VALVE,RELIEF,PRESSURE AND TEMPER. Key specifications include material: COPPER ALLOY 464 SEAT, seat_radius: 0.625 INCHES NOMINAL IN, thread_class: 3A SINGLE THREADED PORTION A, thread_length: 0.093 INCHES NOMINAL SINGLE THREADED PORTION IN, flange_diameter: 1.500 INCHES NOMINAL IN, special_features: NHA VALVE TEMP RELEASE. This product is currently in active production with full OEM support.
This part is cataloged in the Federal Logistics Information System (FLIS) under NSN 4820-01-469-7578, indicating validated use in U.S. government and defense logistics supply chains. Available through authorized enterprise resellers and TPM (Third Party Maintenance) channels.
Verify compatibility with your specific system configuration before ordering.
| material | COPPER ALLOY 464 SEAT |
| seat_radius | 0.625 INCHES NOMINAL IN |
| thread_class | 3A SINGLE THREADED PORTION A |
| thread_length | 0.093 INCHES NOMINAL SINGLE THREADED PORTION IN |
| flange_diameter | 1.500 INCHES NOMINAL IN |
| special_features | NHA VALVE TEMP RELEASE |
| style_designator | THREADED FLANGED |
| nominal_thread_size | 1.250 INCHES SINGLE THREADED PORTION IN |
| under_flange_height | 0.093 INCHES NOMINAL IN |
| body_inside_diameter | 0.937 INCHES MINIMUM AND 0.938 INCHES MAXIMUM IN |
| seating_surface_shape | RADIAL |
| end_item_identification | W/S NIMITZ CLASS CVN |
| NSN | 4820-01-469-7578 |
| BODY INSIDE DIAMETER | 0.937 INCHES MINIMUM AND 0.938 INCHES MAXIMUM IN |
| MATERIAL | COPPER ALLOY 464 SEAT |
| SPECIFICATION/STANDARD DATA | 75545-QQ-B639 GOVERNMENT STANDARD |
| MATERIAL DOCUMENT AND CLASSIFICATION | QQ-B-639 FED STD SINGLE MATERIAL RESPONSE SEAT |
| STYLE DESIGNATOR | THREADED FLANGED |
| SPECIAL FEATURES | NHA VALVE TEMP RELEASE |
| SEAT RADIUS | 0.625 INCHES NOMINAL IN |
| FLANGE DIAMETER | 1.500 INCHES NOMINAL IN |
| NOMINAL THREAD SIZE | 1.250 INCHES SINGLE THREADED PORTION IN |
| THREAD LENGTH | 0.093 INCHES NOMINAL SINGLE THREADED PORTION IN |