Christmas Tree (X-Tree)

Key Features

Full Pressure & Scenario Coverage

Available in full pressure ratings from 2MPa (300psi) to 105MPa (15000psi) and nominal bore sizes from 2-1/16" to 11-1/16" to match different well conditions and production capacity requirements. Standard configurations support both vertical and deviated well operations, with optional specialized kits for HTHP wells (max 177℃/350℉ operating temperature), sour gas wells (H₂S partial pressure up to 1.5MPa, CO₂ partial pressure up to 10MPa) and high-viscosity heavy oil wells. Both above-ground conventional and optional subsea (API 17D compliant) Christmas Tree configurations are available to cover onshore and offshore operation scenarios.

Full Compliance with Global Regulatory Standards

All core components pass 100% ultrasonic testing (UT) and 1.5x rated working pressure hydrostatic test before shipment, with zero defect delivery requirements. The whole unit is certified with ISO 9001 quality management system, and we provide full regional certification support for target markets:

North America: ASME U-stamp certification, OSHA-compliant safety guard design, API 6A monogram certification

CIS/EU: EAC (TR CU) certification, GOST-R certification, low-temperature (-40℃) impact test report for arctic operation

Middle East: SASO/GSO certification, Saudi Aramco/ADNOC supplier qualification support, high-temperature anti-sand design certification

South Asia: BIS certification, BIS product testing report for Indian market import clearance.

High Safety & Reliability Design

Dual-redundant master valve design (standard for pressure ratings above 5000psi) ensures reliable well control in case of single valve failure; all valve seals adopt a dual metal-seal + polymer seal structure, with zero external leakage rate under 1.1x rated working pressure. The unit is equipped with standardized pressure monitoring ports, production logging ports and emergency chemical injection ports, with optional integrated emergency shutdown (ESD) system that supports both local manual shutdown and remote wireless shutdown. Optional H₂S online monitoring module and corrosion-resistant alloy (Monel/Inconel) material are available for sour gas wells to prevent sulfide stress cracking.

Fast Installation & Low Lifecycle Cost

Modular design supports flange connection installation on-site without complex welding, with standard installation time of 4~8 hours, 60% faster than traditional welded wellhead devices. All valves adopt a modular cartridge design, so on-site maintenance only requires replacing the valve core or seal without replacing the entire valve, reducing maintenance cost by 40%. The surface adopts hot-dip galvanized + fluorocarbon anti-corrosion coating, with a designed service life of 20+ years under standard operating conditions, and all wearing parts are compatible with global mainstream Christmas Tree brands to reduce spare part procurement costs.

Full After-Sales Support

100% factory hydrostatic test and function test before shipment, with third-party inspection (SGS/BV) available upon request

Free on-site installation guidance, commissioning and 2~3 days of operator training, with multi-language training materials (English/Russian/Arabic/Spanish) available

24-month warranty for the whole unit, 36-month warranty for core valves and seals

7*24 hour remote technical support, 1-hour response for urgent fault diagnosis; local service teams available for core markets with on-site support within 48 hours for urgent failures

Global spare parts warehouses in Houston, Dubai and Moscow, with common wearing parts available for global air shipping within 3~5 days, ensuring long-term stable supply matching the unit's 20+ year designed service life.

Product Structure

1. Tubing Head & Lower Wellhead Connection Assembly

As the load-bearing and sealing interface between the Christmas Tree and the wellbore, this assembly ensures reliable suspension of downhole tubing and wellbore isolation:

Tubing hanger: Made of high-strength alloy steel (optional low-temperature steel, duplex stainless steel, Monel/Inconel for sour gas service), with standardized bore sizes matching tubing OD (2-3/8" ~ 7" available), with integrated sealing grooves to match the tubing head sealing assembly. It bears the full weight of the upper Christmas Tree and downhole tubing string, with a safety factor of ≥2.5 times the maximum tubing load.

