pipeline hydraulic study to set the operating time.

See this valve torque curve guide for a practical explanation of break torque, running torque, and actuator margin.

Plan the Production Timeline

The following ranges are suitable for early planning. They are not fixed industry rules, and several activities can run at the same time.

Do not add every row to calculate the total lead time. Drawings, raw-material purchase, actuator production, procedures, and document preparation may overlap.

A common critical path is:

Technical freeze → long-lead material release → material inspection → machining → assembly → testing → NCR closure → coating → final release → packing → shipment.

The contingency percentages are buyer planning allowances, not extra time that should automatically be added to the supplier’s contract. They should be held separately and used for real risks such as material delay, inspection rescheduling, test failure, or transport disruption.

Measure the Effect of Changes

Late changes do not affect every order in the same way. The following ranges are useful for early schedule discussions but should not be treated as guaranteed delays.

These figures should not be added automatically. Some activities overlap, while a change affecting a critical-path forging or completed machining can move the final delivery date directly.

Approve the Drawings

The first document package should normally be submitted about 5 to 10 working days after kickoff for a standard order. Complex valves may require more time.

The package should include:

• General arrangement and cross-section drawings
• Valve data sheet and bill of materials
• Bore profile and seat schematic
• Flange or butt-weld-end drawing
• Stem-extension and actuator drawings
• Valve torque and actuator calculations
• Inspection and test plan
• Coating procedure
• Document register

Check the bore, face-to-face length, end connections, overall height, actuator clearance, support position, drain and vent locations, lifting points, weight, and center of gravity.

Comments from the owner, EPC contractor, pipeline designer, and inspector should be combined into one list. A normal review should ideally be completed in one or two main comment rounds. Each extra full review round may add about 3 to 7 working days.

A review period of about five working days per submission is a practical target for many projects, but the actual period should be stated in the contract.

The contract should define document status, such as:

• Approved
• Approved with comments
• Revise and resubmit
• Approved for material purchase
• Approved for manufacture

A conditional material release can shorten the schedule, but it must state which dimensions and materials are frozen and who accepts the cost of later changes.

Control Materials and Manufacturing

Before releasing material, check the grade, heat number, chemical composition, mechanical properties, heat treatment, impact results, hardness, PMI, NDE, and repair history.

The heat number must remain traceable after cutting and machining. A material-status report should show:

• Component name
• Material supplier
• Purchase date
• Expected arrival date
• Actual arrival date
• Certificate status
• Inspection status
• Release status

For standard orders, progress reports every two weeks are often enough. For critical or delayed valves, require a weekly update supported by material records, photographs, machining status, inspection reports, and test bookings.

During machining, inspect:

• Ball diameter, roundness, and finish
• Seat contact and seat-pocket dimensions
• Stem, trunnion, and bearing clearances
• Bore diameter and alignment
• Flange or weld-end dimensions
• Overall valve length

The ball and seats should be checked as one sealing system. Regrinding, lapping, recoating, or weld repair must follow an approved procedure and be followed by the required dimensional and nondestructive examination.

Before assembly, confirm that every part has been accepted. Assembly records should show the valve serial number, major heat numbers, seat and seal batches, lubricant, bolt-tightening method, seat direction, gearbox or actuator setting, and cleanliness check.

Plan the Tests

The inspection and test plan should state the activity, acceptance requirement, record, responsible party, and whether it is a hold, witness, or document-review point.

Depending on the valve design and project specification, production checks may include:

• Shell hydrostatic test
• Upstream and downstream seat tests
• Low-pressure gas seat test
• Body-cavity and cavity-relief test
• Operational and torque test
• Antistatic continuity
• Drain and vent test
• Actuator and emergency shutdown test
• Dimensional and coating inspection

Not every optional test applies to every valve. The order should state the pressure, medium, duration, valve position, test direction, leakage limit, cycle count, recording method, water quality, and drying requirement.

Specify high-pressure gas testing, low-temperature testing, fugitive-emission testing, or unusual functional testing before placing the order. These tests may need special equipment and extra time.

For a small valve batch, allow about 3 to 7 working days for pressure, functional, and associated inspection activities. This does not include time needed to repair and retest a failed valve.

See the API 6D ball valve testing guide for more detail.

Review the Factory Acceptance Test

Give the buyer and third-party inspector enough notice. A practical notification period is about 5 to 10 working days unless the contract requires a different period.

Before FAT, review the approved drawings, data sheet, material records, calibration certificates, test procedure, approved deviations, and open nonconformity reports.

Before FAT begins, about 80% to 90% of the required manufacturing records should normally be available for review. This is a useful project-control target, not a standard requirement. Waiting until FAT to collect material and inspection records creates a high risk of delayed release.

During FAT, check:

• Valve tag, serial number, nameplate, size, and pressure class
• Material and flow-direction markings
• Open and closed indication
• Drain, vent, and injection locations
• Shell and seat leakage results
• Operating torque
• Actuator travel, operating time, fail action, and signals
• Final coating condition

The test report should show the actual pressure, duration, medium, leakage result, equipment, calibration status, inspector attendance, and open items. “Passed” alone is not enough.

For a routine FAT, request the formal report within about 3 to 5 working days after testing. A failed pressure test, wrong bore, unapproved material, incorrect actuator, major coating defect, or missing traceability record should prevent final release until the issue is closed.

