NOV SPK-51037879-3 Spares Kit for CH2 Choke Valves

NOV SPK-51037879-3 Spares Kit for CH2 Choke Valves

The NOV SPK-51037879-3 Spares Kit is a heavy duty field level overhaul kit developed by National Oilwell Varco for the repair and refurbishment of CH2 Adjustable Choke Valves . The kit is for 2-inch body configurations with a 2-inch trim layout, and contains mission-critical components including the replacement stem, seat and high-integrity elastomeric/thermoplastic seals required to maintain pressure boundaries under extreme drilling and production environments.

Model Details

• Brand: NOV (National Oilwell Varco)
• Manufacturer Part Number (MPN): SPK-51037879-3
• Associated Component Model: CH2 Series (Needle & Seat Design)
• System Designation: CH2 PEX-EE 1.5-3 T3 Energy
• Primary Cross-Reference Numbers: 20371141, 20384665
• Specification Matrix: PX EE1 5 PSL-3

Technical Details: NOV SPK-51037879-3 Spares Kit

Key Features

1. Erosion-Resistant Tungsten Carbide Trim: The stem and seat geometry feature heavy-duty tungsten carbide overlays engineered to resist high-velocity particle impingement and cavitation during severe flow-throttling operations.
2. Full API 6A PSL-3 Rating: Certified to meet exact structural and non-destructive examination (NDE) protocols required for high-risk offshore pressure containing environments.
3. Universal CH2 Compatibility: Fits legacy Best B-H2 adjustable chokes along with modern NOV CH2 manual valve variants configured with aluminum position scales.
4. Complete Pressure Barrier Overhaul: Consolidates all critical wear interfaces—including dynamic stem packings and static metallic/elastomeric bonnet seals—into a single managed part number.

System Compatibility

The SPK-51037879-3 spares kit is precision-matched for the following drilling and production equipment models:

• Choke Assemblies: NOV CH2 and CH2M Adjustable Manual Choke Valves (2″ Body / 2″ Trim layout).
• Legacy Equivalents: Best B-H2 needle-and-seat configuration adjustable chokes.
• Manifold Systems: High-pressure drilling choke manifolds, kill manifolds, and well testing surface headers rated from 3K up to 15K working pressure.

Applications

1. Offshore Drilling Manifolds: Routine and emergency pressure management within rig choke-and-kill line configurations.
2. Managed Pressure Drilling (MPD): Providing reliable sealing and precise flow control adjustments during active backpressure operations.
3. High-Pressure Well Testing: Isolation and severe-throttling deployment on portable surface production test trees dealing with unexpected sand and proppant returns.
4. Production Christmas Trees: Regular scheduled intervention maintenance on inline production headers facing sour crude/gas vectors.

Rebuild Calibration Protocol

When installing the replacement stem and seat from this kit, never rely on external optical alignment alone. Always rotate the handwheel fully clockwise to the complete mechanical closed position. Loosen the set screw on the aluminum calibration sleeve, align the sleeve indicator line precisely to the “0” index graduation, and lock it down. This prevents premature seat deformation or excessive internal bypass under full differential pressure.

Dynamic Packing Integrity

During dynamic stem packing installation, always inspect the bonnet cavity bore for micro-pitting or scoring caused by past fluid bypass. Even a minor 0.05 mm surface irregularity will quickly shave the new packing rings under high cycle operations. Always use a lint-free swab to apply a thin layer of specialized fluorosilicone or PTFE lubricant to the backup rings to facilitate smooth initial seating without torque spiking.