Tubing head sealing assembly: Dual-seal structure (metal-to-metal seal + polymer seal) to achieve zero external leakage under 1.1× rated working pressure, with optional H₂S-resistant sealing material for sour gas wells.

Casing head connection flange: Standardized API 6A flange connection (optional hub connection, hammer union for fast installation), with pressure test ports for annulus pressure testing, compatible with standard casing head spools.

Arctic low-temperature kit (optional): Low-temperature resistant sealing material and steel (impact toughness ≥40J at -40℃) are available for CIS and high-latitude operation scenarios, avoiding embrittlement failure.

2. Core Valve Assembly (Core Control Module)

The valve assembly is the core flow control component of the Christmas Tree, with configurable valve combinations to match different operation requirements:

Master Valve Assembly: Installed between the tubing head and wing valve assembly, used for complete wellbore isolation in emergency. Standard configuration for pressure ratings ≤10000psi is single production master valve + single tubing master valve; for pressure ratings ≥15000psi and HTHP wells, a redundant dual master valve design is standard to ensure reliable well control in case of single valve failure. All valves adopt a full-bore design to reduce flow resistance, with optional hydraulic actuator or manual handwheel operation.

Wing Valve Assembly: Usually configured with dual wing valves (production wing valve + injection/service wing valve), used for daily production flow control, well killing, chemical injection and workover operation flow control. Full-bore design is optional for workover operation requirements, with standard throttling design for production operation to reduce erosion.

Choke Assembly (optional): Integrated adjustable choke or fixed choke, with rated pressure matched to the Christmas Tree's working pressure, used for production pressure control and flow rate adjustment. The choke trim is made of tungsten carbide alloy, with a rated service life of ≥5 years under sand-carrying production conditions.

All valves are equipped with a dual metal-to-metal seal + polymer seal structure, with zero external leakage rate under 1.1× rated working pressure, and each valve is equipped with an individual pressure test port for on-site function testing.

3. Vertical Spool & Manifold Assembly

The vertical spool is the connecting body between the lower tubing head and the upper valve assembly, integrating multiple auxiliary function interfaces:

Main spool body: Made of forged high-strength carbon steel / stainless steel, with rated working pressure matched to the overall Christmas Tree pressure rating, with optional corrosion-resistant alloy material for sour gas service.

Auxiliary interface ports: Standardized 1/2"~1" API pressure monitoring ports (for wellhead pressure, tubing pressure, annulus pressure monitoring), chemical injection ports (optional dual ports for continuous chemical injection), and production logging ports for downhole production logging operation.

Top outlet flange: Standardized API 6A flange connection, matching the downstream production pipeline or manifold connection specifications.

Anti-corrosion treatment: The outer surface adopts hot-dip galvanizing + fluorocarbon coating as standard, with optional three-layer PE anti-corrosion coating for high-humidity and high-salt spray environments such as offshore wells.

4. Top Control & Safety Monitoring Module

Integrated at the top of the Christmas Tree or the valve group, this module realizes operation control and real-time status monitoring:

Operation execution components: Manual handwheels for manual valve operation, optional hydraulic actuator (for ESD system), optional motor actuators for remote automatic control.

Monitoring sensors: Integrated pressure sensors (for tubing pressure, annulus pressure, choke outlet pressure monitoring), temperature sensors, optional H₂S/CO₂ online monitoring sensors, with 4~20mA standard signal output compatible with field RTU/SCADA systems.

Safety components: Optional emergency shutdown (ESD) system, supporting local manual shutdown and remote wireless shutdown, with response time ≤1s; optional safety clamp for wellhead pipeline connection to prevent pipeline fall-off.

Control interface: Standardized hydraulic control pipeline interface (for hydraulic actuated valves), explosion-proof electrical control interface for hazardous areas, compatible with mainstream oilfield control systems.

