Graco 15A178 Spring Plate – OEM Regulator Bottom Plate
The Graco 15A178 Spring Plate is a crucial OEM component that forms the lower support for the compression spring inside Graco mechanical regulators. Its robust design ensures stable spring seating and helps maintain consistent regulator performance under high-pressure cycling.
Product Overview
The Spring Plate (Part No. 15A178) is made from high-quality steel to withstand repeated compression cycles. Positioned at the bottom of the regulator spring assembly, it evenly distributes spring force, helping to prevent deformation and fatigue. This OEM plate is specifically engineered for Graco’s mechanical regulator models, ensuring reliable and long-lasting performance when replacing worn or damaged internal parts.
Key Features
- Genuine Graco OEM part — Part Number: 15A178
- Durable steel construction built for high-stress environments
- Provides reliable bottom support for the regulator spring
- Enhances spring stability and preload consistency
- Helps prevent spring fatigue, wear, or permanent deformation
Technical Specifications
| Part Number |
15A178 |
| Description |
Spring Plate, Bottom |
| Material |
High-strength steel |
| Weight |
Approximately 0.045 lb |
| Usage |
Mechanical / pneumatic regulator assemblies |
Compatible Systems
- Graco Mechanical Regulators (e.g., Part No. 233767, 233768, 234260, 233814)
- Graco P200‑RM NPT Pneumatic Regulator Series
- Back‑pressure and fluid‑pressure regulators used in spray finishing systems
Installation
To install the Graco 15A178 Spring Plate properly, follow these steps carefully:
- Fully depressurize the regulator before disassembling.
- Remove the regulator’s lower housing or disassemble the bottom portion.
- Take out the existing spring plate and inspect the spring and other internals for wear.
- Insert the new 15A178 Spring Plate, ensuring it sits flat and evenly.
- Reassemble the regulator housing, making sure to align all parts correctly.
- Repressurize slowly and perform a test cycle to verify correct spring support and stable regulator operation.
Why Use the 15A178 Plate
Replacing an old or worn spring plate with this OEM 15A178 part restores the regulator’s original spring geometry and preload stability. This results in improved pressure consistency, reduced internal fatigue, and extended lifespan of the regulator assembly.
Maintenance Tips
- Inspect the spring plate during every major service or when the regulator’s performance degrades.
- Clean the plate gently and check for signs of pitting or deformation.
- If damage is detected, replace the plate promptly along with the compression spring if needed.
- Use proper torque settings when reassembling the regulator housing.
Frequently Asked Questions
The plate sits at the bottom of the compression spring, providing a stable base that keeps the spring aligned and helps maintain consistent preload.
Yes, it is used in certain P200‑RM series mechanical regulators, as indicated in Graco parts lists.
It is not recommended to reuse a worn or deformed spring plate — replacing it with a new OEM part helps restore proper spring behavior and regulator performance.
During preventive maintenance or if regulator cycling or pressure becomes inconsistent, inspect the plate, and consider replacing it if there are any signs of wear or damage.
