About This Unit

At NC Servo Tech, our shop is equipped to service the MOOG D644-519. We use a consistent process to restore each unit to working condition.

Why Repair With NC Servo

We’ve built our shop around one thing: industrial repair. With decades of hands-on experience and deep product knowledge, we deliver consistent results.

Frequently Asked Questions

Warranty coverage of a 12-month warranty on parts and labor is included with every repair we complete.

Yes. Send us photos of the unit from multiple angles. Our team has serviced thousands of models and can often ID them visually.

Yes, rush service is available for an additional fee. Let us know your deadline when you submit your request.

Part of our intake includes troubleshooting to determine the failure point. We report findings before proceeding.

Send the unit in whatever condition it’s in. We clean everything during teardown before inspection begins.

Repair Process

We disassemble every valve, inspect it inside and out, and clean all moving parts. Components that fail inspection are swapped out before the valve is rebuilt and tested.

  • Seal and Gasket Replacement: Worn seals and gaskets are replaced with new components during every rebuild.
  • Leak and Pressure Testing: The reassembled unit is leak-tested and pressure-tested to verify it meets published specs.
  • Final Performance Verification: After reassembly, each valve is bench-tested against published performance specifications.
  • Cleaning: Units go through a mineral bath, with ultrasonic cleaning used for delicate internals.

Diagnostic Testing

With over a dozen dedicated flow test stands and a Hagenbush proportional valve system, we verify flow curves, hysteresis, frequency response, and more. Performance reports and graphs are available for purchase on request. Our operational testing verifies proper functionality.

Common Applications

Our reliable repair services for the MOOG D644-519 are trusted across various sectors including Steel & Metals, Defense, and Power Generation. We understand the unique demands of valves in these environments.

Technical Specifications

Every MOOG D644-519 we service is tested under typical applications. Our diagnostics verify performance against published specifications. Performance data and Technical diagrams are available for purchase upon request.

Additional MOOG D644-519 Services

Beyond standard maintenance, we offer specialized reconditioning for your MOOG D644-519 unit. Our disassembly process includes spool evaluation and seal replacement, using only new replacement components.

Lead Times and Support

As a specialist for MOOG D644-519 services, NC Servo Tech targets quick resolution with typical lead times of 1 to 2 weeks. Benefit from our responsive technical support to keep your systems running smoothly.

Maintenance Tips

  • Keep a spare MOOG D644-519 on hand to minimize downtime during unplanned failures.
  • Keep hydraulic fluid clean and at proper levels for consistent valve operation.
  • Inspect MOOG D644-519 seals regularly to prevent leaks and maintain performance.

Let Us Repair Your MOOG D644-519

Request pricing, availability, and turnaround for your MOOG D644-519. NC Servo Tech provides warrantied repair with a 1-year warranty. Contact us to set up your repair.

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NC Servo Tech is an independent third-party repair facility. We are not affiliated with, endorsed by, sponsored by, or authorized by MOOG or any original equipment manufacturer (OEM), nor do we claim to be a MOOG service center. All brand names, trademarks, model numbers, and part numbers referenced on this page are the property of their respective owners and are used solely for identification and compatibility purposes.