5. Optional Special Configuration Modules

Customizable modules for specific operation scenarios:

Sour gas anti-corrosion kit: All wetted parts adopt Monel/Inconel alloy or duplex stainless steel material, with H₂S-resistant sealing material, anti-sulfide stress cracking (SSC) heat treatment, suitable for high-H₂S gas wells.

Arctic low-temperature kit: Low-temperature resistant steel, low-temperature flexible sealing material, low-temperature grease, suitable for -40℃ ambient temperature operation, with low-temperature impact test report available.

High-temperature kit: High-temperature resistant sealing material, upgraded valve stem packing, suitable for operating temperatures up to 177℃ (350℉) HTHP wells.

Subsea Christmas Tree configuration: Compliant with API 17D standards, with subsea connector, subsea control module (SCM), corrosion-resistant alloy material and deep-sea anti-collision design, suitable for offshore platform and subsea well operation.

Compatible Brands

CNOOC, SPM, Jereh

FAQ

Q1: Can the Christmas Tree be customized to match our specific well conditions and operation requirements?

Yes, full customization is supported. You can select rated working pressure (2MPa~105MPa / 300psi~15000psi), nominal bore size (2-1/16"~11-1/16"), valve configuration, material grade and special functional modules based on your well type (conventional oil/gas well, shale well, HTHP well, sour gas well, offshore well). We provide free customized technical proposals and formal quotations within 3 working days upon receipt of your well parameters (formation pressure, temperature, H₂S/CO₂ content, well deviation angle, etc.).

Q2: What special configurations are available for extreme well conditions?

We offer full scenario-specific kits to match your operation environment:

Sour gas well kit: All wetted parts adopt NACE MR0175-compliant corrosion-resistant alloy (Monel/Inconel/duplex stainless steel), with H₂S-resistant sealing material and anti-sulfide stress cracking heat treatment, suitable for wells with H₂S partial pressure up to 1.5MPa

Arctic low-temperature kit: Low-temperature steel (impact toughness ≥40J at -40℃) and low-temperature flexible seals, suitable for -40℃ ambient temperature operation in CIS and high-latitude regions

High-temperature HTHP well kit: High-temperature resistant valve stem packing and seals, suitable for operating temperatures up to 177℃ (350℉)

Offshore/subsea kit: Compliant with API 17D standards, with subsea connectors, corrosion-resistant alloy material and deep-sea anti-collision design, suitable for shallow/ deepwater platform and subsea well operation.

Q3: Can the Christmas Tree be adapted to our existing wellhead equipment?

Yes, all our products adopt standardized API 6A interface design, supporting multiple connection types: flange connection, hub connection and hammer union, which can be matched with mainstream wellhead equipment in the global market. If you have special interface requirements, we can provide customized interface design to ensure perfect fit with your existing wellhead system.

Q4: What valve configurations are available? Can you add special functional modules?

Standard valve configurations include:

Single master valve + dual wing valves (for pressure ratings ≤10000psi, general production wells)

Dual master valves + dual wing valves (for pressure ratings ≥15000psi and HTHP wells, with redundant well control function)

Optional functional modules: adjustable choke, integrated ESD (emergency shutdown) system, H₂S online monitoring module, intelligent flow metering module, chemical injection port group, etc.

Q5: What does your quotation include? Do you support different trade terms?

We support all mainstream trade terms (FOB, CIF, DAP, DDU, EXW) as required. The standard FOB quotation includes: complete Christmas Tree with standard configuration, 100% factory hydrostatic test and function test fees, export customs declaration fees and standard spare parts kit. It does not include international freight, insurance, import tariffs, destination port charges and local transportation fees. We can provide a detailed quotation breakdown for your target trade term upon request. There is no minimum order quantity (MOQ) for standard configuration products, and small trial orders are welcome.

Q6: What is the warranty period? What after-sales support is provided?

