API 6A Manual Orifice Plate Throttle Valve
Nominal Sizes: 2-1/16″, 3-1/8″, 4-1/16″ (Equivalent Max Orifice Sizes: 1″ to 3″)
Working Pressure Ratings: 2,000 PSI to 15,000 PSI (13.8 MPa to 103.5 MPa)
Product Specification Levels (PSL): PSL 1, PSL 2, PSL 3, PSL 3G
Performance Requirement Levels (PR): PR 1, PR 2
Material Classes: AA, BB, CC, DD, EE, FF, HH (Fully compliant with NACE MR0175 / ISO 15156)
Temperature Ratings: K, L, P, R, S, T, U, V (-46°C to +121°C)
End Connections: API 6A Flanged, Clamp Hub, or Hammer Union
API 6A Manual Orifice Plate Throttle Valve
Product Definition & Safety Mission:
Serving as a specialized pressure and flow regulation system for high-sand, high-differential pressure wellheads and choke manifolds, the JH Manual Orifice Plate Throttle Valve ensures long-term system safety. Utilizing dual precision-lapped tungsten carbide or ceramic orifice plates, it confines high-velocity fluid jets to the orifice center, preserving valve body integrity under severe cavitation and frac flowback.
JH-Valve Orifice Throttle Valve Technology Core:
- Dual Carbide/Ceramic Disc Defense: Core choking trim built from precision-lapped solid carbide or ceramic discs resists severe sand erosion and cavitation.
- Shearing Surface Flow Regulation: Rotating and stationary discs maintain intimate face contact, preventing direct jet impingement on sealing surfaces.
- PSL 3G & PR2 Certified Integrity: Manufactured to API 6A PSL 3/3G standards and PR2 validated, ensuring reliable choking up to 15,000 PSI.
- 100% NACE MR0175 Compliant: High-strength alloy construction ensures total immunity to H2S/CO2 Sulfide Stress Cracking (SSC) in sour services.
- Erosion-Resistant Choking
- Safety & Maintenance
- PSL 3G & PR2
Engineered for severe high-sand flowback, sandy slurry production, and high-differential pressure throttling where conventional chokes fail rapidly.
Core Features:
▌ Dual Orifice Plate Mechanism → Features a pair of precision-lapped, high-hardness Tungsten Carbide or ceramic discs | Rotating the upper disc adjusts the overlapping area, keeping high-velocity fluid jets away from sealing surfaces to maximize wear life
▌ Calibrated Visual Indicator → Top-mounted scale plate with clear graduations | Provides exact real-time indication of relative plate position and equivalent choke orifice size for precise manual adjustment
▌ Anti-Cavitation Architecture → Energy dissipation centered within the orifice bore | Protects critical sealing interfaces from cavitation damage and prevents sand particles or debris from jamming the trim
Provides multi-layered mechanical safety features and simplified field maintenance for high-pressure choke & kill manifolds.
Core Features:
▌ Anti-Blowout Stem & Back-Seat → Integrated anti-blowout stem design paired with mechanical back-seating | Guarantees stem retention under extreme pressure and enables safe online packing inspection under pressure
▌ Low Torque Manual Drive → Precision stem threads combined with heavy-duty thrust bearings | Ensures smooth handwheel rotation and effortless adjustment even under differential pressures up to 15,000 PSI
▌ Fast Inline Trim Servicing → Modular bonnet and disc cartridge construction | Allows field personnel to inspect and replace the orifice plates quickly without removing the valve body from the line
Fully certified to meet the most stringent global standards for high-pressure surface wellhead and manifold systems.
