I. Product Definition and Function
The choke manifold control panel is the core control device on the hydraulic choke manifold. It is mainly used to remotely control the opening and closing of the hydraulic choke valve and display the standpipe pressure, casing pressure, and the open and closed position of the hydraulic choke valve on the control panel panel. Its main function is to control the bottom hole pressure by adjusting the opening degree of the choke valve, maintaining the balance between the bottom hole pressure and the formation pressure. It is a key equipment necessary for successfully controlling well kick, blowout, and implementing pressure control technology for oil and gas wells.
II. Technical Standards System
The main technical standards implemented by the choke manifold controlpanel include:
API Spec 16C: Specification for Throttle and Kill Manifold Systems, an international general standard
SY/T 5323: Specification for Throttle and Kill Equipment for Drilling and Production in Petroleum and Natural Gas Industry, a Chinese industry standard
SY/T 5053.1-2000: Test Specification for choke control panel.
III. Core Working Principle
The choke manifold control panel adopts the gas-liquid balance principle, integrating pneumatic and hydraulic functions. It converts the external air source pressure into hydraulic energy to control the opening or closing of the hydraulic throttle valve. The specific working process is as follows:
1. Pneumatic Hydraulic Pump Working Process
After the air source enters the control panel, it is divided into two paths: one path passes through the pressure reducing valve to reduce the air source pressure to 0.35 MPa, providing it to the position transducer and pressure transducer; the other path enters the pneumatic pump to drive the piston to move.
The pneumatic pump raises the oil pressure to 3.0 - 3.1 MPa, and the high-pressure hydraulic oil is stored in the accumulator.
When the three-position four-way directional valve is operated, the high-pressure control fluid from the accumulator is realized through the manual directional valve on the control panel panel to remotely open and close the manifold hydraulic valve.
2. Automatic Control Mechanism
The pneumatic hydraulic pump is equipped with an automatic start and stop control device.
When the system oil pressure drops to the set value of the pneumatic pump's start pressure, the pneumatic pump automatically resumes operation to replenish the system pressure.
When the pressure reaches the stop pump set value, the pneumatic pump automatically stops working.
IV. Main Technical Parameters
Parameter Category Technical Indicators Remarks
System Pressure Nominal Pressure: 7 - 21 MPa Available in different pressure levels
Working Pressure 3 - 8 MPa Adjustable range
Air Source Pressure 0.65 - 1.00 MPa Required input air source
Environmental Temperature -29℃ ~ +80℃ Adaptable to extreme environments
Cylinder Volume: 6.3 - 16 L, Working Pressure: 10 - 21 MPa Pre-filled nitrogen pressure: 1.00 ± 0.1 MPa
Hydraulic Oil Specification 10# Aviation Hydraulic Oil or Anti-Cold Wear Hydraulic Oil Select 32HM above 0℃, 32HV below 0℃
Pressure Transmitter Range: 0 - 35 MPa, Connection Form: 2" FIG1502M Pneumatic or Electronic
Valve Position Transmitter Range: 0 - 47 mm Displays the opening degree of the throttle valve
Pump Stroke Counter Main Line: 50 m, Branch Line: 25 m per unit, Total 3 units Displays the strokes and frequency of the mud pump
V. System Composition and Structure
The choke manifold control panel is mainly composed of the following components:
1. Power System
Pneumatic Hydraulic Pump: Uses compressed air as the power source, with the air source pressure proportional to the output liquid pressure
Manual Pump: Backup power source, ensuring normal system operation in the event of a loss of air source
Electric Gear Pump: Some models adopt an electric form, with a power of 1.5 kW, voltage 380V ± 19%
2. Energy Storage System
Cylinder: Volume: 6.3 - 16 L, Pre-filled nitrogen pressure: 1.00 ± 0.1 MPa, Stores high-pressure control fluid
Oil Tank: Volume: 670 L, Stores hydraulic oil
3. Control and Display System
Three-Position Four-Port Manual Directional Valve: Controls the opening and closing of the hydraulic throttle valve
Speed Control Valve: Controls the opening and closing speed of the hydraulic throttle valve
Pressure Transmitter: Displays standpipe pressure and casing pressure
Valve Position Transmitter: Displays the valve position opening degree of the hydraulic throttle valve
Pump Stroke Counter: Displays the strokes and frequency of the mud pump
4. Safety Protection System
Overflow Valve: Automatically opens and releases pressure when the system oil pressure exceeds the set value
Safety Valve: Set pressure range 2.6 - 3.0 MPa, Ensures system safety
Pressure Relief Valve: Manual pressure relief in emergency situations
VI. Product Types and Features
1. Pneumatic Throttle Manifold control panel
Features: Powered by compressed air, with excellent explosion-proof performance. It has high requirements for the cleanliness, moisture content, and temperature of the air source.
Applicable scenarios: Routine drilling operations, in environments with sufficient air supply.
2. Electric Throttle Manifold control panel
Features: Powered by pure electricity, safe and reliable, quick pressure application, no need for air source, simple and convenient operation.