A practical witness checklist is available in the API 6D factory acceptance test guide.

Check the External Coating

The coating for a buried valve must match the soil, groundwater, pipeline coating, operating temperature, field-joint coating, and cathodic-protection system.

The coating procedure should state:

• Surface preparation
• Primer and finish coats
• Total dry-film thickness
• Application and curing conditions
• Holiday-test method and voltage basis
• Adhesion test and repair method
• Surfaces that must remain uncoated

Check body joints, welds, lifting lugs, support feet, drains, vents, brackets, and the base of the stem extension. Repeat the visual and holiday inspection after FAT because handling can damage the coating.

Do not use one fixed holiday-test voltage for every coating. The voltage must match the coating type, thickness, and applicable project specification.

Close the Final Documents

Define the final data book when the order is placed. It may include:

• Approved and as-built drawings
• Final data sheets and bill of materials
• Material, heat-treatment, impact, hardness, PMI, and NDE records
• Welding procedures and welder qualifications
• Pressure, functional, torque, and coating reports
• Calibration certificates
• Fire-test qualification
• Approved deviations and closed NCRs
• Inspection release note
• Packing and spare-parts lists
• Operation and maintenance manual

The API Composite List can be used to check current API Monogram licensees and registered facilities.^[8] Verify the legal company name, exact factory address, license number, product scope, and current status.

Each report should link to the relevant valve serial number. Prepare documents during production rather than after the valves are finished. A completed valve may still be unable to ship if its release records are missing.

Examples of available inspection and document support are listed on CARILO’s valve testing and documentation service page.

Pack the Valves

Before packing:

• Drain and dry all test water
• Apply an approved and compatible preservative
• Fit strong end covers
• Secure the ball in the approved shipping position
• Support the actuator without loading the stem extension
• Protect drains, vents, tubing, and injection fittings
• Mark the lifting points and center of gravity

Heavy valves should be supported through the body. Do not lift them by the handwheel, gearbox, actuator, tubing, drain line, vent line, or stem extension.

The shipping marks should show the project, purchase order, valve tag, size, weight, package dimensions, destination, lifting points, center of gravity, and storage position.

Ask for preliminary package dimensions about 2 to 4 weeks before FAT. This gives the logistics team time to check container limits, truck access, crane capacity, and oversize permits.

Plan the Freight

The logistics plan should include factory release, export packing, truck booking, port delivery, customs, vessel booking, ocean transit, destination handling, inland transport, and site unloading.

The contract should state the Incoterms® 2020 rule and named place. Incoterms® define the main delivery duties, costs, and risks shared between the buyer and seller.^[9]

Large valves may need flat-rack containers, open-top containers, breakbulk shipment, road permits, route surveys, and special cranes. Confirm packed dimensions before FAT because a small increase in actuator height can change the shipping method and cost.

For standard ocean freight, consider adding about one to two weeks of project contingency beyond the carrier’s quoted transit time. Oversize cargo, transshipment, port congestion, or difficult customs clearance may require two to four weeks or more.

On arrival, check the package before the carrier’s claim period expires. Record coating damage, water entry, corrosion, missing parts, displaced supports, bent tubing, and damaged controls.

Prevent Common Delays

For a routine order, request a detailed progress report every two weeks. For critical or delayed valves, use weekly reporting. A critical-path delay of more than five working days should trigger a written recovery plan.

If a critical activity is more than 10 working days late, the supplier should recalculate the final forecast date instead of continuing to report the original delivery date.

A recovery plan should show:

• Delayed activity and root cause
• Original and revised dates
• Effect on the critical path
• Extra shifts or production resources
• Activities that can run in parallel
• Buyer decisions required
• Updated factory-release date

Do not recover schedule by removing required tests, using unapproved materials, skipping traceability, shortening required holding times, using expired seals, reducing coating cure time, or shipping valves with open technical problems.

Order Checklist

• Quantity, size, pressure class, and required delivery date
• Design pressure, temperature, and maximum closing pressure difference
• Fluid composition, contaminants, and sour-service conditions
• Minimum bore and pigging requirements
• Body construction and end connections
• Body, ball, stem, seat, and seal materials
• Seat arrangement, DBB or DIB function, and cavity relief
• Fire-test and fugitive-emission requirements
• Stem extension, drains, vents, and sealant fittings
• Actuator type, supply conditions, operating time, and fail position
• Coating and cathodic-protection interface
• Applicable standards and editions
• Inspection, testing, third-party witness, and document requirements
• Spare parts, special tools, preservation, and packing
• Contractual Day 0, factory-release date, Incoterms® rule, and site date

Final Advice

Use 16 to 24 weeks only as an early factory estimate for a clearly specified order of roughly 1 to 10 valves using common materials and standard testing. Allow 24 to 40 weeks or longer for large forgings, high pressure classes, sour service, weld overlay, complex actuators, or project-specific tests. Keep drawing reviews to one or two main rounds, require weekly reporting when a critical activity is more than five working days late, and have 80% to 90% of manufacturing records ready before FAT. Confirm package dimensions two to four weeks before FAT and book special freight four to eight weeks before pickup. These controls reduce late material changes, failed actuator sizing, incomplete documents, and missed site dates.