Standard warranty terms:

Whole unit: 12 months (or 2000 operating hours, whichever comes first) from the date of commissioning at your site

Core components (valves, seals, sensors): 24~36 months warranty

After-sales support includes:

7*24 hour remote technical consultation, 2-hour response for fault diagnosis

Regular wearing parts (valve seals, filters, gaskets, etc.) available for global air shipping within 3~5 days

On-site service: our local service teams can arrive within 48 hours for core markets (North America, CIS, Middle East, South Asia) for urgent failure repair

Annual free on-site inspection service is available for cooperative clients

Q7: How to obtain spare parts after the warranty period? Is the supply chain stable?

We have global spare parts warehouses in Houston (USA), Dubai (UAE) and Moscow (Russia), with common wearing parts in stock. Spare parts orders can be shipped worldwide within 3~7 days. Non-standard parts have a maximum production cycle of 30 days. We will provide each client with a dedicated spare parts manual with clear part numbers, prices and inventory status to ensure 20+ year stable supply matching the product's designed service life.

How It Works

1. Basic Flow Control & Fluid Dynamics Principle

The Christmas tree operates based on fluid mechanics principles: oil, gas and water fluids flow from the reservoir into the wellbore under formation pressure, enter the Christmas tree via the tubing hanger and tubing spool, then flow through internal passages controlled by valve assemblies to the production pipeline 911. By adjusting the opening degree of the main control valve, wing valve and choke, the tree regulates the flow rate and pressure of produced fluids to ensure stable and safe production.

Sealing & Isolation: The dual metal-to-metal + elastomer seal structure at the tubing hanger and valve interfaces achieves zero external leakage under 1.1× rated working pressure, isolating the wellbore from the external environment 78.

Pressure Regulation: The integrated choke (adjustable or fixed) produces throttling effect to control wellhead pressure and production rate, maintaining production within design parameters 8.

Anti-backflow: Check valves (one-way valves) installed between wing valves and outlets automatically close when wellbore pressure drops below pipeline pressure, preventing formation fluid backflow 9.

2. Core Valve Assembly Operation Logic

The valve assembly is the core control module, working through coordinated opening/closing of different valves to achieve multi-functional operations:

2.1 Standard Valve Configuration & Operation States

Master Valve Assembly: Installed between the tubing spool and wing valve assembly. The master valve (or dual redundant master valves for HPHT/sour gas wells) fully opens during normal production to allow unimpeded fluid flow from the tubing to the upper spool. In emergency, it closes to achieve total wellbore isolation 78.

Wing Valve Assembly: Typically consists of a production wing valve (controlling flow to the production pipeline) and a service/injection wing valve (for well killing, chemical injection, fracturing or workover). Normal production requires opening the production wing valve and closing the service wing valve; when the production wing valve is closed and the service wing valve is opened, the well can undergo well killing, injection or flushing operations 3.

Choke Assembly (Optional): The adjustable choke trim (typically tungsten carbide alloy) adjusts the flow passage area by rotating the stem, precisely controlling production pressure and flow rate. The fixed choke uses different orifice inserts to change flow capacity 8.

2.2 Typical Operation Mode Valve States

Taking a common single-master + dual-wing Christmas tree as an example, the valve operation logic for common modes is as follows 3:

Normal Production: Open master valve + production wing valve; close service wing valve, choke valve and flushing valves. Formation fluid flows from tubing → master valve → production wing valve → production pipeline.

Forward Water Injection: Close master valve + service wing valve + flushing valves; open production wing valve and choke. Injection fluid enters the well via production wing valve → master valve → tubing.

Reverse Water Injection: Close master valve + production wing valve + flushing valves; open service wing valve and choke. Injection fluid enters the well via service wing valve → casing annulus.

Forward Well Flushing (Circulation): Close production wing valve + master valve; open master valve flush valve, service wing valve and connected flushing line. Flushing fluid flows from casing annulus → master valve → service wing valve → flushing line.

Reverse Well Flushing: Valve states same as forward flushing, but fluid flows from flushing line → master valve → casing annulus.