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740478-1 — SEAT,HELICAL COMPRESSION SPRING

✓ Government record, cited
— · ORING SEAL
PRODUCT OVERVIEW

740478-1: SEAT,HELICAL COMPRESSION SPRING.

SEAT,HELICAL COMPRESSION SPRING. Key specifications include end_diameter: 1.0030 INCHES MINIMUM AND 1.0050 INCHES MAXIMUM IN, bore_diameter: 0.8000 INCHES NOMINAL IN, overall_height: 0.1350 INCHES MINIMUM AND 0.1550 INCHES MAXIMUM IN, style_designator: SEAT, surface_treatment: ANODIZE, first_step_diameter: 1.2410 INCHES MINIMUM AND 1.2430 INCHES MAXIMUM IN. This part is cataloged in the U.S.

Government catalog under NSN 5340-01-036-5779, 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.

WHERE IT FITS
740478-1
NSN: 5340-01-036-5779
FSC: 5340 — Hardware, Commercial
CAGE: 73030 — HAMILTON SUNDSTRAND CORPORATION DBA COLLINS AEROSPACE (USA)
SPECIFICATIONS
end_diameter1.0030 INCHES MINIMUM AND 1.0050 INCHES MAXIMUM IN
bore_diameter0.8000 INCHES NOMINAL IN
overall_height0.1350 INCHES MINIMUM AND 0.1550 INCHES MAXIMUM IN
style_designatorSEAT
surface_treatmentANODIZE
first_step_diameter1.2410 INCHES MINIMUM AND 1.2430 INCHES MAXIMUM IN
distance_from_end_to_first_step0.1100 INCHES MINIMUM AND 0.1200 INCHES MAXIMUM IN
NSN5340-01-036-5779
COMPONENT DIAGRAM
O-RING / SEAL — MATERIAL DETERMINES APPLICATION ID: — CROSS-SECTION CS: — SPECIFICATION Material: — Durometer: — Temp: — PN: 740478-1 MFR: OEM ⚠ VERIFY BEFORE ORDERING Wrong material = failure. Viton for oil/fuel, EPDM for water/steam, Buna-N for general purpose, Silicone for food-grade. Chemical incompatibility causes swelling, brittleness, or rapid degradation ✓ BROKER TIP Durometer (hardness) affects sealing pressure tolerance. Higher Shore A = harder = higher pressure. Standard durometer is 70A — verify if application requires different hardness PARTSTABLE TECHNICAL DRAWING — NOT TO SCALE
KEY FEATURES
•
FIRST STEP DIAMETER: 1.2410 INCHES MINIMUM AND 1.2430 INCHES MAXIMUM IN
•
END DIAMETER: 1.0030 INCHES MINIMUM AND 1.0050 INCHES MAXIMUM IN
•
DISTANCE FROM END TO FIRST STEP: 0.1100 INCHES MINIMUM AND 0.1200 INCHES MAXIMUM IN
•
STYLE DESIGNATOR: SEAT
•
SURFACE TREATMENT: ANODIZE
•
BORE DIAMETER: 0.8000 INCHES NOMINAL IN
TECHNICAL CHARACTERISTICS
OVERALL HEIGHT0.1350 INCHES MINIMUM AND 0.1550 INCHES MAXIMUM IN
FIRST STEP DIAMETER1.2410 INCHES MINIMUM AND 1.2430 INCHES MAXIMUM IN
END DIAMETER1.0030 INCHES MINIMUM AND 1.0050 INCHES MAXIMUM IN
DISTANCE FROM END TO FIRST STEP0.1100 INCHES MINIMUM AND 0.1200 INCHES MAXIMUM IN
STYLE DESIGNATORSEAT
SURFACE TREATMENTANODIZE
BORE DIAMETER0.8000 INCHES NOMINAL IN
OTHER ITEMS IN FSC 5340 — Hardware, Commercial
Items in the same Federal Supply class. No interchangeability or substitution relationship is implied.
5340-00-000-0068 5340-00-000-0132 5340-00-000-8150 5340-00-001-1251 5340-00-001-1264 5340-00-001-1265 5340-00-001-1266 5340-00-001-1275
SUBSTITUTES & CROSS-REFERENCES

No substitute or cross-reference records for this part.

LIFECYCLE
NSN statusActive· U.S. Government catalog
Acquisition advice: Normally procured from the manufacturer (OEM)No demilitarization required
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FREQUENTLY ASKED QUESTIONS
What is 740478-1?
740478-1 is a SEAT,HELICAL COMPRESSION SPRING.
What is the NSN for 740478-1?
740478-1 is cataloged in the U.S. Government catalog under NSN 5340-01-036-5779. This indicates validated use in U.S. government and defense supply chains.
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✓ PartsTable — the parts reference. Every fact cited to its source.
PartsTable Design LLC · partstable.com
U.S. Government catalog: edition PUBLOGDVD v12.0.0 (OCT 2026), edition date 2026-10-01, retrieved 2026-10-18.
PartsTable commercial catalog: edition Unified commercial catalog snapshot through 2026-09-28, edition date not on file, retrieved 2026-09-28.