Graco 104749 Backup Ring

Graco 104749 Ring, Backup – Precision Seal Support Element

Compatible Machines

• Graco fluid-handling pumps and proportioners with backup seal arrangements
• Graco high-pressure spraying systems requiring internal seal support
• Graco maintenance kits for pump or valve rebuild where backup rings are required
• Graco industrial finishing and coating rigs with dynamic sealing assemblies

Product Description

The Graco 104749 Ring, Backup is a high-precision sealing support ring designed to reinforce primary seals in high-pressure and high-cycle fluid systems. It acts as a structural member behind an O-ring or lip-seal to prevent extrusion, maintain proper geometry under load, and extend the life of critical sealing components.

Key Features

• High-strength ring support: Adds structural integrity behind soft seals to prevent deformation under pressure.
• OEM-specified part: Engineered specifically for compatibility with Graco equipment.
• Compact form factor: Easily fits within existing seal grooves and cavities.
• Extends seal service life: By protecting against extrusion and wear in demanding environments.
• Easy to replace: Simplifies maintenance of internal seal assemblies and reduces downtime.

Technical Specifications

Applications

This ring is used in situations where traditional seals are subject to extrusion, wear or failure due to cyclic pressure or temperature extremes. Within Graco systems, the 104749 backup ring supports high-duty pumps, proportioning modules, and fluid controllers where reliable seal performance is crucial for system longevity and process consistency.

Performance Advantages

• Prevents primary seal extrusion under high differential pressure.
• Maintains seal geometry and improves repeatability of performance cycles.
• Reduces frequency of seal replacement and lowers maintenance costs.
• Supports stable fluid handling by preserving pressure integrity.
• Optimised for OEM assemblies and helps maintain warranty-compliance.

Maintenance Tips

When servicing the assembly, inspect the backup ring for flattening, cracking or evidence of seal extrusion. Clean the groove and mating surfaces thoroughly, then reinstall the ring ensuring correct orientation and no damage. Replace if the ring shows deformation or has worn beyond specified tolerances to maintain proper sealing function.

Frequently Asked Questions