Technical parameters: Rated output oil pressure 4MPa (maximum 6MPa), power supply voltage 380V ± 19%, motor power 1.5KW
Advantages: Uses full electronic digital display, the electric pump has automatic start-stop control, fast response, high precision
3. Electronic Throttle Manifold control panel
Features: Replaces traditional pressure gauges and pneumatic sensors with electronic digital meters. The electronic pressure sensor has reliable performance and high sensitivity.
Innovation point: Replaces conventional pneumatic valve position transmitters with high-precision electronic displacement sensors, eliminating the need for air source at the user's site, high precision, and easy installation
VII. On-site Configuration and Operation Requirements
1. Installation Location
The throttle manifold control panel is placed on the drilling platform on the side close to the riser pipe, or in the BOP room, for easy operation and observation.
2. Standby State Requirements
Air source pressure: 0.65~1.00MPa
Valve position opening: 3/8~1/2 (converted proportionally by the digital display)
Valve position transmitters and pressure transmitters of the pneumatic throttle manifold control panel: 0.35MPa
Working pressure of the air pump when stopped: 3.00~3.10MPa
Pre-charged nitrogen pressure of the accumulator: 1.00±0.1MPa
Pressure setting value of the relief valve: 4.2MPa
3. Daily Inspection Contents
Whether the valves are flexible in operation (throttle valve in half-open state)
Sealing conditions of the liquid and gas circuits (hydraulic throttle valve, valve position transmitters, pressure transmitters)
Working status of detection instruments such as pressure gauges
Clear visual identification
Inspection of the elbow of the blowout line
VIII. Industry Development Trends
1. Intelligent Upgrades
Digital Twin Junction Box: The penetration rate has rapidly increased from 12% in 2022 to 28% in 2024. The intelligent diagnostic system reduces downtime due to faults by 45%.
Remote Monitoring: Combined with information technologies such as the Internet of Things and cloud computing, it enables remote monitoring and intelligent maintenance of equipment.
Automated Control: Equipped with hydraulic control paneles, it supports local/remote control, with control accuracy reaching 0.1%.
2. Breakthroughs in High-Sulfur Resistance Technology
HH-Class Automatic Throttle Junction Box: It can operate stably in acidic environments with high sulfur content (20% hydrogen sulfide) and moderate to high corrosion (15% carbon dioxide).
Material Upgrade: The overall material strictly follows the HH-level requirements of API 6A, with strong corrosion resistance.
3. Environmental Protection and Energy Saving Requirements
Green and Environmentally Friendly: Improving energy efficiency and reducing environmental impact have become important considerations in product design.
VOCs Control: The Ministry of Ecology and Environment requires that all organic volatile matter junction boxes be sealed and renovated by 2026.
Energy-saving Design: Adopting energy-efficient design to reduce energy loss during fluid transportation.
4. Market Prospects
Market Size: The market size of throttling junction boxes in China has grown from 3 billion yuan in 2017 to 6.5 billion yuan in 2022, with an average annual compound growth rate of approximately 10%.
Export Growth: After the RCEP came into effect, the tariff rate for Chinese junction boxes for Southeast Asian refining and petrochemical projects was reduced from 8% to 2.5%, and the export scale is expected to increase to 5.2 billion yuan in 2025.
Application Areas: Deep-sea oil and gas development, high-sulfur oil and gas fields, and intelligent oilfield construction, among other emerging fields, continue to show growing demand.
IX. Quality Certification and Safety Requirements
The choke manifold control panel must obtain the following certifications:
API Spec Q1: Quality Management System Certification
API 16C: Throttle and Well Control System Certification
ISO9001: Quality Management System Certification
ISO14001: Environmental Management System Certification
ISO45001: Occupational Health and Safety Management System Certification
HSE: Health, Safety and Environment Management System Certification
Explosion-proof rating: ExdⅡBT4, Protection rating: IP56
X. Maintenance and Scrap Standards
1. Daily Maintenance
Regularly check the hydraulic oil level and replenish or replace it in time
Check the air source pressure and maintain it at 0.65 - 0.85 MPa
Check the nitrogen pressure of the accumulator and keep it at 1.00 ± 0.1 MPa
Regularly clean the oil tank and filters
2. Scrap Evaluation
Safety Status Level: Divided into 2 levels. The detection cycle for level 1 is 2 years, and level 2 should be stopped from use
Scrap Criteria: Overpressure use, pipe body deformation or leakage, wall thickness reduction, abnormal sound emission detection, etc.
Scrap Principles: Scrap using the component replacement principle. It is strictly prohibited to use valve components produced by enterprises without qualifications
The choke manifold control panel is an important component of well control equipment. Its technical level and reliability directly affect the safety and efficiency of drilling operations. With the continuous development of intelligent, high-sulfur resistance, environmental protection, and energy-saving technologies, the choke manifold control panel will play a more important role in oil and gas exploration and development.