Core Features:
▌ PSL 3 / PSL 3G Quality Standards → 100% volumetric NDE on body forgings and high-pressure gas testing | Ensures complete structural integrity for high-consequence onshore and offshore pressure control
▌ PR2 Performance Verification → Validated under rigorous API 6A PR2 dynamic pressure and thermal cycling | Maintains flawless seal integrity and smooth operation from -46°C to +121°C under high pressure differentials
▌ 100% NACE MR0175 Compliance → Forged construction across API Material Classes AA–HH | Delivers complete resistance to Sulfide Stress Cracking (SSC) in aggressive sour service (H2S/CO2) environments
Core Design & Advantages
- Hard-Faced Dual Orifice Trim → Stationary and rotating discs precision-lapped from solid Tungsten Carbide or engineering ceramics (Hardness ≥ 88 HRA) | Delivers supreme resistance against heavy sand erosion, high-velocity jetting, and cavitation
- Surface-Contact Shearing Flow Regulation → Discs maintain continuous face-to-face contact while adjusting overlapping orifice geometry | Protects primary sealing interfaces from direct fluid jet impingement for linear and predictable flow control
- Strict PSL 3G & PR2 Level Integrity → Built to rigorous API 6A PSL 3 / PSL 3G standards and validated by PR2 performance cycling | Guarantees reliable operation and absolute seal integrity up to 15,000 PSI and -46°C to +121°C
- Anti-Blowout Stem with Back-Seat Sealing → Integrated anti-blowout stem mechanism paired with mechanical back-seating | Prevents stem ejection under high pressure while permitting safe online packing inspection under pressure
- 100% Severe Sour Service Readiness → Fully compliant with NACE MR0175 / ISO 15156 standards (API Material Classes AA–HH) | Offers total protection against Sulfide Stress Cracking (SSC) in aggressive H2S/CO2 environments
- Low Operating Torque & Inline Maintenance → High-precision stem threads with heavy-duty thrust bearings; modular disc cartridge | Ensures effortless handwheel operation under extreme differential pressure and allows rapid disc replacement without removing the body from the line
API-API 6A Manual Orifice Plate Throttle Valve
The JH Manual Orifice Plate Throttle Valve utilizes two overlapping, high-precision machined tungsten carbide discs—one fixed in the valve body and one rotating driven by the stem. As the handwheel rotates the top disc, the relative alignment of the orifice holes changes, enabling precise, step-less control of flow rate and pressure drawdown. This design ensures that fluid throttling occurs purely across the tungsten carbide discs, protecting the valve body from internal fluid erosion.
Unlike needle-type chokes where fluid rushes past a narrow stem taper, orifice plate choke valves regulate flow through parallel face-to-face tungsten carbide discs. This structure offers superior wear resistance against severe sand erosion and mud slurry flow, lower operating torque under extreme differential pressure, and complete protection of sealing surfaces when the valve is fully shut, significantly extending valve service life.
PSL 3G represents the highest quality control tier under API 6A for gas-tight wellhead equipment, mandating rigorous high-pressure gas (Nitrogen) shell and seat testing beyond standard hydrostatic tests. JH-Valve holds official API 6A authorization with PSL 3G capability explicitly scope-covered on our official API certificate. Every PSL 3G valve undergoes in-house gas testing to guarantee zero-leakage gas containment in severe high-pressure gas wells.
PR2 (Performance Requirement Level 2) validates that a valve maintains bubble-tight sealing and smooth operation through dynamic temperature cycles (-46°C to +121°C) under full working pressure (up to 20,000 PSI). JH-Valve’s API 6A qualification scope officially includes PR2 performance validation, backed by certified third-party dynamic cycling test reports to ensure uncompromising reliability under extreme field fluctuations.
Every JH-Valve specified for sour service uses forged body materials and internal trims compliant with NACE MR0175 material limits. We strictly control heat treatment processes (such as double tempering) to maintain material hardness below HRC 22, eliminating the risk of Sulfide Stress Cracking (SSC) and Hydrogen-Induced Cracking (HIC) in high H₂S/CO₂ sour oil and gas environments.
JH-Valve offers full pressure ratings ranging from 2,000 PSI to 20,000 PSI (13.8 MPa to 138.0 MPa) and sizes from 2-1/16″ to 7-1/16″. End connections can be customized to API 6A 6B/6BX flanged ends, API 6A studded connections, or high-pressure hammer union ends (e.g., Fig 1502/2202) according to project specifications.
Yes. JH-Valve wellhead valves, including our manual orifice plate throttle valves and choke valves, feature a top-entry architecture. Field technicians can unbolt the top bonnet assembly and extract internal tungsten carbide orifice discs or stem assemblies for fast inspection and replacement without disconnecting the valve body from the manifold line, minimizing field downtime.